Process for synchronously removing volatile organic chemcials (VOCs), sulfides and ammonia in waste gas and recycling sulfur by chemical biological coupling method

Abstract

The invention discloses a process for synchronously removing volatile organic compounds (VOCs), sulfides and ammonia in waste gas and recycling sulfur by a chemical biological coupling method, and belongs to the field of waste gas treatment. The process comprises the following steps: firstly, introducing waste gas into an absorption tower containing a slightly alkaline solution to absorb hydrogensulfide, ammonia and a part of soluble VOCs, discharging gas subjected to removal of most of hydrogen sulfide and ammonia and a part of soluble VOCs, introducing the liquid subjected to absorption into a micro-oxygen bioreactor, separately converting the hydrogen sulfide and the ammonia into elemental sulfur and nitrogen by utilizing sulfur oxidation, ammonia oxidation, sulfur autotrophic denitrification and short-path denitrification coupling processes (sulfur oxidation bacteria, ammonia oxidation bacteria, denitrification bacteria and sulfur autotrophic denitrification bacteria), and then, introducing the obtained gas into another bioreactor to remove residual hydrogen sulfide, ammonia and VOCs. The process is reasonable, pollutant removal is not limited by concentration, the alkaline absorption solution can be recycled, repeated addition of alkali solutions is not needed, addition of a carbon source is not needed, and secondary pollution is not generated. The sulfur oxidation, ammonia oxidation, sulfur autotrophic denitrification and short-distance denitrification coupling processes (sulfur oxidation bacteria, ammonia oxidation bacteria, denitrification bacteria and sulfur autotrophic denitrification bacteria) are utilized, so that electron donors required in a denitrification process can be reduced, and operation cost is saved. Meanwhile, pollutants are converted into available elemental sulfur for recycling, so that waste recycling is realized, and the process is an ideal process for synchronously removing VOCs, sulfides and ammonia from waste gas.

Description

technical field [0001] The invention belongs to the technical field of waste gas treatment, and relates to a process for synchronously removing VOCs, sulfides and ammonia and sulfur resources from waste gas by chemical coupling biology. Background technique [0002] The problem of VOCs and odor pollution has become increasingly prominent and has become one of the main sources of PM2.5. The direct emission of exhaust gas is harmful to human health, causing serious environmental pollution and destroying the ecological balance. It is urgent to prevent and control VOCs. VOCs and odorous substances come from life and industrial production, and their components mainly include sulfur-containing compounds (sulfides, sulfides, mercaptans, etc.), (ammonia, amines, indole, etc.), oxygen-containing organic compounds (organic acids, alcohols, ketones, acids, esters, etc.), hydrocarbons (aromatic hydrocarbons, alkanes, alkenes, etc.) and halogens and their derivatives (hydrogen halides, c...

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Problems solved by technology

[0005] A process system and method patent (CN200810064858.9) for simultaneous removal of carbon, nitrogen and sulfur in wastewater invented by Wang Aijie of Harbin Institute of Technology, which converts organic matter, sulfate and ammonia nitrogen in wastewater into carbon dioxide, elemental sulfur and nitrogen, respectively. The H produced by metabolism in the gas phase 2 S and NH 3 Converted into elemental sulfur and nitrogen, however, in an anaerobic environment, high concentrations of sulfides have certain toxic effects on microorganisms, thus leading to a decline in the overall operating efficiency of denitrification desulfurization technology; toxicity inhibition brought about by high sulfide concentrations is difficult to guarantee High load operation of denitrification desulfurization process

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