| C L A I M S 1. A Modified Carbon Dioxide Capture and Storage System in Coal Fired Power Plants with formation of established fertilizers (System A.l), which is characterized in that it avoids the main barrier to the use of carbon dioxide capture technology, which is the cost of investment for the capture system and the cost of storage of the carbon dioxide, which is still an order of magnitude more expensive than the price level that would make competitive the use of the technology of carbon sequestration, which almost doubles the cost of electricity per kilowatt hour, Where the System A.l is also characterized by the fact that the use of ammonia as a carbon dioxide capture agent makes it possible to bind with the same production process, in the same phase and without further investments and the other pollutants contained in the flue gas of the Coal Fired Power Plants such as the sulfur and nitrogen oxides, the mercury and HCI, and the production of other chemical products other than Ammonium Bicarbonate, such as the Ammonium Sulfate and Ammonium Nitrate, which add value and which are used usually as fertilizers, Where the System A.l is also characterized by the fact that it modifies, simplifies and for the most part removes the components of the Conventional Carbon Dioxide Capture and Storage System with Ammonia in Coal Fired Power Plants, which even amends the final product, which instead of pure carbon dioxide, which is compressed and sent for permanent storage in underground geological formations, an expensive process with no commercial interest, where in the contrary the final product of carbon sequestration of the System A.l consists of established fertilizers with high added value, such as Ammonium Bicarbonate, Ammonium Sulfate and the Ammonium Nitrate, which are sold and leave a very significant net profit to the Power Plants, Where the System A.l is characterized by the following modifications, simplifications and deletions of components of the Conventional Carbon Dioxide Capture and Storage System with Ammonia in Coal Fired Power Plants (System A.0), when the invention is applied to Coal Fired Power Plants which have a Desulfurization System, whereby a drastic reduction in investment costs occurs, whereby the System A.l consists thereafter of the following parts, 1. The Subsystem (SI) of Supply, Cooling and Retention of Particulates of the Exhaust Gases (exists already in the System A.0), 2. The Subsystem (S2) of Supply of Clean Exhaust Gases to the Absorption Tower (exists already in the System A.0), 3. The Subsystem (S3) of the C02 Absorption Tower with Scrubbing with Ammonia Solution (exists already in the System A.0 with small modification), 4. The Subsystem (S4) for the Abduction of the Dense Solution of Products of the Absorption Tower (removed), 5. The Subsystem (S5A) for the Supply of the Ammonia Dilute Solution to the Absorption Tower (already exists in some Units, only a small modification is needed), 6. The Subsystem (S6) of the Regeneration Tower of the Ammonium Bicarbonate (ABC) (removed), 7. The Subsystem (S7) of the Abduction of the Waste of the Products of the Regeneration Tower (removed), 8. The Subsystem (S8) of Carbon Dioxide Compression for its Abduction and Storage (removed), 9. The Subsystem (S9) of Containment of the Residual Ammonia Vapors (incorporated in Subsystem (S10) with minimal modification), 10. The Subsystem (10) of Discharge to the Atmosphere of the Cold Exhaust Gases (exists already in the System A.0), Where the System A.l is also characterized by the fact that when the invention is applied to Coal Fired Power Plants which have a Desulfurization System, then the total investment for the capture of the emitted carbon dioxide and other pollutants with parallel production of useful products with high added value, it is simplifies and becomes extremely attractive for business, even if the profit from avoiding the carbon dioxide tax is not taken into account, Where the System A.l is characterized by the fact that it consists in the modified application of the conventional process for the capture and storage of the carbon dioxide and the other pollutants (S02, S03, NOx, Hg, HCI) with ammonia in coal-fired power plants, where instead of production of pure carbon dioxide for permanent storage, is applied the following modification of the production process and of the system, for the production of fertilizers, Where the System A.l is characterized in that the process of carbon dioxide capture in Ammonium Bicarbonate (2NH4HC03) and of the two other pollutants, namely sulfur oxides and nitrogen oxides (S02, S03, NOx,) in Ammonium Sulfate [2 (NH4) S04] and Ammonium Nitrate (NH4N03), respectively, by scrubbing with the ammonia solution takes place in the Absorption Tower (S3) where the above products are gathered in the dense solution at the bottom of the Absorption Tower (S3), from which they are further obtained as fertilizers, based on the known and established separation technology for each fertilizer, and there is no reason to forward it to the Desorption Tower (S6) for the regeneration of Ammonium Bicarbonate and the disposal of the rest waste, Where consequently results a modification of the production process and the C02 capture system, which has as consequence the removal of the Subsystem (S4) of Abduction of the Concentrated Solution Product of the Absorption Tower (S3), the removal of the ABC Regeneration Subsystem (S6) in the Desorption Tower (S6), as well as of the Subsystem of the Abduction of the Waste (S7) as well as of the C02 Compression Subsystem (S8), which are now not required and their removal reduces drastically both the investment costs and the operation and maintenance costs, It is also characterized in that in the place of the abolished Subsystems (S4), (S6), (S7) and (S8), is implemented the Modified Subsystem (S5A) for the Supply of the Ammonia Dilute Solution to the Absorption Tower (S3), by creating near the Cooling Tower of the Coal Fired Power Plant of a Scrubbing Tower (S5A), also built on the basis of the corresponding established technology, in which the exhaust gas stream, which exits from the Absorption Tower (S3), is scrubbed with water, thus on the one hand are bound the escapes of C02 and Ammonia from the Absorption Tower (S3) and on the hand is created the poor solution of carbonated ammonia, which is necessary for the feeding with Ammonia of the Absorber Tower (S3), It is also characterized by the fact that in order to assist in raising to the atmosphere and discharging of the cold exhaust gases after leaving the Subsystem (S9), which follows the (S5A), is abolished the conventional Flue Gas Chimney (10) with Reheat of the Unit Exhaust Gases, where the exhaust gases outlet after the Subsystem (S9) is carried out in the Cooling Tower of the Unit, where the upward exhaust discharge stream is created by mixing with the rising hot water vapor stream of the Cooling Tower, which contributes to the final washing of the ammonia vapor residues (traces of 350 ppmv) and C02, which have escaped from the Subsystem (S5A), which are collected as a dilute carbonated solution on the floor of the Cooling Tower and recycled, while the ultimately discharged clean exhaust gases now contain small traces of ammonia vapor well below the permissible limits for environmental reasons, whereby the above leaching of the ammonia vapor traces in the Cooling Tower allows the removal of the final Subsystem (S9) Containment of the Residual Ammonia Vapors, which would otherwise be necessary for environmental reasons, Where the System A.l is also characterized by the fact that it avoids not only the investment costs and operating costs of the avoided Subsystems (S4), (S6), (S7), (S8) and (S9), but also the transport and permanent storage cost of the pure carbon dioxide and other pollutants produced as well as, which is often comparable to the cost of the initial C02 separation and capture investment, Where the System A.l is also characterized in that when applied when to Coal Fired Power Plants which have a Desulfurization System, while the Subsystems (SI) of Supply, Cooling and Retention of Particulates of the Exhaust Gases and Subsystem (S2) of Supply of Clean Exhaust Gases to the Absorption Tower, exist and remain the same, while the Tower of Capture of Sulfur Oxides by scrubbing with a solution of Calcium Hydroxide (Ca(OH)2), which is now inactive, can be converted with minimal interference (small adaptation of the internal Contact Packages) in order to be used as an Absorption Tower (S3) for the production of Ammonium Bicarbonate and the others particularly useful and with high added value as fertilizers, namely of the Ammonium Sulfate and the Ammonium Nitrate, just as in the established process mentioned above, Moreover, the System A.l is characterized by the fact that when it is applied to Coal Fired Power Plants with a Desulfurization System, the total investment for the capture of the emitted carbon dioxide and other pollutants while producing useful products with high added value is limited to (S5A), which in some Desulfurization systems already exists in a slightly different form, as a second embodiment of the modified Subsystem (S5A) Calcium Hydroxide Decomposition Tower for more complete Desulfurization and which, with very little adaptation, can function as a scrubbing tower with water of the exhaust gas from the S3, which still contains a small amount of carbon dioxide as well as ammonia vapor escapes, which by scrubbing with water in the (S5A) create the dilute carbonated ammonia solution, which is recycled to the Absorption Tower (S3) where it is necessary for the absorption process of the carbon dioxide, In addition, the System A.l is characterized by the fact that when it is applied to Coal Fired Power Plants with a Desulfurization System, then they make use of the Subsystem (10) itself as is, which is consisted in the supply of the cold exhaust gas after Desulfurization inside the Cooling Tower of the Unit, where the upward exhaust discharge stream is created by mixing with the rising hot water vapor stream of the Cooling Tower, while also being used as a final retention Subsystem (S9) for the small final ammonia vapor escapes as above, Where the System A.l is further characterized by the fact that the Electricity Production Unit is now operating as a RES Power Unit capable of covering the night load curve, which is extremely important for covering the incapability of RES to operate during the night (PV) or when the wind does not blow (Aeolian), which is the Achilles' heel of these two RES. 2. A System A.2 of Carbon Dioxide Capture with Ammonia in Coal Fired Power Plants without a Desulfurization System and with fertilizer production, such as in the System A.l in Claim 1, but characterized by the need to implement the Subsystems (SI) , (S2), (S3), (S5A), (S9) and (10) and by that it doesn't need and abolishes the Subsystems (S4), (S6), (S7) and (58), 3. A System A.3 of Capturing of Carbon Dioxide with Ammonia in Cement Industry Units and with the production of fertilizers, such as the Systems A.l in Claim 1 and A.2 in Claim 2, which is also characterized by the need to implement the Subsystems (SI) , (S2), (S3), (S5A), (59) and (10) and in that it does not need and abolishes the Subsystems (S4), (S6), (S7) and (S8), 4. A System A.4 of Capturing of Carbon Dioxide with Ammonia in Refineries and with the production of fertilizers, such as the Systems A.l in Claim 1, A.2 in Claim 2 and A.3 in Claim 3, which is also characterized by the need to implement the Subsystems (SI), (S2), (S3), (S5A), (S9) and (10) and in that it does not need and abolishes the Subsystems (S4), (S6), (S7) and (S8), 5. A System A.5 of Capturing of Carbon Dioxide with Ammonia in various Industries, Buildings or Installations with C02 emissions and production of fertilizers, such as Systems A.l in Claim 1, A.2 in Claim 2, A.3 in Claims 3 and A.4 in Claim 4, which is also characterized by the need to implement the Subsystems (SI), (S2), (S3), (S5A), (S9) and (10) and in that it does not need and removes the Subsystems (S4), (S6), (S7) and (S8), 6. A System A.6 of Capturing of Carbon Dioxide with Ammonia, as well as of Sulfur Oxides and other pollutants and with fertilizer production, such as Systems A.l in Claim 1, A.2 in Claim 2, A.3 in Claim 3, A.4 in Claim 4 and A.5 in Claim 5, in Diesel Engines with Combustion of Heavy Oil or Crude with High Sulfur and other pollutants in sea-going shipping or in electricity generation, which is also characterized by the need to implement the Subsystems (SI), (S2), (S3), (S5A), (S9) and (10) and in that it does not need and removes the Subsystems (S4), (S6), (S7) and (S8), 7. A System A.7 of Capturing of Carbon Dioxide with Ammonia, as well as of Sulfur Oxides and other pollutants and with fertilizer production, such as the Systems A.l in Claim 1, A.2 in Claim 2, A.3 in Claim 3, A.4 in Claim 4, A.5 in Claim 5 and A.6 in Claim 6, in Steam Boilers fired with Heavy Oil or Crude with High Sulfur and other pollutants in the production of electrical energy, which is also characterized by the need to implement the Subsystems (SI), (S2), (S3), (S5A), (S9) and (10) ) and in that it does not need and removes the Subsystems (S4), (S6), (S7) and (S8), 8. A Subsystem (S3) of a C02 Absorber Tower with Scrubbing of an Ammonia Solution with a minor modification in the Calcium Hydroxide Scrubbing Subsystem of the Desulfurization System, in Coal Fired Power Plants or other Units with a Desulfurization System, 9. A Subsystem (S9) of Retention of Ammonia Vapors Leakages, which is integrated into the existing Subsystem (10) of Discharge in the Atmosphere of the Cold Exhaust Gases of the Desulfurization System of Coal Fired Power Plants or other Desulfurized Units, 10. A Subsystem (10) of Discharge in the Atmosphere of the Cold Exhaust Gases, which operates also as a Subsystem (S9) of Retaining Ammonia Vapor Leakages of Coal Fired Power Plants or other Desulfurized Units. |
A.l. GENERALLY
The capture of carbon dioxide emissions in coal-fired power plants is now an imperative for the survival of these Units, which should otherwise be shut down and replaced by RES Units in accordance with the UN's COP21 decision in Paris in December 2015. However, because coal-fired power is very important in most countries, where coal (coal or lignite) is domestic and substitutes for expensive fossil fuel imports, an effort is made to capture the carbon dioxide emissions so that electricity production does not burden the environment. Until today, despite the funding and demonstration projects that have been carried out, this effort has not been able to develop carbon dioxide capture technologies that are economically and environmentally sustainable to produce clean coal production and are still in the process of research and development.
It is therefore necessary to reduce both the cost of the carbon dioxide capture (Capex) investment and the specific cost of the cost of the kilowatt-hour produced so that its application becomes competitive and sustainable.
A.2. THE KNOWLEDGE FIELD TODAY
Carbon dioxide capture technology has made considerable progress in other applications such as ammonia and fertilizer production, as well as applications where the carbon dioxide produced is sold as a commercial product for various industrial uses. However, for the implementation of the Carbon Dioxide Units, there is a need to reduce both the cost of the investment in Capex and the cost of the produced kilowatt hour so that its application becomes competitive and sustainable, as well as for the possibility of alternative storage of carbon dioxide when not used as a commercial product. The main barrier to the use of carbon capture technology is investment costs and storage costs, which are still an order of magnitude more expensive than the price level that would compete with the use of carbon capture technology. The European Union is predicted to raise the carbon tax from the current low of 6-8€ / Ton.C0 2 to 20-25€ / Ton.C02, while in some countries this is already the case (for example in England is valid already a carbon dioxide tax of £ 18 = ($ 25,€ 22) / Ton.C0 2 ), the imposition of which will enhance the viability of carbon capture and storage systems. Carbon dioxide capture with ammonia is now considered to be both superior in terms of both cost and carbon efficiency and carbon dioxide yield with monoethanolamines (MEA), and there is focused the research on capture of coal dioxide.
B. ADVANTAGES OF THE PRESENT INVENTION
The main advantages of the present invention of carbon dioxide binding in the form of fertilizers are as follows:
- Carbon dioxide capture technology in the form of ammonia fertilizer is known and is being implemented and used for over 40 years in countries like China, where both ammonia and carbon dioxide are produced simultaneously to produce ammonium bicarbonate, a very successful fertilizer, - In addition, the use of ammonia as a carbon dioxide capture agent makes it possible to bind, in the same production process, in the same phase and without further investments, also of the other pollutants contained in the exhaust gases of the coal-fired power plants, such as sulfur oxides, nitrogen oxides, mercury and HCI and production of other value adding chemicals such as Ammonium Sulfate and Ammonium Nitrate, which are commonly used as fertilizers.
C. DRAWINGS
- Drawing 1 shows the General Layout of Capture of Carbon Dioxide System with Ammonia in Coal Fired Power-Plants without the production of fertilizers [Fig. 1. Schematic of the ammonia-based C0 2 capture process (Zhuang et al., 2011).
- Drawing 2 shows the General Layout of Capture of Carbon Dioxide System with Ammonia in Coal Fired Power-Plants without Desulfurization System and with Production of Fertilizers.
- Drawing 3 shows the General Layout of Capture of Carbon Dioxide System with Ammonia in Coal Fired Power-Plants with an Existing Desulfurization System and Production of Fertilizers
D. DESCRIPTION OF THE CAPTURE OF CARBON DIOXIDE IN FORM OF FERTILIZERS IN COAL-
FIRED POWER PLANTS
The Conventional System A.O of Carbon Dioxide Capture and Storage with Ammonia in Coal Fired Power-Plants is characterized in that it consists of the following parts as a whole or a combination of some of them (Drawing 1):
1. The Subsystem (SI) of Supply, Cooling and Retention of Particulates of the Exhaust Gases,
2. The Subsystem (S2) of Supply of Clean Exhaust Gases to the Absorption Tower,
3. The Subsystem (S3) of the C0 2 Absorption Tower with Scrubbing with Ammonia Solution,
4. The Subsystem (S4) for the Abduction of the Dense Solution of Products of the Absorption Tower,
5. The Subsystem (S5) for the Supply of the Ammonia Dilute Solution to the Absorption Tower,
6. The Subsystem (S6) of the Regeneration Tower of the Ammonium Bicarbonate (ABC),
7. The Subsystem (S7) of the Abduction of the Waste of the Products of the Regeneration Tower,
8. The Subsystem (S8) of Carbon Dioxide Compression for its Abduction and Storage, 9. The Subsystem (S9) of Containment of the Residual Ammonia Vapors (follows (S3))
10. The Subsystem (10) of Abduction to the Atmosphere of the Exhaust Gas with Exhaust Gas Reheating Chimney,
Where the Subsystems (SI), (S2) and (10) are characterized by the fact that they are constructed on the basis of the known since 40 years production of Ammonium Bicarbonate by carbon dioxide capture with parallel production of ammonia from coal in China and elsewhere (Zhuang et al., 2011),
Where the Subsystem (S3) is also built on the basis of the known since 40 years technology of production of Ammonium Bicarbonate by capture of carbon dioxide with parallel production of ammonia from coal in China and elsewhere (Zhuang et al., 2011),
Where the Subsystems (S4), (S5), (S6), (S7), (S8), (S9) and Subsystems (S4) and S5 are characterized in that they are constructed on the basis of known technology of capture of carbon dioxide using ammonia for the production and compression of pure C0 2 for transport and permanent storage in underground geological formations (Zhuang et al., 2011),
Where the Subsystems (SI) through (10) above are further characterized in that they cooperate as follows in the description of the ammonia-based C02 capture technology below, wherein a schematic illustration of the process is shown in Drawing 1, wherein the C0 2 capture by an absorbent liquid (ammonia solution) is effected by an exhaust gas stream rich in C0 2 , which through the Subsystems (SI) and (S2) is fed to an Absorber Tower (S3) (Absorber or Absorber Column) and then via the Subsystem (S4) to a Tower of Desorption (S6) (Desorber, Regenerator or Stripper).
For the ammonia-based C0 2 capture process, is used as an absorber liquid a partially carbonated aqueous solution of ammonia (a composition close to that of NH 4 HC0 3 Ammonium Carbonate or AC) which is fed to the Absorption Tower (S3) through the Subsystem (S5) of Diluted Ammonia Solution. Pure aqueous ammonia solution cannot be used because of the extremely high vapor pressure of ammonia (Zhuang et al., 2011),
As shown in the process (Drawing 1), the first step is the absorption of C02, in which the exhaust gas (the C0 2 containing gas) enters the Absorption Tower (S3) through the bottom and the absorption fluid stream enters through the top. This process is known as countercurrent flow. In this configuration, a certain amount of C0 2 (the target is C0 2 capture by 90%) is removed from the gas coming out of the top of the Absorption Tower (S3), while the absorption fluid stream collected at the bottom of the Absorption Tower (S3) is very rich in C0 2 ,
Where the composition of the absorbent liquid in the bottom of the Absorption Tower (S3) is mainly Ammonium Bicarbonate (2NH 4 HC0 3 or ABC). Subsequently the Concentrated Solution Product of the Absorption Tower (S3) is propelled for regeneration of the ABC to the Subsystem (S6) of the Carbon Dioxide Regeneration Tower through the Subsystem (S4) of Abduction of the Concentrated Solution Product of the Absorption Tower (S3), where the regeneration of ABC is an endothermic process, and a reheater at the bottom of the Regeneration Tower (S6), evaporates some of the liquid, decomposes the ABC, releasing the C0 2 (Zhuang et al., 2011, Darde et al., 2008),
The vapors (C0 2 and water vapors) then flow upward through the Regeneration Tower (S6), and come into contact with the down flowing absorbing liquid and release more C0 2 . The regeneration can operate at atmospheric pressure, 60-70°C, or at higher pressure, e.g. 20 atm, 120°C (Zhuang et al., 2011, Black et al., 2008). The liquid collected at the bottom of the Regeneration Tower (S6) is now C0 2 -poor with a composition close to that of Ammonium Carbonate (NH 4 HC0 3 or AC) and is cooled before being recycled to the Absorption Tower (S3) with heat exchange with the C0 2 -rich current in the HX Heat Exchanger between the Subsystems (S4) and (S5),
An important element in the construction of both the Absorption Tower (S3) and Desorption Tower (S6) are their Contact Packing Packages. The Contact Packing provides the necessary contact surface in the region within the Towers (S3) and (S6), thereby allowing increased fluid-gas contact which results in enhanced mass and heat transfer between the various process phases. The mass and heat transfer efficiency is an important factor in determining the C0 2 absorption efficiency and hence the size of the equipment.
Then the cold exhaust gas after the first scrubbing with water at the top of the Absorption Tower (S3), where most of the ammonia vapors that have escaped the C0 2 absorption process are removed [Subsystem (S9) of Ammonia Vapor Depletion] and then driven in the Subsystem (10) of Exhaust to the Atmosphere of the Cold Exhaust Gases with Exhaust Gas Reheat Chimney, after (S9),
Where the principle of chemistry is based on the C0 2 -NH 3 -H 2 0 system and the main reactions involved in the above process are summarized below (Zhuang et al., 2011):
Where the effective species in the absorbent liquid are ionic. The most abundant species are: NH 4 + , HC0 3 kai C0 3 2+ . Molecular forms of NH 3 and C0 2 in the absorbent liquid are present at very low concentrations. It is still convenient to describe the system using an equivalent concentration of NH 3 (we assume that all the nitrogen compounds (N) contained are in the form of NH 3 ). Some amounts of C0 2 and vapors NH 3 escape over the liquid.
In the C0 2 -NH 3 -H 2 0 system, depending on temperatures and concentrations, ABC and AC can precipitate as solids and be separated from the solution of ammonia, water, ABC and AC using centrifugal devices and then they are forwarded to the Subsystem (S6) of the ABC Regeneration Tower with the collaboration of the (S7) Subsystem for the Abduction of the Waste Products of the Regeneration Tower and the associated Subsystem (SS) of Carbon Dioxide Compression for Abduction and Storage,
Where the present invention is characterized in that it comprises the modified application of the above process for the capture and storage of carbon dioxide and other pollutants (S0 2 , S0 3 , NO x , Hg, HCI) with ammonia in coal-fired power plants where instead of producing pure carbon dioxide for permanent storage (eg in underground geological formations), which is expensive and is currently in the phase of research, the following modification of the production process and the system is proposed for the production of fertilizers,
Where the carbon dioxide capture process in Ammonium Bicarbonate (2NH4HC03) and the two other pollutants, namely sulfur oxides and nitrogen oxides (S0 2 , S0 3 , NO x ,), in Ammonium Sulfate, 2(NH 4 )S0 4 and Ammonium Nitrate, NH 4 N0 3 respectively, by spraying with the ammonia solution, takes place again in the Absorption Tower (S3), where the above products are gathered in the dense solution at the bottom of the Absorption Tower (S3), from which they are now taken as fertilizers, based on known and established separation technology procedure for each fertilizer and need not be forwarded in the Desorption Tower (S6) for regeneration of the Ammonium Bicarbonate and discarding the rest as waste.
Consequently results a modification of the production process and the C0 2 capture system, which has as consequence the abolition of the Subsystem (S4) of Abduction of the Concentrated Solution Product of the Absorption Tower (S3), the removal of the ABC Regeneration Subsystem (S6) in the Desorption Tower (S6), as well as of the Subsystem (S7) of Rejection of the Waste as well as of the C0 2 Compression Subsystem in the System (S8), which are now not required and their removal drastically reduces both investment costs and operating and maintenance costs,
It is also characterized in that in the place of the abolished Subsystems (S4), (S6), (S7) and (S8), is implemented the modified System (S5A) of Supplying of the Dilute Solution of Ammonia to the Absorption Tower (S3), by creating near the Cooling Tower of the Coal Fired Power Plant of a Scrubbing Tower (S5A) also constructed according to the corresponding conventional technology, in which the exhaust gases stream exiting the Absorption Tower (S3) is sprinkled with water, and thus, on the one hand, binding the leakages of the C0 2 and of the Ammonia from the Absorption Tower (S3) and on the other hand is created the poor solution of carbonated ammonia, which is necessary for the supply with Ammonia of the Absorption Tower (S3),
It is also characterized by the fact that in order to support the elevation to the atmosphere and the discharge of the cold now exhaust gases after their exit from the Subsystem (S9), which follows the (S5A), is abolished the conventional Chimney (10) with Reheat of the Exhaust Gases of the Unit and the exit of the exhaust Gases after the Subsystem (S9) is effected inside the Cooling Tower of the Unit, where the upward exhaust gases discharge stream is generated by mixing with the rising hot water vapor stream of the Cooling Tower (Megalopolis Unit IV), which contribute to the final depletion of the residual ammonia vapors (traces of the order of 350 ppmv) and of the C02, which have escaped from the Subsystem (S5A), which are collected as a dilute carbonated solution on the floor of the Cooling Tower and are recycled, while the finally discharged clean exhaust gas contains now minimal traces of ammonia vapors much below of the permitted limits for environmental reasons, where the above mentioned depletion of the residual ammonia vapors in the Cooling Tower permits the removal also of the final Subsystem (S9) of Ammonia Vapor Depletion, which would be otherwise necessary for environmental reasons,
It is also characterized by the fact that the present invention, avoids not only the cost of the investment and the cost of the operation of the abolished Subsystems (S4), (S6), (S7), (S8) kai (S9), but also the cost of transportation and permanent storage of the produced pure carbon dioxide and the other pollutants, which in many cases is comparable with the cost of the initial investment of separation and capture of the C02,
It is also characterized by the fact that instead of the production of pure carbon dioxide and the other pollutants without commercial value, which are destined for permanent storage, it produces standard fertilizers with high added value, the sale of which results in a significant net profit for the Power Plant,
It is also characterized by the fact that in this case the Subsystems (SI) of Supplying, Cooling and Retention of Particulates of the Exhaust Gases and the Subsystem (S2) for the Supply of Clean Exhaust Gases to the Absorption Tower, exist and remain the same, while the Tower of the Sulfur Oxide Capture by scrubbing with a Solution of Calcium Hydroxide (Ca(OH) 2 ), which now remains inactive, can be converted with minimal interference (small adjustment of the internal Contact Packages) to be used as an Absorption Tower (S3) of Carbon Dioxide for the production of Ammonium Bicarbonate and of the other particularly useful and with high added value as fertilizers, i.e. of the Ammonium Sulfate and Ammonium Nitrate, just as in the standard procedure mentioned above,
It is also characterized by the fact that because the purpose is no longer the capture and storage of pure carbon dioxide but the production of Ammonium Bicarbonate produced in the Carbon Dioxide Absorber Tower (S3) (together with the products from the capture of the remaining pollutants S0 2 , S0 3 , NO x , Hg, HCI and in particular of the useful and with high added value as fertilizers, namely of the Ammonium Sulfate and Ammonium Nitrate), thereby removing the Subsystem (S4) for the Abduction of the Dense Solution of Products of the Absorption Tower, the Subsystem (S6) of the Regeneration Tower of the ABC, the Subsystem (S7) of the Abduction of the Waste of the Products of the Regeneration Tower (S6) and the Subsystem (S8) of Carbon Dioxide Compression for its Abduction and Storage,
Moreover, the present invention is characterized in that when applied to Coal Fired Power Plants which have already a Desulfurization System, the total investment for the capture of the emitted carbon dioxide and of the other pollutants, while producing useful products with high added value, is limited to the realization only of the modified Subsystem (S5A) of Supply of Diluted Ammonia Solution to the Absorption Tower (S3), which in some Desulfurization systems already exists in a slightly different form, as a second Calcium Hydroxide Scrubbing Tower for a more complete Desulfurization and which, with a very small adjustment, can function as a Water Scrubbing Tower of the exhaust gas from the Absorption Tower (S3), which still contains a small percentage of carbon dioxide as well as escapes of ammonia vapors, which by water scrubbing in the (S5A) generates the dilute carbonated ammonia solution, which is recycled to the Absorption Tower (S3), where it is necessary for the absorption process of the carbon dioxide,
In addition, the present invention is characterized in that when applied to Coal Fired Power Plants which have already a Desulfurization System, they use also the Subsystem (10) itself as is, which consists in supplying the cold exhaust gases after Desulfurization to the inside of the Cooling Tower of the Unit, where the upward exhaust gases discharge stream is generated by mixing with the rising hot water vapor stream of the Cooling Tower, while also being used as a Subsystem (S9) for the retention of the small final escapes of ammonia vapors as above,
It is also characterized by the fact that when the invention is applied to Coal Fired Power Plants which have already a Desulfurization System, the total investment for the capture of the emitted carbon dioxide and of the other pollutants, while producing useful products with high added value, is simplified as shown in Drawing 3 and consists thereafter of the following parts, in their entirety or a combination of some of them, namely,
1. The Subsystem (SI) of Supply, Cooling and Retention of Particulates of the Exhaust Gases (exists already in the System A.0),
2. The Subsystem (S2) of Supply of Clean Exhaust Gases to the Absorption Tower (exists already in the System A.0),
3. The Subsystem (S3) of the C0 2 Absorption Tower with Scrubbing with Ammonia Solution (exists already in the System A.0 with small modification),
4. The Subsystem (S4) for the Abduction of the Dense Solution of Products of the Absorption Tower (removed),
5. The Subsystem (S5A) for the Supply of the Ammonia Dilute Solution to the Absorption Tower (already exists in some Units, only a small modification is needed),
6. The Subsystem (S6) of the Regeneration Tower of the Ammonium Bicarbonate (ABC) (removed),
7. The Subsystem (S7) of the Abduction of the Waste of the Products of the Regeneration Tower (removed),
8. The Subsystem (S8) of Carbon Dioxide Compression for its Abduction and Storage (removed),
9. The Subsystem (S9) of Containment of the Residual Ammonia Vapors (incorporated in Subsystem (10) with minimal modification),
10. The Subsystem (10) of Discharge to the Atmosphere of the Cold Exhaust Gases (exists already in the System A.0),
Finally, it is characterized by the fact that when the invention is applied as above to Coal Fired Power Plants which have already a Desulfurization System, the total investment for the capture of the emitted carbon dioxide and other pollutants while producing useful products with high added value is simplified as shown above and in Drawing 3 and becomes extremely attractive for business, even if the profit from avoiding the carbon dioxide tax is not taken into account,
It is further characterized by the fact that the Power Generation Unit now functions as a RES Unit with capability to cover the night load curve, which is extremely important to cover the incapacity of operation of the the RES Units also during the night (PV) or when the wind does not blow (Aeolian), which is the Achilles' heel of these two RES.
REFERENCES
[1]) Zhuang et al., 2011"From ammonium bicarbonate fertilizer production process to power plant C02 capture"
[2] Darde et al., 2008
[3] TBL_FOREIGN_HO_20120723PM51201.6.25.6(jeongbowan)
[4] Hai Yu CSIRO Energy Technology "Development of an Aqueous Ammonia Based PCC Technology for Australian Conditions"
[5] Blacket al., 2008