Study On Theprocess Of Treating Wasyewaterwith Mercury Inthe Productionofvinylchloride

Inthe production process of vinyl chloride,two-stage evaporation unit is a kind of technology to separate solid impurity from waste water by concentration and centrifugal.In this thesis,the technology of two-stage evaporation process is discussed,analyzed and modified.1.The principles of synthesis,compression and distillation in the production of vinyl chloride are introduced,and it is observed that the waste water with mercury is from vinyl chloride synthesis process.2.We systematically compare one-stage evaporation,two-stage evaporation,atmospheric pressure evaporation,higher pressure evaporation and lower pressure evaporation,and conclude that two-stage lower pressure evaporation technology is suitable for remove mercury from waste water.3.The process of two-stage lower pressure evaporationis modified and optimized to solve the problems of high temperature of saturated salt solution and lower efficiency of centrifugal.4.Back washing from flushing water and increasing pipe line slope are used to solve the problems of the stuck of equipment and pipe from high salinity,and these methods prolong the equipment running time and reduce the break risk of the process.5.The height of outlet pipe of vacuum pump is not enough large and there is mercury in emission gas.We prolong the drain pipe into condensing water tank and reduce the discharge of the pollutants.6.The production of by-product in two-stage evaporation is very large;thus,we use ton-bag for packaging,lower the cost and improve the working efficiency.