MACEDA, Joseph, P. (939 Union Street, Unit 1aBrooklyn, NY, 11215, US)
VANDERBORG, Nicholas, E. (495 Locaust Place, Boulder, CO, 80304, US)
GRIMES, John, L. (602 Roosevelt Street, Westfield, NJ, 07090, US)
SINGAPORE TECHNOLOGIES DYNAMICS PTE LTD (249 Jalan Boon Lay, Singapore 3, 61952, SG)
AIKEN, Blair, M. (92 Main Street Apt. 3b, Cooperstown, NY, 13326, US)
MACEDA, Joseph, P. (939 Union Street, Unit 1aBrooklyn, NY, 11215, US)
VANDERBORG, Nicholas, E. (495 Locaust Place, Boulder, CO, 80304, US)
GRIMES, John, L. (602 Roosevelt Street, Westfield, NJ, 07090, US)
CLAIMS
What is claimed is:
1. A process for fuel feedstock production, comprising the steps of: providing a biocolumn having a base and a top; introducing a consortium of microorganisms into said biocolumn; delivering a nutrient, a renewable energy source and a carbon source into said biocolumn; reacting said consortium with said nutrient, said renewable energy source and said carbon source at controlled conditions; generating a fuel feedstock product of said reaction; removing said fuel feedstock from said biocolumn; and maintaining growth and propagation of said consortium allowing continuous operation of said biocolumn.
2. The process of claim 1, wherein said steps of fuel production are operating within five zones situated in the following order from said top of said biocolumn: an aerobic zone, a microaerophilic zone, an oxidizing zone, a redox zone and a reducing zone.
3. The process of claim 1 further comprising the step of introducing photon energy through said top, permeable to said photons into said biocolumn.
4. The process of claim 3, wherein said photon energy is selected from the group consisting of an external fiber optic source, a natural light, an internal source generated by electrical light and combinations thereof. 5. The process of claim 1, wherein said renewable energy source is a geothermal energy, a solar thermal energy, a photovoltaic energy, an external waste heat, a heat of internal reactions or combinations thereof.
6. The process of claim 1, wherein said nutrient is selected from the group consisting of a geothermal fluid, an organic waste slurry biomass, a coal, a hydrocarbon and combinations thereof.
7. The process of claim 1, wherein said nutrient is water containing.
8. The process of claim 1, wherein said carbon source is selected from the group consisting of atmospheric air, a carbon dioxide source, an organic waste, a coal, a hydrocarbons, a geothermal fluid, an internal product of said consortium growth, propagation and reaction, and combinations thereof. 9. The process of claim 1, further comprising the step of delivering each of said carbon, said nutrient and said energy to said biocolumn through single or multiple inputs at designated depths to said biocolumn.
10. The process of claim 1, further comprising the step of removing said feedstock products through single or multiple outputs at designated depths from said biocolumn.
11. The process of claim 1, further comprising the step of creating a temperature gradient along said biocolumn with a temperature reduced as moving upward said biocolumn by using internal thermal baffles with heat exchangers between zones .
12. The process of claim 1 further comprising the step of sustaining said base at a temperature between about 60 0 C and about 120 0 C. 13. The process of claim 2, wherein a temperature of said aerobic zone is about 40 0 C.
14. The process of claim 1, wherein said consortium of microorganisms is selected from the group consisting of phototrophs, chemotrophs, autotrophs, heterotrophs, and combinations thereof. 15. A process for fuel feedstock production, said process comprising the steps of: providing a biocolumn having a base and a top; introducing a consortium of microorganisms into said biocolumn; delivering a nutrient, a renewable energy source and a carbon source to said biocolumn; introducing photon energy through said top, permeable to said photons; operating said base at a temperature of between about 60°C and about 120°C. sustaining a temperature gradient and a pH gradient along said biocolumn; reacting said consortium with said nutrient, said renewable energy sources and said carbon source at controlled conditions; generating fuel feedstock products of said reaction in said biocolumn; removing said products from said biocolumn; and maintaining growth and propagation of said consortium allowing continuous operation of said biocolumn.
16. The process of claim 15, wherein said steps of fuel production are operating within five zones of said biocolumn, situated in the following order from said top: an aerobic zone, a microaerophilic zone, an oxidizing zone, a redox zone and a reducing zone.
17. The process of claim 16, wherein said temperature gradient decreases through said zones to a temperature of about 4O 0 C in said aerobic zone.
18. A process for fuel feedstock production, said process comprising the steps of: reacting a consortium of microorganisms with a nutrient, a renewable energy source and a carbon source at controlled conditions; generating a fuel feedstock product of said reaction; removing said fuel feedstock; and maintaining growth and propagation of said consortium allowing continuous operation of said process.
19. A process of claim 18, wherein said steps are operating within five zones: an aerobic zone, a microaerophilic zone, an oxidizing zone, a redox zone and a reducing zone.
20. A process of claim 19, wherein said steps are operating within said zones distributed in separate single-zone tanks interconnected to function as a complete biocolumn. |
CONSORTIAL GROWTH OF MICROORGANISMS FOR FUEL FEEDSTOCKS
FIELD OF INVENTION
The invention relates to the methods and systems for producing fuel feedstocks such as biogases, bioliquids and biosolids from microorganisms in a controlled manner with continuous inputs from dispersed energy sources, various carbon sources and nutrient feeds.
BACKGROUND OF THE INVENTION
Currently, the petrochemical industry primarily relies on finding existing deposits of stored hydrocarbons for subsequent refinement into fuels or chemical feedstocks for chemical synthesizing or processing. Next, the fossil carbon atoms contained in the fuel are combusted or thermally processed which releases gaseous carbon dioxide into the atmosphere as an emission. There are natural processes that reclaim carbon dioxide (CO 2 ) from the atmosphere. Those processes are photosynthesis, weathering of rock and capture by marine organisms. However, the rate of the natural processes to remove CO2 from the atmosphere cannot keep up with the current rate of industrial CO 2 emissions. It would be advantageous to develop methods and systems by which the carbon dioxide emissions directly or those already in the atmosphere are used as a feedstock input to produce biogases, bioliquids and biosolids. The present invention addresses this need.
The value of renewable energies, like geothermal, solar, hydroelectric and wind are limited by the high cost to store and move that energy to population centers.
Geothermal energy provides for regional electrical and heating needs, but no practical means exist to capture and
export that energy. The energy available from renewable sources, like solar, hydroelectric and wind is limited by distance to population centers, weather, cost of energy- storage and inefficient and expensive electrical distribution networks. The conversion of other alternative energy from other renewable organic feedstocks, like manure or wood chips, has been under utilized, as well. It would be advantageous to develop methods and systems that can maximize the value of these renewable energy sources and allow the energy export by converting that energy directly into biogases, bioliquids and biosolids, that will be processed into fungible fuels. The present invention addresses this need.
Nature has either scattered or isolated natural occurring microorganism colonies and their growth is limited by the availability of carbon, nutrients and energy. For, example geothermal vents are abundant source of energy and nutrients to promote growth of some thermophilic prokaryotes (bacteria and archaea) . These prokaryotes are specially adapted to grow in these environments. However, their growth could be enhanced if there were other colonies of microorganisms present with which to exchange reaction products, by-products and energy. Environmental Microbiology vol. 2(1), 11 - 26 (2000) reports that in nature several species or populations of microorganisms can function in a co- coordinated fashion so that production, growth and nutrient cycling are enhanced over what a single species or population can achieve alone under similar environmental conditions. Functionally, the consortium exceeds the sum of the parts. In consortial relationships, energetically and nutritionally beneficial metabolites and nutrients are
exchanged among participants, leading to optimal production and nutrient cycling in the community as a whole. It would be advantageous to develop methods and systems that can collect dispersed microorganism colonies into a single bioreactor or a series of bioreactors to maximize their growth by providing a continuous supply of carbon, nutrients and energy while continuously removing the byproducts produced in forms of biogases, bioliquids and biosolids. The present invention addresses this need. Nature has provided many organisms that use photosynthesis for growth. The function of these organisms has been to capture atmospheric carbon. However, the atmosphere, plants and soil detritus represent only a few percent of the world's carbon inventory. The vast majority is stored in the ocean, either in solution, as carbonates or as methane hydrates. Recent discoveries, at deep-ocean thermal vents and in layers well below light penetration, have shown that bacterial species are carrying out photosynthetic-like processes under a wide range of conditions. These organisms live in symbiotic balance from the seafloor to the surface. It is important to remember that these phototropes are the most recently evolved organisms. The vast majority of living species evolved without photosynthesis. Their populations are dependent on temperature, pH, nutrient availability and ocean currents. It would be advantageous to develop methods and systems that can maximize the use of photosynthesis and other mechanisms to capture carbon from carbon dioxide by helping the growth of microorganism colonies that produce biogases, bioliquids and biosolids. ASAE/CSAE Meeting Presentation,
Paper number: MB04-111 (2004) reports that the relationship of algae microorganism growth rate from light intensity is
temperature dependent. Generally, as the temperature increases, the saturation intensity increases which results in a higher specific growth rate. By providing both photon energy and thermal energy to the consortia of microorganisms, a maximized growth rate will be obtained. It also shows that there are optimal wavelengths of light to encourage growth and that there is an upper level of light intensity above which growth is actually inhibited. By controlling frequency, intensity and duration, which allows the microorganisms time to recover after accepting a photon, growth will; be enhanced. The present invention addresses these needs.
U.S. Patent Applications 20050260553, 20050239182, and 20050064577, Berzin, Isaac, disclose photobioreators to containing at least one species of photosynthetic organisms to produce biogases, bioliquids and biosolids by using the nutrients from industrial emissions and combustion gases and only photon energy. This approach for bioreactor does not utilize the additional sources of energy and nutrients or take the advantages of a consortium of microorganisms to produce greater quantity of fuel feedstock.
U.S. Patent 6,395,521 discloses a process to produce hydrogen from the growth of photosynthetic organisms in a tank, such as an air-lift type, to allow for culturing to occur under light and dark conditions. This approach for bioreactor does not utilize the advantage of consortia of several different types of microorganisms that can naturally exchange energy and nutrients between the reaction zones of the consortia for optimal production of fuel feed stock and nutrient cycling within the entire community.
SUMMARY OF INVENTION
This novel open system, called the biocolumn, systematizes these consortia under man-made conditions that will maximize the rate of conversion of carbon to biomass. Subsequently, this biomass can be used directly or converted to gases, chemicals, fuels or other commercial products. Using non-fungible available and renewable thermal energy sources to drive these processes will allow them to be converted to fungible products.
As the biocolumn converts carbon into biomass, it provides means to:
1. Extract CO 2 from the atmosphere or other C02 sources like power plant emissions; 2. Effectively utilize of one or more sources of renewable energy (geothermal, waste heat, hydroelectric power, wind, and solar) ;
3. Collect and concentrate microorganisms along temperature, pH and nutrient gradients found in nature, like the ocean;
4. Photosynthesize from either natural or artificial light; and
5. Maximize the energy of chemosynthesis .
These five advantages are combined into a controlled geobiologic system and integrated in a vertical tank or a series of tanks called the biocolumn. This biocolumn, like oil and gas wells, will produce both methane gas and biomass slurry. The biocolumn is an open system allowing microorganisms and ecosystem to flourish and be maintained by a continuous flow of energy and material inputs. It is the object of this invention to provide a novel systematized bio-processor for enhancing the rapid
conversion of organic and inorganic carbon into desired products consisting of biomass, biofilms, and gases, under both aerobic and anaerobic conditions in the same, or separate vessels. The biomass, biofilms and gases are available for processing or conversion into fuels, chemicals and other high value commercial products. Also, selected gases and biomass can be processed for CO 2 sequestration .
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a diagram of a biocolumn with energy, carbon and nutrient inputs to a structure and showing outputs of product gases, liquids and solids.
FIG. 2A is a diagram of a biocolumn indicating the possible sources of energy, carbon and nutrient inputs for the biocolumn at selected zones and the possible outputs of desired product gases, liquids and solids.
FIG. 2B is a diagram of another embodiment of the biocolumn with the possible energy, carbon and nutrient inputs as well as the output of desired product gases, liquids and solids entering and leaving from the top of the column.
FIG. 3 is a diagram of another embodiment of the biocolumn shown multiple locations of carbon and nutrient inputs, as well as selective outputs product liquids.
FIG. 4 is a diagram of a biocolumn indicating temperature and pH gradients.
FIG. 5 is a diagram of the zones with the biocolumn. FIG. 6A is a diagram of single member, an microorganism, of the consortium exists within a given zone of the biocolumn.
FIG. 6B is a diagram of member microorganism of the different consortium exchange energy, carbon and nutrients along pathways between zones or through outputs of the biocolumn.
DETAILED DESCRIPTION OF THE PREFFERED EMBODIMENTS
In one embodiment, shown in FIG 1, the biocolumn is an enclosed structure that contains a column base, walls and a cap. The biocolumn can be configured like most tank structures in either a cylindrical or rectangular shapes. The biocolumn structure can be self supporting or supported. The likely height might range from 4 to 100 feet and have a diameter or diagonal between 1 and 200 feet. The biocolumn has several inputs where it can receive liquid, slurries, and gases to provide the balance of energy, nutrients and carbon sources. Another input to the biocolumn is the introduction of photons. The cap of the biocolumn may contain a translucent or transparent element in order for the photons to enter. The biocolumns may also receive photons from lights added internally and placed at specific depths. The biocolumn is also set up to harvest specific products of the biological reactions occurring within biocolumn. It is know than a vertical column of a fluid with a temperature higher on the bottom will result in the fluid on the bottom to move to the top. This invention includes features that control said movement and add meaning to thermal manage the zones, such as heat exchangers, allowing for thermal zonation to be maintained within single columns. In other embodiments, the temperature gradient might be induced to take advantage of natural convection. The outputs may consist of product gases, liquids and solids, such as methane or biomass. The
ability to add energy, carbon sources and nutrients into the biocloumn and to remove the products of the reactions and to maintain microorganism growth, allows the biocolumns to be a continuously operating open system simulating nature.
In FIG 2A, the inputs and outputs are further defined for this embodiment. The various biological reactions and microorganism growth occur at various points along the vertical height of the biocolumn. In the preferred embodiment, starting from the bottom of the biocolumn, geothermal fluids are introduced as the source of thermal energy, primary source for nutrients and secondary source of carbon through CO 2 and CH 4 gases. The biocolumn receives the discharged geothermal fluids from naturally occurring fumaroles and wells, like those found in Iceland. The geothermal fluid is water containing, but not limited to, dissolved solids and gases in varying amounts such as Silica (SiO 2 ) , Sodium (Na) , Potassium (K) , Calcium (Ca) , Magnesium (Mg), Carbonate (CC> 3 2~ ) , Sulfate (SO 4 ), Hydrogen Sulfide (H 2 S), Chloride (Cl), Fluoride (F), Iron (Fe)
Manganese (Mn) , Boron (B) , Hydrogen (H 2 ) , and Aluminum (Al) . Further up the biocolumn, a secondary source of nutrients and carbon can be introduced in the form of organic slurry. The slurry can be a mixture of water and available organic waste streams, such as carbon rich manures, organic waste, and other bio nutrients to produce near constant eutrophication conditions to further increase biomass, biofilm, and various gas productions. The slurry maybe introduced above a zone or multiple locations to allow for proper dispersion of heavier organic material through a specific zone for maximum utilized by all the microorganisms within the zone. This invention includes
other features that control said dispersion of organic material movement, so such a problem is not a concern. At the top of the biocolumn, but still below the liquid level, is the primary carbon source. The carbon comes from the introduction of air or a dedicated CO 2 source.
As the inputs flow into the biocolumn, under a controlled environment, the mixture of the various inputs will separate into five zones occupied by various microorganisms. The zone at the bottom of the biocolumn is called the reducing zone. The zone above that is the redox microtransition zone. The third zone is called the oxidizing zone. The zone above that is called the microaerophillic zone. The top zone is called aerobic zone. There is an area above the aerobic zone liquid level and beneath biocolumn cap where the product gasses can accumulate before they exit the biocolumn. The summation of these zones, or multiple microbial kingdom and species is what is called a consortium.
By placing both aerobic and anaerobic zones in a vertical column with disparate energy and heat inputs provided along the biocolumn, organic and inorganic carbon intermediates are rapidly converted into biomass, biofilms, and gases at different points along the vertical height of the column. The biocolumn combines zones of aerobic and anaerobic processes that involves multiple microbial kingdoms and species, and then exposes the microorganism to multiple energy and nutrients sources. The microorganisms will move and located themselves within five zones to meet the optimum carbon requirements, temperature, level of oxygen, order of biochemical exchange efficiency, and available waste products.
The output of the biocolumn can be in the form of gas, liquid and solid. From the bottom of the biocolumn, biomass can be removed. Moving vertically along the biocolumn, product liquids can be removed, which may be in the forms of biofllms or certain synthesized hydrocarbon liquids. Above that, product gases can be collected and drawn from the biocolumn. The gases can be, but not limited to, methane, oxygen and carbon dioxide.
The biocolumn is designed for rapid conversion of organic and inorganic carbon, into the building blocks of biologically synthesized biomass, biofilms, and gases, which are precursor substrates for the production of fuels, chemicals and other high value materials.
The biocolumn can also be configured to have the inputs and outputs enter from the top, as shown in Fig 2B. Piping can be arranged and structured to have various inputs released into specific zones at designated depths. This arrangement of piping can be set up to collect the desired products created within in certain zones. The combination of two piping arrangements, side entrance and top entrance can work as well.
Another embodiment of the biocolumn' s five zones distributed in a series of connected tanks. Each tank would contain the necessary microorganism and would be provided the required energy, carbon and nutrients inputs, along with desired isothermal condition and removal of products as end products or to be moved between the tanks.
In FIG 3, the entry point for a carbon source might have multiple locations along the vertical height of the biocolumn. Depending on the abiotic environment of the microorganism within the zones, CO 2 may have to enter the biocolumn in multiple zones and at designated depths.
Additional, the secondary nutrient source can enter the biocolumn in more than one zone and at different depths. The bio-column can also have multiply points along the vertical height of the column to remove liquid products. Certain selected products are produced within various zones and at certain depths.
In FIG 4, the operating temperature of the bio-column varies over a temperature gradient that reduces in temperature as moving upwards. The base of the bio-column may need to operate at a temperature within the range of 60 to 120°C. This will greatly depend on the temperature of the geothermal discharge that is pumped in and the type of microorganisms in the biocolumn' s consortium. Naturally occurring geothermal fluid discharge may need to be cooled by conventional mean, such as heat exchanger, before entering the biocolumn. The temperature gradient decreases through the five zones to a temperature about 40°C in the aerobic zone. The biocolumn uses the thermal energy of the geothermal or waste heat, or other sources to both drive reactions and increase the thermal gradient, there by increasing the amount vertical growth area available to specific members microorganisms while providing the optimal growth temperature and micro-environmental conditions for that species. Because each member microorganism of the consortium is symbiotically producing the requirements of another member and removing waste products of others, the biocolumn system has increased stability, flexibility, and energy efficiency over traditional bioreactor designs. It is object of this invention to utilize this consortium with simultaneous multiple carbon processing pathways and sources, multiple electron donors, and multiple electron acceptors cooperating within an open
trading symbiotic microenvironment . In FIG 6, a single member, an microorganism, of the consortium exists within a given zone of the biocolumn. Inside each zone, there is a single or multiple microorganisms that will propagate. The member microorganisms of each zone react in the presence of a carbon source and selected nutrients to form new microorganisms and form reaction products and by-products. The carbon source to sustain a member microorganism' s growth within the a zone are provided by either 1. Another member microorganism's reaction product and by-product within its zone;
2. Dead microorganisms;
3. Reaction products and by-product generated in zones above or below its level; 4. Or from an external input source.
The nutrients need to support the growth of new microorganisms are provided by either
1. Another member microorganism' s product and by- products within its zone;
2. Dead microorganisms;
3. Reaction products and by-product generated in zones above or below its level;
4. Or from an external input source.
Energy in form of, but no limited to, photons, electric fields, heat, and chemical will be along the energy pathway throughout the biocolumn. The energy sources need to support a member' s new microorganisms growth are provided either by:
1. Photons from the atmosphere entering the bio-column or generated internally;
2. Geothermal heat;
3. The endothermic heat of reaction generated by another member microorganism propagation;
4. An external energy source, such as waste heat, transfer by heat exchangers placed within the biocolumn.
An open flow of energy is needed for the biocolumn because member microorganisms at different levels require their own amount and type of energy to sustain their growth within a given zone.
Stability is further increased by the formation of biofilm, a slimy, glue-like substance that can anchors the consortia. A biofilm can be formed by a single bacterial species, but more often biofilms consist of many species of bacteria, as well as fungi, algae, protozoa, debris and corrosion products: Conventional methods of killing bacteria (such as antibiotics, and disinfection) are often ineffective with biofilm established consortia further insulating the system from varied inputs of its open architecture .
It is another novel invention to provide anchor points within the biocolumn for biofilms to anchor while the remaining internal surface area of the column provides no anchoring surface to ease harvesting. The anchor points are disengaged by the injection of hydrogen peroxide at the anchor point not to kill the bacteria but simply signal biofilm release.
The biofilm act as the control system for the consortia allowing communication between the different consortia members for self-regulation and decreasing the power requirements and system complexity.
Flexibility is therefore achieved by the consortia itself as open system energy and material inputs change the consortia continuously adapts it's various populations to balance the inputs. Also the biofilm protects the system from the shear of bubbles traveling up the length of the column further increasing stability.
All life including bacteria and archea can be categorized in terms of the microorganism's carbon and energy source. A microorganism's energy can be obtained from:
1. light reactions (phototrophs);
2. chemical oxidations of organic or inorganic substances (chemotrophs) .
A microorganism' s carbon can be obtained from:
1. CO2 (autotrophs);
2. preformed organic compounds (heterotrophs) .
The biocolumn combines all four of these types of microorganisms: phototrophs, chemotrophs, autotrophs and heterotrophs into a single integrated structure, allowing specific microorganisms to occupy highly specific microsites within the zones of the consortium according to their environmental tolerances and their carbon and energy requirements. The zones will form communities, as shown in FIG 5. Starting with the bottom of biocolumn, the reducing zone will form a community.
In the reducing zone community the following will form:
1. fermenters (vibrios) (CH 2 O)X → CO 2 + (C + R)
2. heterotrotrophs
Sulfur reducers (desulfovibrio) SO 4 2" → S 2 "
3. methogens (methonococcus) CO 2 + H 2 → C
4. iron reducers Fe 3 + Fe 2 +
In the Redox Microtransition zone community the following will form:
1. anaerobic photoanitotrophs red-green sulfur bacteria
2. heterotrotrophs anaerobic chemoautotrophs
In the Oxidizing zone community the following will form:
1. Methane oxidizers
2. Heterotrophs Denitrifiers
(pseudomonads) NO 2 " —* N 2 Sulfate reducers (desulfombrio) SO 4 2" → S 2"
3. Iron oxidizers Fe 2+ → Fe 3+
In the Microaerophilic zone community the following will form:
1. Prokaryptic chemoautotrophs a. Nitrifies
(nitrosomonos) NH 4 + → NO 2 + (nitrobacter) NO 4 + → NO 2
b. Sulfur oxidizers
(thiobacillus) S 2 " → SO 4 2" c. Methane oxidizers
(methylococcus) CH 4 + O 2 -* CO 2
In the Aerobic zone community the following will form:
1. Algaes
(Elikaryotic photoautotrophs)
2. cyanobacteria (prokaryotic photoautotrophs)
3. Heterotrophs
(vibrios)
(pseudomonades) (CH 2 O) x + O 2 → CO 2 +
Energy efficiency is achieved by the complex integration of multiple energy sources, with various consortia produced enzymes proportional to population sizes, available metallic catalysts in system fluids, and optimum growth temperatures to increase the spontaneity of each ordered biologic reactions along the length of the column. This spontaneity is referred to as the reactions Gibbs number. Gibbs numbers are cumulative therefore each reaction lowers the activation energy of the next reaction along the length of the bioreactor column. It is another novel intension of this invention is that the system further pushes the Gibbs free energy numbers to the negative by pinpointing individual reactions along the column by their consortial species location in the columns vertical space, which is controlled by thermal gradient and oxygen levels and introducing additional specific factors (i.e. electric fields) that assist or reduce the activation energy of that reaction or reactions,
and or to multiple locations, and or the total column length .
After harvesting, which can be achieved continuously or as a column is filled. It is however the intention of the invention that harvesting occur continuously in order to reduce the energy requirement as biomass, and biofilms can be removed by open fluid material flow through of the system and not additional pumping. The biomass, biofilms, and various gases from the system are delivered then processed for the production of fuels, chemicals and other high value materials or sequestration.
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