【作者】 张华；

【导师】 赵东风； 刘岩；

【作者基本信息】 中国石油大学(华东) ， 环境工程（专业学位）， 2016， 硕士

【摘要】 为了缓解水资源日益紧张的现状,炼化企业实现节能减排势在必行。而含盐废水的处理效果制约着石化企业污水零排放的最终实现。本文以处理炼化企业含盐污水的低温多效蒸发实验条件为研究对象,讨论了影响MED处理效果的各个因素,并在此基础上,利用已搭建的MED实验室小试装置,考察不同的操作方案对模拟含盐废水的处理效果,并通过热力计算,得到不同系统的加热蒸汽利用率(HSU),从而确定了最优的操作方案。以三效降-降-升系统为研究对象进一步优化系统的关键参数,如进料盐度、进料流量等,最后通过模型计算分析优化了低温多效蒸发的实验条件。主要结论有:(1)通过对低温多效蒸发实验装置进行热力计算分析,可知蒸发器效数对MED性能影响显著;浓缩比(CR)对造水比(GOR)和蒸发器总换热面积影响较小;虽然末效蒸发器蒸发温度对GOR影响较小,但在效数较大时,对蒸发器总换热面积影响较大;此外,有进料预热器的MED的制水能力和经济性能显著提高。(2)为了确定最优的操作方案,以造水比(GOR)和浓缩比(CR)为评价指标,一效升膜的性能优于一效降膜;从一效至三效系统,随着效数的增加,MED系统的性能提高,三效降-降-升方案造水比为2.88,浓缩比可达4.5。此外,三效降-降-升回流方案的HSU最高,为67.78%,被确定为最优操作方案。(3)CR和GOR随效数、加热蒸汽流量的增大而增大,随进料盐度和进料流量的增大而降低。通过上述工作可获得低温多效蒸发石化企业含盐浓水的基础数据和运行规律,从而为该技术在我国石化企业真正实现工业化奠定基础。更多还原

【Abstract】 Petrochemical enterprises have become the important economy pillar in China,but more and more water are consumed and then the wastewater discharge at the same time.In order to alleviate the current situation that water resources is increasingly nervous,achieving energy conservation and emission reduction of petrochemical enterprises is imperative.High costs and heat consumption of salinity wastewater treatment also block off the achievement of "zero discharge" in petrochemical enterprises.Mathematical modes for MED were established based on the investigation of saline wastewater treatment from petrochemical enterprises at home and abroad,and analyzed the thermal performance of MED concentrating the saline wastewater from petrochemical enterprises.And on this basis,the effect of four operation schemes treating simulate saline wastewater were investigated,to use the lab-scale vertical tube MED system.Through thermodynamic calculation,the heating steam utilization(HSU)from different systems were obtained and the optimum operation scheme(three falling-falling-climbing system)was determined.The main conclusions in this paper are as follows:(1)through the thermodynamic calculation of the forward feed MED concentrated saline wastewater,The results show that performance of MED is influenced significantly by effect number;CR has slightly influences on gained output ratio(GOR)and total heat transfer areas;although evaporation temperature in last effect has slightly influences on GOR,which influences the total heat transfer areas remarkable when effect number is bigger;in addition,water capacity and economic performance of MED with the feed preheater are enhanced strikingly.(2)The results showed that climbing film system performance was better than falling film by gained output ratio(GOR)and concentration ratio(CR)were taken as evaluating indicators.The performance of MED raised with the increase of effect numbers,and GWR and CR of three falling-falling-climbing(FFC)system were 2.88 and 4.5 respectively.In addition,FFC had the maximum heating steam utilization efficiency,which was 67.78%.Ultimately,FFC was considered as optimal operation scheme.(3)Experimental results demonstrated CR and GOR raised with the increase of the effect numbers,the fresh steam flow rate and the feed water temperature,while decreased with the increase of the feed water salinity and flow rate.Through the exploration of these basic data,operation law and investment cost,we lay the foundation for the technology of multi-effect evaporation used to treat with saline wastewater of petrochemical enterprises in China to realize industrialization.更多还原