Method for oxidizing and denitrating ozone containing industrial waste gas HCl

Abstract

The invention discloses an oxidation denitration method for ozone containing HCl industrial exhaust gas, belonging to the field of environmental protection technique. The method of the invention is characterized in that ozone O3 is injected into an oxidation absorption tower where the exhaust gas with the temperature range of 40 to 200 DEG C contains the HCl, so as to oxidize nitrogen compounds such as NO, NO2, etc. in the exhaust gas as high valence nitrogen oxides NO2, N2O3, N2O5, etc. which are easy to be dissolved in water, then a complete denitration disposal process is formed by combining with a wet-method absorption technique. The oxidation denitration method has the advantages of higher denitration efficiency, saving investment, low running expense, no secondary pollution, respectively obtaining by-products to recover the resource, and improving the denitration efficiency by more than 90 percent. The oxidation denitration method can be widely applied to the denitration disposal of the exhaust gas containing various contaminations such as HCI, etc., and is especially suitable for the denitration disposal of the industrial exhaust gases containing contaminations which can lead catalyst in SCR technique to be deactivated.

Description

technical field [0001] The invention relates to the technical field of environmental protection, in particular to an HCl-containing industrial waste gas ozone oxidation denitrification method. technical background [0002] Compared with flue gas from coal-fired boilers, nitrogen-containing compounds (including NO and NO 2 etc.), because of its concentrated distribution, large emission volume, and high emission concentration, it is more harmful to the environment and human body. 2 It is one of the important air pollutants that need to be treated urgently. [0003] At present, the two technologies of selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR), which are relatively mature exhaust gas denitrification technologies, use amino reducing agents to reduce nitrogen oxides NO X Converted to harmless nitrogen gas N 2 and water vapor H 2 O. The SNCR method is carried out at a high temperature of 900-1200°C; the SCR method is carried out at a temp...

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Problems solved by technology

[0004] The main disadvantages of the SNCR method are: ① high requirements for pipelines and equipment, and high cost; ② large consumption of reducing agent and high energy consumption, unless the industrial waste gas itself has extremely high temperature; ③ low denitrification efficiency of waste gas, only 40-50%; Compared with the SNCR method, the SCR method has the advantages of high denitrification efficiency, generally up to 80% or more, and low reaction temperature, but there are still the following disadvantages in actual use: ① High requirements for pipelines and equipment, The cost is expensive and the investment is large; ②Due to the NH 3 There will be errors in the amount of metering control added, which will easily cause secondary pollution; ③ easy to leak, difficult to operate and store, and easy to form (NH 4 ) 2 SO 4 Blocking pipelines and equipment; ④ In order to avoid catalyst deactivation, there are more restrictions on other pollutants contained in exhaust gas, and the high cost of catalysts increases operating costs

But for nitrogen-containing compound concentrations up to 1×10 3 mg / m 3 -1×10 5 mg / m 3 , and the treatment technology of industrial waste gas with HCl gas of similar concentration has not been reported yet. As the public is increasingly concerned about the requirements of the environment, NO X Emission restrictions will also become increasingly strict, so finding a suitable exhaust gas denitrification method as soon as possible has become a key issue in the current environmental air treatment technology

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