Method for treating blockage of regulating valve at entrance of urea spray gun in urea ammonia production system

Abstract

The invention discloses a method for treating blockage of a regulating valve at an entrance of a spray gun in a urea ammonia production system. The method for treating the blockage of the regulating valve at the entrance urea spray gun in the urea ammonia production system comprises the following steps: comprehensively determining that blockage is caused by virtue of low urea solution flow of a urea solution regulating valve according to show value of a flow meter and experience, taking down the urea flow regulating valve (2), and washing a valve element of the urea flow regulating valve (2) with water at the temperature of 80-100 DEG C; mounting one compressed air hose between a compressed air inlet pipe (6) and a urea flow regulating valve outlet pipe (7), opening a compressed air inlet valve (4), and purging with compressed air at 0.2-0.6MPa; adjusting a position of an interface at one end of the compressed air hose from the urea flow regulating valve inlet pipe (7) to a urea flow regulating valve outlet pipe (8), and sweeping according to a previous operation step; and then repeating operation in the second step. The method for treating the blockage of the regulating valve at the entrance urea spray gun in the urea ammonia production system has the advantages that the problem that a pipeline and a valve are blocked by crystallized urea can be solved, flue gas denitrification efficiency is improved, and practicability is strong.

Description

technical field [0001] The invention belongs to the application field of urea-ammonia production technology, and in particular relates to a treatment method for clogging of an inlet regulating valve of a urea spray gun in a urea-ammonia production system. Background technique [0002] China is a country where coal is the main energy source. Coal accounts for 75% of the primary energy, of which more than 84% is utilized through combustion. Nitrogen oxides (NOx) in the exhaust gas released by coal combustion is one of the main sources of air pollution. The environmental problems and human health hazards caused by nitrogen oxides (NOx) are extremely serious. According to the China Environmental Status Bulletin, the emissions of nitrogen oxides (NOx) will continue to show a steady growth trend. If no measures are taken, China will overtake the United States to become the world's largest NOx emitter around 2020, and it is urgent to solve the huge pressure on environmental protec...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the clogging of regulating valves in the process of selective catalytic reduction denitrification (SCR) flue gas denitrification, the present invention provides a method for dealing with clogging, which can solve the problem of crystalline urea clogging pipes and valves simply and efficiently, and improve the efficiency of flue gas denitrification

Images