A scrubbing solution for removing contaminants, including particularly hydrogen sulfide, from a fluid. The scrubbing solution includes at least one scrubbing reagent which has a primary or secondary amine and an acid, which may be phosphoric acid. The fluid being scrubbed is passed through the scrubbing solution. The contaminants react with the scrubbing reagent securing them in the scrubbing solution. The fluid being scrubbed and the scrubbing solution are then separated. The scrubbing solution is heated and, if the scrubbing solution is under pressure, the pressure is reduced. The acid facilitates thorough removal of the contaminants, and especially the hydrogen sulfide, from the scrubbing solution. The scrubbing solution is then ready for reuse. Because the scrubbing solution is rendered substantially free of hydrogen sulfides, it can absorb other sulfide contaminants that might not otherwise be absorbed.

Controlling aerosol production during absorption in ammonia-based desulfurization. The absorption reaction temperature, the oxygen content and water content of the process gas may be controlled, and an absorption circulating liquid containing ammonium sulfite may be used for removing sulfur dioxide in flue gas, so as to control aerosol production during absorption in the ammonia-based desulfurization.

One aspect of the invention relates to a method comprising a single-stage conversion of an atmospheric pollutant, such as NO, NO.sub.2 and/or SO.sub.x in a first stream to one or more mineral acids and/or salts thereof by reacting with nonionic gas phase chlorine dioxide (ClO.sub.2.sup.0), wherein the reaction is carried out in the gas phase. Another aspect of the invention relates to a method comprising first adjusting the atmospheric pollutant concentrations in a first stream to a molar ratio of about 1:1, and then reacting with an aqueous metal hydroxide solution (MOH). Another aspect of the invention relates to an apparatus that can be used to carry out the methods disclosed herein. The methods disclosed herein are unexpectedly efficient and cost effective, and can be applied to a stream comprising high concentration and large volume of atmospheric pollutants.

This invention relates to processes for selective removal of contaminants from effluent gases. A sulfur dioxide absorption/desorption process for selective removal and recovery of sulfur dioxide from effluent gases utilizes a buffered aqueous absorption solution comprising weak inorganic or organic acids or salts thereof, to selectively absorb sulfur dioxide from the effluent gas. Absorbed sulfur dioxide is subsequently stripped to regenerate the absorption solution and produce a sulfur dioxide-enriched gas. A process for simultaneous removal of sulfur dioxide and nitrogen oxides (NO.sub.x) from effluent gases and recovery of sulfur dioxide utilizes a buffered aqueous absorption solution including a metal chelate to absorb sulfur dioxide and NO.sub.x from the gas and subsequently reducing absorbed NO.sub.x to form nitrogen. A process to control sulfate salt contaminant concentration in the absorption solution involves partial crystallization and removal of sulfate salt crystals.

A scrubber for cleaning exhaust fumes generated by internal combustion engines, in particular for reducing the concentration of the sulfur oxides SO.sub.x in exhaust fumes generated by the combustion of high sulfur content fuels, said scrubber comprising a main hollow tubular body, an inlet and an outlet for introducing and discharging said fumes into and from said main hollow tubular body, respectively, and inlet means for introducing at least partially atomized pressurized water into said main hollow body, wherein said inlet means comprise a plurality of nozzles arranged in said main hollow body and each adapted to dispense said at least partially atomized pressurized water.

The present disclosure provides a method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp. The method includes: treatment of ore waste residue, activation and domestication of silicate bacteria, preparation of pulp, removal of sulfur dioxide, and resource utilization of a desulfurization product. The present disclosure combines flue gas desulfurization with resource utilization of the ore waste residue, and improves a desulfurization efficiency of the method by the pulp and a utilization rate of ore waste residue resources through silicate bacteria. The present disclosure has a high desulfurization efficiency, simple production process, and low cost, and realizes the recycling of resources such as the ore waste residue, the sulfur dioxide, and silicon. The present disclosure has obvious economic and environmental benefits and broad prospects for use.

This invention relates to a system and method for improving sulfur recovery from a Claus unit. More specifically, this invention provides a sorption based SO.sub.2 selective crosslinked polyionic liquid system and method for treating acid gas streams and minimizing sulfur dioxide emissions therefrom.

Ammonia-based decarbonization cooling apparatus and a method therefor. The cooling apparatus may include: a first-stage cooling function zone which may use a first circulating liquid to cool a process gas to a temperature of T.sub.gas 1, a second-stage cooling function zone which may use a second circulating liquid to cool the process gas to a temperature of T.sub.gas 2, and a third-stage cooling function zone which may use a third circulating liquid to cool the process gas to a temperature of T.sub.gas 3, wherein T.sub.gas 3<T.sub.gas 2<T.sub.gas 1<T.sub.gas 0, and T.sub.gas 0 is an initial temperature of the process gas when entering the first-stage cooling function zone; a first cold source for cooling the first circulating liquid, a second cold source for cooling the second circulating liquid, and a third cold source for cooling the third circulating liquid, wherein the three cold sources may be different.

A scrubbing solution for removing contaminants, including particularly hydrogen sulfide, from a fluid. The scrubbing solution includes at least one scrubbing reagent which has a primary or secondary amine and an acid, which may be phosphoric acid. The fluid being scrubbed is passed through the scrubbing solution. The contaminants react with the scrubbing reagent securing them in the scrubbing solution. The fluid being scrubbed and the scrubbing solution are then separated. The scrubbing solution is heated and, if the scrubbing solution is under pressure, the pressure is reduced. The acid facilitates thorough removal of the contaminants, and especially the hydrogen sulfide, from the scrubbing solution. The scrubbing solution is then ready for reuse. Because the scrubbing solution is rendered substantially free of hydrogen sulfides, it can absorb other sulfide contaminants that might not otherwise be absorbed.

The present invention relates to an apparatus for reducing greenhouse gas emission in a vessel and a vessel including the same, in which an absorbent liquid recycling unit is provided in two or more stages so that an unreacted aqueous ammonium salt solution remaining in ammonia water is removed to maintain a concentration of ammonia water at a certain level, thereby increasing a recovery rate of an absorbent liquid and preventing a deterioration in greenhouse gas absorption performance. Or in which exhaust gas is cooled by a heat exchange method, thereby preventing a decrease in a concentration of an absorbent liquid, and an absorbent liquid recycling unit is provided in two or more stages so that an unreacted aqueous ammonium salt solution remaining in ammonia water is removed, thereby increasing a recovery rate of the absorbent liquid and preventing a deterioration in greenhouse gas absorption performance.