Purification Treatment Process Of By-products Of Epichlorohydrin Production By Chlorohydrin Method

As an important basic chemical raw material and fine chemical product,epichlorohydrin is widely used in many fields.The industrial technologies for producing epichlorohydrin at home are mainly chlorohydrin method,which has some advantages in simple technology,easy operating,low investment and low quality requirements of the raw materials.However,it will produce a kind of DD mixture containing some high-added value by-products.In order to further improve the production efficiency,reduce the consumption of "three wastes" emissions and save energy,a certain company in Shandong province plans to reform the old process of 260000 tons/year production of epichlorohydrin by-products and waste.The purpose is to extract high value-added products from the waste.Not only can bring considerable economic benefits for the enterprise,but also reduce the emissions of dangerous and harmful chemicals.This paper is mainly to study the purification and treatment process of epichlorohydrin product by-products by chlorohydrin method,and optimize the heat exchange network for the process.A kind of high-value recovery process of by-products is developed by Aspen plus software,and six-column continuous distillation is used to purify and separate the by-products.In the simulation and calculation process,NRTL-RK activity coefficient model is selected as the thermodynamic model,and then the by-products purification process is simulated and calculated by Aspen plus software.The parameters such as theoretical stages number,reflux ratio,distillation rate and so on are determined by meeting the product quality standard.The best feed stage position is obtained through the sensitivity analysis.Finally,the sizing and rating of tray and pack in each distillation column are carried out.After the simulation,the heat exchange network is optimized for the separation and purification process,the heat integration of the distillation system is carried out by differential pressure technique,and reduced the energy consumption for the separation and purification process.Through the purification and separation simulation process of by-products in the DD mixture and the optimization of the heat exchange network,not only the high value-added products in the DD mixture can be successfully purified,the product quality meets the standards and recovery,the recovery and use of high-value epichlorohydrin by-products are achieved.The cost of waste treatment is reduced and the energy consumption is decreased.It has a very important practical significance for epichlorohydrin plant and has a very good guiding significance for the domestic epichlorohydrin manufacturers to re-purify and utilize epichlorohydrin by-products and effectively reduce the production energy consumption.