Desulfurization and denitrification device and method for sintering flue gas

Abstract

The invention belongs to the environment protection field in metallurgical industry, and relates to a desulfurization and denitrification device and method for sintering flue gas. The sintering flue gas generated by a sintering machine is firstly treated through dust removal, the sintering flue gas obtained after dust removal enters a desulfurization reactor containing activated coke for desulfurization treatment, the desulfurized sintering flue gas passes through a denitrification reactor containing a low-temperature catalyst for denitrification, and finally the flue gas passes through an induced draft fan to be directly exhausted from a chimney. Accordingly, the activated coke can be used for regenerating activated coke and producing a sulfuric acid product through an activated coke desorption tower and a sulfuric acid preparation system after adsorbing SO2, and not only is it guaranteed that the activated coke can be reused, but also the sulfuric acid by-product is generated; a porous low-temperature denitrification catalyst is adopted as the low-temperature catalyst, and the service life is long. After the sintering fuel gas is treated through the desulfurization and denitrification technology, the contents of SO2, NOx, dust and the like in the fuel gas can all reach the discharge standard, therefore, the device can meet the discharge standard, the whole technological process is simple, the desulfurization and denitrification effect is good, and the great application value is achieved.

Description

technical field [0001] The invention belongs to the field of environmental protection in the metallurgical industry, in particular to a sintering flue gas desulfurization and denitrification device and method. Background technique [0002] China's iron and steel enterprises are mainly based on the long process of "sintering-blast furnace-converter-continuous casting" smelting production. The sintering process is the raw material supply process for blast furnace ironmaking. Almost all large-scale iron and steel enterprises have sintering processes. The largest iron and steel enterprises The pollution source comes from the sintering process, and the average SO in the sintering flue gas produced by the sintering process 2 Concentration at 1000mg / Nm 3 Above, NO x Concentration at 400mg / Nm 3 above. In the latest flue gas emission standard for sintering machines promulgated in 2012, the flue gas emission standard for new sintering machines is SO 2 Concentration at 200mg / Nm 3...

AI Technical Summary

Problems solved by technology

At present, it is unrealistic to directly denitrify the flue gas after limestone-gypsum desulfurization by low-temperature catalysts, because the moisture content in flue gas after traditional limestone-gypsum wet desulfurization is very high, and the water volume of flue gas generally discharged The content is more than 7%, which will seriously affect the use effect of the catalyst. Therefore, the traditional limestone-gypsum desulfurization process combined with low-temperature catalytic denitrification is not feasible.

[0003] Although currently only TISCO in my country adopts simultaneous desulfurization and denitrification of activated coke, the problem with this simultaneous desulfurization and denitrification is that the desulfurization efficiency of activated coke will be affected after the ammonia gas is introduced into the flue gas, resulting in a large amount of activated coke , the overall equipment investment and operating costs are relatively high, therefore, this is also the problem faced by simultaneous desulfurization and denitrification of activated coke

[0004] In short, on the basis of the existing sintering flue gas wet desulfurization process, flue gas denitrification cannot be directly performed, and the method of simultaneous desulfurization and denitrification with activated coke faces cost problems. Therefore, it is necessary to find a suitable desulfurization and denitrification of sintering flue gas new methods and processes

Images