危废中混盐的分质结晶过程研究  

Study on the Fractional Crystallization Process of Mixed Salt in Hazardous Waste

作　　者：宋莎莎 SONG Shasha(Shanghai Environmental Protection(Group)Co.,Ltd.,Shanghai 200433,China)

机构地区：[1]上海环保(集团)有限公司,上海200433

出　　处：《盐科学与化工》2025年第3期14-18,共5页Journal of Salt Science and Chemical Industry

摘　　要：危险废弃物垃圾焚烧飞灰经过循环水洗工艺脱氯处理后,飞灰水洗滤液中含有的大量无机盐影响其后续资源化利用。文章根据不同无机盐在不同温度水溶液中溶解度的差异性,通过调节机械蒸汽再压缩(MVR)蒸发结晶系统的关键性工艺参数,探讨了提高钠、钾分盐产量和纯度的路径。结果表明,MVR系统进料盐浓度在15%~20%的范围时,既可以降低加热蒸汽消耗量,减少MVR系统设备投资,又可以提高结晶盐产量;通过控制MVR系统飞灰水洗液浓缩浓度、钠钾含盐量及KCl结晶温度,可以提高分盐纯度并获得纯度>95%的NaCl结晶盐和纯度>90%的KCl结晶盐。飞灰水洗液中NaCl、KCl的分质结晶实现了危险废弃物中无机盐的高纯度回收,提高了飞灰资源化产品的附加值和废盐资源化利用率。After the dechlorination treatment by circulating washing process,the washed fly ash filtrate as hazardous waste contained a large amount of inorganic salt,which affected its subse-quent resource utilization.According to the difference of solubility in aqueous solutions of different inorganic salts at different temperatures,this article discussed the path to improve the yield and purity of sodium and potassium salts by adjusting the key process parameters of the evaporation and crystallization system in mechanical vapor recompression(MVR)process.When the salt con-centration of the MVR system feed was in the range of 15%~20%,the results showed that the con-sumption of the heating steam and the investment of MVR system equipment were reduced and the crystalline salt production was increased.By controlling the concentration of the washed fly ash fil-trate in MVR system,the content ratio of potassium and sodium salts and the crystallization tem-perature of KCl,the salt purity was improved.which reached above 95%in NaCl crystalline salt and above 90%in KCl crystalline salt.The fractional crystallization process of NaCl and KCl in the washed fly ash filtrate could not only realize the high purity recovery of inorganic salts from hazard-ous wastes,but also increase the additional value of the fly ash resource products and the utiliza-tion rate of waste salt resource.

关 键 词：危废处理 环境保护 高盐废水 分质结晶 

分 类 号：X78[环境科学与工程—环境工程]