Lactic acid is widely used in the food,chemical and pharmaceutical industries,and there is an increasing demand for lactic acid as the raw material of poly lactic acid (PLA),which is a biodegradable polymer.Lactic acid production has been changing over from production by synthesis to production by fermentation,since the fermentation process is more environmental friendly and economic.However,fermentation method generates excess water and impurities with high boilers.The presence of high boilers and non-volatile nature of lactic acid makes the purification of lactic acid very difficult job.Reactive distillation can be a method to overcome the difficulties.Lactic acid is converted into methyl lactate,which is easily purified by distillation,through esterification reaction.Methyl lactate is converted to lactic acid by hydrolysis reaction.We introduce a new highly integrated process,reactive dividing wall column.The reactive dividing wall column combines reactive distillation and dividing wall column.We compare capital costs and energy consumptions between the proposed and conventional process and examine the effects of major process variables on the colunm performances.We also propose a new control structure for the proposed reactive dividing wall column.The proposed control stncture can keep the recovery yield at desired value in the face of feed flow and composition disturbance.