Abstract:

Phenol is a typical organic pollutant in coal gasification wastewater, and its treatment has received wide attention and research. Two phenol efficient degradation strains, named JHFS-1 and QHFS-1, were screened from coking wastewater and gasification wastewater by continuous domestication and plate scribing method. The effects of temperature, pH, shaking bed speed, bacterial inoculum, Cu²⁺ and Mn²⁺ on the phenol degradation were investigated by microbial degradation experiments of phenol solution, and the microbial degradation effect of gas scrubber water produced by simulated coal gasification was also investigated. Both strains were identified as Acinetobacter calcoaceticus by 16S rDNA gene sequencing and microbiological identification. The optimized degradation conditions for phenol were 30℃, pH was 6.0, shaking bed speed was 120r/min and inoculum was 13%, and the phenol degradation rate could reach 94.31% after 24h treatment. Cu²⁺ had a certain inhibitory effect on the degradation of phenol by JHFS-1, and Mn²⁺ promoted the degradation of phenol by JHFS-1 to a certain extent. The phenol degradation by microorganisms followed the hydroxylation pathway and carboxylation pathway. JHFS-1 bacteria could effectively degrade the organic pollutants in gas washing water, and the TOC degradation rate reached 58.43%.

Key words: coal gasification, water pollution, phenol, microbial degradation, degradation mechanism

摘要：

苯酚是煤炭气化废水中一种典型的有机污染物，其处理受到广泛关注和研究。本文采用连续驯化和平板划线法从焦化废水和气化废水中筛选出两种苯酚高效降解菌株，分别命名为JHFS-1和QHFS-1；通过苯酚溶液的微生物降解实验研究了温度、pH、摇床转速、细菌接种量、Cu²⁺和Mn²⁺等对苯酚降解效果的影响，还考察了模拟煤炭气化产生的煤气洗涤水的微生物净化修复效果。结果发现：经16S rDNA基因测序和微生物学鉴定，两种菌株均为醋酸钙不动杆菌（Acinetobacter calcoaceticus）；30℃、pH=6.0、摇床转速120r/min、接种量13%是苯酚的最优降解条件，经24h处理，苯酚降解率可达94.31%；Cu²⁺对JHFS-1降解苯酚有一定的抑制作用，Mn²⁺一定程度上促进JHFS-1对苯酚的降解；微生物对苯酚的降解遵从羟基化途径和羧基化途径；JHFS-1菌可有效降解煤气洗涤水中的有机污染物，其总有机碳（TOC）降解率达58.43%。

关键词: 煤炭气化, 水污染, 苯酚, 微生物降解, 降解机理