CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of priority to U.S. Provisional

Patent Application Serial No. 62/642,787 entitled“Halide Injection System,” filed March 14, 2019, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

[0002] The combustion and gasification of fossil fuel such as coal generates flue gas that contains mercury and other trace elements that originate from the fuel. The release of the mercury (and other pollutants) to the environment can be controlled using sorbents, scrubbers, filters, precipitators, and other removal technologies. Mercury is initially present in the elemental form during combustion and gasification. Some of the elemental mercury becomes oxidized in the flue gas downstream of the furnace. The amount that is oxidized depends on the amount of acid gases present in the flue gas, residence time, gas temperatures, and other factors. Am ounts of mercury vary with the fuel, but concentrations of mercury in the stream of flue gas from coal combustion are typically less than 5 parts per billion (ppb). Large coal combustion facilities such as electric utilities may emit a pound of mercury' or more per day. Mercury removal applications include, without limitation, flue gas from coal (or other fossil fuel) combustion, waste incineration, product gas from gasification, as well as off gases from mineral processing, metal refining, retorting, cement manufacturing, chlora!kali plants, dental facilities, and crematories.

SUMMARY OF THE DISCLOSURE

[0003] The present disclosure provides a system for separating mercury from a mercury-containing gas. The system includes a coal -feed zone. The system further includes a combustion zone located downstream of the coal-feed zone and configured to receive a supply of coal from the coal-feed zone and to combust at least a portion of the supply of coal and produce the mercury- containing gas. The system further includes a scrubbing zone located

downstream of the combustion zone for receiving the mercury-containing gas and removing at least a portion of the mercury from the mercury-containing gas. The system further includes a supply of a halogen of halide to be injected or added to the system. The system further includes one or more halide or halogen injection or addition points located at least one of at, upstream, and downstream of at least one of the coal -feed zone, the combustion zone, and the scrubbing zone.

[0004] The present disclosure further provides a method of separating mercury from a mercury-containing gas using a system that includes a coal-feed zone. The system further includes a combustion zone located downstream of the coal-feed zone and configured to receive a supply of coal from the coal-feed zone and to combust at least a portion of the supply of coal and produce the mercury-containing gas. The system further includes a scrubbing zone located downstream of the combustion zone for receiving the mercury-containing gas and removing at least a portion of the mercury from the mercury-containing gas. The system further includes the addition or injection of a supply of a halide or halogen. The system further includes one or more halide or halogen injection points located at least one of at, upstream, and downstream of at least one of the coal-feed zone, the combustion zone, and the scrubbing zone. The method includes supplying coal from the coal-feed zone to the combustion zone. The method further includes injecting the halide or halogen into the system through the one or more injection points. The method further includes contacting the halide or halogen with mercury in the mercury-containing gas to produce oxidized mercury. The method further includes collecting the oxidized mercury in at least one of the particulate removal and scrubbing zone.

[0005] The present disclosure further provides a liquid dispersion lance for injecting an atomized liquid halide or halogen. The liquid dispersion lance includes a shell extending from first and second opposed ends. The liquid dispersion lance further includes a halogen or halide channel extending from an inlet proximate to the first end to an outlet proximate to the second end. The liquid dispersion lance further includes a first compressed air channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end. The liquid dispersion lance further includes a second compressed air channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[0006] The present disclosure further provides a liquid dispersion lance for injecting an atomized liquid halide or halogen. The liquid dispersion lance includes a shell extending from first and second opposed ends. The liquid dispersion lance further includes a compressed air channel extending from an inlet proximate to the first end to an outlet proximate to the second end. The liquid dispersion lance further includes a first halogen or halide channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end. The liquid dispersion lance further includes a second halogen or halide channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[0007] The present disclosure further provides a solid dispersion lance for injecting a solid halide or halogen. The solid dispersion lance includes a shell extending from first and second opposed ends. The solid dispersion lance includes a dispersion head at least partially disposed within the shell and adapted to dispense the solid halogen or halide through the injection point.

[0008] There are many non-limiting benefits to using the disclosed systems and methods, at least some of which are unexpected . For example, according to some embodiments, a liquid, solid, or gaseous halogen or halide can be introduced into a combustion system at almost any location. According to some embodiments, the ability to introduce the halogen or halide at any location can allow for optimization of the oxidation and removal of mercury throughout the system. Also, according to some embodiments, the level of the halogen or halide can be introduced in a location or at a level that can minimize the degree of corrosion of the components of the system potentially caused by the halogen or halide. According to some embodiments, components of the systems can be retrofitted onto existing systems to optimize an existing system’s performance. According to some embodiments, the components of the systems can be selectively skid-mounted to provide on-site introduction of the halogen or halide to systems. According to some embodiments, the lances described herein can be made of a heat-degradable material, which can allow for facile replacement at the end of the lance’s serviceable lifetime. According to some embodiments, the lance can be adapted to use the halide, halogen, or compressed air as a coolant to maintain the lance’s integrity when exposed to extreme heat

BRIEF DESCRIPTION OF THE FIGURES

[0009] The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0010] FIG. 1 is a schematic diagram of a combustion system, in accordance with various embodiments.

[0011] FIG. 2 is a schematic depiction of another combustion system, in accordance with various embodiments.

[0012] FIG. 3 is a schematic depiction of an injection system, in accordance with various embodiments.

[0013] FIG. 4 is a schematic depiction of another injection system, in accordance with various embodiments.

[0014] FIG. 5 is a schematic depiction of another injection system, in accordance with various embodiments.

[0015] FIG. 6 is a schematic depiction of another injection system, in accordance with various embodiments.

[0016] FIG. 7A is a sectional view of an embodiment of a liquid halogen or halide lance, in accordance with various embodiments.

[0017] FIG. 7B is a sectional view of the liquid halogen or halide lance taken along line A- A of FIG. 7A, in accordance with various embodiments.

[0018] FIG. 7C is a sectional view of the liquid halogen or halide lance rotated 90 degrees relative to FIG. 7A, in accordance with various embodiments.

[0019] FIG. 7D is a sectional view ⁷ of the liquid halogen or halide lance taken along line B-B of FIG. 7C, in accordance with various embodiments.

[0020] FIG. 8A is a sectional view of an embodiment of another liquid halogen or halide lance, in accordance with various embodiments. [0021] FIG. 8B is a sectional view of the liquid halogen or halide lance taken along line A-A of FIG. 8 A, in accordance with various embodiments.

[0022] FIG. 8C is a sectional view of the liquid halogen or halide lance rotated 90 degrees relative to FIG. 8A, in accordance with various embodiments.

[0023] FIG. 8D is a sectional view of the liquid halogen or halide lance taken along line B-B of FIG. 8C, in accordance with various embodiments.

[0024] FIG. 9 A is a sectional view' of a solid halogen or halide lance, in accordance with various embodiments.

[0025] FIG. 9B is an exploded view _' of the solid halogen or halide lance of FIG 9 A, in accordance with various embodiments.

[0026] FIG. 10 is a sectional view' of the solid dispersion lance disposed in an injection point which is adapted as a bore in a door of a boiler, in accordance with various embodiments.

[0027] FIG. 11 is a sectional view of the solid dispersion lance disposed in an injection point which is adapted as a bore in another door of a boiler, in accordance with various embodiments.

[0028] FIG. 12 is a sectional view of the solid dispersion lance disposed in an injection point which is adapted as a bore in a wall of a boiler, in accordance with various embodiments.

[0029] Reference will now be made in detail to certain embodiments of the disclosed subject matter, examples of which are illustrated in part in the accompanying drawings. While the disclosed subject matter will be described in conjunction with the enumerated claims, it will be understood that the exemplified subject matter is not intended to limit the claims to the disclosed subject matter.

[0030] Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of

“about 0.1% to about 5%” or“about 0.1% to 5%” should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4 4%) within the indicated range. The statement“about X to Y” has the same meaning as“about X to about Y,” unless indicated otherwise. Likewise, the statement“about X, Y, or about Z” has the same meaning as“about X, about Y, or about Z,” unless indicated otherwise.

[0031] In this document, the terms“a,”“an,” or“the” are used to include one or more than one unless the context clearly dictates otherwise. The term“or” is used to refer to a nonexclusive“or” unless otherwise indicated. The statement “at least one of A and B” has the same meaning as“A, B, or A and B.” In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting, information that is relevant to a section heading may occur within or outside of that particular section.

[0032] In the methods described herein, the acts can be carried out in any order without departing from the principles of the disclosure, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

[0033] The term“about” as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range

[0034] The term“substantially” as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99 9%, 99 99%, or at least about 99 999% or more, or 100%.

[0035] The term“halide” as used herein is defined as a compound formed from the reaction of a halogen with another element or radical. In general, halide compounds are much less reactive than the molecular halogens, having a low chemical potential in some cases, the terms halide and halogen are used interchangeably. The term halide can represent a liquid, a solid, or a gas, or a mixture thereof. The liquid, or halide solution, or halide-salt solution, can contain any amount of halide. The liquid halide can be bromide, chloride, or iodide containing solutions, or a mix thereof. The solid halide, or solid halide mixture, can contain any amount of halide or halogen. The solid, or solid mixture containing the halide or halogen can be in the form of a salt, or any material. The solids can be bromide, chloride, or iodide containing solids (or salts), or a mixture with other materials. The halide gas, or halide gas mixture, can contain any amount of halide or halogen. The gas can be bromide, chloride, or iodide containing gases (or vapors), or a mixture with other gases.

[0036] Disclosed herein are fossil fuel combustion systems that can be suited for many applications such as electrical power generation, or generation of process steam. The combustion of the fossil fuel can release various pollutants into a vaporous gas stream (e.g., a flue gas). In order to reduce the amount of pollutants into the environment it is desirable to capture at least a portion of the pollutants from the gas stream, or convert at least a portion of the pollutants to an oxidized form, or convert at least a portion of the pollutants into an inert form.

[0037] FIG. 1 is a schematic diagram of a combustion system 10.

Combustion system 10 includes fossil fuel feed zone 12, combustion zone 14, particulate and scrubbing zone 16, and discharge zone 18. Relative to a flow of the fossil fuel or a gas stream emanating from the combustion of the fossil fuel, fossil fuel feed zone 12 is upstream of combustion zone 14, which is upstream of particulate and scrubbing zone 16, which is upstream of discharge zone 18.

Zones 12, 14, 16, and 18 can include many different components. Many of the individual components of FIG 1, and any subsequent figures, can be present as single component or can be present as one of any plural number of the component.

[0038] Fossil fuel feed zone 12 can include a fossil fuel such as coal 20.

The fossil fuel can be pure coal in that there are substantially no fillers or otherwise diluted coal. For example, the coal 20 can range from about 5 wt% to about 100 wt% coal, about 80 wt% to about 100 wt% coal, or less than, equal to, or greater than about 5 wt%, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 wt% coal. Cofiring coal with other fuels such as biomass or natural gas is also possible at different wt% values. In embodiments including coal 20, fossil fuel feed zone 12 can be referred to as a coal feed (or fuel feed) zone. As shown, FIG. 1 further includes coal bunker 22, coal feeder 24, and pulverizer 26. Coal 20 can be supplied to bunker 22 through any suitable method. For example, coal 20 can be fed directly from a track or train car to bunker 22 or from source to bunker 22 by a boom including a conveyer system. Coal 20 can be supplied to coal feeder 24 continuously or selectively. Coal feeder 24 can be controlled to send a predetermined amount of coal 20 either to pulverizer 26 or directly to combustion zone 14. If coal 20 is fed into pulverizer 26, coal 20 can be pulverized to any degree desirable. Pulverized coal 20 can then be fed into combustion zone 14, for example, manually or through a conveyer system

[0039] Combustor zone 14 includes boiler 28. Boiler 28 is heated to a temperature sufficient to combust coal 20 (or any other fossil fuel). As an example, the combustion zone (or furnace) of boiler 28 can be heated to a temperature in a range of from about 500 °C to about 5000 °C, about 1000 °C to about 4000 °C, about 2000 °C to about 3000 °C, or less than, equal to, or greater than about 500 °C, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, or about 5000 °C. The temperature in boiler 28 need not be constant across all regions of boiler 28. For example, a gradient of temperatures across boiler 28 may be present. The temperature at the location (e.g., the combustion location) where coal 20 is injected or otherwise supplied to boiler 28 may be the greatest. The temperature within boiler 28 at regions downstream of the combustion (furnace) location may be progressively lower, from 5000 °C (exit of furnace) to 400 °C, or lower. Subsequent temperatures beyond this may become progressively lower after leaving the boiler and into entry of the particulate and scrubbing zone 16, from 400-500 ° C to 50-100 °C.

[0040] Combustion of coal 20 results in the formation of flue gas. The flue gas passes through boiler 28 into the particulate and scrubbing zone 16. In zone 16, pollutants in the flue gas are removed. Other components in the flue gas can also be removed in scrubbing zone 16. The particulate and scrubbing zone 16 can include many components. For example, as shown in FIG. 1, scrubbing zone 16 includes selective catalytic reduction system 30, air preheater(s) 32, electrostatic precipitator(s) 34, fabric filter (s) 34, induced draft fan(s) 36, scrubber 38, and wet electrostatic precipitator 40. Other embodiments of system 10 can include additional or fewer components. In other embodiments, the components of scrubbing zone 16 can be arranged in different orders.

[0041] Selective catalytic reduction system 30 is downstream of boiler

28. System 30 and boiler 28 can be connected via a duct to transport flue gas therebetween. Selective catalytic reduction system 30 can be used to convert nitrogen oxides into diatomic nitrogen and water. To accomplish this, system 30 can use a variety of catalysts wliich may be metal oxides or activated carbons. Where present, activated carbon can be injected into flue gas ahead or upstream of a particle separator.

[0042] Air preheater 32 is located downstream of selective catalytic reduction system 30. Preheater 32 and system 30 can be connected through a duct to transport the flue gas therebetween. Air preheater 32 can heat the flue gas prior to entry into any other systems of scrubber zone 16. For certain

applications, air preheater 32 can be helpful to increase the thermal efficiency of system 10 by making it easier to separate components from the flue gas

[0043] Any one or both of electrostatic precipitator (ESP) and fabric filter (FF or BH) 34 can be located either upstream or downstream of air preheater 32. Electrostatic precipitator 34 and air preheater 32 can be connected via a duct to transport the flue gas therebetween. An electrostatic precipitator is a filtration device that removes fine particles, (e.g., dust and smoke) from a flowing gas using the force of an induced electrostatic charge while minimally impeding the flow of gases through the unit. In other embodiments, system 10 can include a baghouse filter in addition to or instead of electrostatic precipitator 34. A baghouse filter is a filter that includes a fabric or cloth that filters solid particles out of the flue gas. Some systems may use a combination of at least one electrostatic precipitator and a fabric filter.

[0044] Induced draft fan 36 is downstream of electrostatic precipitator

34. Induced draft fan 36 and electrostatic precipitator 34 can be connected through a duct to transport flue gas therebetween. Induced draft fan 36 functions to push the flue gas from electrostatic precipitator 34 through system 10 towards discharge zone 18. From induced draft fan 36, the flue gas can flow to either or both of scrubber 38 or wet electrostatic precipitator 40.

[0045] Scrubber 38 can be located downstream or upstream of induced draft fan 36. In some applications a booster fan (not shown) is also used.

Scrubber 38 and induced draft fan 36 can be connected through a duct to transport flue gas therebetween. As shown in FIG 1, scrubber 38 is a wet scrubber. A wet scrubber can remove solid or gaseous pollutants (e.g., mercury) as well as other undesirable solids or liquids from the flue gas stream. In general, a wet scrubber works by contacting a target compound, such as a pollutant (e.g. SO2), with a scrubbing solution or slurry. The scrubbing solution or slurry' can include water, or reagent (e.g. limestone or a lime based reagent, an ammonia based reagent, a sodium based reagent, an amine based reagent), and mixture thereof. The scrubbing solution can be made of chemicals that are effective for removal of mercury, SO2, SO3, NQx, HC1, and C0 _2. The scrubbing solution can be dispensed within scrubber 38 in a variety of ways. For example, scrubber 38 includes at least one spray bar 42. Spray bar 42 is fed with the scrubbing solution or slurry' from an external source such as a tank. The solution or slimy is then sprayed within scrubber 38 in such a manner as to contact the flue gas and remove the pollutant or other target material from the flue gas. The pollutant or other material can then be collected in scrubber 38 and removed therefrom. In another example, the solution may serve as a bubbling bath as the flue gas with the pollutant pass (bubbles) through the solution.

[0046] Wet electrostatic precipitator 40 is located downstream of scrubber 38 Wet electrostatic precipitator 40 and wet scrubber 38 can be connected through a duct to transport flue gas therebetween. Generally, a w ^? et electrostatic precipitator operates by contacting the flue gas with a water-vapor- saturated air stream (e.g., having 100% relative humidity). The target particle or pollutant and the water form a moving slurry' that can be collected and removed from system 10.

[0047] After passing through wet electrostatic precipitator 40, the flue gas exits scrubbing zone 16 and enters discharge zone 18, which includes stack

44. The flue gas entering stack 44 exits stack 44 and is discharged into the atmosphere. Pollutants (or emissions) targeted for removal (e.g., NOx, SO , particulate matter (PM), HC1, Mercury) can be monitored at the stack 44.

Process conditions such as load, flow, pressure, and temperatures are also monitored/measured. This data can be used to adjust, either manually or automatically, halide injection rates.

[0048] FIG. 2 is a schematic depiction of combustion system 10’.

Combustion system 10’ shares many of the same features as combustion system 10. A difference between system 10 and system 10’ is that system 10’ includes a dry scrubber 47 as opposed to a wet scrubber 38. Generally, a dry or semi-dry' scrubbing system, unlike the wet scrubber, does not saturate the flue gas stream that is being treated with moisture. While there are a number of dry type scrubbing system designs, most include two main sections or devices: a device to introduce the acid gas sorbent material into the gas stream and a particulate matter control device to remove reaction products, excess sorbent material, as well as any particulate matter already in the flue gas. Dry scrubbing systems can be categorized as dry' sorbent inject! on(DSI) or as spray dryer absorbers (SDAs). Dry sorbent injection involves the addition of an alkaline material (e.g., hydrated lime, soda ash, iron a, or sodium bicarbonate) into the gas stream to react with the acid gases. The sorbent can be injected directly into several different locations: the combustion process, the flue gas duct (ahead of the particulate control device), or an open reaction chamber (if one exists). The acid gases react with the alkaline sorbents to form solid salts which are removed in the particulate control device. In spray dryer absorbers, the flue gases are introduced into an absorbing tower (dryer) where the gases are contacted with a finely atomized alkaline slimy. Acid gases are absorbed by the slurry mixture and react to form solid salts which are removed by the particulate control device. The heat of the flue gas is used to evaporate all the water droplets, leaving a non-saturated flue gas to exit the absorber tower.

[0049] A further difference between system 10 and system 10’ is that electrostatic precipitator (or fabric filter) 34 and induced draft fan 36 are located downstream of the scrubber (e.g., 38 or 47) in scrubbing zone 16. Furthermore, system 10’ is generally free of wet electrostatic precipitator 40. The respective systems 10 and 10’ of FIGS. 1 and 2 are merely illustrative of two systems that are contemplated by this disclosure. Systems 10 and 10’ do not limit the disclosure as many other systems with additional or different components and arrangements of the same are within the scope of the disclosure.

[0050] A pollutant of interest for removal from the flue gas in systems 10 and 10’ is mercury. The mercury can be liberated through the combustion of coal. The gaseous mercury that produced is mostly in the elemental form. To remove mercury from the flue gas, however, it is desirable to oxidize the mercury. An effective way to oxidize the mercury is to contact the flue gas with a reactive halogen or halide. Upon contact between the flue gas and the halogen or halide a mercury-halide (Hg-halide) complex is formed in which the elemental mercury is oxidized. Once the mercury is oxidized, it may be removed through interacting with any one of or all components of scrubbing zone 16.

[0051] The halide or halogen can be supplied to system 10 or 10’ in many suitable forms. The halogen or halide can be solid, liquid, gas, or a mixture thereof. For example, of the total amount of halogen or halide in system 10 or 10’, 100 wt% of the halogen or halide can be solid, liquid, or gaseous.

Alternatively, less than 100 wt% of the halogen or halide can be solid, liquid, or gaseous. The halogen or halide can be chosen from HC1, HBr, HI, Br ₂ , Cl ₂ , h, BrCl, IBr, ICi, C1F, PBn PC1 _5, SC1 ₂ , CuCb, CuBr ₂ , Al ₂ Br ₆ , l ei, FeBr _y , FeO _z , MnBn, MnCfr, MBr _% NiCfr, Nifr, ZnBr ₂ , ZnCfr, Znk M l dir, M i ;Ch M i d. NH ₄ F, FeNH ₄ Br _4, FeNHUCU, F ₂ , F\ CT Br , G, NH ₄ Br, NaBr, CaBr ₂ , NaCl, CaCl ₂ , NH4CI, NH4I, Nal, Cal ₂ , KI, KC1, HI, NH ₄ F, NaF, CaF ₂ , HF, LiBr, AgCl, AgBr, (Ί P ;, CH; Br, AuBr, MgBr ₂ , MgCfr, hydrates thereof, and combinations thereof wherein x, y, and z are independently 1, 2, 3, or 4. In various

embodiments, where a halide salt is contacted with coal or injected into the combustion zone, the halide salt can generate a corresponding halide or halide salt in the flue gas which, alone or in combination with injection of an activated carbon into the gas, can remove mercury.

[0052] In embodiments including a liquid halide or halogen, the halide or halogen may constitute 100 wt% of the liquid. Alternatively, the halide or halogen can be diluted to any suitable concentration. For example, the liquid can have a halogen or halide concentration in a range of from about 5 wt% to about

99.99 wt%, about 40 wt% to about 60 wt%, about 42 wt% to about 58 wt%, or less than, equal to, or greater than about 5 wt%, 6, 7, 8, 9, 10, I I , 12, 13, 14, 15,

16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,

37, 38, 39, 40, 41 , 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,

58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,

79, 80, 81, 82, 83, 84, 85, 86. 87, 88, 89. 90, 91, 92, 93, 94. 95, 96, 97. 98, 99, or about 99.99 wt%. Examples of suitable solutions include those having up to 58 wt% calcium bromide, up to 48 wt% sodium bromide, up to 58 wt% sodium iodide, up to 42 wt% calcium chloride, or up to 48 wt% of hydrogen bromide. Solvents for the halogen or halide can include as by example water, organic solvents (e.g. methanol, isopropyl alcohol), polar and nonpolar, or mixtures thereof. In embodiments including a solid halide or halogen, the halide or halogen may be present as a mixture with an alkali, a clay, a metal, or a combination thereof. In those embodiments the halide or halogen may account for about 5 wt% to about 99.99 wt% of the mixture, about 40 wt% to about 60 wt%, about 42 wt% to about 58 wt%, or less than, equal to, or greater than about 5 wt%, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,

48, 49, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68,

69, 70, 71 , 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,

90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or about 99.99 wt%. In embodiments in which the halide or halogen is mixed with an alkali, the alkali can be chosen from limestone, lime, carbonates, and a combination thereof as examples.

Examples of clay based materials may include hydrous aluminum phyllosilicates which can include a kaolin group (e.g. kaolinite, dickite, halloysite,

and nacrite (polymorphs of Al ₂ Si ₂ 0 ₅ (0H) ₄ )), a smectite group (e.g. dioctahedral smectites such as bentonite, montmorillonite, nontronite and beidellite and tri octahedral smectites), a Mite group (e.g. clay-micas), other clays include sepiolite, attapulgite, clays with long water channels internal to their structure. Examples of the metals are base metals, precious metals, ferrous metals, nonferrous metals, noble metals, heavy metals, gold, silver, platinum, palladium, iron, lead, nickel, copper, zinc, aluminum, tin, manganese, magnesium, and oxides thereof To help promote flow of the solid halide or halogen, the mixture may further include a flow agent in addition to or substituted for any of the alkali, metal, clay, or combination thereof. Suitable examples of flow agents may include silica, alumina, metal, or a combination thereof.

[0053] Examples of suitable solid halogen or halides include a solid, or solid mixture, of up to 100 wt% calcium bromide, or calcium chloride, or calcium iodide, or sodium bromide, sodium chloride, sodium iodide, or potassium bromide, or potassium chloride, or potassium iodide, 80% sodium bromide and 20% bentonite, or 80% calcium bromide and 20% bentonite, 80% potassium iodide and 20 % bentonite, or 50% sodium bromide and 50% bentonite, or 50% calcium bromide and 50% bentonite, or 50% potassium iodide and 50 % bentonite, 65% sodium bromide, 25% bentonite, and 10% iron oxide (ferric oxide) or 65% potassium iodide, 25% bentonite, and 10% iron oxide (ferric oxide). Additional examples include 80% sodium bromide and 20% alkali (limestone or lime), or 80% calcium bromide and alkali (limestone or lime), 80% potassium iodide and alkali (limestone or lime), or 50% sodium bromide and 50% alkali (limestone or lime), or 50% calcium bromide and 50% alkali (limestone or lime), or 50% potassium iodide and 50 % alkali (limestone or lime). Further examples include: 65% sodium bromide, 25% bentonite, and 10% iron oxide (ferric oxide) or 65% potassium iodide, 25% bentonite, and 10% iron oxide (ferric oxide). Any ratio of halide mixed with another material or materials is acceptable

[0054] The halide or halogen can be injected into system 10 or 10’ in many suitable manners. For example, as shown in FIGS 1 and 2, systems 10 and 10’ each include multiple injection (addition) points 46 (denoted by the arrow head). As shown in FIGS 1 and 2, injection points 46 can be present at many locations in system 10 or 10’ System 10 or 10’ can include as few as one injection point 46 or any number of injection points 46. Injection points 46 can be a located at any desired location in system 10 or 10’ For example, injection point 46 may be located at least one of at, upstream, and downstream of at least one of fossil fuel feed zone 12, combustion zone 14, scrubbing zone 16, and any ducts therebetween. With respect to fossil fuel feed zone 12, injection points 46 can be located at least one of at, upstream, and downstream of at least one of coal bunker 22, coal feeder 24, or coal pulverizer 26 Injection point 46 can also be located such that the halide or halogen is injected onto coal 20 before entering system 10 or 10’. As used herein“injection” can he meant to include adding the halogen or halide directly to any component of the system. For example, injecting the halide or halogen to coal can include adding the halide or halogen to coal at a location upstream of the boiler.

[0055] Adding halide or halogen to coal upstream of the boiler can mean that the halogen or halide is added to the coal before the coal is combusted. This can be accomplished by mixing the halogen or halide with the coal prior to entering system 10 or 10’. Alternatively, as mentioned herein, the halogen or halide can be supplied to the coal through any injection point 46 prior to combustion. The ability to add the halogen or halide to the coal prior to combustion allows for the creation of a hybrid coal that is capable of combustion and includes components that are useful in separating or removing mercury from the flue gasses created by the combustion of the coal.

[0056] With respect to combustion zone 14, injection points 46 can be located at least one of at, upstream, or downstream of boiler 28. in embodiments where injection points 46 are located at boiler 28, injection points 46 can be located adjacent to any one or more temperature zones of boiler 28. In combustion zone 14, the injection points 46 can be located at any duct feeding boiler 28 or any duct leading from boiler 28.

[0057] With respect to scrubbing zone 16, injection points 46 can be located at least one of at, upstream, and downstream of at least one of selective catalytic reduction system 30, air preheater 32, electrostatic precipitator 34 (or baghouse filter, if present), scrubber 38, scrubber 47 or wet electrostatic precipitator 40. In embodiments in which scrubber 38 is a wet scrubber, injection points 46 can be located at spray bar 42 such that the halogen or halide can be injected concurrently with the scrubbing solution or slurry.

[0058] Injection points 46 can include any structure or feature that will allow the halogen or halide to enter system 10. For example, an injection point 46 can be an orifice, a hole, a passage, an opening, a valve, a pipe. In some embodiments, injection point 46 can be an open location where the halide or halogen is simply added to system 10 (e.g., an open end of coal bunker 22 where coal 20 is added). In some embodiments, injection point 46 can be controlled to alternate between a closed and open configuration such that access to system 10 can be selectively controlled.

[0059] Injection points 46 can be configured to allow for the injection of the halogen or halide whether in liquid, gas, or solid form. Injection points 46 can allow for simultaneous injection of the halogen or halide across system 10 or system 10’. For example, the halide or halogen can be injected through each injection point 46 at substantially the same time or through a subset of the total number of injection points 46. The quantity of the halogen or halide in each individual injection point 46 can be the same or different. Additionally, in some embodiments, a quantity of the halide or halogen can be fed through discrete injection points 46, or groupings of injection points 46, at different times. The quantity of the halogen or halide in each individual injection point 46 can be the same or different.

[0060] To effectuate injection of the halogen or halide, any individual injection point 46 can be coupled to an injection system. An example of injection system 100 is shown in FIG. 3, which shows an application of the li qui d hali de injection system in which the halide liquid is added and/or dispersed (sprayed) onto coal 20. System 100 includes tank (or a tote) 110, vent 111, tank fill 112, mixer 1 15, halide metering pump 1 16, solvent tank 118, solvent tank vent 1 17, solvent source 119, solvent metering pump 120, control 140, injection point supply line 125, recirculation line 126, liquid halogen or halide lance 130, and on/off valve 132.

[0061] Tank 110 includes vent 111, fill 1 12, and optional mixer 1 15.

Tank 110 is connected to halide metering pump 116 and recirculation line 126. Halide metering pump 1 16 is connected to injection point supply line 125, recirculation line 126, and to drain 138. Injection point supply line 125 connects to liquid halogen or halide lances 130, which are positioned adjacent to injection points 46. Solvent tank 1 18 is connected to solvent source 119 and includes vent 117. Solvent tank 118 is connected to solvent metering pump 120, which is connected to injection supply line 125 On/off valves 132 are optionally- dispersed throughout system 100.

[0062] Tank 110 is used to contain the liquid halogen or halide solution.

Tank 110 can be skid-mounted for mobility and include fill 112 for suppling tank 1 10 with the halogen or halide solution. Tank 110 also includes vent 1 1 1. In some embodiments, tank 110 can include optional mixer/stirrer 115. Mixer 115 can be used to keep the halide or halogen in solution, to keep the halogen or halide from stratification, and to keep the halide or halogen uniformly mixed.

[0063] The halogen or halide liquid is pumped through system 100 by halide metering pump 116. Metering pump 1 16 can provide a controllable and reliably accurate flow of the liquid halogen or hali de solution. This metering pump 116 can provide more accurate flow compared to other methods of flow control (e.g., flow control valves, meters). Although only one metering pump 1 16 is shown, multiple pumps may be used in system 100.

[0064] It may be desirable to dilute the halogen or halide solution.

Dilution can improve the cost-effectivity of system 100 by using less halogen or halide than a system requiring fully concentrated liquid halogen or halide.

Additionally, diluting the halogen or halide can be helpful in facilitating transport and reducing any potential corrosive effect of the halogen or halide in any of the components in system 10 or 10’. Additionally, diluting the halogen or halide, or controlling the dilution can be helpful in cooling of the halogen or halide at the lance, which can be subject to extreme heat. Further, diluting the halogen or halide, or controlling the dilution can aid in dispersion of the halogen or halide. To dilute the liquid halogen or halide, system 100 can include solvent tank 118. Solvent tank 1 18 can include a solvent such as water, which may be supplied via solvent source 119. The solvent may be pumped from solvent tank 1 18 (or directly from source 1 19, if tank 1 18 is not present) by metering pump 120. Similarly, to metering pump 116, metering pump 120 can provide a controllable and reliably accurate flow of the solvent. Although only one metering pump 120 is shown, multiple pumps may be used. Additionally, metering pumps 116 and 120 may be used interchangeably to pump either the liquid halide solution, or the solvent.

[0065] Metering pumps 116 and 120 feed the liquid halogen or halide as well as the solvent to injection point supply line 125. While only one injection supply line 125 is shown, multiple lines may be used. The amount of halogen or halide solution and the solvent provided by metering pumps 116 and 120 to create the dilute halide in line 125 is either manually preset to a value, or adjusted in real time by the programmable logic control 140 that is coupled to pumps 1 16, 120, or both. The amount of either component in line 125 can be based on monitored process conditions, such as temperatures, flue gas flow, or load.

[0066] Adjusting the flow or the halide or halogen and solvent can control the dilution ratio of the liquid halogen or halide. The dilution ratio can result in the li qui d halogen or halide including any of the wt% values described herein. During startup and/or shutdown of system 100, the amount of solvent in solution from tank 118 used to condition system components (e.g., pumps, transport lines, lances, nozzles) and/or to flush out (purge) components of any halogen or halide solution may be 0 wt% to 100 wt% water 5 wt% to about 99.99 wt%, about 40 wt% to about 60 wt%, about 42 wt% to about 58 wt%, or less than, equal to, or greater than about 5 wt%, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,

37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,

58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,

79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or about 100 wt%. Pumps 116 and 120 can control the rate at which the halide or halogen solution, solvent, or diluted solution of the halide or halogen and solvent are pumped. The rate can be any suitable rate. For example, any liquid may be pumped at a rate of about 0 to about 200gallons per hour (gph), about 0 to about 50 gph, about 0 to about 25 gph, about 0 to about 10 gph, or less than, equal to, or greater than about 0 gph, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,

39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,

60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,

81 , 82, 83, 84, 85, 86, 87, 88. 89, 90, 91. 92, 93, 94, 95, 96. 97, 98, 99. 100, 102.

103. 104, 105. 106, 107, 108, 109, 110, 11 1 , 112, 113, 114, 115, 116, 117, 118,

119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,

135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150,

151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166,

167, 168, 169, 170, 171 , 172, 173, 174, 175, 176, 177, 178, 179, 180, 181 , 182, 183, 184, 185, 186, 187, 188, 189, 190, 191 , 192, 193, 194, 195, 196, 197, 198, 199, or about 200 gph.

[0067] Recirculation line 126 may not be used in normal operation, but can be used for testing and/or to troubleshoot operational problems. Drain 138 may also be provided in the event that system 100 needs to be drained of some/all liquids.

[0068] From line 125, the diluted, or concentrated, liquid halogen or halide solution is supplied to liquid halogen or halide lances 130, which feed into injection point 46. In other embodiments, liquid halogen or halide lance 130 can be instead be a dispersion nozzle, a pipe, an orifice, or a drip-pipe manifold. As shown in FIG. 3, injection points 46 are located at fossil fuel feed zone 12, which allows the halogen or halide solution to be dispensed at any location therein. It is possible to inject the halogen or halide at any other location in system 10 or 10’ using system 100

[0069] FIG. 4 is a schematic depiction of system 100’. System 100’ includes many of the same components as system 100. In addition to the components of system 100, however, system 100’ includes compressed air source 170. Compressed air source 170 can supply compressed air to injection supply line 125 to help push the halide or halogen solution through system 100’. Additionally, compressed air source 170 can supply compressed air directly to liquid halogen or halide lance 130 via line 172 As will be discussed further herein, compressed air supplied directly to liquid halogen or halide lance 130 can function to cool and atomize the liquid halogen or halide to enhance injection into system 10 or 10’. System 100’ shows another possibility for injection points 46 that system 100 or system 100’ can be coupled to. That is, system 100’ is shown coupled to injection points 46 in combustion zone 14.

[0070] FIG. 5 is a schematic depiction of system 100”. System 100” is adapted to deliver solid halogen or halide to the components of combustion system 10. As shown, system 100” delivers solid halogen or halide to fossil fuel feed zone 12. System 100” includes some of the components of systems 100 and 100’. Additionally, system 100” includes solid halide or halogen storage tank 300, fill 302, vent 304, feeder 306, eductor 308, blower 310, control 140, transport line 312. System 100” can include only one of each of these components or any multiple number of the components.

[0071] In operation of system 100”, the solid halide or halogen flows from storage container 300 into feeder 306. Feeder 306 may be configured to be a loss in weight or volumetric mode feeder. The solid halide or halogen can be replenished in storage container 300 through fill 302; vent 304 can help to ensure that storage container 300 remains at or at least does not exceed an optimal internal pressure. Feeder 306 can be equipped with a scale. The scale, in turn, can adjust the speed of feeder 306 in order to help maintain a given (or targeted) mass feed rate. In other embodiments, feeder 306 may he free of a scale, and the speed of feeder 306 may be adjusted to feed a predetermined amount of volume of the solid halogen or halide.

[0072] The predetermined amount of the solid halogen or halide may generally he correlated to a mass feed rate. In some embodiments, to maintain a substantially constant feed, devices such as mechanical agitators and mixers may be included. The feed rate can be set manually to feed a given mass or volume of the solid halogen or halide. Alternatively, the feed rate can be adjusted automatically by control 140 receiving control signals from the plant/process.

For example, feed rates can be adjusted automatically based on monitoring parameters to achieve a predetermined mercury removal, or stack mercury emission. Or, feed rates can be adjusted automatically based on fuel flow, gas flow, generation, or a combination of process parameters. The system 100” may also communicate critical alarms and operating parameters via one- or two-way communication, hardwired or wireless.

[0073] The solid halogen or halide may be supplied through system

100” in one of many suitable manners. For example, as shown in FIG. 5, the solid halogen or halide is metered out of feeder 306 and into eductor 308. At eductor 308, motive air is supplied by blower 310, which propels the solid halogen or halide through transport lines 312 to the injection points 46. In other embodiments, the solid halogen or halide can be supplied through system 100” using a positive pressure system. Solid halogen or halide can be fed through transport line 312 at any suitable rate. For example the rate can be in a range of from about 0-500 pounds per hour (lb/hr), 0-250 pounds per hour (lb/hr), about 0-100 lb/hr, about 0-50 Ib/hr, about 0-25 lb/hr or less than, equal to, or greater than about 0 lb/hr, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 1 10, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165,

170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245,

250, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325,

330, 335, 340, 345, 350, 355, 360, 365, 370, 375, 380, 385, 390, 395, 400, 405,

410, 415, 420, 425, 430, 435, 440, 445, 450, 455, 460, 465, 470, 475, 480, 485,

490, 495, or about 500 Ib/hr. In some embodiments, transport line 312 may be one or more lines, which may be separated, or integrated. To guard against possible leaks, transport line or lines 312 may be insulated, single-walled, double-walled, line-in-line concentrically aligned, or the like. Compressed air may also be provided to assist in transport.. Transport line 312 may include material to withstand corrosion, as needed.

[0074] Heat may be applied to the solid halogen or halide, as well as the components of system 100”, in several suitable manners such as insulating, applying external heat through conductive, convective, and radiant means. Heat can be applied in a continuous or non-continuous manner, controlled manually, or automatically based on preset temperature controls, ambient conditions, and/or process conditions. It may be desirable to monitor the transition zone between the feeder 306 and eductor 308 for parameters such as temperature, pressure, flow, and the like. If desirable, heat may be applied by any mode as needed to maintain or even improve material flow. While only one of each component of system 100” is shown, it should be understood that more than one of any component may be used, in any combination.

[0075] FIG. 6 is a schematic depiction of system 100”’. System 100’” includes many of the same components of system 100” However, system 100’” is configured to deliver the solid halogen or halide to combustion zone 14.

Additionally, system 100’” includes solid halogen or halide lance 400 at injection points 46.

[0076] Although FIGS 3 and 5 as well as FIGS. 4 and 6 show systems

100 and 100” as well as 100’ and 100”’ coupled to components of fossil fuel feed zone 12 and combustion zone 14, respectively, any system can also be coupled to the components of scrubbing zone 16 or discharge zone 18. All of the components described with respect to systems 100, 100’, 100”, and 100”’ can be skid-mounted and provided onsite for ready operation.

[0077] Any of systems 10 and 10’ can include a carbon. In some embodiments the carbon sorbent can be a carbon nanocomposite sorbent. When present, the carbon sorbent can augment or supplement the capture and removal of mercury from the flue gas provided by the halogen or halide alone. Carbon sorbents can include two of more phases such that the phases are intimately connected to each other at nanoscale dimensions (e.g., 1000 nm or less). When these carbon sorbents are highly porous, especially microporous or nanoporous, the intimate connectivity of the two carbon sorbents can result in high surface- areas as well as correspondingly high catalytic activities. This can be the case, for example, when a catalyticai!y active material, such as certain forms of carbon, is dispersed on a bulk substrate having a high surface-area. Carbon sorbents can include a thin layer of graphene sheet coated on or intercalated into an inorganic support. In some embodiments, the carbon sorbent can be about 50% or less carbon, or about 3 wt% to about 50 wt% carbon, or about 5 wt% to about 10 wt% carbon. In some embodiments, the carbon sorbent can be about 1 wt% to about 99.5 wt% bulk substrate, or about 50 wt% to about 97 wt% bulk substrate, or about 90 wt% to about 95 wt% bulk substrate (e.g., diatomaceous earth, smectite clays, and the like).

[0078] The carbon sorbent of the present invention can be any suitable carbon sorbent. In some examples, the sorbent can be a suitable form of carbon distributed on a suitably porous or suitably high surface-area substrate. The carbon sorbent can be produced or can be commercially obtained. In some embodiments, the carbon sorbent is commercially obtained, and further processing steps may be required to suitably activate the carbon for separation of the material, such as separation of the mercury. Further processing steps to suitably activate the carbon sorbent can include treatment with heat (e.g., calcining) or treatment with base. Additional processing can include treatment with the halide or halogen whether in liquid or solid form. Treatment with the halogen or halide can be referred to as“promoting” For example, in some embodiments, treatment of the carbon sorbent with a halide or halogen can promote the carbon sorbent to form active sites in the carbon sorbent which can

99 transform mercury from elemental mercury into oxidized mercury (e.g., mercury oxide). In some embodiments, no promotion of the carbon sorbent is used. For example, in some embodiments, treatment of the carbon sorbent with an acid or base can prepare the carbon sorbent for promotion using a halide or halogen or can prepare the carbon sorbent such that suitable reactivity is obtained. In other embodiments, no treatment with acid or base is used prior to promotion using a halide or halogen or prior to using the sorbent to remove mercury or other materials from the gas.

[0079] The method can include contacting at least part of the carbon sorbent with the material in the gas, such as mercury, to form a composition, such as a mercury-sorbent composition. The present disclosure is not dependent on any particular mechanism of action; so long as the material is removed from the gas using the carbon sorbent, the method is encompassed as an embodiment of the present invention. In some embodiments, the mercury is absorbed in its elemental form by the sorbent; the mercury-sorbent composition can include the sorbent and the elemental form of mercury. In some embodiments, the mercury is converted by the sorbent via a chemical reaction, such as oxidation, such that the mercury from the gas is transformed into an oxide of mercury (e.g., HgO); the mercury-sorbent composition can include the sorbent and a transformed form of the mercury such as a mercury' oxide. In some embodiments, the mercury- sorbent composition can include a combination of elemental mercury and transformed mercury, such as mercury oxide. In some examples, the absorbing of elemental mercury or the transformation of mercury can modify the sorbent, such that the sorbent is at least slightly different after the composition is formed; e.g., after transformation of a particular atom of mercury to mercury oxide, the active location of the sorbent that caused the transformation can be unreactive or less reactive

[0080] In some examples, elemental mercury or transformed mercury can remain absorbed to the sorbent until the mercury-sorbent composition has been removed in a later separation step. For example, elemental mercury or transformed mercury can be absorbed, or reacted and absorbed into or onto the sorbent composition, such that at least about 1 wt%, 3 wt%, 5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 90 wt%, 95 wt%, 96 wt%, 97 wt%, 98 wt%, 99 wt%, 99.9 wt%, 99.99 wt%, or about 99.999 wt% or more of the mercury in the mercury-containing gas stream is absorbed, or reacted and absorbed, into or onto the sorbent composition. In some

embodiments, elemental mercury or transformed mercury can be released from the mercury-sorbent composition; for example, less than about 1 wt%, 3 wt%, 5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 90 wt%, 95 wt%, or less than about 99 wt% of the mercury can be released from the mercury-sorbent composition prior to separation of the mercury-sorbent composition from the gas. In some examples, the majority of absorbed elemental or transformed mercury can remain part of the mercury-sorbent composition until the mercury-sorbent composition is removed in a later separation step. In some examples, transformed mercury that is released from the mercury-sorbent composition can be later removed from the gas via the separation step. In some examples, elemental or transformed mercury that has been released from the mercury-sorbent composition can contact carbon sorbent to form a mercury- sorbent composition, to be removed later via the separation step.

[0081] In various embodiments, the carbon sorbent includes binding sites that bind with mercury in the mercury-containing gas. In some examples, the sorbent material includes carbon that is reacted or impregnated with halogens or halides to form mercury binding sites in the promoted sorbent. In some examples, the sorbent material can include carbon that is activated at least in part by treatment with a base, wherein the base-activated carbon can react or become impregnated with the halogens or halides described herein. In some

embodiments, the binding sites in the carbon react with mercury in the mercury- containing gas to form the mercury-sorbent composition. In some examples, at least a portion of the binding sites of the carbon react with oxidized mercury _' in the mercury-containing gas to form a mercury-sorbent composition.

[0082] In some embodiments, at least some of the carbon in the carbon sorbent is in the graphene form of carbon. The graphene form of carbon can, in some embodiments, include higher concentrations of locations suitable as the active sites of the carbon sorbent. In some examples, certain parts of graphene carbon can have the highest concentrations of locations suitable as the active sites of the carbon sorbent: in some examples at the edges, in some examples in non-edge locations. Such locations suitable as active sites may be activated via treatment with halide or halogen, as described herein. In various embodiments, the carbon in the carbon sorbent can be at least about 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 90 wt%, 95 wt%, 96 wt¾, 97 wt%, 98 wt%, 99 wt%, 99.9 wt%, 99.99 wt%, or more than about 99.999 wt% graphene form of carbon.

[0083] In some embodiments, the carbon sorbent has a mean particle diameter greater than 40 micrometers, or greater than 60 micrometers, or a particle size distribution greater than that of fly ash or entrained ash in a flue gas stream to be treated, such that the carbon sorbent and ash can be separated by physical means in the separation step.

[0084] In one embodiment, the carbon sorbent can be a. carbon sorbent that is promoted for gas-phase Hg oxidation when a halide salt contained in the porous structure is decomposed during injection into a heated duct. In some embodiments, the halide salt can be ammonium bromide. In some embodiments, the carbon sorbent can include graphene. In some examples, the non-carbon part of the carbon sorbent includes a high surface-area, porous, inorganic matrix.

[0085] Where employed a method for reducing the mercury content of a mercury-containing gas using the carbon sorbent in any of systems 10 or 10’ can include promoting at least a portion of the sorbent material with the halogen or halide. The promoting of the sorbent material includes chemically reacting or impregnating the portion of the sorbent material with the halogen or halide promoter. The halogen or halide promoter can be derived from reaction or degradation of another compound (e.g., a promoter precursor).

[0086] The promoting of the sorbent material gives a promoted sorbent.

The promoting of the sorbent material can occur before injection into a gas stream, during injection into a gas stream, after injection into a gas stream, or a combination thereof, wherein the gas stream can be a mercury-containing gas stream, a transport stream, or a combination thereof. In some examples, the promoter can be added to the sorbent before the promoter and the sorbent react, such that the heat of the gas stream into which the promoter is added causes the promoting of the sorbent. For example, the promoter can be added as a gas, as a gas dissolved in a liquid, or as a solid such as a salt, or other substance (e.g., acid) dissolved in liquid (e.g., water). In examples in which the promoter is added in a liquid such as water, the water can be allowed to dry, which can allow the promoter to adhere to, impregnate, or react with the sorbent, or a

combination thereof. In some examples, a pre-added promoter can be an ammonium salt, such as an ammonium chloride, an ammonium bromide, or an ammonium iodide, including, for example, mono-, di-, tri-, or tetraalkyl ammonium halides, orNH ⁺ halide salts. In some examples, the promoter can be added to the sorbent near to or at the time of promoting; for example, the promoter can be added to a gas stream with the sorbent or such that it contacts the sorbent within a heated gas stream, such as a mercury-containing gas stream or a feed gas stream. In some examples, the promoter can be NH Br.

[0087] In some examples the carbon sorbent can include a nitrogen or nitrogenous component. The concentration of nitrogen in a surface layer of an individual sorbent particle can be at least one of 1) higher than the concentration of nitrogen in a core of the sorbent panicles and 2) higher than the concentration of nitrogen in the carbon sorbent material from which the carbon sorbent was derived. The surface layer of each particle can independently be continuous (e.g., unbroken, with minimal or no gaps) or non-continuous. The surface layer can be at the outer surface of the particle. The surface layer of each particle can independently have any suitable thickness. The surface layer can have a variable thickness, or can have a substantially consistent thickness. In some

embodiments, the surface layer can have a thickness of about 0.000001% to about 99.99% of the radius of the particle, 0.001% to 99%, 0.001% to about 50%, 1% to about 50%, 0.1% to 25%, or about 25% to 50% of the radius of the particle. If the particle is non-spherical the radius can be estimated as about one- half of the largest dimension of the particle.

[0088] In some embodiments, each carbon sorbent can independently include about 1.001 times higher nitrogen concentration in a surface layer of the individual particle than in the core of the particle or less, or about 1.01, 1.1, 1.2, 1.4, 1.6, 1.8, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 50, 100, or about 1000 times higher nitrogen concentration in the surface layer than in the core. In some

embodiments, the concentration of nitrogen in the surface layer can be about

0.000001 wt % or less, or about 0.001, 0.01, 0.1 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, or about 90 wt % or more nitrogen in some examples, the concentration of nitrogen in the surface layer can be about 0.001 wt %-99 wt % nitrogen, 5 wt %-8Q wi %, or about 5-60 wt %. In various embodiments, the concentration of nitrogen in the core can be about 0 wt ¾, 0.000001, or about 0.001 , 0.01 , 0.1 , 1 , 2, 3, 4, 5, 10, 15, 20, 50, or 90 wt % or more. In some examples, the concentration of nitrogen in the core can be about 0.001 wt %-99 wt % nitrogen, 0.1 wt %~20 wt % or about 1 wt %-6 wt %.

[0089] The nitrogen or nitrogenous source can include an ammonium salt, indole, quinoxaline, isoquinoline, piperazine, quinolone,

diazabicyclo[2 2.2]octane (DABCO), polyvinylpyrrolidone, vinylpyrrolidone- vinyl acetate copolymer, vinylpyrrolidone-acrylic acid copolymer,

vinylpyrrolidone-maleic acid copolymer, or a combination thereof.

[0090] The carbon sorbent can include a graphene edge including an active site for mercury' oxidation and a nitrogen layer structure including cationic nitrogen atoms, neutral nitrogen atoms, or a combination thereof, the nitrogen layer structure being proximate the active site. The graphene edge is part of the carbon in the sorbent. Some or all of the nitrogen in the sorbent or the surface layer thereof can be a part of the nitrogen layer structure. The basic nitrogen atoms in the nitrogen layer structure can react with acid gases (e.g., S0 _3, H ₂ S0 ₄ , and the like) in the mercury-containing gas, at least partially preventing them from reacting with the active site. The cationic nitrogen atoms in the nitrogen layer structure can polarize an electron field in the graphene edge thereby increasing oxidation potential (e.g., mercury oxidation potential) of the active site.

[0091] The nitrogen layer structure (e.g., nitrogen lattice) can be a structure comprising cationic nitrogen atoms and neutral nitrogen atoms, optionally including negatively charged atoms, and that is permeable to gaseous pollutants, such as mercury, and surrounds, covers, or is near to the active site (e.g., oxidation site) on the graphene edge structure. The nitrogen layer structure may be attached in some fashion (e.g., via bonds or electrostatic attraction) to the sorbent surface, but is not identical to the carbon surface structure. The nitrogen layer structure can be a structure where a portion of the total nitrogen includes nitrogen cations (nitrogen bearing a positive charge) owing to tetravalent valency, with nitrogen bonded to 4 other atoms as with an ammonium ion (typically formed from an amine or ammonia) or nitrogen bonded to 3 other atoms but possessing a double bond as the imminium ion (typically formed from a heterocyclic). Both cationic nitrogen atoms, neutral nitrogen atoms, or a combinati on thereof in the nitrogen layer structure can contribute to enhanced activity for mercury capture by both capturing S0 ₃ and its products H ₂ S0 ₄ and HS0 ₄ , which are detrimental to Hg capture, within the nitrogen layer structure, and increasing the electron accepting character (oxidation potential) of the proximate active oxidation site in the graphene layer of the sorbent.

[0092] The nitrogen in the sorbent can be derived from any nitrogen- containing compound, such as a nitrogen-containing organic or inorganic compound, such as by pyrolysis or carbonization. In some examples, the nitrogen is derived from or part of any nitrogen-containing heterocycle, or from any other nitrogen-containing compound. For example, the nitrogen can be derived from indole, quinoxaline, carbazole, isoquinoline, piperazine, quinolone, quinoxaline, diazabicyclooctane, polyacrylonitrile, polyvinylpyrrolidone, vinylpyrrolidone- vinyl acetate copolymer, vinylpyrrolidone-acrylic acid copolymer, vinylpyrrolidone-maleic acid copolymer, polyethylenimine, an amine, an amino acid (e.g., alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, or valine), anaiine, nitrobenzene, hydroxylamine, urea, hydrazine, sulfamic acid, nitriles, carbamates, isocyanates, urethanes, or a combination thereof. In some examples, the nitrogen in the sorbent can be derived from or part of a nitrogen- containing inorganic compound, such as ammonia, ammonium bromide, ammonium chloride, nitric acid, nitrous acid, nitrogen dioxide, compounds including N0 ₃ , compounds including NO _? ., and the like. The nitrogen-containing inorganic compound can be such as an ammonium halide, a methylammonium halide, an ammonium salt of an oxyacid of a Group VI element, an ammonium salt of an oxyacid of a Group V element, or a combination thereof. The nitrogen- containing inorganic compound can be ammonium bromide, ammonium iodide, ammonium chloride, an organic halide with a formula of CH3NH3X (wherein X is Cl, Br or I), ammonium sulfate, ammonium hydrogen sulfate, ammonium sulfite, ammonium hydrogen sulfite, ammonium persulfate, ammonium pyrosulfate, ammonium thiosulphate, ammonium dithionite, ammonium aluminium sulfate, ammonium iron sulfate, ammonium sulfamate, ammonium phosphate, diammonium phosphate, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, ammoniu thiophosate, ammoniu nitrate, ammonium nitrite, ammonium carbonate, ammonium thiocyanate, ammonium sulfide, ammonium hydrogen sulfide, ammonium acetate, ammoniu

carbamate, ammonium carbonate, ammonium chlorate, ammonium chromate, ammonium fluoride, ammonium formate, ammonium hydroxide, ammonium perchlorate, sodium nitrite, sodium nitrate, lithium nitrite, lithium nitrate, barium nitrite, barium nitrate, cerium nitrite, cerium nitrate, FeNH ₄ (S0 ₄ ) ₂ ,

1· c( X i I ! ) ;( S< ⁾ ) ·. FeNH ₄ Br ₄ , FeNEUC , A1NH ₄ (S0 ₄ )2, hydrates thereof or a combination thereof. The nitrogen-containing inorganic compound can be ammonium sulfate ((NH ₄ ) S0 ₄ ), ammonium bromide (NH ₄ Br), ammonium iodide (NH ₄ I), ammonium chloride (NH ₄ C1), ammonium fluoride (NH ₄ F), ammonium thiosulfate ((NH ₄ ) ₂ S ₂ 0 ₃ ), ammonium bisulfate (MT ₄ S0 ₄ H), or a combination thereof.

[0093] The carbon sorbent whether including nitrogen or not can be prepared in-flight. For example, the carbon of the resulting carbon sorbent can be contacted with the promoter, nitrogen, or mixture thereof while in the mercury-containing gas or at any other location in systems 10 or 10’.

[0094] As described herein, system 100 or 100’ may include liquid halogen or halide lance 130. FIG. 7 A is a sectional view of an embodiment of liquid halogen or halide lance 130, FIG. 7B is a sectional view of liquid halogen or halide lance 130 taken along line A-A of FIG. 7 A, FIG. 7C is a secti onal view of liquid halogen or halide lance 130 rotated 90 degrees relative to FIG. 7A, and FIG. 7D is a sectional view of liquid halogen or halide lance 130 taken along line B-B of FIG. 7C. FIGS. 7A-7D show many of the same components and will, therefore, be discussed concurrently.

[0095] As shown in FIGS. 7A-7D, liquid halogen or halide lance 130 includes first end 200, second end 202, shell 204, opening 205, halogen or halide channel 206, halogen or halide channel inlet 203, halogen or halide channel outlet 207, first compressed air channel 208, first compressed air channel inlet 21 1 , first compressed air channel closed end 213, first compressed air channel perforations 209, second compressed air channel 210, second compressed air channel closed end 230, second compressed air channel open end 232, second compressed air channel perforations 215, nozzle 212, interstitial space 214, collar 216, and indexing pin 218.

[0096] Shell 204 extends between first end 200 and second end 202.

Halogen or halide channel 206, first compressed air channel 208, and second compressed air channel 210 are dispersed within shell 204 with interstitial space 214 defined therebetween. Halogen or halide channel 206 extends from halogen or halide channel inlet 203 located proximate to first end 200 to halogen or halide outlet 207 proximate to second end 202. First compressed air channel 208 extends between first compressed air channel inlet 232 proximate to first end 200; to first compressed air channel closed end 230 proximate to second end 202. First compressed air channel perforations 215 are located about first compressed air channel inlet 211. Second compressed air channel 210 extends from second compressed air channel closed end 230 proximate to first end 200 to second compressed air channel outlet 232 located proximate; to second end 202. Second compressed air channel perforations 215 are disposed between second compressed air channel closed end 21 1 230 second compressed air channel outlet 232. Nozzle 212 is attached to shell 204 proximate to opening 205. Collar 216 can be affixed to shell 204 and include indexing pin 218.

[0097] In operation, the liquid halogen or halide is fed to halogen or halide channel 206 through either system 100 or 100’. The halogen or halide exits liquid halogen or halide lance 130 through nozzle 212. At the same time compressed air is supplied to first compressed air channel 208 Compressed air is discharged from compressed air channel 208 through perforations 209. The compressed air then circulates through interstitial space 214 and eventually enters second compressed air channel through second compressed air channel perforations 215. Perforations 209 and 215 can be spaced at any suitable distance with respect to each other, relative to first end 200 and second end 202. The greater the distance between perforations 209 and 215 is, the more the compressed air is allowed to circulate through interstitial space 214. Circulation of compressed air through interstitial space 214 can serve to cool nozzle 212. This can be helpful in many different embodiments. For example, it can be helpful in embodiments where nozzle 212 is disposed within an injection point 46 located at boiler 28 where nozzle 212 will be exposed to significantly high temperatures. Collar 216 and indexing pin 218 can help to secure and position nozzle 212 within injection point 46, so as to direct flow of dispersed halogen or halide, and minimize, or substantially eliminate, wall impingement.

[0098] After entering perforations 215, compressed air then passes through second compressed air channel 210 and exits through second

compressed air channel outlet 232. As the compressed air exits second compressed air channel 210 it interacts with halogen or halide exiting halogen or halide channel 206. The compressed air can serve to atomize the liquid halogen or halide.

[0099] FIG. 8 A is a sectional view of an embodiment of liquid halogen or halide lance 130’, FIG. 8B is a sectional view of liquid halogen or halide lance 130’ taken along line A-A of FIG. 8A, FIG. 8C is a sectional view of liquid halogen or halide lance 130’ rotated 90 degrees relative to FIG. 8 A, and FIG. 8D is a sectional view of liquid halogen or halide lance 130’ taken along line B-B of FIG. 8C. FIGS. 8A-8D show many of the same components and will, therefore, be discussed concurrently.

[00100] As shown in FIGS. 8A-8D, liquid halogen or halide lance 130’ includes first end 500, second end 502, shell 504, opening 505, compressed air channel 506, compressed air channel inlet 503, compressed air channel outlet 507, first halogen or halide channel 508, first halogen or halide channel inlet 511, first halogen or halide channel closed end 513, first halogen or halide channel perforations 509, second halogen or halide channel 510, second halogen or halide channel closed end 531, second halogen or halide channel open end 533, second halogen or halide channel perforations 515, nozzle 512, interstitial space 514, collar 516, and indexing pin 518.

[00101] Shell 504 extends between first end 500 and second end 502. Compressed air channel 506, first halogen or halide channel 508, and second halogen or halide channel 510 are dispersed within shell 504 with interstitial space 514 defined therebetween. Compressed air channel 506 extends from compressed air channel inlet 503 located proximate to first end 500 to halogen or halide outlet 507 proximate to second end 502 First halogen or halide channel 508 extends between first halogen or halide channel inlet 511 proximate to first end 500 to first halogen or halide channel closed end 531 proximate to second end 502. First halogen or halide channel perforations 515 are located about first halogen or halide channel 51 1. Second halogen or halide channel 510 extends from second halogen or halide channel closed end 531 proximate to first end 500 to second halogen or halide channel outlet 533 located proximate to second end 502. Second halogen or halide channel perforations 515 are disposed between second halogen or halide channel closed end 531 and second halogen or halide channel outlet 533. Nozzle 512 is attached to shell 504 proximate to opening 525. Collar 516 can be affixed to shell 504 and include indexing pin 518. Collar 516 and indexing pin 518 can help to secure and position nozzle 512 within injection point 46.

[00102] In operation, the compressed air is fed to compressed air channel 506 through either system 100 or 100’. The compressed air exits liquid halogen or halide lance 130’ through nozzle 512. At the same time, the liquid halogen or halide is supplied to first halogen or halide channel 508. The halogen or halide is discharged from halogen or halide channel 508 through perforations 509. The halogen or halide then circulates through interstitial space 514 and eventually enters second halogen or halide channel 510 through second halogen or halide channel perforations 515. Perforations 509 and 515 can be spaced at any suitable distance with respect to each other, relative to first end 500 and second end 502. The greater the distance between perforations 509 and 515 is, the more the halogen or halide is allowed to circulate through interstitial space 514.

Circulation of halogen or halide through interstitial space 514 can serve to cool nozzle 130’. This can be helpful in many different embodiments. For example, it can be helpful in embodiments where nozzle 130’ is disposed within an injection point 46 located at boiler 28 wdiere nozzle 130’ will be exposed to significantly high temperatures.

[00103] After entering perforations 515, halogen or halide then passes through second halogen or halide channel 510 and exits through second halogen or halide channel outlet 533 As the halogen or halide exits second halogen or halide channel 510, it interacts with compressed air exiting compressed air

3? channel 506. The compressed air can serve to atomize the liquid halogen or halide.

[00104] In either liquid halogen or halide lance 130 or liquid halogen or halide lance 130’, nozzle 212 or 512 respectively can be configured to pivot. For example, nozzle 212 or 512 can pivot in a range of from about 90 degrees to about 180 degrees relative to an axis passing through first ends 200 or 500 and second ends 202 or 502, about 50 degrees to about 100 degrees, or less than, equal to, or greater than about 90 degrees, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, or about 180 degrees. Additionally, either liquid halogen or halide lance 130 or 130’ can be rotated about the aforementioned axis to any suitable degree. The ability to pivot nozzle 212 or 512 and/or rotate liquid halogen or halide lance 130 or 130’ can be helpful in that the location to which the halide or halogen can be dispensed can be precisely controlled. For example, the halide or halogen can be dispensed substantially in-line with a flow ^? of flue gas through system 100 or 100’. In some embodiments, nozzle 212 or 512 can pivot, and optionally rotate, across a range of degrees to enhance dispersion of the halide or halogen within the boiler, so as to direct flow of dispersed halogen or halide, and minimize, or substantially eliminate, wall impingement, or on a supply of coal .

[00105] As described herein, system 100” or 100’” may include solid halogen or halide lance 400. FIG 9A is a sectional view of solid halogen or halide lance 400, and FIG. 9B is an exploded view of solid halogen or halide lance 400. Solid halogen or halide lance 400 includes shell 402 Shell 402 can be one piece or multiple pieces. For example, solid halogen or halide lance 400 is shown where shell 402 includes first piece 404, second piece 406, and third piece 408. Solid halogen or halide lance 400 also includes dispersion head 411. Dispersion head 41 1 is at least partially disposed within shell 402. Dispersion head 408 can be threadingly engaged with shell 402. Either of shell 402, dispersion head 408, or both may include a high-grade steel alloy, a refractory metal, or a combination thereof. Examples of high-grade steel alloys may include stainless steels such as SS309 or SS310. Examples of refractory metals can include molybdenum, tungsten, niobium, tantalum, rhenium, and alloys thereof. In general, the high-grade steel alloy or refractory metal are capable of withstanding temperatures found in a boiler in systems 100 or 100’. The temperature may, for example, range from about 260 °C to about 5600 °C, about 500 °C to about 4000 °C, about 1000 °C to about 2000 °C, or less than, equal to, or greater than about 260 °C, 500, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, or 5600 °C. In some embodiments, dispersion head 411 many include a different material than shell 402. For example, dispersion head 411 may include a material that is capable of degrading when exposed to heat. The ability of dispersion head 408 to degrade can make it easier to replace dispersion head 411 during operation. In some embodiments, a material such as the high- grade stainless steel alloy or refractory metal may be configured as a liner to which the degradable material is applied to help prevent total degradation of dispersion head 41 1

[00106] In operation, dispersion head 408 is disposed at least partially within injection point 46 The solid halide or halogen flows to lance 400 by way of systems 100” and 100’”. Solid halogen or halide lance 400 can be secured within injection point 46 in many suitable ways. For example, FIG. 10 is a sectional view of solid dispersion lance 400 disposed in injection point 46, which is adapted as a bore in door 418 of boiler 28. To aide in securing solid dispersion lance 400 in injection point 46, collar 420 can be included to circumscribe solid dispersion lance 400. Collar 420 is also affixed to an exterior surface of door 418. Door 418 may be a door of a Combustion Engineering (CE) manufactured boiler.

[00107] FIG. 11 is a sectional view of solid dispersion lance 400 disposed in injection point 46, which is adapted as a bore in door 418 of boiler 28. To aide in securing solid dispersion lance 400 in injection point 46, collar 420 can be included to circumscribe solid dispersion lance 400. Collar 420 is also affixed to an exterior surface of door 418’ Collar 420 further includes ear 422, which overlays a perimeter of door 418’. Door 418’ may be a door of a combustion engineering boiler. Door 418’ may be a door of a Babcock and Wilcox (B&W) manufactured boiler.

[00108] FIG. 12 is a sectional view of solid dispersion lance 400 disposed in injection point 46, which is adapted as a bore in wall 424 of boiler 28 To aide in securing solid dispersion lance 400 in injection point 46, collar 420 can be included to circumscribe solid dispersion lance 400. Struts 426 can be used to strengthen the connection between collar 420 and solid dispersion lance 400. Collar 420 is also affixed to an exterior surface of the wall 424.

[00109] Although FIGs. 11 and 12 show doors of a Combustion

Engineering and Babcock and Wilcox manufactured boiler respectively, a door of any other boiler is contemplated by the disclosure. Examples of other manufacturers include Foster Wheeler and Riley Stoker

[00110] As described herein, the design of lances 130, 130’, and 400 can make those lances suitable for use in many different systems. Although the lances 13, 130’, and 400 offer several advantages, in alternative embodiments of the systems described herein, an alternative suitable lance may include as few as one halide or halogen channel that is adapted to transport the halide or halogen to the injection point. The alternative suitable lance can further include as few as one air channel for delivering an atomizing source of air such as compressed air to the lance to interact with the halide or halogen.

Additional Embodiments.

[00111] The following exemplary embodiments are provided, the numbering of which is not to be construed as designating levels of importance:

[00112] Embodiment 1 provides a system for separating mercury from a mercury-containing gas, the system comprising:

a coal-feed zone;

a combustion zone located downstream of the coal feed zone to receive a supply of coal from the coal-feed zone and to combust at least a portion of the supply of coal and produce the mercury-containing gas,

a scrubbing zone located downstream of the combustion zone for receiving the mercury-containing gas and rem oving at least a portion of the mercury from the mercury-containing gas;

a supply of a halide or halogen for injecting or adding to the system; and one or more halide or halogen injection points for injecting the halide or halogen, the halide or halogen injection points located at least one of at, upstream, and downstream of at least one of the coal-feed zone, the combustion zone, and the scrubbing zone. [00113] Embodiment 2 provides the system of Embodiment 1, wherein the coal-feed zone comprises a coal bunker, a coal feeder, a coal pulverizer, or combinations thereof.

[00114] Embodiment 3 provides the system of Embodiment 2, wherein the one or more halide or halogen injection points are located at least one of at, upstream, and downstream of at least one of the coal bunker, the coal feeder, or the coal pulverizer, or combinations thereof.

[00115] Embodiment 4 provides the system of any one of Embodiments 1-3, further comprising coal in the coal-feed zone.

[00116] Embodiment 5 provides the system of Embodiment 4, wherein at least a portion of the coal is substantially pulverized.

[00117] Embodiment 6 provides the system of any one of Embodiments 4 or 5, wherein at least a portion of the coal is contacted with the halide or halogen

[001 8] Embodiment 7 provides the system of any one of Embodiments 1-6, wherein the halide or halogen is chosen from HC!, HBr, HI, Br>, Ch, I ₂ , BrCl, IBr, IC1, C1F, PBr ₃ , PC1 ₅ , SC , CuCh, CuBr ₂ , Al ₂ Br ₆ , Fel _x , FeBr _y , Fei ^' L MnBr ₂ , MnCh, NiBr ₂ , NiCh, Nil , ZnBr ₂ , ZnCl ₂ , Znl ₂ , NH ₄ Br, Nl hCL NEW, NH ₄ F, FeNH ₄ Br ₄ , FeNH ₄ C! _4, F ₂ , F , CF Br , G, NH ₄ Br, NaBr, CaBr ₂ , NaCl, CaCh, NH ₄ C1, NH4I, Nal, Cal ··. KI, KCl, HI, M I A, NaF, CaF ₂ , HF, LiBr, AgCl, AgBr, CHI ;, CH iBr, AuBr, MgBr ₂ , MgCl ₂ , hydrates thereof, and combinations thereof wherein x, y, and z are independently 1, 2, 3, or 4.

[00119] Embodiment 8 provides the system of any one of Embodiments 1-7, wherein the halide or halogen is a liquid, gas, or solid.

[00120] Embodiment 9 provides the system of Embodiment 8, wherein the halide or halogen is a solid and is mixed with, an alkali, a clay, a metal, or a combination thereof

[00121] Embodiment 10 provides the system of Embodiment 8, wherein the alkali is chosen from limestone, lime, a carbonate, and combinations thereof.

[00122] Embodiment 11 provides the system of Embodiment 8, wherein the clay is chosen from kolinite, dickite, halioysite, nacrite, montmoriilonite, nontronite, beidellite, sepiolite, attapulgite, bentonite, and mixtures thereof. [00123] Embodiment 12 provides the system of Embodiment 8, wherein the metal is gold, silver, platinum, palladium, iron, lead, nickel, copper, zinc, aluminum, tin, manganese, magnesium, and oxides thereof

[00124] Embodiment 13 provides the system of any one of Embodiments 9-12, wherein the halide or halogen is further mixed with a flow' agent.

[00125] Embodiment 14 provides the system of Embodiment 13, wherein the flow agent is chosen from silica, alumina, metal, and combinations thereof.

[00126] Embodiment 15 provides the system of any one of Embodiments 9-14, wherein the halide or halogen is in a range of from about 5 wt% to about 100 wt% of the halide or halogen.

[00127] Embodiment 16 provides the system of any one of Embodiments 1-15, wherein the combustion zone comprises a boiler furnace.

[00128] Embodiment 17 provides the system of any one of Embodiments 1-16, wherein a temperature in the combustion zone is sufficient to combust at least a portion of the supply of coal.

[00129] Embodiment 18 provides the system of any one of Embodiments 16-17, wherein the combustion zone comprises a boiler having one or more temperature regions.

[00130] Embodiment 19 provides the system of Embodiment 18, wherein at least one of the halide or halogen injection points is located at one or more of the temperature regions.

[00131] Embodiment 20 provides the system of any one of Embodiments 16-19 wherein the boiler comprises a door and the halide or halogen injection point is located thereon.

[00132] Embodiment 21 provides the system of any one of Embodiments 16-20 wherein the boiler comprises a wall and the halide or halogen injection point is located thereon.

[00133] Embodiment 22 provides the system of any one of Embodiments 1-21, wherein the scrubbing zone comprises a scrubber.

[00134] Embodiment 23 provides the system of Embodiment 22, wherein the scrubber is chosen from a wet scrubber, a dry flue gas desulfurization system, a SO _?., NOx, HC1, a particulate removal device, mercury' scrubbing system, and combinations thereof. [00135] Embodiment 24 provides the system of Embodiment 23, wherein the scrubber is a wet scrubber comprising one or more spray nozzles for dispensing a scrubbing solution.

[00136] Embodiment 25 provides the system of Embodiment 24, wherein the halide or halogen injection points are located at the spray nozzle.

[00137] Embodiment 26 provides the system of Embodiment 24, wherein the scrubbing solution is supplied to the one or more spray nozzles by a scrubbing solution supply system and one or more of the halide or halogen injection points are located at least one of at, upstream, and downstream of the scrubbing solution supply system.

[00138] Embodiment 27 provides the system of Embodiment 23, wherein the scrubber is a dry scrubber and the dry scrubber is chosen from a dry sorbent injection system and a spray dryer absorber.

[00139] Embodiment 28 provides the system of any one of Embodiments 1-27, wherein the one or more halide or halogen injection points are located at least one of at and downstream of the scrubber.

[00140] Embodiment 29 provides the system of any one of Embodiments 1-28, further comprising an air preheater, an electrostatic precipitator, a baghouse filter, or a combination thereof.

[00141] Embodiment 30 provides the system of Embodiment 29, wherein the one or more halide or halogen injection points are located at least one of at, upstream, and downstream of at least one of the air preheater, the electrostatic precipitator, and the baghouse filter.

[00142] Embodiment 31 provides the system of any one of Embodiments 29 or 30, wherein the scrubbing zone is located upstream or downstream of at least one of the air preheater, the electrostatic precipitator, and the baghouse filter.

[00143] Embodiment 32 provides the system of any one of Embodiments 1-31, wherein the one or more halide or halogen injection points are coupled to one or more injection systems.

[00144] Embodiment 33 provides the system of Embodiment 32, wherein the one or more injection systems comprise: at least one of a liquid dispersion lance, a solid dispersion lance, a dispersion nozzle, an orifice, and a drip-pipe manifold, coupled to a halide or halogen injection point, and

a halide or halogen supply in flow communication with the liquid or sold dispersion lance, the dispersion nozzle, the orifice, the drip-pipe manifold, or combinations thereof.

[00145] Embodiment 34 provides the system of Embodiment 33, wherein the liquid dispersion lance atomizes a solution flowing therethrough.

[00146] Embodiment 35 provides the system of Embodiment 33, wherein the halide or halogen storage tank stores a solid halide or halogen.

[00147] Embodiment 36 provides the system of Embodiment 35, wherein the storage tank comprises a dehumidifier, a supply of dehumidified air, a vibration device, an aeration device, a heater, or a combination thereof.

[00148] Embodiment 37 provides the system of Embodiment 33, wherein the one or more injection systems further comprise:

a diluent supply, and

a halogen or halide and diluent mixing location located downstream of the halide or halogen storage tank and the diluent supply system and upstream of the liquid dispersion lance or the solid dispersion lance.

[00149] Embodiment 38 provides the system of Embodiment 37, further comprising:

a diluent metering valve located downstream of the diluent supply system and upstream of the halogen or halide and diluent mixing location; and

a halogen or halide metering valve located downstream of the halide or halogen storage tank and upstream of the mixing location.

[00150] Embodiment 39 provides the system of any one of Embodiments 37 or 38, wherein the diluent is chosen from water, an organic solvent, a polar mixture of the water and organic solvent, or a nonpolar mixture of the water and organic solvent, and combinations thereof.

[00151] Embodiment 40 provides the system of any one of Embodiments 37, wherein a diluted halogen or halide solution is produced at the mixing location. [00152] Embodiment 41 provides the system of Embodiment 40, wherein the diluted halogen or halide comprises from about 20 wt% to about 70 wt% halogen or halide

[00153] Embodiment 42 provides the system of Embodiment 40, wherein the diluted halogen or halide comprises from about 42 wt% to about 58 wt% halogen or halide.

[00154] Embodiment 43 provides the system of any one of Embodiments 33-42, further comprising a compressed air supply upstream of and in flow communication with the liquid dispersion lance or the solid dispersion lance.

[00155] Embodiment 44 provides the system of any one of Embodiments 33-43, wherein the liquid dispersion lance comprises:

a shell extending from first and second opposed ends;

a halogen or halide channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first compressed air channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end; and

a second compressed air channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[00156] Embodiment 45 provides the system of Embodiment 44, further comprising a nozzle attached to a second end and in flow communication with the outlet of the halogen or halide channel and the outlet of the second compressed air channel.

[00157] Embodiment 46 provides the system of Embodiment 45, wherein the nozzle pivots in a range of from about 90 degrees to about 180 degrees relative to an axis extending from the first end to the second end.

[00158] Embodiment 47 provides the system of any one of Embodiments 44-46, wherein the perforations of the first compressed air channel are configured to deliver compressed air from the first compressed air channel to at least a portion of the perforations of the second compressed air channel and to an interstitial volume of the nozzle. [00159] Embodiment 48 provides the system of any one of Embodiments 33-47, wherein the liquid dispersion lance comprises:

a shell extending from first and second opposed ends;

a compressed air channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first halogen or halide channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end; and

a second halogen or halide channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[00160] Embodiment 49 provides the system of Embodiment 44, further comprising a nozzle attached to the second end and in flow communication with the outlet of the compressed air channel and the outlet of the second halogen or halide channel.

[00161] Embodiment 50 provides the system of Embodiment 45, wherein the nozzle is configured to pivot in a range of from about 90 degrees to about 180 degrees relative to an axis extending from the first end to the second end.

[00162] Embodiment 51 provides the system of any one of Embodiments 44-50, wherein the perforations of the first halogen or halide channel are configured to deliver the halogen or halide from the first halogen or halide channel to at least a portion of the perforations of the second halogen or halide channel and to an interstitial volume of the nozzle between the first compressed air channel, first halogen or halide channel, second halogen or halide channel, and the shell.

[00163] Embodiment 52 provides the system of Embodiment 33, wherein the solid dispersion lance comprises:

a shell extending from first and second opposed ends; and

a dispersion head at least partially disposed within the shell and adapted to dispense the solid halogen or halide through the halide or halogen injection point.

[00164] Embodiment 53 provides the system of Embodiment 52, wherein the dispersion head is threadingly engaged with the shell. [00165] Embodiment 54 provides the system of any one of Embodiments 52 or 53, wherein at least one of the shell and the dispersion head comprise a steel alloy, a refractory metal, or a mixture thereof

[00166] Embodiment 55 provides the system of any one of Embodiments 52-54, wherein the dispersion head comprises a material configured to degrade upon exposure to heat.

[00167] Embodiment 56 provides the system of any one of Embodiments 52-55, wherein the shell includes a thread disposed on an external surface.

[00168] Embodiment 57 provides the system of any one of Embodiments 52-56, wherein the shell is threadingly engaged with the injection point.

[00169] Embodiment 58 provides the system of any one of Embodiments 32-57, wherein the one or more injection systems are reversibly coupled to the one or more injection points.

[00170] Embodiment 59 provides the system of Embodiment 58, wherein components of the one or more injection system are skid-mounted.

[00171] Embodiment 60 provides the system of any one of clams 1-59, wherein,

the coal-feed zone comprises a coal bunker, a coal feeder, and a coal pulverizer;

the scrubbing zone comprises a scrubbing device chosen from a NOx removal device, a S0 ₂ removal device, a S0 ₃ removal device, a Hg removal device, a HC1 removal device, a particulate removal device, a wet scrubber, a dry' scrubber, and combinations thereof;

the halide or halogen is a liquid comprising HC1, HBr, EH, Br ₂ , Cl ₂ , h, BrC!, IBr, IC1, C1F, PBr ₃ , PCk SCh, CuCk CuBr ₂ , Al ₂ Br ₆ , ! ek FeBr _y , FeCk MnBr ₂ , MnCh, iBr ₂ , MCE, Nii ₂ , ZnBr ₂ , ZnCl ₂ , Znl ₂ , NH ₄ Br, M FC!. NEW, M l ;!· ^· . FeNH ₄ Br ₄ , FeNFECU, F _¾ F , Cl Br , G, NFI Br, NaBr, CaBr ₂ , Nad, CaCl ₂ , M FC!. NEW, Nal, Cal ₂ , KI, KC1, HI, M i d·, NaF, CaF ₂ , HF, LiBr, AgCl, AgBr, CHE, CH ₃ Br, AuBr, MgBr ₂ , MgCE, hydrates thereof, or combinations thereof wherein x, y, and z are independently 1, 2, 3, or 4; and

the one or more halide or halogen injection points are reversibly coupled to the liquid dispersion lance comprising:

a shell extending from first and second opposed ends; a halogen or halide channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first compressed air channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end, and

a second compressed air channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[00172] Embodiment 61 provides the system of any one of clams 1-59, wherein,

the coal-feed zone comprises a coal bunker, a coal feeder, and a coal pulverizer;

the scrubbing zone comprises a scrubbing device chosen from a NOx removal device, a SO removal device, a S0 ₃ removal device, a Hg removal device, a HC1 removal device, a particulate removal device, a wet scrubber, a dry scrubber, and a combination thereof;

the halide or halogen is a liquid comprising HC1, HBr, HI, Br?, Cb, h, BrCl, IBr, IQ, C1F, PBr ₃ , PCk SCb, CuCh, CuBr _¾ Al ₂ Br ₆ , Feb, FeBr _y , FeCl _z , MnBr ₂ , MnCb, NiBr ₂ , NiCb, Nib, ZnBr , ZnCb, Znb, M hBr. NH C1, Ni l ,!, M b!·, FeNH ₄ Br ₄ , FeNH ₄ Ci ₄ , F ₂ , F , Cl Br , G, NH ₄ Br, NaBr, CaBr , NaCl, CaCl ₂ , M 1 i< Ί NH ₄ I, Nal, Cab, KI, KC1, HI, NH ₄ F, NaF, CaF , HF, LiBr, AgCl, AgBr, CHI3, CFBBr, AuBr, MgBr ₂ , MgCb, hydrates thereof, or combinations thereof wherein x, y, and z are independently 1, 2, 3, or 4, and

the one or more halide or halogen injection points are reversibly coupled to the liquid dispersion lance comprising:

a shell extending from first and second opposed ends;

a compressed air channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first halogen or halide channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end; and a second halogen or halide channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet [00173] Embodiment 62 provides a method of separating mercury from a mercury-containing gas using the system according to any one of Embodiments 1-61, the method comprising:

supplying coal from the coal-feed zone to the combustion zone; injecting the halide or halogen into the system through the one or more injection points;

contacting the halide or halogen with mercury in the mercury- containing gas to produce oxidized mercury; and

collecting the oxidized mercury in the scrubbing zone

[00174] Embodiment 63 provides the method of Embodiment 62, wherein the halide or halogen in injected into multiple injection points simultaneously [00175] Embodiment 64 provides the method of any one of Embodiments 62 or 63, comprising adjusting the diluent metering valve and the halogen or halide metering valve to deliver a diluted halogen or halide solution at a predetermined concentration to the one or more injection points.

[00176] Embodiment 65 provides the method of any one of Embodiments 62-64, further comprising pivoting the nozzle from a first angle to a second angle.

[00177] Embodiment 66 provides the method of any one of Embodiments 62-65, further comprising removably securing the injection system to the one or more injection points

[00178] Embodiment 67 provides the method of any one of Embodiments 62-66, wherein the coal is contacted with the halide or halogen during pulverization.

[00179] Embodiment 68 provides the method of any one of Embodiments 62-66, wherein an amount of the halide or halogen that is delivered to the one or more injection points is controlled manually or automatically.

[00180] Embodiment 69 provides the method of Embodiment 68, wherein the amount of the halide or halogen is adjusted in real time based on monitored parameter of the system. [00181] Embodiment 70 provides the method of Embodiment 69, wherein the monitored parameter is chosen from a temperature of the system, a flow of gas in the system, a load of the system, and a combination thereof.

[00182] Embodiment 71 provides a liquid dispersion lance for injecting an atomized liquid comprising a halide or halogen, the liquid dispersion lance comprising:

a shell extending from first and second opposed ends;

a halogen or halide channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first compressed air channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end, and

a second compressed air channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[00183] Embodiment 72 provides the liquid dispersion lance of

Embodiment 71, further comprising a nozzle attached to the second end and in flow communication with the outlet of the halogen or halide channel and the outlet of the second compressed air channel.

[00184] Embodiment 73 provides the liquid dispersion lance of

Embodiment 72, wherein the nozzle is configured to pivot in a range of from about 90 degrees to about 180 degrees relative to an axis extending from the first end to the second end.

[00185] Embodiment 74 provides the liquid dispersion lance of any one of Embodiments 72-73, wherein the perforations of the first compressed air channel are configured to deliver compressed air from the first compressed air channel to at least a portion of the perforations of the second compressed air channel and to an interstitial volume of the nozzle between the halogen or halide channel, first compressed air channel, second compressed air channel, and the shell.

[00186] Embodiment 75 provides a liquid dispersion lance for injecting an atomized liquid halide or halogen, the liquid dispersion lance comprising:

a shell extending from first and second opposed ends; a compressed air channel extending from an inlet proximate to the first end to an outlet proximate to the second end;

a first halogen or halide channel extending from an inlet proximate to the first end to a closed end proximate to the second end and having one or more perforations disposed between the inlet and the closed end; and

a second halogen or halide channel extending from a closed end proximate to the first end and an outlet located proximate to the second end and having one or more perforations disposed between the closed end and the outlet.

[00187] Embodiment 76 provides the liquid dispersion lance of

Embodiment 75, further comprising a nozzle attached to the second end and in flow communication with the outlet of the compressed air channel and the outlet of the second halogen or halide channel

[00188] Embodiment 77 provides the liquid dispersion lance of

Embodiment 76, wherein the nozzle is configured to pivot in a range of from about 90 degrees to about 180 degrees relative to an axis extending from the first end to the second end.

[00189] Embodiment 78 provides the liquid dispersion lance of any one of Embodiments 75-77, wherein the perforations of the first halogen or halide are configured to deliver the halogen or halide from the first halogen or halide channel to at least a portion of the perforations of the second halogen or halide channel and to an interstitial volume of the nozzle between the compressed air channel, first halogen or halide channel, second halogen or halide, and the shell.

[00190] Embodiment 79 provides the system of any one of clams 1-7578 wherein,

the coal-feed zone comprises a coal bunker, a coal feeder, and a coal pulverizer;

the scrubbing zone comprises a scrubbing device chosen from a NOx removal device, a SO ₂ removal device, a SO ₃ removal device, a Hg removal device, a HC1 removal device, a particulate removal device, a wet scrubber, a dry scrubber, and combinations thereof;

the halide or halogen is a solid comprising HCi, HBr, HI, Br ₂ , Cl ₂ , 1 ₂ , BrCl, IBr, IQ, C1F, PBn PC1 _5, SC1 ₂ , CuCh, CuBr ₂ , Al ₂ Br ₆ , l ei, FeBr _y , FeCi _z ,

MnBn, MnCb, NiBr ₂ , MCE, Nib, ZnBr ₂ , Z11CI2, Znk M l dir, M fiCi, M M. Ni i ;F. FeNH ₄ Br ₄ , FeNH ₄ Cl _4, F ₂ , F , Cl Br\ G, NH ₄ Br, NaBr, CaBr ₂ , NaCl, CaCh, MfrCl, M I d. Nal, Cal ··. KI, KCL HI, NH ₄ F, NaF, CaF ₂ , HF, LiBr, AgCl, AgBr, CHI ;, CH iBr, AuBr, MgBr ₂ , MgCb, hydrates thereof, or combinations thereof wherein x, y, and z are independently 1, 2, 3, or 4; and

the one or more halide or halogen injection points are reversibly coupled to the solid dispersion lance comprising:

a shell extending from first and second opposed ends; and a dispersion head at least partially disposed within the shell and adapted to dispense the solid halogen or halide through an injection point.

[00191] Embodiment 80 provides a solid dispersion lance for injecting a solid halide or halogen, the solid dispersion lance comprising:

a shell extending from first and second opposed ends; and

a dispersion head at least partially disposed within the shell and adapted to dispense the solid halogen or halide through an injection point.