Design And Control Of Reactive Distillation For Hydrolysis Of Methyl Glycolate To Ethanol Acid

Glycolic acid is an important chemical product which was used in daily chemical,medical treatment and coating fields.In order to solve these problems,such as complex production process of glycolic acid,high energy consumption and non-manipulative process,the hydrolysis technology of glycolic acid methyl ester(MG)system of continuous reaction distillation for ethanol acid(GA)was researched,then the reaction distillation column was designed and controlled using Aspen simulation.The kinetic and thermodynamic properties were studied for reaction distillation process.The equipment stability of 5L kettle autocatalytic reaction process was investigated.The results showed that the device could work for 45h stably during the process.The total conversion of MG reached 99.95%.The Aspen simulation value had good agreement with experimental value,which demonstrated the reliability of autocatalytic reaction distillation model.And it turned out that this technology could meet the needs of MG hydrolysis process in the appropriate operating conditions and reaction distillation equipment.In the economic design of reaction distillation column for ten thousand tons of MG,the total annual cost(TAC)was adopted as the economic objectives.The iterative optimization method was used in calculating rectifying tray number NR,total tray number Nt,feed position Nfeed.The results showed that the TAC decreased by 6.2%and reflected the economy of reaction distillation technology.The two-point temperature control and temperature-concentration cascade control were proposed for the dynamic simulation of reaction distillation process.There were disturbance analysis of feed flow and component.The results indicated that the two plans were effective to control for reaction distillation.The response of cascade control was faster and better to maintain the quality of the products.So the scheme was used to reduce the change of quality caused by disturbance and the fluctuations of the parameters inside the tower to improve the economic benefits of enterprises.