A desulfurization gas process includes water vapor, CO.sub.2 and SO.sub.x (x=2 and/or 3). In a treatment unit, the gas contacts a cooled alkaline aqueous solution having a temperature lower than an initial gas temperature, water and a carbonate of an alkali metal, to cool the gas, condense some water vapor and absorb SO.sub.x in the carbonate-containing solution, produce an SO.sub.x-depleted gas and an acidic aqueous solution including sulfate and/or sulfite ions. The SO.sub.x-depleted gas and a portion of the acidic aqueous solution can then be withdrawn from the treatment unit. Carbonate of the alkali metal can be added to remaining acidic aqueous solution to obtain a made-up alkaline aqueous solution. This solution can be cooled and reused as the cooled alkaline aqueous solution. An SO.sub.x absorbent solution includes a bleed stream from a CO.sub.2-capture process, sodium or potassium carbonate, and an acidic aqueous solution obtained from desulfurization.

A system for resource recycling of sulfur dioxide includes a charcoal reduction furnace, a high temperature dust remover, a cooling separator A, a liquid sulfur tank, a cooling separator, a tail gas absorption tower, a gas stripping tower, a hypo reactor, a centrifuge, a mother liquor tank and a thickener. And a method for resource recycling of sulfur dioxide includes the following steps: (1) preparing elemental sulfur, (2) removing dust from a process gas containing gaseous sulfur, (3) separating elemental sulfur, (4) reabsorbing residual SO.sub.2 gas, (5) purifying sulfur powder, (6) preparing a slurry of cured hypo, (7) performing liquid-solid separation, and (8) preparing an absorption slurry. According to the method, SO.sub.2 gas is reduced into liquid sulfur and sulfur powder, and sodium thiosulfate is coproduced.

An apparatus is disclosed including a desulfurization device which removes sulfur oxides contained in boiler flue gas, a spray drying device which sprays desulfurization waste water discharged from the desulfurization device and which dries the waste water by introducing a drying gas, a flue gas supplying line L.sub.13 which returns, to a main flue L.sub.11, flue gas obtained after the desulfurization waste water is evaporated and dried, an alkaline agent supplying unit which adds an alkaline agent to a desulfurization waste water line L.sub.21, and a pH meter which measures the pH in the desulfurization waste water at locations before and after the alkaline agent supplying unit in the desulfurization waste water line L.sub.21, wherein the alkaline agent is added in accordance with a measurement result of a measured pH to cause the desulfurization waste water added with the alkaline agent to have a pH fall within a predetermined pH.

A desulfurization gas process includes water vapor, CO.sub.2 and SO.sub.x (x=2 and/or 3). In a treatment unit, the gas contacts a cooled alkaline aqueous solution having a temperature lower than an initial gas temperature, water and a carbonate of an alkali metal, to cool the gas, condense some water vapor and absorb SO.sub.x in the carbonate-containing solution, produce an SO.sub.x-depleted gas and an acidic aqueous solution including sulfate and/or sulfite ions. The SO.sub.x-depleted gas and a portion of the acidic aqueous solution can then be withdrawn from the treatment unit. Carbonate of the alkali metal can be added to remaining acidic aqueous solution to obtain a made-up alkaline aqueous solution. This solution can be cooled and reused as the cooled alkaline aqueous solution. An SO.sub.x absorbent solution includes a bleed stream from a CO.sub.2-capture process, sodium or potassium carbonate, and an acidic aqueous solution obtained from desulfurization.

An ammonia-based multi-zone double-loop process for ultra-low emission of multi-pollutant. From an absorption tower inlet, the flue gas successively passes through cooling concentration crystallization, sulfur oxide absorption, water washing and purifying and dust and mist removing zones, which are separated by gas permeable liquid collecting plates, forming clean flue gas and discharged from an outlet. The cooling concentration crystallization zone, the sulfur oxide absorption zone, and the water washing and purifying zone are respectively provided with a plurality of sprayers, and respectively use a concentration liquid, an absorption liquid, and a water washing liquid as spraying liquids. The absorption, concentration and water washing liquids, after converging respectively, into absorption, concentration crystallization and water washing circulation tanks, the absorption, concentration and water washing liquids, respectively, are sprayed in a circulating manner through absorption, concentration and water washing pumps.

This disclosure provides a method for treating natural gas comprising causing at least some of a sour natural gas stream comprising hydrocarbon gas and hydrogen sulfide to contact an amine or pass through a separation system. A sweet natural gas stream comprising hydrocarbon gas and a waste gas stream comprising hydrogen sulfide are formed by contacting the sour natural gas with an amine or by passing it though a separation device. At least some of the hydrogen sulfide in the waste gas stream is oxidized, forming an exhaust gas stream comprising sulfur dioxide, which is then contacted with water or reactant and water solution or slurry to destroy or convert SO.sub.2 into a less environmentally harmful compound.

A method for simultaneously removing high-load sulfur dioxide and nitrogen oxide in waste gas, relating to the technical field of industrial waste gas purification by biological methods. According to the method, the waste gas is led into a simultaneous desulfurization and denitrification packing tower and removed, microbial floras for simultaneously removing the sulfur dioxide and the nitrogen oxide are loaded on fillers of the packing tower, and the molar concentration ratio of the sulfur dioxide to the nitrogen oxide in the waste gas is (0.76˜1.06):1.

Methods and installations for treatment of exhaust gases from marine diesel engines, in particular for reduction of the sulphur oxides (SO.sub.x) in such gases, where the reaction products resulting from the mixing of an alkaline aerosol with the exhaust gases are separated-out by means of one or more rotating centrifugal separator rotors (20) of the kind comprising a stack of narrowly spaced separation discs (22).

A method of wet-scrubbing a waste gas containing sulfur dioxide (SO.sub.2) to produce potassium thiosulfate. The wet-scrubbing facility includes multiple horizontally disposed stages where a preceding stage passes partially-scrubbed waste gas to a succeeding stage. Each stage has a scrubber mechanism to scrub waste gas with circulating fluid that progressively reduces SO.sub.2 in the waste gas before atmospheric discharge. The scrubber mechanism may optionally include a packing material to facilitate absorption of SO.sub.2 by the fluid, a sump disposed at the output of the stage to receive fluid as it drains from the packing, and a circulation pump to circulate fluid from the sump to its packing and to cascade at least a portion of the fluid back to a preceding stage. A portion of the fluid is extracted and reacted in a reaction vessel with a cation to produce potassium thiosulfate.

Proposed is a system for capturing carbon dioxide and sulfur oxide for ships that can capture carbon dioxide in flue gas using a basic alkaline mixture and use the captured carbon dioxide to capture sulfur oxides in the flue gas. The carbon dioxide and sulfur oxide capture system for ships uses sodium carbonate or sodium hydrogen carbonate prepared from the captured carbon dioxide as a desulfurization agent to capture sulfur oxides in the flue gas discharged from ships, thereby simultaneously producing carbon dioxide and sulfur oxides in one system.