Cause and countermeasure of secondary salt increase in desulfurization system after indirect cooling renovation of semi-water gas
The semi-water gas produced by the traditional atmospheric pressure intermittent gasifier was cooled directly by the circulating water,which caused harmful substances escaping into the air.As per requirements of the national environmental protection policy,Shanxi Jinfeng Coal Chemical Co.,Ltd.had transformed direct gas cooling into indirect cooling.After the renovation,the problem of harmful gas escaping from circulating water could be solved,but the hydrogen cyanide in the gas was carried to the primary desulfurization section,forming the sodium thiocyanate,resulting in blockage of the desulfurization tower and excessive material consumption.The formation mechanism of thiocyanate was introduced,with key analysis on two modification schemes:desulfurization solution salt separation technology and NHD solution desulfurization technology.
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NSTL
万方数据
维普
