Abstract: This invention provides a process for effecting desulfurization and decarbonation in two stages. A gas containing sulfur oxides and carbon dioxide is first treated in a desulfurization step so as to cause sulfur oxides to be absorbed in the form of calcium-sulfur oxide compounds; the gas is then treated in a decarbonation step so as to cause carbon dioxide and any sulfur oxides escaping from the desulfurization step to be absorbed in the form of amine salts; the absorbing solution containing the amine salts is regenerated by liberating carbon dioxide therefrom; a part of the regenerated absorbing solution is recycled to the decarbonation step while the remainder of the absorbing solution is fed to a secondary regeneration step where it is treated with a basic calcium substance to regenerate basic amine compound for recycle and to form a solid containing calcium-sulfur oxide compounds and calcium carbonate.

Abstract: A flue gas desulfurizer having an absorption tower for bringing untreated flue gas into gas-liquid contact with an absorbent slurry, wherein there is provided heat recovery means for recovering heat from the flue gas passing through the flue gas inlet section of the absorption tower prior to gas-liquid contact, and to boiler equipment including heat release means for releasing the recovered heat to heat utilization equipment. This invention also relates to thermal electric power generation equipment including extraction feedwater heaters for heating boiler feedwater with steam from steam turbines, a flue gas desulfurizer using an absorbent slurry, and means for recovering heat from the flue gas passing through the flue gas desulfurizer and/or the absorbent slurry within the flue gas desulfurizer, whereby boiler feedwater is preheated by the recovered heat and then introduced into the extraction feedwater heaters.

Abstract: This invention relates to a process for removing highly concentrated CO.sub.2 from high-pressure natural gas and recovering it in a high-pressure state.This process comprises the absorption step of bringing high-pressure natural gas having a CO.sub.2 partial pressure of 2 kg/cm.sup.2 or greater and a pressure of 30 kg/cm.sup.2 or greater into gas-liquid contact with a regenerated CO.sub.2 -lean absorbing fluid comprising a CO.sub.2 absorbing fluid of which the difference in saturated CO.sub.2 absorption level between 40.degree. C. and 120.degree. C. is not less than 30 Nm.sup.3 per ton of solvent at a CO.sub.2 partial pressure of 2 kg/cm.sup.2, whereby highly concentrated CO.sub.2 present in the high-pressure natural gas is absorbed into the CO.sub.2 -lean absorbing fluid to produce refined natural gas having a reduced CO.sub.2 content and a CO.sub.2 -rich absorbing fluid; and the regeneration step of heating the CO.sub.2 -rich absorbing fluid without depressurizing it, whereby high-pressure CO.sub.

Abstract: After hydrogenation and desulfurization treatment of raw fuel in the desulfurization unit 1, the product is separated in the acidic gas separator 2 into fuel and a hydrogen sulfide-containing gas, and the hydrogen sulfide-containing gas is subjected to combustion together with air in the catalyst converter 3 thereby converting the hydrogen sulfide completely into sulfur dioxide to give a sulfur dioxide-containing gas, and this sulfur dioxide-containing gas is reacted with limestone powder and air in water in the oxidation and neutralization reactor 4, and the resulting slurry is dehydrated in the gypsum slurry solid/liquid separator 5 and then dried in the gypsum heater 6.

Abstract: This invention relates to methods for the removal of hydrogen sulfide from various gases containing hydrogen sulfide. In order to remove hydrogen sulfide, an aqueous solution containing a di(lower alkyl)amino-(lower alkanol) or triethylenediamine is used. In order to remove hydrogen sulfide selectively from gases containing carbon dioxide and hydrogen sulfide, an aqueous solution containing tert-butyldiethanolamine, triisopropanolamine, triethylenediamine or 2-dimethylamino-2-methyl-1-propanol is used. In order to remove both carbon dioxide and hydrogen sulfide from gases containing carbon dioxide and hydrogen sulfide, an aqueous solution containing a mono(lower alkyl)amino-(lower alkanol) is used.

Abstract: This invention provides a method for the removal of CO.sub.2 present in combustion exhaust gas which comprises bringing combustion exhaust gas at atmospheric pressure into contact with a mixed aqueous solution containing 100 parts by weight of an amino acid metal salt (X), 1 to 25 parts by weight of piperazine (Y), and optionally a copper compound in such an amount as to give a divalent copper ion concentration of 10 to 1,000 ppm based on the mixed aqueous solution, the amino acid metal salt being of the general formulaCH.sub.3 NR.sup.1 CHR.sup.2 COOM (1)wherein R.sup.1 and R.sup.2 represent hydrogen atoms or lower alkyl groups, provided that R.sup.2 is a lower alkyl group when R.sup.1 is a hydrogen atom, and R.sup.2 is a hydrogen atom when R.sup.1 is a lower alkyl group, and M represents an alkali metal.Potassium dimethylaminoacetate is a preferred amino acid metal salt (X).

Abstract: This invention relates to a process for the removal of carbon dioxide from gases which comprises the carbon dioxide absorption step of bringing a gas having a carbon dioxide partial pressure in the range of 0.3 to 50 atmospheres (absolute pressure) into gas-liquid contact with an absorbing fluid comprising an aqueous solution containing an amine compound of the general formula ?1!R.sup.1 R.sup.2 NCH.sub.2 CH(OH)CH.sub.2 OH ?1!where R.sup.1 and R.sup.2 independently represent lower alkyl groups of 1 to 3 carbon atoms, so as to produce a treated gas having a reduced carbon dioxide content and a carbon dioxide-rich absorbing fluid; and the regeneration step of liberating carbon dioxide from the carbon dioxide-rich absorbing fluid by (1) flashing at atmospheric pressure or in the vicinity of atmospheric pressure and/or (2) steam stripping, so that a carbon dioxide-lean absorbing fluid is regenerated and recycled for use in the carbon dioxide absorption step.

Abstract: A method for removing carbon dioxide from a combustion exhaust gas under atmospheric pressure by the use of a mixed solution of a specific amine compound X having an alcoholic hydroxyl group and a primary amino group which is bonded to a tertiary carbon atom having two unsubstituted alkyl groups and another amine compound Y being a diaminotoluene (DAT) selected from the group consisting of 2,3-DAT, 2,4-DAT, 2,5-DAT, 2,6-DAT, 3,4-DAT and 3,5-DAT.

Abstract: A process for removing both CO.sub.2 and NO.sub.x from combustion gases consists, first, in cooling a combustion gas to 50 to 100.degree. C. and adding ozone to oxidize NO in the combustion gas to NO.sub.2. Then in a CO.sub.2 removal step, the gas is brought into contact with an aqueous solution of an alcoholic hydroxyl-containing secondary- or tertiary-amine to remove NO.sub.2 together with CO.sub.2 from the gas.

Abstract: This invention relates to the process for removing CO.sub.2 from CO.sub.2 -containing gas such as combustion gas. For example, it is the process for removing CO.sub.2 from combustion gas through the contact of the gas at the atmospheric pressure with an aqueous solution of an amine represented by the general formula R.sup.1 NHC(CH.sub.3).sub.2 CH.sub.2 OH in which R.sup.1 is a lower alkyl group having 1-4 carbon atoms, or an aqueous solution containing both an amine represented by the general formula R.sub.2 CHR.sub.3 NHCH.sub.2 CH.sub.2 OH in which R.sup.2 is a hydrogen atom or a lower alkyl group having 1-4 carbon atoms and R.sup.3 is a hydrogen atom or methyl group and a piperazine compound selected from the group consisting of piperazine, 2-methylpiperazine, 2,3-dimethylpiperazine, and 2,5-dimethylpiperazine, or an mixed aqueous amine solution containing a secondary amine and a tertiary amine at concentrations of 10-45% by weight each, or an aqueous solution of a piperazine derivative.

Abstract: This invention relates to methods for the removal of hydrogen sulfide from various gases containing hydrogen sulfide. In order to remove hydrogen sulfide, an aqueous solution containing a di(lower alkyl)amino-(lower alkanol) or triethylenediamine is used. In order to remove hydrogen sulfide selectively from gases containing carbon dioxide and hydrogen sulfide, an aqueous solution containing tert-butyldiethanolamine, triisopropanolamine, triethylenediamine or 2-dimethylamino-2-methyl-1-propanol is used. In order to remove both carbon dioxide and hydrogen sulfide from gases containing carbon dioxide and hydrogen sulfide, an aqueous solution containing a mono(lower alkyl)amino-(lower alkanol) is used.

Abstract: A heat pipe includes: a pipe barrel; and a large number of fins disposed on the peripheral surface of the pipe barrel at least on either a heat collecting section side or a radiating section side, each of the fins is attached to the pipe barrel on a plane perpendicular to the axis of the pipe barrel, and each of the fins is composed of a metal plate and net-like material adhered to both surfaces of the metal plate.A heat exchanger of gas-liquid contacting plate type includes: a plurality of heat transfer plates, disposed vertically at certain intervals, defining air flow passages therebetween which allow air to rise, and each of the plates has a heat medium flowing passage thereinside for allowing a heat medium to flow therethrough while the side surfaces of each of the heat transfer plates, which define the air flow passages, are adhered with nets for allowing a liquid to flow downward along the nets and plates.

Abstract: A process for removing CO.sub.2 from a combustion gas which comprises removing CO.sub.2 from the combustion gas through contact of an aqueous hindered amine solution used as a CO.sub.2 absorbent solution with the combustion gas at atmospheric pressure and then, in a regeneration column, liberating CO.sub.2 from the absorbent solution that has absorbed CO.sub.2 by heating it and thereby regenerating the absorbent solution. The process further comprises a partial absorbent solution regeneration step in at least one stage wherein the absorbent solution that has absorbed CO.sub.2 is heated through heat exchange with a high-temperature regenerated absorbent solution and part of the CO.sub.2 that is liberated is separated from the absorbent solution. Following this, according to the necessity, part of the partially regenerated absorbent solution thus obtained is returned to the step of removing CO.sub.2 from the combustion gas for use as part of the CO.sub.

Abstract: An apparatus for gas-liquid contact in which tubular structure fillers having a cross section of any of various shapes and having straight tubular portions are arranged in a substantially vertical direction in the form of plural steps so that the gas-liquid contact surfaces of the fillers may be parallel with the flow of the gas,the apparatus for gas-liquid contact being characterized in that the gas-liquid contact surfaces comprise rough surface portions, porous surface portions, meshes or plates to which meshes adhere, or there is interposed, between the plural steps of the fillers, a dispersing plate for receiving the liquid downward coming from the site above the fillers, dispersing the liquid, and allowing the liquid to downward flow.

Abstract: A process for the disposal of carbon dioxide in deep sea, which comprises compressing and dehumidifying gaseous carbon dioxide to be disposed of, passing the so compressed carbon dioxide gas through a cold sea water region where a temperature condition enough to liquefy the compressed carbon dioxide gas prevails via a pipe line to effect cooling of the gas by heat exchange with the cold sea water to thereby liquefy the compressed carbon dioxide gas, conducting the liquefied carbon dioxide through an extension of the pipe line to such a depth of sea water, that the specific weight of the liquefied carbon dioxide at such depth is greater than that of the ambient sea water of such depth, and then discharging out the liquefied carbon dioxide into such deep sea.

Abstract: A method for recovering carbon dioxide by absorbing carbon dioxide present in a combustion exhaust gas using an aqueous alkanolamine solution, comprising the step of bringing a combustion exhaust gas from which carbon dioxide has been absorbed and removed into contact with water containing carbon dioxide. A method for treating a combustion exhaust gas for denitration using ammonia as a reducing agent and for removal of carbon dioxide by absorption with an aqueous alkanolamine solution, which method comprising the steps of recovering ammonia present in the combustion exhaust gas after the carbon dioxide removal, and using the recovered ammonia as a reducing agent for the denitration. A method for removing CO.sub.2 from a combustion exhaust gas comprising the step of bringing the combustion exhaust gas into contact under atmospheric pressure with an aqueous monoethanolamine solution having a concentration of 35% by weight or more.

Abstract: Disclosed are a method for the fixation of carbon dioxide which is characterized by the steps of bringing carbon dioxide and seawater or fresh water into contact with each other at a temperature and a pressure required for the formation of carbon dioxide hydrate, and sinking it in the seawater or fresh water satisfying certain conditions for the stability of carbon dioxide hydrate; a method for the fixation of carbon dioxide which uses a pressurized pipeline for producing and cooling the hydrate and releases the product hydrate at a position in the sea where the hydrate can remain stable; an apparatus for fixing and dumping carbon dioxide which is disposed in seawater or fresh water satisfying certain pressure and temperature conditions for the formation of carbon dioxide hydrate and which comprises a container for producing carbon dioxide hydrate, and a discharge means for discharging the hydrate produced out of the container; and an apparatus for the treatment of carbon dioxide which comprises a reaction de

Abstract: A process for removing carbon dioxide (CO.sub.2) from a combustion exhaust gas of a boiler (1) which generates steam for driving high (3), intermediate (7), and low (8) pressure turbines. The process comprises the steps of removing CO.sub.2 in the combustion exhaust gas by absorption with a CO.sub.2 -absorbing liquid (19), liquefying the removed CO.sub.2 (28) by compression (42) and cooling (48), storing (52) the CO.sub.2, and regenerating the CO.sub.2 -absorbing liquid by a CO.sub.2 -absorbing liquid regeneration column (24) equipped with a reboiler (30). In the process, a part (40) of steam discharged from the high pressure turbine (3) is used to drive turbines (41, 43) for compressors (42, 44) that compress the CO.sub.2, and a refrigerant for cooling the CO.sub.2, and steam (45) discharged from the compressor turbines is supplied as a heating source to the reboiler (30) for the regeneration of the CO.sub.2 -absorbing liquid.

Abstract: An electric generating power plant and a method of operation thereof wherein the boiler (1) produces steam to a turbine driven-generator (2), carbon dioxide from combustion exhaust gas emitted from the boiler is simultaneously absorbed in an absorbing solution in an absorber (7), the absorbing solution with the absorbed carbon dioxide is passed through a regenerator (10) where the carbon dioxide is stripped from the absorbing solution, the regenerated absorbing solution is returned to the absorber (7), and steam from either the boiler (1) or turbine of the turbine-driven generator (2) is supplied to a reboiler (13) to provide heat for operation of the regenerator (10). During periods of high demand for electric power steam extraction from the boiler or turbine is discontinued, operation of the regenerator (10) is discontinued and the absorbing solution from the absorber (7) is stored in a first storage unit (15).

Abstract: An apparatus and a process for removing CO.sub.2 from a combustion exhaust gas, by effecting counterflow contact of aqueous alkanolamine solution with the combustion exhaust gas to absorb CO.sub.2 from the gas in the alkanolamine solution and effecting a further contact of the gas with either, condensate water formed by causing condensation of the gas after removal of CO.sub.2, or condensate water formed by causing condensation of the combustion exhaust gas directly after combustion of the fuel. The apparatus includes a tower (1), a first contact section (2) in the tower through which the exhaust gas flows upwardly in counterflow contact with the aqueous alkanolamine solution dispersed by a nozzle device (7) downstream of the first contact section (2), a second contact section (3) in the tower (1) downstream of the nozzle device (7) for effecting counterflow contact of reflux water from a spent absorbent liquor regenerating tower (28) with the gas after removal of CO.sub.2.