Abstract: A method of removing SO2 from a flue gas stream including SO2 includes providing a source of trona and injecting the trona into the flue gas stream. The temperature of the flue gas is between about 600° F. and about 900° F. The trona is maintained in contact with the flue gas for a time sufficient to react a portion of the trona with a portion of the SO2 to reduce the concentration of the SO2 in the flue gas stream.

Abstract: Controlling the reductive capacity of an aqueous alkaline slurry (23) in a wet scrubber makes it possible to accurately control the mercury emission from the scrubber to a desired value. One method of controlling the reductive capacity of the slurry is to measure the reduction-oxidation potential (“redox potential”) of the aqueous alkaline slurry (23) and to add or remove substances that affect the redox potential and thus the reductive capacity of the slurry. In wet scrubbers in which limestone is used for absorption of acid gases and where a gypsum slurry is circulated, it has been found to be an attractive solution to control the amount of oxidation air blown into the scrubber in order to control the redox potential and thereby the mercury emissions.

Abstract: One aspect of the invention relates to a method for removing contaminants from a flue gas stream (22). The method includes: removing fly ash from a flue gas stream (22) utilizing a particle collector (24); contacting the flue gas stream with an alkaline reagent in a wet scrubber (26); discharging a purge liquid (30) from the wet scrubber (26); combining at least a portion of the purge liquid (30) with at least a portion of the fly ash (48) to form moistened fly ash (60); and injecting at least a portion of the moistened fly ash (60) into the flue gas stream (22) upstream of the particle collector (24), whereby the moistened fly ash (60) removes at least a portion of contaminants present in the flue gas stream (22).

Abstract: Methods for scrubbing gas streams to remove acid gases including sulfur dioxide, mercury-containing substances, and/or nitrogen oxides from the gas stream. The gas stream is contacted with a potassium-based sorbent effective for removing at least a portion of the acid gases. The partially cleaned gas stream is then contacted with an oxidant effective to remove at least a portion of the nitrogen oxides and/or mercury-containing substances after partially removing the acid gas substance.

Abstract: A flue gas purification device includes a receptacle, which has an absorption zone, through which the supplied glue gas can flow in an essentially horizontal direction.

Abstract: An exhaust gas treatment system is provided that can sufficiently remove pollutants such as SO3 contained in combustion exhaust gas at low cost. In the exhaust gas treatment system for removing pollutants such as SO3 contained in combustion exhaust gas, there is provided dissolved salt aqueous solution sprays 35A, 35B, and 35C, that spray an Na2SO4 aqueous solution obtained from desulfurization effluent of a wet desulfurization system, into a flue though which the combustion exhaust gas flows.

Abstract: A method for reducing acid gases in a flue gas, the method comprising reacting biosolids comprising a scrubbing agent with a flue gas comprising an acid gas, thereby reducing the amount of acid gas in the flue gas is disclosed. Also disclosed is a flue gas scrubbing process comprising: combusting a fossil fuel and biosolids comprising a scrubbing agent, thereby producing a flue gas comprising an acid gas, wherein the flue gas has a reduced amount of acid gas compared with flue gas produced from the combustion of the fossil filet alone. A flue gas scrubbing process comprising providing a stream of biosolids that includes a hydroxide or an oxide of a Group IA or IIA element, providing a flue gas comprising an acid gas, and reacting the biosolids stream with the flue gas so as to reduce the amount of acid gas in the flue gas is also disclosed.

Abstract: Sorbent compositions for coal contain nitrogenous components that reduce the level of mercury and/or sulfur emitted into the atmosphere upon combustion. The sorbent compositions are added directly to the fuel before combustion; directly into the fireball during combustion; are added to the fuel before combustion and into the flue gas post combustion zone; or are added completely into the flue gas post combustion zone, preferably where the flue gas temperature is at least 500° C. The sorbent compositions comprise a source of nitrate ions, a source of nitrite ions, or a combination of nitrate and nitrite sources. The sorbents are added as solids or as solutions in water. In various embodiments, the sorbent compositions further comprise a source of halogen such as bromide.

Abstract: The combustion fume flowing in through line 1 is decarbonated by contacting with a solvent in column C2. The solvent laden with carbon dioxide is regenerated in zone R. The purified fume discharged through line 9 comprises part of the solvent. The method allows to extract the solvent contained in the purified fume. The purified fume is contacted in zone ZA with a non-aqueous ionic liquid of general formula Q+ A?; Q+ designates an ammonium, phosphonium and/or sulfonium cation, and A? an anion likely to form a liquid salt. The solvent-depleted purified fume is discharged through line 17. The solvent-laden ionic liquid is regenerated by heating in evaporation device DE. The solvent separated from the ionic liquid in device DE is recycled.

Abstract: A device provides the purification of flue gas comprising a scrubbing liquid sump divided into several basins and a pump device, which pumps the scrubbing liquid from at least one basin of the scrubbing liquid sump to scrubbing liquid nozzles.

Abstract: A method of removing SO3 from a flue gas of a boiler. The method includes the following steps: injecting chloride salts into a stream of the flue gas at a position located downstream of an air pre-heater—the position is selected so that the flue gas has a temperature at the position of substantially between 100° C. and 400° C.; reacting chloride salts with the SO3 to form a sulfate-containing reaction product; and collecting the sulfate-containing reaction product in a particulate collector downstream of the boiler. A purge stream from a wet flue gas desulfurization system may be used as a source of the chloride salts. Additional chlorides may be added to the purge stream as necessary.

Abstract: A method of reducing sulfur dioxide emissions of a circulating fluidized bed boiler. Sulfur-containing carbonaceous fuel is fed to a furnace of the boiler, and calcium carbonate is fed to the furnace at a rate relative to the first stream such that the molar ratio of calcium in the second stream to sulfur in the first stream is at most about 1.0. The fuel is combined so that the sulfur is oxidized to form sulfur dioxide. The calcium carbonate is calcined to form calcium oxide and the calcium oxide is used to sulfate the sulfur dioxide to form calcium sulfate. Flue gas particles are separated using a hot loop separator, and the separated particles are returned to the furnace. A sulfur-reduction stage downstream of the furnace further reduces the sulfur content of the flue gases.

Abstract: The gaseous effluent flowing in through line 1 is contacted in absorption zone ZA with the liquid absorbent solution flowing in through line 9. The gaseous effluent depleted in acid compounds is discharged through line 2. The absorbent solution laden with acid compounds is discharged through line 3. The absorbent solution once laden with acid compounds comprises two phases: a first phase poor in acid compounds and a second phase rich in acid compounds. The two phases are separated in zone ZS. The first phase is recycled through lines 5 and 9 to absorption zone ZA. The second phase is fed through line 4 into regeneration zone ZR. In zone ZR, the acid compounds are separated from the absorbent solution. The acid compounds are discharged through line 7. The regenerated absorbent solution is recycled through lines 6 and 9 to zone ZA.

Abstract: The invention provides a process for the removal of polysulfanes from gas streams formed during H2S synthesis.

Abstract: A process for the removal of pollutants from a combustion process and, more particularly, a process for removing pollutants such as carbon dioxide, mercury, sulphur dioxide, nitrogen compounds and oxygen compounds from a combustion process. The process includes the removal of pollutants from a combustion process that produces an emission comprising: cooling the emission to a temperature of about 200° C.; removing nitrogen, water and oxygen from the emission to produce a gas containing a concentration of pollutants; contacting the gas with an aqueous magnesium chloride solution, wherein a slurry mixture is formed; and cooling the gas and the slurry mixture, wherein hydrochloric acid vapour and a sludge are formed.

Abstract: A method for removing impurities accumulated in a scrubbing fluid in a flue gas scrubber and effluents from the scrubber. The flue gases are scrubbed with a scrubbing fluid that includes a calcium-containing absorbent. The scrubbing fluid containing gypsum and other impurities and produced in the scrubber is discharged from the scrubber. The gypsum is separated from the scrubbing fluid. To the scrubbing fluid is added an auxiliary agent, by the effect of which the impurities accumulated in the scrubbing fluid are removed with the gypsum and the moisture content of the gypsum to be separated from the scrubbing fluid is increased.

Abstract: A process and system for removing sulfur oxide, other gases, and particulate from a flue gas. The process includes treating flue gas with a slurry formed from water, an alkaline reagent, and the purge stream from a wet scrubber in a spray dryer, thereby producing a dry by-product. The process further includes filtering the flue gas to remove at least a portion of the dry by-product, wet scrubbing the flue gas exiting the filter in a wet scrubber, adding a lime or limestone reagent to the wet scrubber, and producing gypsum. Activated carbon may be injected into the flue gas upstream of the filtering step and particulate may be removed from the flue gas upstream of the spray dryer.

Abstract: NOx and SO3 emissions from combustion of a sulfur containing carbonaceous fuel are reduced simultaneously. The combustion gases comprising NOx and SO2 are mixed with a NOx control agent into the combustion gases at a point upstream of a selective catalytic reduction catalyst for reduction of NOx. Following an SCR catalyst or other equipment that can oxidize SO2 to SO3 and prior to contact with an air heater for heating incoming combustion air, magnesium hydroxide is introduced in amounts and with droplet sizes and concentrations effective to form nano-sized particles in the effluent and reduce SO3 caused by the oxidation of SO2 in the catalyst. Computational fluid dynamics is employed to determine flow rates and select reagent introduction rates, reagent introduction location(s), reagent concentration, reagent droplet size and/or reagent momentum.

Abstract: A method for processing flue gas scrubber material flows. The flue gas is scrubbed with a calcium-based absorbent containing washing fluid for absorbing sulphur oxides from the flue gases, and the formed gypsum slurry is directed from the flue gas scrubber to the separator. At the separating point of the separator, gypsum is separated from the washing fluid and the gypsum and washing fluid are taken out of the separator as separate material flows. From the flue gas scrubber the washing fluid is directed to a tank located before the separating point of the separator or after the separating point of the separator, in which tank foam is separated from the washing fluid as its own phase and taken out of the tank.

Abstract: A scoop is used to collect a liquid slurry upstream of an internal collection tank. The scoop is in fluid communication with a downcomer, which receives at least part of the collected slurry, thereby maintaining a continuous flow of liquid slurry through the scoop to prevent plugging. Collected slurry can be removed for treatment from the scoop or the downcomer. In an application to a wet flue gas desulfurization (FGD) scrubber, the scoop collects an effluent slurry of partially reacted liquid scrubbing reagent and scrubbing byproducts before they drain into an internal reaction tank. Partially reacted liquid scrubbing reagent and scrubbing byproducts can therefore be withdrawn for treatment before the addition of fresh reagent alters the pH of the treatment stream.

Abstract: The invention relates to a method and an installation for separating sulphur dioxide from exhaust gas, wherein sea water is added to the exhaust gas in an absorption column and the sea water charged with sulphur compounds is extracted from the liquid sump of the absorption column and fresh sea water is added thereto. In order to omit the very expensive and large secondary reaction basis according to the state of the art, it is proposed to extract the liquid, which contains the bisulphates, from the liquid sump of the absorption column and to mix it with fresh sea water in a pipeline for the purpose of sulphate formation and pH adjustment (neutralization). The invention is based upon the finding that the sulphate formation and pH adjustment are completed after a reaction time comprised between 1 and 2 minutes. Thus, the large and expensive secondary reaction basin can be omitted.

Abstract: An improvement to the melt transesterification process for the preparation of polycarbonate is disclosed. The improvement entails adding to the process between its medium viscosity reactor and a high viscosity reactor at least one bridged ester of organic sulphur-containing acid.

Abstract: A process to regenerate wet flue gas scrubber purge liquid into NaOH caustic suitable for make-up caustic for the scrubber is disclosed. Further, sulfur is removed from waste effluent in the form of gypsum with the process described herein. Lime is added to the spent, sodium sulfate-containing purge liquid to result in the formation of gypsum and sodium hydroxide.

Abstract: An apparatus for removing constituents from a fluid stream is provided. The apparatus includes a duct, a collection device, a sorbent injector, and an acoustic generator. The duct has a fluid passageway to receive a fluid stream having constituents. The collection device filters the fluid stream. The sorbent injector injects a sorbent in the fluid passageway of the duct. The acoustic generator generates an acoustic field in the fluid passageway of the duct to promote sorption of the constituents for collection by the collection device. Additionally, a method is provided for removing constituents from a fluid stream.

Abstract: The present invention provides methods and apparatus for treating flue gas containing sulfur dioxide using a scrubber, and more particularly relates to recovering gypsum and magnesium hydroxide products from the scrubber blowdown. The gypsum and magnesium hydroxide products are created using two separate precipitation reactions. Gypsum is crystallized when magnesium sulfate reacts with calcium chloride. Magnesium hydroxide is precipitated when magnesium chloride from the gypsum crystallization process reacts with calcium hydroxide. The process produces a high quality gypsum with a controllable pH and particle size distribution, as well as high quality magnesium hydroxide.

Abstract: A device (1) for separating sulphur dioxide from a gas (4) by means of an absorption liquid has an inlet (2) for gas (4) containing sulphur dioxide, an outlet (18) for gas (16), from which sulphur dioxide has been separated, and as essentially horizontal apertured plate (8), which is arranged to allow passage from below of sulphur dioxide containing gas (4) and to carry, on its upper side (12), a flowing layer (14) of the absorption liquid. An outlet box (20) beside the apertured plate (8) is arranged to be passed by liquid, which is distributed in the gas (4) coming from the inlet (2). A first pumping means is arranged to feed a coolant flow to the outlet box (20) and a second pumping means is arranged to feed an absorption liquid flow, which is essentially independent of the coolant flow, to the apertured plate (8) to form the flowing layer (14). In a method of separating sulphur dioxide, the above-described device (1) can be used.

Abstract: A device (1) for separating sulphur dioxide from a gas has an inlet (2) for the gas (4) and an outlet (42) for gas (40), from which sulphur dioxide has been separated. An apertured plate (20) is arranged between the inlet (2) and the outlet (42) and allows the gas (4) to pass from below. On its upper side (22), the apertured plate supports a flowing layer (24) of absorption liquid. An inlet duct (12) connects a container (6) for absorption liquid to the upper side (22) of the apertured plate (20). A means (10) conveys the absorption liquid (8) from the container (6), through the inlet duct (12), to the upper side (22) of the apertured plate (20) and along the apertured plate (20).

Abstract: A process and apparatus for removing SO2, NO, and NO2 from a gas stream having the steps of oxidizing a portion of the NO in the flue gas stream to NO2, scrubbing the SO2, NO, and NO2 with an alkali scrubbing solution, and removing any alkali aerosols generated by the scrubbing in a wet electrostatic precipitator. The process can also remove Hg by oxidizing it to oxidized mercury and removing it in the scrubbing solution and wet electrostatic precipitator. Alkali sulfates, which are valuable fertilizers, can be withdrawn from the rubbing solution.

Abstract: A process and apparatus for removing SO2, NO, and NO2 from a gas stream having the steps of oxidizing a portion of the NO in the flue gas stream to NO2, scrubbing the SO2, NO, and NO2 with an ammonia, ammonium hydroxide, alkali hydroxide or carbonate scrubbing solution, regenerating the scrubbing solution with limestone, and removing any particulate matter and aerosols generated by the scrubbing step in a wet electrostatic precipitator. The process can also remove Hg by oxidizing it to oxidized Hg and removing it in the wet electrostatic precipitator. The scrubbing solution is preferably regenerated with limestone or magnesium, and results in a Group II sulfite or sulfate that can be recovered and sold, or landfilled.

Abstract: A water stream containing hardness minerals is subjected to a water treatment process using an alkali agent to precipitate the hardness minerals and to produce a softened water stream is used to create an integrated water treatment and flue gas desulfurization process. Thereafter, the softened, alkaline water stream is utilized in a scrubber to scrub a flue gas containing sulfur dioxide to produce a sulfur-lean flue gas. The invention may be applied to a steam-based bitumen recovery operation where bitumen, sour produced gas or other sulfur containing fuels are burned for producing steam for bitumen recovery. More specifically, the associated produced water from the bitumen recovery process may be softened for re-use and for utilization as a scrubbing agent for high-sulfur containing flue gas arising from the steam generators. The process provides an economically favorable process while minimizing waste disposal requirements.

Abstract: A multiple-field precipitator, flue-gas treating device, in accordance with the principles of the invention, includes a first section having a dual-function, sensible-cooling heat exchanger/electrostatic precipitator, a second section having a wet electrostatic precipitator, and a middle section fluidly connecting the first and second sections. In the first section, the exchanger/precipitator sensibly cools the flue gas and collects most of the dust from the flue gas. In the middle section, the dust-reduced flue gas is combined with an alkaline material, thereby forming reaction products. These reaction products and several other pollutants are captured by the wet electrostatic precipitator, in the form of a pollutant-laden liquid. The pollutant-laden liquid is directed to a series of heat exchangers and settling tanks, where various pollutants such as SOx, metals, NOx, and chlorides are removed in different stages.

Abstract: A process for controlling both fireside ash deposits and corrosion, and fouling, corrosion, and emissions due to SO3 formation within a fossil-fuel-fired combustion system, such as a furnace forming part of an electrical power generating plant. A solution of a soluble magnesium compound, which can be derived from wastes, such as the bleed stream from the power plant's SO2 scrubber, is injected into the combustion products within the furnace in the form of a fine spray and at a point at which the temperature is sufficiently high to produce submicron-size MgO particles. The SO3 reacts with the MgO particles to form MgSO4. Insoluble magnesium compounds can be added to the solution to produce larger (micron sized) MgO particles on thermal decomposition. The micron-sized MgO particles are deposited on furnace surfaces to reduce ash deposits and to reduce catalytic generation of SO3. The boiler wastes can be reacted with other industrial process waste products to provide marketable chemicals.

Abstract: The present invention describes a procedure for the removal of sodium sulphate from a phosphate solution that has been used for absorption of SO2 from flue gases, in which a precipitate forms when the absorption solution is regenerated by evaporation. In this procedure a part of the precipitate is separated from its solution and treated with water and SO2 for transformation of disodium-hydrogen phosphate into monosodium dihydrogen phosphate in the aqueous solution. The sodium sulphate remains undissolved and is removed by filtration. The filtrate is then added back to the main process.

Abstract: A calcium hydroxide slurry is injected into the off gases in the exhaust duct of an industrial plant which burns sulfur containing fuels. The calcium hydroxide slurry reacts with SO3 produced as a result of the combustion process and forms a primary solid calcium sulfate reaction product. The calcium sulfate can then be removed in a particulate removal station in the plant.

Abstract: The present invention provides a method for the treatment of mercury present in exhaust gas wherein, after a chlorinating agent is added to exhaust gas containing nitrogen oxides, sulfur oxides and mercury, the exhaust gas is subjected to a reductive denitration treatment in the presence of a solid catalyst and then to wet desulfurization using an alkaline absorbing fluid, the method being characterized by measuring the mercury concentration in the exhaust gas after the wet desulfurization; calculating a predicted value of the inlet mercury concentration before the reductive denitration treatment on the basis of the measured mercury concentration; and controlling the feed rate of the chlorinating agent added prior to the reductive denitration treatment, according to the deviation of the predicted value from a reference inlet mercury concentration, as well as a system for the treatment of exhaust gas.

Abstract: A system for removal of Hydrogen Sulfide (H2S) and/or Carbon Dioxide (CO2) from natural gas via absorption and disassociation utilizing a sea water contact system. In the preferred embodiment of the present invention, a series of counter current scrubber stages is provided, each configured to remove via absorption/disassociation a portion of the impurities, each stage having less pressure than the predecessor, each stage redirecting the purified gas to the preceding stage, until the contaminant level in the hydrocarbon gas stream has been reduced to an acceptable level. The hydrogen sulfide/carbon dioxide contaminants are thereby sequestered in the sea water utilized in the scrubber, which sea water may be further processed and/or re-introduced into the deep of a body of water, where the contaminants will remain isolated for hundreds of years. The present invention further contemplates and energy recovery system for greatly enhancing the efficiency of the system.

Abstract: In a flue gas treating system, an absorption tower (21), a reheating section (22) and a fan (23) are arranged in line on a vertical axis so as to function as at least a part of a stack for emitting the treated flue gas into the atmosphere. Moreover, in a flue gas treating process, the amount of ammonia injected in the denitration step (a denitrator (2)) and/or the amount of ammonia at a point downstream of the denitration step are determined so as to be on such an excessive level that ammonia or ammonium salt will remain in the flue gas introduced into the desulfurization step (absorption tower (21)). Thus, the size and cost of the equipment can be reduced.

Abstract: A system for reducing the temperature of exhaust gas in an incinerator or boiler equipment having an exceedingly small size and avoiding any difficulties caused by damage to the wall surface of a gas cooling chamber due to adherence of sprayed water droplets and deposition of dust. More specifically, pressurized thermal water with a temperature higher than a boiling point of water under atmospheric pressure is sprayed as temperature reduction water into high temperature exhaust gas Gh in a gas cooling chamber or an exhaust gas duct. The temperature reduction of exhaust gas and the removal of acidic gas in the exhaust gas are simultaneously achieved by spraying pressurized thermal water Wt containing an alkaline solution as temperature reduction water into high temperature exhaust gas Gh in the gas cooling chamber or the exhaust gas duct.

Abstract: A system for reducing the temperature of exhaust gas in an incinerator or boiler equipment having an exceedingly small size and avoiding any difficulties caused by damage to the wall surface of a gas cooling chamber due to adherence of sprayed water droplets and deposition of dust. More specifically, pressurized thermal water with a temperature higher than a boiling point of water under atmospheric pressure is sprayed as temperature reduction water into high temperature exhaust gas Gh in a gas cooling chamber or an exhaust gas duct. The temperature reduction of exhaust gas and the removal of acidic gas in the exhaust gas are simultaneously achieved by spraying pressurized thermal water Wt containing an alkaline solution as temperature reduction water into high temperature exhaust gas Gh in the gas cooling chamber or the exhaust gas duct.

Abstract: A calcium hydroxide slurry is injected into the off gases in the exhaust duct of an industrial plant which burns sulfur containing fuels. The calcium hydroxide slurry reacts with SO3 produced as a result of the combustion process and forms a primary solid calcium sulfate reaction product. The calcium sulfate can then be removed in a particulate removal station in the plant.

Abstract: A process of using sodium carbonate and sodium bicarbonate solutions to remove SO3 and other acidic gases or vapors from a flue gas without substantially decreasing the amount of sulfur dioxide also present in the flue gas. Very limited quantities of such solutions are injected into the flue gas in a manner that achieves a controlled droplet size, such that the solution dries on contact with the flue gas and the resulting dry particles of sodium carbonate/bicarbonate are sufficiently small as to have adequate surface area for reacting with SO3, as well as any H2SO4 and, to some extent, HCl vapors in the flue gas.

Abstract: A method for removing an acidic component such as sulfite gas (SO2) contained in an exhaust gas comprising by using a system comprising (a) a gas-liquid contact apparatus composed of an absorption column provided internally with at least one perforated plate at the top, bottom, or both top and bottom of the absorption column packed with at least one type of fillers, (b) an apparatus for introducing raw seawater to the absorption column, (c) an apparatus for oxidizing the seawater after gas-liquid contact, and (d) an apparatus for mixing raw seawater with the contact seawater after oxidation, whereby the exhaust gas containing an acidic component is brought into gas-liquid contact with the seawater.

Abstract: Denitrated combustion exhaust gas is desulfurized with ammonia, the waste water obtained from washing the desulfurization waste water or dust ash is filtered using calcium carbonate, the pH of the filtrate is adjusted, carbon dioxide and/or aqueous carbonic acid is added and then a flocculating agent is added, and ammonia is recovered from the supernatant after precipitation and separation of the solid portion. The recovered ammonia is added to the denitrated gas for treatment of the combustion exhaust gas.

Abstract: The liquid cooling spray in a gas conditioning chamber is modified by the addition of an alkali to scrub sulfuir dioxide and other acid forming gases and a separation unit to remove particles that may contain either unreacted alkali or salts of the acid forming gases. A slurry of fine particles of hydrated lime is injected into the liquid coolant under conditions that result in kernels of controllable size that contain the alkali or salts from reactions with the acid forming gases. The modified cooling liquid provides for a high sulfur dioxide collection efficiency at a low molar ratio of alkali to sulfur, while the specified kernel size range allows fbr efficient removal of the kernels from the gas.

Abstract: A calcium hydroxide slurry is injected into the off gases in the exhaust duct of an industrial plant which burns sulfur containing fuels. The calcium hydroxide slurry reacts with SO3 produced as a result of the combustion process and forms a primary solid calcium sulfate reaction product. The calcium sulfate can then be removed in a particulate removal station in the plant.

Abstract: The method of simultaneously reducing carbon dioxide (CO2) emissions and sulfur dioxide (SO2) emissions produced by the combustion of carbon-containing matter in a hearth consists in injecting into the hearth a calcium-based agent, a fraction of which absorbs SO2 after decarbonization, and then, after the flue gases have been subjected to intermediate cooling, in causing them to transit via a first reactor and in putting them in contact therein with the other fraction of the absorbant that has not reacted with SO2 so as to capture CO2 from the flue gases by carbonization, then, in a separator, in extracting the solids contained in the flue gases output from the first reactor so as to subject them to heat treatment in a second reactor in order to extract CO2 therefrom by decarbonization and in order to recycle the resulting regenerated CO2 absorbant to the first reactor.

Abstract: A system for reducing the temperature of exhaust gas in an incinerator or boiler equipment having an exceedingly small size and avoiding any difficulties caused by damage to the wall surface of a gas cooling chamber due to adherence of sprayed water droplets and deposition of dust. More specifically, pressurized thermal water with a temperature higher than a boiling point of water under atmospheric pressure is sprayed as temperature reduction water into high temperature exhaust gas Gh in a gas cooling chamber or an exhaust gas duct. The temperature reduction of exhaust gas and the removal of acidic gas in the exhaust gas are simultaneously achieved by spraying pressurized thermal water Wt containing an alkaline solution as temperature reduction water into high temperature exhaust gas Gh in the gas cooling chamber or the exhaust gas duct.

Abstract: A method for the combined reduction of sulfur dioxide, SO2, and nitrogen oxides, NOx, in the gas stream of a furnace from the combustion of fossil fuels is disclosed. In a narrow gas temperature zone in a furnace, NOx is converted to nitrogen by reaction with a reducing agent such as urea or ammonia with negligible residual ammonia and other reaction pollutants. In about this same temperature zone, SO2 will react with calcium oxide particles, derived from the calcination of lime, Ca(OH)2, or limestone, CaCO3, to form CaSO4 particles. A wide size distribution of aqueous droplets, containing dispersed lime or very fine limestone particles and dissolved urea or ammonia, is injected at the outer edge of the furnace gas zone at which the SO2 and NOx reduction reaction are effective.

Abstract: The liquid cooling spray in a gas conditioning chamber is modified by the addition of an alkali to scrub sulfur dioxide and other acid forming gases and a separation unit to remove particles that may contain either unreacted alkali or salts of the acid forming gases. A slurry of fine particles of hydrated lime is injected into the liquid coolant under conditions that result in kernels of controllable size that contain the alkali or salts from reactions with the acid forming gases. The modified cooling liquid provides for a high sulfur dioxide collection efficiency at a low molar ratio of alkali to sulfur, while the specified kernel size range allows for efficient removal of the kernels from the gas.

Abstract: The present invention is a method of solidifying sulfur component being the cause of “SOx poisoning” by use of a sulfur solidifier. The solidifier includes a metal element having a function of oxidizing the sulfur component and a basic metal element. And the solidifier solidifies sulfur component before exhaust gas flows into an NOx-occluding reduction-type exhaust purifying catalyst located on an exhaust path. Since the foregoing sulfur solidifier includes the above metal element and the basic metal element, it can effectively solidify the sulfur component which are the cause of the SOx poisoning, and ensure improvement in purification performance.