Treatment Of High Salinity Organic Wastewater Via Electrodialysis

The shortage of water resources is an important problem in our country,which not only restricts the development of industry and agriculture and affects the human’s health.The treatment of high salinity wastewater is always one of the difficult problems in wastewater treatment.In addition,it is more difficult to deal with the high salinity wastewater containing acid(or alkali)and organics.Each of the physical,chemical and biochemical methods has its own advantages in treating this wastewater.The integrated membrane technology combines the advantages of both physical and chemical methods,and can recover some materials in the wastewater and recycle this water.This method is relatively green and environment friendly,more importantly,sometimes greatly reduce the production costs.The 3-chloroallyl alcohol mixed solution to be treated in this study contains a large amount of sodium chloride and sodium bicarbonate.The main purpose of this work is to recover the 3-chloroallyl alcohol and/or recycle other matters.Since the electrodialysis technology can remove the salt without the migration of un-ionized organic matters,which can realize the separation of organic matter and salt in the solution,the electrodialysis process was proposed to treat this high salinity wastewater with 3-chloroallyl alcohol.In this paper,we find out the problems of low recovery rate of 3-chloroallyl alcohol and high water permeability.These problems included three parts: the first part was the exploration of the overall operating conditions,including the membrane type,volume ration,material concentration,current density,etc..In the second part,water permeability was investigated.The effect factors included m salt concentration and current density,and the salt concentration was found to be the key factor.The third part was performed to explore the recovery of 3-chloroallyl alcohol on the basis of the investigations of the above two parts.At last,the technique of electrodialysis was optimized.The optimization result showed that the final recovery rate of 3-chloroallyl alcohol achieved 95%.