摘要
以能源化工行业常见产物甲醇作为溶析剂,研究了在低温条件下(≤0℃)溶析结晶回收高盐废水中氯化钠的调控方法,并结合氯化钠回收率与能耗分析优化了工艺条件。结果表明,当温度从20℃降低至-25℃时,氯化钠回收率由35.02%~52.07%提高到44.20%~62.81%,低温条件显著提高了氯化钠回收率。同时,随着温度降低,溶析结晶氯化钠晶体粒径变小,晶体形状由长方体逐渐变为正方体。当温度为-25℃,初始浓度300 g/L,搅拌速率500 r/min,搅拌时间60 min,醇水体积比2∶1时,低温溶析结晶法氯化钠回收率可达57.97%,能耗仅为三效蒸发的69%。本文研究甲醇溶析剂低温溶析工艺,为能源化工行业高浓度氯化钠废水的资源化利用提供了参考。
In this study,methanol,a common product in the energy and chemical industry,was used as the salting-out agent.The regulation of sodium chloride recovery by low-temperature solvent-out crystallization was studied.Also,suitable conditions in low-temperature solvent-out crystallization were proposed by balancing NaCl recovery rate and energy consumption.The recovery of sodium chloride increased from 35.02%~52.07%at 20℃to 44.20%~62.81%at-25℃.The results showed that the low temperature can observe the increase in NaCl recovery rate,reduction of NaCl crystal size,and the evolution from rectangular shape to square shape.Meanwhile,when the temperature at-25°C,the volume ratio of alcohol and water was 2:1,an initial concentration of 300 g/L,and stirring at 500 r/min for 60 min,the NaCl recovery rate of triple-effect evaporation crystallization can achieve 57.97%,and the energy consumption was about 69%.The low-temperature solvent-out crystallization process using methanol as the saltingout agent provides a new idea for resource utilization of high sodium chloride wastewater.
作者
方正楠
孟广源
付涛
常定明
陈鹏
张乐华
FANG Zhengnan;MENG Guangyuan;FU Tao;Chang Dingming;CHEN Peng;ZHANG Lehua(National Engineering Laboratory for Industrial Wastewater Treatment,East China University of Science and Technology;National Key Laboratory of Environmental Risk Assessment and Control for Environmental Protection Chemical Processes,East China University of Science and Technology:Shanghai 200237,China)
出处
《水处理技术》
CAS
CSCD
北大核心
2023年第11期60-65,79,共7页
Technology of Water Treatment
基金
国家重点研发计划(2019YFC0408202)
国家自然科学基金(21876050)。
关键词
低温
溶析结晶
氯化钠
甲醇
资源化
low temperature
solvent-out crystallization
sodium chloride
methanol
resources
作者简介
方正楠(1998-),女,硕士研究生,研究方向为低温水处理,电子邮件:1009852472@qq.com;通讯作者:陈鹏,博士后,电子邮件:pchen@ecust.edu.cn。
