The Research On The Removal Of NO_x From The Flue Gas In Coke Oven

Nitrogen oxides can cause acid rain,smog,haze weather and other environmental issues.The removing and controlling have been one of the most important research focus.With the increasingly concern about environmental issues and implement of the national "coke chemical industry emission standards",the coking industry,especially for the enterprises that use the coke oven gas as heat resource have been under great pressure.Therefore it is become an important matter that reduce the emissions of nitrogen oxides,Most of the studies from domestic and overseas stay in an experience stage only,and has not been industrialized in a large scale.This paper briefly describes the hazards of NO_x and denitration technology at home and abroad.And the reason that cause the nitrogen oxides has been discussed,as well as the low temperature SCR De NO_x principles and processes.On this basement,the technology of removing NO_x at low temperature has been deeply studied on a large domestic coke oven plant Through a large number of experiments,it was found that using the low-temperature SCR catalytic De NO_x technology can meet the current coking enterprises requirements.The results show that under certain conditons catalyst can yield80% NO conversion and the concentration of NO_x can be reduced to 300 mg / m3.In this paper,a series of experiments were conducted to study catalyst activity Based on the process conditions such as gas temperature,space velocity,the amount of ammonia spray.The results show that the denitrification catalyst has good sulfur resistance in the range of 240-280 ? and space velocity of 3500-6500h-1.The denitrification efficiency is maintained above 80% by adjusting the amount of ammonia sprayed.In the normal conditions of coke oven gas,the flue gas after denitrification can meet the requirements of the new national standard.