State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730070, China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
Sci Total Environ. 2020 Jun 25;723:137995. doi: 10.1016/j.scitotenv.2020.137995. Epub 2020 Mar 17.
Coal gasification wastewater (CGW) contains several types of aromatic pollutants, which impart high biotoxicity and reduce the quality of anaerobic treatment. Two types of hydrolysis acidification processes, namely microaerobic hybrid reactor (HA-1) and upflow anaerobic sludge blanket reactor (HA-2), were developed for pre-treatment before the anaerobic treatment. The changes in the dissolved organic matter and biotoxicity were investigated to comprehensively understand the degradation process. The results showed that HA-2 coupled with an anaerobic reactor achieved a 12.3% and 13.4% higher removal efficiency for chemical oxygen demand and total phenols, respectively, compared with the coupled process with HA-1. Furthermore, HA-2 could transform macromolecules into small molecules more efficiently and produce fewer intermediates. The coupled process with HA-2 preferentially removed complex aromatic substances with absorption wavelengths of 285 and 254 nm, according to the sequential orders interpreted from two-dimensional correlation spectroscopy. In addition, the results of fluorescence excitation-emission-matrix with regional integration analysis revealed that the contents of typical cyclic compounds in CGW, such as phenolic, heterocyclic, and polycyclic aromatic compounds were remarkably reduced by HA-2. In addition, HA-2 reduced the toxic unit value of CGW by 67.5% and increased the resazurin dehydrogenase activity of the sludge by 37.5% during CGW treatment, thus improving the biotoxicity removal and biodegradability. However, the coupled process with HA-2 did not significantly affect the "indirect estrogenic activity" of CGW. A Pearson correlation analysis indicated that spectral indicators, such as UV and Φ, presented a high positive correlation with the reduction of acute toxicity and organics.
煤气化废水（CGW）含有多种类型的芳香族污染物，具有很高的生物毒性，降低了厌氧处理的质量。开发了两种水解酸化工艺，即微氧混合反应器（HA-1）和上流式厌氧污泥床反应器（HA-2），用于厌氧处理前的预处理。研究了溶解有机物和生物毒性的变化，以全面了解降解过程。结果表明，与 HA-1 耦合的厌氧反应器相比，HA-2 耦合的厌氧反应器对化学需氧量和总酚的去除效率分别提高了 12.3%和 13.4%。此外，HA-2 能够更有效地将大分子转化为小分子，并产生更少的中间产物。根据二维相关光谱法推断的顺序，HA-2 优先去除具有 285 和 254nm 吸收波长的复杂芳香物质。此外，荧光激发-发射矩阵与区域积分分析的结果表明，HA-2 显著降低了 CGW 中典型环状化合物的含量，如酚类、杂环和多环芳烃化合物。此外，HA-2 在处理 CGW 时将 CGW 的毒性单位值降低了 67.5%，并将污泥的 Resazurin 脱氢酶活性提高了 37.5%，从而提高了生物毒性去除率和生物降解性。然而，HA-2 与 HA-1 的耦合过程对 CGW 的“间接雌激素活性”没有显著影响。Pearson 相关分析表明，光谱指标如 UV 和Φ与急性毒性和有机物的降低呈高度正相关。
