Study Of Propylene Oxide Wastewater Pretreatment By Five-effect Evaporation Process

It will consume 1.35 1.85 tons of chlorine gas , and produce 50～150kg dichloropropane,about 2 tons waste residue of CaCl₂ and 40～80 tons Organic wastewater in producing 1 ton Propylene Oxide(PO) by Chlorohydrin process. Propylene oxide organic wastewater has characteristics with high temperature, high alkaline, high salt, high COD value and etc.Usually the propylene oxide wastewater is treated by biochemical processes. The main reason for the difficult to biochemical treatment is the high salt concentration in propylene oxide wastewater.In propylene oxide wastewater, calcium chloride is a "poison", but at the same time calcium chloride itself is an important chemical product. Therefore, before epoxy propane wastewater getting into the biochemical treatment unit,if its salinity can be reduced and calcium chloride can be recycled at the same time, we can achieve the purpose of resource and harmless of wastewater. Study on control of propylene oxide wastewater pollution based on five-effect evaporation technology is meaningful to protect the environment and promote the industry development.The purpose of this study is to control the pollution of propylene oxide wastewater based on five-effect evaporation technology and to provide references to the same enterprises.Based on the five-effect evaporation equipments of ShanDong DongDa Chemical Group,the five-effect evaporation technology and pollutant producing conditions were investigated by the method of data statistics and surveying monitor. Environmental benefit and economic benefit of the five-effect evaporation technology were analyzed by studying the resouce and energy exploitation and the pollutants reduction.Moreover,contrasting with Jordan project by using improved device, in allusion to the faults of five-effect evaporation equipment, the study puts forward the improvement measures of propylene oxide pretreatment by five-effect evaporation technology.The result of this paper has already been applied in the propylene oxide wastewater treatment project of ShanDong DongDa Chemical Group. It provides the references and the technique assistance to the control of propylene oxide pollution.