A simultaneous flue gas desulfurization and denitrification process combined with chemical absorption and biotransformation and sulfur and nitrogen resources

Abstract

The invention discloses a chemical absorption combined with biological conversion synchronous flue gas desulfurization and denitrification and sulfur and nitrogen co-resource process, which uses an alkaline absorption liquid containing an oxidant to absorb SO in the flue gas in a desulfurization and denitrification absorption tower 2 and NO x Converted to sulfates, sulfites, nitrates, nitrites. Then pump the absorption liquid into the microaerobic bioreactor, and use microorganisms (sulfate-reducing bacteria) to reduce sulfate and sulfite to sulfide (S 2‑ ), which is further converted into elemental sulfur, which will absorb NO x The solution producing nitrate and nitrite is converted to ammonia. The mixed solution containing elemental sulfur and ammonia produced by the microaerobic bioreactor is processed by the ammonia and sulfur recovery system to obtain sulfur and ammonia with high content for recycling, and the alkaline solution obtained by the ammonia and sulfur recovery system is returned to the desulfurization and denitrification absorption tower Recycling. The method has reasonable process, low energy consumption, less investment and operation costs, and less secondary pollution. It can achieve the purpose of simultaneous desulfurization and denitrification of flue gas and recovery of elemental sulfur and ammonia. Resource technology.

Description

technical field [0001] The invention belongs to the technical field of waste gas purification of environmental protection engineering, and relates to a process of synchronous flue gas desulfurization and denitrification combined with sulfur and nitrogen resource utilization combined with chemical absorption and biological conversion. Background technique [0002] Sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ), mainly from natural sources such as volcanic eruptions, lightning, microbial activities, and man-made sources from man-made activities such as industry, transportation, agriculture, forestry, soil destruction, and fossil fuel combustion. x It can form photochemical smog with hydrocarbons, produce acid rain and acid fog, damage vegetation, endanger human health, and also destroy the ozone layer. At the same time, SO 2 It is also the main substance for the formation of acid rain. SO emissions from industrial sources 2 and nitrogen NO x Therefore, it is very impo...

AI Technical Summary

Problems solved by technology

However, in an anaerobic environment, denitrifying bacteria and sulfate reducing bacteria compete for a common electron donor. At the same time, the hydrogen sulfide produced by Cui needs to be further absorbed and transformed, which leads to the decline of the overall operating efficiency of denitrification and desulfurization technology; High-load and high-efficiency operation of nitrification desulfurization process

[0006] In the process of oxidant wet flue gas denitrification, nitrogen oxides are absorbed by the absorption liquid containing oxidant and oxidized to nitrate, and the direct discharge of denitrification wastewater containing nitrate may cause water pollution.

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