Case | How to use oil-free screw blowers and centrifugal blowers for energy-saving transformation in the cement industry?
SCR denitrification technology, that is, selective catalytic reduction method, ammonia gas is sprayed into the high-temperature flue gas denitrification device as a denitrification agent. Under the action of the catalyst, the NOx in the flue gas is decomposed into non-toxic and pollution-free N₂ and H₂O. In the operating boiler SCR device, the denitrification rate reaches 80-90%, and the ammonia escape is below 3 mg/Nm³, which is very consistent with the further high denitrification efficiency requirements of cement plants.
① Liquid ammonia is sent from the liquid ammonia tank truck to the liquid ammonia storage tank by the unloading compressor
②After evaporating into ammonia in the evaporation tank, it enters the boiler area through the ammonia buffer tank and transportation pipeline
③After evenly mixing with air, it enters the SCR reactor through the distribution pilot valve for internal reaction. The SCR reactor is installed in front of the air preheater, and the ammonia gas is above the SCR reactor.
④Mix the smoke evenly through a special spray device
⑤After mixing, the flue gas passes through the catalyst layer in the reactor for reduction reaction.
Air compressor air soot blowing technology
When selecting the soot blowing method, in addition to the soot blowing effect, the wear effect on the catalyst must also be considered. Currently, the catalyst soot blowing methods commonly used in SCR denitration systems include sonic soot blowing, steam soot blowing and compressed air soot blowing.
Combined with the characteristics of cement kiln smoke and dust, it is difficult for sonic soot blowers to adapt to the large amount and high viscosity of cement kiln flue gas dust. In addition, the steam gas production in the cement plant is small, so it is more suitable to use compressed air to blow soot.
In recent years, with the upgrading and development of the cement industry in the field of environmental protection, emission standards have been increasingly raised. The prevention and control of air pollution and the reduction of flue gas nitrogen oxide emissions have become urgent tasks faced by cement production enterprises. SCR (Catalytic Reduction) technology has a high denitrification efficiency and can achieve ultra-low emissions of flue gas nitrogen oxides and ammonia escape under the condition of low ammonia consumption. In recent years, cement kiln flue gas SCR technology has also made certain progress, providing an effective guarantee for cement companies to achieve ultra-low emissions.
