Research Of Electronic Grade Silicon Tetrachloride Distillation Simulation,Energy Saving And Control Scheme

Electronic grade silicon tetrachloride is the main raw material for photovoltaic industry and electronic industry.Domestic demand for high purity silicon tetrachloride is extremely huge.In this paper,by analyzing the composition and properties of silicon tetrachloride,we determine the four towers distillation process.The use of chemical process simulation software for the steady state simulation of the tower optimizes operation parameters.Based on the distillation process energy consumption and economic benefit analysis,energy-saving scheme selects heat pump distillation,making system energy allocate rationally.Then to dynamic simulation of the tower,determine appropriate control scheme.Finally,using the Aspen Dynamics for dynamic simulation,appropriate control scheme is determined.This paper deals with the main physical system of silicon tetrachloride is silicon tetrachloride(STC)-trichlorosilane(TCS).Firstly,we use STC-TCS vapor-liquid equilibrium experiment data which obtained from related references to carry out thermodynamic consistency test and verify the reliability of Data.On the basis of experimental Data,we use Aspen Plus built-in Data Regression module to fit Regression binary interaction parameters,and PENG-ROB property method with smallest deviation can simulate calculation on subsequent processes.Using Aspen Plus strict algorithm for steady state simulation and determined by sensitivity analysis and orthogonal test to optimize the operation parameters of the towers,after optimization,each tower stage number N,feed position NF,reflux ratio R,the yield ratio respectively:T1 is 61,5,6.1,0.127(D/F);T2 is 56,33,3.9,0.0035(B/F);T3 is 51,5,11.3,0.1(D/F);T4 is 39,32,10.8,10.8(B/F).The optimized products conform to the requirements of the industry.On the basis of the steady state simulation in convergence and analysis of heat pump distillation energy saving technology,adjusting the feed temperature to 54.5 ?.Contrast the energy-saving process with original process,the new process saved energy of 94.53%,cooling medium of 2.7388 million tons/year,heating medium of 45290 tons/year.In order to improve distillation operation stability,we select appropriate dynamic model and control scheme for each tower by using Aspen Dynamics,Firstly,we determine the sensitive plates of rectifying section and stripping section.According to the dynamic response of the feed quantity and feed component disturbances,the dynamic responses of the two schemes were compared and selected:T1 of material balance control scheme;T2,T3,T4 rectifying section respectively of material balance control scheme,D/F constant ratio control scheme,R/F constant ratio control scheme,and T2,T3,T4 stripping section all of energy balance control scheme.