Abstract: A steam supply system that can reheat CO2 absorbing liquid without lowering performance of a reboiler by decompressing a condensed water drum is provided. This system includes a reboiler that raises the temperature of absorbing liquid contacted with exhaust gas discharged from a boiler to absorb CO2 in the exhaust gas and heated to eliminate CO2. The reboiler includes a heat exchanger tube to which steam for heating is supplied and a condensed water drum that recovers condensed water of the steam introduced from the heat exchanger tube as steam drain, and the condensed water drum is provided with decompression unit that lowers pressure in the condensed water drum.

Abstract: Apparatuses, systems, and methods for removing acid gases from a gas stream are provided. Gas streams include waste gas streams or natural gas streams. The methods include obtaining a hypochlorite and a carbonate or bicarbonate in an aqueous mixture, and mixing the aqueous mixture with the gas stream to produce sulfates or nitrates from sulfur-based and nitrogen-based acidic gases. Some embodiments of the present disclosure are directed to produce the carbonate and/or bicarbonate scrubbing reagent from CO2 in the gas stream. Still others are disclosed.

Abstract: A wet process for the desulphurization of hydrogen sulphide laden gas, including absorption of hydrogen sulphide in aqueous medium by a carbonate salt, oxidation of hydrogenosulphide into elemental sulphur in the presence of a vanadium compound with concomitant reduction of said vanadium compound, re-oxidation of said vanadium compound in the presence of the couple quinone-2-sulfonic acid/hydroquinone-2-sulfonic acid or quinone-2-phosphoric acid/hydroquinone-2-phosphoric acid or a salt thereof, the substituted hydroquinone catalyst being re-oxidized in the presence of oxygen.

Abstract: The present invention relates to a new process for removal of carbon dioxide from a feed gas, wherein the feed gas is fed to and concentrated in a stripper column (A) before condensation of the gaseous carbon dioxide. The present invention also relates to different uses of the removed carbon dioxide and to a plant for removal of carbon dioxide from the feed gas.

Abstract: The invention provides phosphors composed of Eu(1-x)MaxMg(1-y)MbyAl(10-z)MczO17, wherein Ma is Yb, SN, Pb, Ce, Tb, Dy, Pr, Ca, Sr, Ba, or combinations thereof, and 0?x?0.9; Mb is Mn, Zn, or combinations thereof, and 0<y?0.7; Mc is Ga, In, B, or combinations thereof, and 0?z?5. These phosphors emit visible light under the excitation of ultraviolet light or blue light, and these phosphors may be further collocated with different color phosphors to provide a white light illumination device. Alternatively, the phosphors of the invention can improve the efficient utilization of the light in solar cell.

Abstract: The gaseous effluent to be treated is contacted in column C1 with an absorbent solution selected for its property of forming two separable phases when it is heated. The regenerated absorbent solution is separated into two phases in drum B1; a fraction rich in water and a fraction rich in reactive compounds. Separation allows to optimize the operations performed on the regenerated absorbent solution. On the one hand, separation allows to carry out vaporization, through reboiler R1, of a fraction of the absorbent solution, preferably containing a limited reactive compound concentration in relation to the absorbent solution, thus limiting their degradation. On the other hand, separation of the phases allows to reduce the amount of solution to be treated in order to remove the non-regeneratable salts and thus to reduce the costs linked with their elimination. Finally, separation allows to eliminate the degradation products by carrying out a specific and suitable purification for each phase.

Abstract: A fluidized bed reactor device for sequestering flue gas CO2 from a flue gas source is provided. The fluidized bed reactor device comprises an operating portion having a first end and a second end. A flue gas inlet is formed at the first end of the operating portion with the flue gas inlet receiving flue gas from the flue gas source. A flue gas outlet formed at the second end of the operating portion. A distributor plate is mounted within the operating portion adjacent the first end of the operating portion. A volume of fly ash is encased within the operating portion between the second end and the distributor plate with the flue gas traveling through the distributor plate and the fly ash creating reacted flue gas wherein the reacted flue gas exits the operating portion through the flue gas outlet.

Abstract: A method of recovering carbon dioxide from a stream of flue gases, includes: contacting the stream at a gas pressure above atmospheric pressure with an aqueous solvent system, containing ammonium, carbonate and bicarbonate ions, at a temperature above 10° C. to effect absorption of CO2 from the stream, and separating the solvent containing the absorbed CO2 (as carbonate, bicarbonate and CO2(aq)) from the stream of CO2-leaner flue gases to form a CO2 and/or bicarbonate-rich solvent stream. In a second aspect, the CO2-leaner flue gases are cooled by contact with water that dissolves ammonia therefrom, and recycling said dissolved ammonia back to said solvent system. Apparatus is also disclosed.

Abstract: A method of manufacturing a synthesis gas containing hydrogen and carbon monoxide comprises steps of removing only hydrogen sulfide from a natural gas containing hydrogen sulfide and carbon dioxide by permitting the natural gas to pass through a hydrogen sulfide-removing device filled with a hydrogen sulfide absorbent, adding carbon dioxide and steam to the natural gas which the hydrogen sulfide has been removed to prepare a mixed gas, and feeding the mixed gas into a reaction tube of a reformer, thereby permitting mainly a steam reforming reaction to take place in the mixed gas. This method enables hydrogen sulfide in natural gas to be removed while permitting the carbon dioxide of natural gas to be effectively utilized, thereby reducing the quantity of carbon dioxide to be added to the natural gas to be transferred to the reformer.

Abstract: Process for the removal of carbon dioxide (CO2) and minor sulfur compounds—mainly hydrogen sulfide (H2S)—from a sour gas mixture, such as natural gas, iron ore reduction gas, etc. The process uses a continuous absorption process with an alkaline aqueous liquid mixture containing 15-40% by weight of equivalent K2CO3 and is conducted at a temperature of about 150 degrees F. to 300 degrees F. The H2S is removed from the sour gas as elemental sulfur. A high concentration (at least 10 to 1 molar ratio) of penta-valent vanadium (V+5) to H2S is maintained at a high temperature (150 to 300 degrees F.) to help minimize thiosulfate formation, raise the absorption temperature, and increase the speed of conversion of H2S to elemental sulfur. CO2 is stripped from the aqueous alkaline solution and vented directly into the atmosphere since the sulfur that usually contaminates the CO2 was removed earlier in the process as elemental sulfur.

Abstract: A process to remove carbon dioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbon dioxide reacts with the metal compound to generate carbonate.

Abstract: An aqueous stream such as pulp mill condensate containing one or more sulfur compounds is treated by (a) reacting an aqueous feed stream containing TRS contaminant selected from the group consisting of hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, and mixtures thereof, with ozone to produce a first liquid product stream and a first gaseous product stream, wherein the total amount of said one or more contaminants in said first liquid product stream is less than 1% of the amount thereof in said feed stream, and wherein said first gaseous product stream contains ozone and one or more of said contaminants; and (b) treating said first gaseous product stream with an alkaline aqueous stream to remove essentially all of said one or more contaminants from said first gaseous product stream. Preferably, a second gaseous stream produced in step (b) and containing ozone is reacted with an aqueous stream containing one or more of said contaminants, to consume all the ozone in said stream.

Abstract: A stable amorphous rare earth oxide, such as Y.sub.2 O.sub.3, including a stabilizer, such as carbon, silicon carbide, or hafnium oxide. The stable amorphous rare earth oxide can be used in a dielectric layer in a magneto-optical recording medium.

Abstract: An apparatus is disclosed for removal of contaminate(s) from a gas stream in an oil or gas refinery using an absorber-regenerator process wherein a portion of the contaminate rich overhead gas from the regenerator is utilized to increase the partial pressure of the contaminate at the absorber so as to enhance selective absorption of the contaminate(s).

Abstract: This invention relates to an alkaline scrubber for condensate stripper off-gases. In particular, this invention relates a process for selectively removing hydrogen sulfide and methyl mercaptan from a gas stream containing these compounds and methanol. Such gas streams are commonly generated during pulp and paper production.

Abstract: A hydrocarbon stream is washed with caustic solution to reactively remove hydrogen sulfide and produce a spent caustic solution containing sulfide reaction products. The spent caustic solution is stripped with concentrated carbon dioxide to reactively remove the sulfides and produce an overhead hydrogen sulfide stream and a bicarbonate-containing bottoms stream. The hydrogen sulfide stream can be converted to elemental sulfur in a Claus unit or to sulfuric acid in a sulfuric acid plant. The bicarbonate solution can be washed with liquid hydrocarbon to remove mercaptans and phenols in further preparation for disposal.

Abstract: To a gas which contains H.sub.2 S and water vapor and which is to be desulfurized oxygen is added at such a rate that the gas contains 1 to 20 moles O.sub.2 per mole of H.sub.2 S. At a temperature in the range of 50.degree. to 180.degree. C. the gas is contacted with activated carbon, which is thus laden with elemental sulfur and with at least 3% by weight sulfuric acid. In a suitable processing, the gas which is to be desulfurized and contains at least 1000 ppm H.sub.2 S+SO.sub.2 is initially passed at a temperature from 100.degree. to 180.degree. C. through a catalytic prepurifier, in which elemental sulfur is adsorbed on a high-metal-oxide catalyst, oxygen is admixed to the gas coming from the prepurifier and the gas at a temperature of 50.degree. to 180.degree. is contacted with the activated carbon for a final desulfurization.

Abstract: A process for oxidizing a metal from a lower valence state to a higher valence state comprises contacting the metal, usually contained in a solution, with a sufficient amount of an oxygen-containing gas to provide at least about 300% excess of stoichiometric oxygen with respect to the metal at the lower valence state. The metals are preferably used as chelated solutions thereof. Some of the representative metals are iron, copper, manganese, lead or mercury.

Abstract: An improved system for recovering CO.sub.2 from flue gases containing SO.sub.2 at low CO.sub.2 partial pressure. The system includes the use of K.sub.2 CO.sub.3 as the solvent, regeneration of the solvent, and removal of SO.sub.2 and SO.sub.4.

Abstract: An improved method for removing malodorous sulfur compounds from flue gases generated in kraft or sodium sulfite pulping operations and the like by the absorption process using green liquor, an aqueous solution containing sodium sulfide and sodium carbonate. The malodorous gas compounds, including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide are preferentially absorbed by the sodium sulfide forming sodium hydrosulfide and methanol. Any sulfur dioxide in the gas is absorbed and neutralized by sodium carbonate. In this method carbon dioxide absorption is minimized and the formation of sodium bicarbonate is limited. Sodium bicarbonate formation is minimized in order to avoid its reaction with sodium hydrosulfide which would then release undesirable hydrogen sulfide during absorption, as well as to forestall the need to increase chemical and lime kiln capacity requirements when the green liquor returned to the kraft recovery process contains excess amounts of sodium bicarbonate.

Abstract: Regenerative process for the purification of a non-reacting industrial gas stream by removal of trace amounts of carbon dioxide therefrom, comprising contacting said gas stream with non-aqueous liquid solution of at least one member selected from the group consisting of: (a) hydroxides and weak acid salts of sodium, potassium, and lithium and (b) specific liquid aliphatic polyhydric alcohol; separating the purified industrial gas from the reaction products of said contacting step including said solution; increasing said reaction products stream to an elevated temperature up to 200.degree. C.; reducing the partial pressure of carbon dioxide in the vapor phase above said reaction product stream; separating carbon dioxide from said reaction product stream; and recycling the treated reaction product stream to said liquid body of said solution for contacting a further quantity of said industrial gas stream.

Abstract: The present invention relates to an alkaline salt promoter system which includes N-secondary butyl glycine and its use in acid gas scrubbing processes.

Abstract: Decarbonation of gases with solutions of alkali metal carbonates and with alkanolamine solutions is improved by exploiting the heat of the vapors exiting the head of the alkanolamine solution regeneration column and also the heat of fluids condensed at the head of the regeneration column for the alkali metal carbonate solution. A very favorable heat balance is achieved and considerable power savings.

Abstract: In a process of selectively desulfurizing gases which contain hydrogen sulfide and carbon dioxide comprising scrubbing the gases with an aqueous potassium carbonate solution under superatmospheric pressure and at temperatures of about 100.degree. C., regenerating the laden scrubbing solution and recycling the regenerated scrubbing solution, the improvement wherein the gases to be purified are scrubbed with an aqueous potassium carbonate solution so as to maintain a mass ratio of 1.0 to 3.0 vals (gram equivalents) of alkali in the solution per mole of CO.sub.2 and H.sub.2 S in the gases to be purified, the laden scrubbing liquor is subsequently regenerated by being stripped with a gas in which a CO.sub.2 partial pressure above 0.2 bar is maintained, and the so regenerated scrubbing solution is recycled.

Abstract: A process for selectively absorbing H.sub.2 S from gas mixtures which contain CO.sub.2 and H.sub.2 S in a molar ratio of 4:1 or greater and in which the gas flow rate varies substantially. Alkali metal carbonate solutions are used with absorption under pressure and at an elevated temperature and desorption by steam stripping at about atmospheric pressure. The degree of selectivity of H.sub.2 S removal is maintained constant despite substantial variations in the gas flow rate by maintaining a constant stripping steam/gas ratio selected to provide the desired partial pressure of H.sub.2 S in the purified gas and by adjusting the solution/gas ratio to a value in the vicinity of that at which the partial pressure of H.sub.2 S in the purified gas remains at said selected value while the difference between the partial pressures of CO.sub.2 and H.sub.2 S in the purified gas reaches a maximum value, and by then maintaining such solution/gas ratio as the gas flow rate varies.

Abstract: A process for the selective removal of hydrogen sulfide from a gas containing hydrogen sulfide and carbon dioxide wherein said gas is contacted at superatmospheric pressure with an alkali metal carbonate solution, the resultant solution which contains hydrosulfide and bicarbonate is subjected to pressure reduction, the total alkali metal bicarbonate content of the resultant solution is adjusted so that it is at least 55% of the total alkali content of the solution and the said solution is then stripped and recycled to the hydrogen sulfide absorption step.

Abstract: A process for removing gaseous impurities such as CO.sub.2 and/or H.sub.2 S from a gaseous mixture obtained by reacting combustible substances with steam, said steam being produced in boilers fed with water previously purified in degassing columns. The gaseous impurities are removed by means of an absorbent solution and the latter is regenerated in a regeneration column by stripping with steam. The stripping steam necessary for the degassing is delivered, at a pressure at least equal to that in the regeneration column, to the degassing columns and then to the regeneration column. The boiler feed water to be purified is previously heated, by supply of residual heats, to a temperature in the vicinity of the boiling temperature of the absorbent solution in the regeneration column.

Abstract: Gas purification processes for removing hydrogen sulphide (H.sub.2 S) from a foul gas stream, such as coal carbonization gases, involving a circulating liquid reagent in which the H.sub.2 S is absorbed and converted to sulphur which is recovered and the reagent regenerated and recycled exhibit progressive deterioration of the circulating reagent due to contamination by process by-products. The invention provides a method of decontaminating such a circulating reagent by subjecting a bled-off sidestream to high temperature hydrolysis, so producing gaseous products recyclable to the foul gas stream. Solid products may also be produced which may be recycled to the reagent, perhaps after high-temperature reduction.