摘要
聚氨酯泡沫对微生物、水环境友好,且成本相对低廉,来源广泛,适用于大规模的应用,是一种国内外普遍应用的微生物固定化载体材料。将优势菌株使用聚乙烯醇(PVA)固定化处理后,模拟大庆地区浅层地下水环境,耦合聚氨酯泡沫分析BTEX降解反应的量效关系,得到最佳工艺参数。初始苯系物质量浓度为400 mg·L^(-1),pH值为6.5,最适温度为10℃,Fe离子质量浓度为16 mg·L^(-1)、Mn离子质量浓度为12 mg·L^(-1),最适接种量为3块,所占体积比为40.5%,该固定化体系培养48h后,对苯系物的降解率达91.86%。模拟低温地下水苯系物的去除实验表明,在苯系物初始质量浓度为400 mg·L^(-1)的模拟水样中,48 h苯系物的去除率最高,达98.92%,苯系物最终质量浓度为4.19 mg·L^(-1)。固定化体系前期聚氨酯泡沫的吸附作用对苯系物的去除贡献较大,吸附达到饱和时,生物降解才是更为重要的去除机理。通过扫描电镜观察载体内部的微生物,聚氨酯泡沫上纵横交错分布的孔隙为菌胶团的生长提供了支撑骨架;并利用分光光度计测定不同苯系物初始质量浓度的载体内的生物量的变化,苯系物质量浓度为400 mg·L^(-1)时,聚氨酯泡沫载体附着生物量可达6 734.41μg·g-1。在不固定条件下的菌液中蛋白质质量浓度为71.48μg·mL^(-1),固定化菌能够较好适应低温条件下地下水中苯系物的污染环境,生物载体填料为工业化应用提供了基础。
Polyurethane foam is a kind of microbial immobilized carrier material widely used at home and abroad, which is friendly to microorganism and water environment, relatively low cost, wide source and suitable for large-scale application. After the dominant strain was immobilized with polyvinyl alcohol(PVA), the shallow groundwater environment in Daqing area was simulated, and the dose-effect relationship of BTEX degradation reaction was analyzed with coupled polyurethane foam to obtain the best process parameters. The initial concentration of benzene series was 400 mg·L^(-1), the pH value was 6.5, the optimal temperature was 10 ℃, the Fe ion mass concentration was 16 mg·L^(-1), the Mn ion concentration was 12 mg·L^(-1), the optimal inoculant amount was 3 pieces, the volume ratio was 40.5%, the degradation rate of benzene series reached 91.86% after 48 h culture of the immobilized system. The removal experiment of benzene series in simulated low-temperature groundwater showed that the removal rate of benzene series at 48 h was 98.92% and the final concentration of benzene series was 4.19 mg·L^(-1) among the simulated water samples with the initial concentration of benzene series at 400 mg·L^(-1).In the early stage of the immobilized system, the adsorption of polyurethane foam contributed a lot to the removal of benzene series. When the adsorption reached saturation, biodegradation was the more important removal mechanism. The microbe inside the carrier was observed by SCANNING electron microscope(SEM). The pores in the polyurethane foam provided a supporting framework for the growth of micelles. The biomass in the carrier with different initial concentration of benzene series was measured by spectrophotometer. When the mass concentration of benzene series was 400 mg·L^(-1), the attached biomass of polyurethane foam carrier could reach 6 734.41μg·g-1.The protein content in the fluid under the unfixed condition was 71.48 g·mL^(-1). The immobilized bacteria could adapt to the environment polluted by benzenes in the groundwater under the low temperature condition, and the biological carrier filler provided the basis for the industrial application.
作者
张雷
丁瑞东
陈琦楠
苗月
ZHANG Lei;DING Rui-dong;CHEN Qi-nan;MIAO Yue(School of Earth Sciences,Northeast Petroleum University,Daqing 163000,China;Test Team of No.1 Oil Production Plant of Daqing Oilfield Co.,Ltd.,Daqing 163000,China;Test Team of No.6 Oil Production Plant of Daqing Oilfield Co.,Ltd.,Daqing 163000,China)
出处
《当代化工》
CAS
2021年第9期2017-2023,共7页
Contemporary Chemical Industry
基金
国家自然科学基金,季节性冻土条件下包气带-地下水间BTEX纵向迁移转化机理研究(项目编号:41877489)
黑龙江省优秀青年基金,GOF-工程菌耦合新型PRB修复BTEX污染地下水研究(项目编号:JJ2020YX0502)。
关键词
固定化
地下水
苯系物
微生物降解
Immobilized
Groundwater
Benzene series
Microbial degradation
作者简介
张雷(1982-),男,辽宁省锦州市人,副教授,博士,2015年毕业于哈尔滨工业大学环境科学与工程专业,研究方向:石油烃类有机污染治理技术。E-mail:zhlei162@126.com;通信作者:丁瑞东(1995-),男,硕士研究生,研究方向:环境地球化学。E-mail:2023144653@qq.com。
