摘要
高效反渗透(high efficiency reverse osmosis,HERO)工艺是工业废水零排放系统浓盐水浓缩减量的关键,其运行效果显著影响浓盐水蒸发结晶的效能,直接决定系统运行的稳定性和运行成本。针对我国北方某煤化工厂废水零排放系统中的HERO工艺运行效果及膜污染特征进行了分析,以明确HERO系统的关键问题。结果表明:澄清池和弱酸阳床可有效实现废水中硬度离子的去除,其他离子与污染物主要由反渗透(RO)单元去除。废水中溶解性有机物(DOM)主要以腐殖酸类物质和微生物代谢产物(SMP)类物质为主,且腐殖酸类物质主要为微生物源。预处理阶段对SiO_(2)无针对性控制措施,混凝除硅效果较差(去除率29.43%),HERO进水SiO_(2)质量浓度较高,导致RO膜出现显著的硅复合污染,其中1段第1根膜污染物以硅和有机物耦合物、微生物及其代谢产物为主,二段最后1根膜表面出现大量颗粒状硅垢。因此,针对此HERO工艺,需进一步强化SiO2的去除并实现其有效清洗,是缓解膜污染并提升系统稳定性的重要措施。
The concentration and reduction of concentrated brine by high efficiency reverse osmosis(HERO)process is the key for the zero liquid discharge wastewater system.Its operation effect significantly affects the efficiency of the following evaporation and crystallization,and directly determined the stability and cost of the system operation.In this study,the operation effect and membrane fouling characteristics of a HERO process for the zero liquid discharge coal chemical wastewater treatment system in North China was analyzed to disclose the key issue in HERO.Calcium and magnesium can be efficiently removed in the clarifying ponds and cation exchange system,while other ions and pollutants are mainly removed in RO.The dissolved organic matters are mainly microbial sourced humic substance and soluble microbial products,and humic substance is the main microbal source.The pretreatment stage has not targeted measure for SiO_(2) control,and the removal efficiency of silica(SiO_(2)) is poor(29.43%) for coagulation,thus the concentration is high in the HERO process,resulting in severe silica combined fouling.The silica-organics,microorganisms and their metabolites are the main foulants in the 1st-stage RO,while silica scaling appear in the 2nd-stage RO due to the high concentration factor.Therefore,further strengthening SiO_(2) removal and its cleaning efficiency during chemical cleaning are key measures to alleviate membrane fouling and improve the operation stability.
作者
王燕翔
郑利兵
钟慧
段宁鑫
胡大洲
魏源送
李清雪
WANG Yanxiang;ZHENG Libing;ZHONG Hui;DUAN Ningxin;HU Dazhou;WEI Yuansong;LI Qingxue(School of Energy and Environmental Engineering,Hebei University of Engineering,Handan 056038,China;Laboratory of Water Pollution Control Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;State Key Joint Laboratory of Environment Simulation and Pollution Control,Research Center for EcoEnvironmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2024年第1期101-109,共9页
Chinese Journal of Environmental Engineering
基金
国家重点研发计划(2021YFC3201403)
国家自然科学基金面上资助项目(52270081)。
关键词
煤化工废水
高效反渗透
膜污染
有机物
二氧化硅
coal chemical wastewater
high efficiency reverse osmosis
membrane fouling
dissolved organic matter
Silica
