National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
Sci Total Environ. 2019 Mar 25;658:1334-1343. doi: 10.1016/j.scitotenv.2018.12.218. Epub 2018 Dec 15.
Coal liquefaction wastewater (CLW) contains numerous toxic and biorefractory organics. A series of advanced treatment processes were designed to remove the dissolved organic matter (DOM) from CLW. Here, the reactivity and state of the DOM in the treatment train were studied in relation to its chemical composition by a Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) analysis. Within an isobaric group, the raw CLW possessed a high average double-bond equivalent (DBE) and low H/C values with the N- and S-containing compounds accounting for approximately 77% of the raw CLW, which represented lignin (73.6%) and condensed aromatic structures (19.8%). In addition, the flotation process removed some hydrophobic DOM compounds with highly unsaturated states, which were biorefractory compounds. Ozonation and catalytic oxidation processes preferentially removed the highly unsaturated compounds and produced more oxidized molecules. The biofiltration process impacted the organics composition by consuming oxygen-rich substances, whereas the anoxic/oxic (A/O) process converted the reactive compounds into newly formed compounds through the loss of hydrogen (unsaturation) from the original compounds. The membrane bioreactor (MBR) process was more efficient in removing the N-containing compounds with higher unsaturated states. The compounds resistant to the applied CLW treatment processes were characterized by lower molecular weights (approximately 250-350 Da), higher oxidation states (O/S > 6), numerous carboxylic groups, and non-biodegradable features.
煤液化废水（CLW）含有大量有毒且生物难降解的有机物。一系列先进的处理工艺被设计用来去除 CLW 中的溶解有机物（DOM）。在这里，通过傅里叶变换离子回旋共振质谱（FT-ICR-MS）分析，研究了处理过程中 DOM 的反应性和状态与其化学成分的关系。在等压组内，原 CLW 具有高的平均双键等效物（DBE）和低的 H/C 值，含 N 和 S 的化合物约占原 CLW 的 77%，代表木质素（73.6%）和缩合芳构化结构（19.8%）。此外，浮选过程去除了一些具有高度不饱和状态的疏水性 DOM 化合物，这些化合物是生物难降解的化合物。臭氧氧化和催化氧化过程优先去除了高度不饱和的化合物，并产生了更多氧化的分子。生物过滤过程通过消耗富含氧的物质来影响有机物组成，而缺氧/好氧（A/O）过程通过从原始化合物中损失氢（不饱和）将反应性化合物转化为新形成的化合物。膜生物反应器（MBR）过程更有效地去除具有更高不饱和状态的含 N 化合物。对应用于 CLW 处理工艺的化合物具有较低的分子量（约 250-350 Da）、较高的氧化态（O/S > 6）、大量的羧酸基团和不可生物降解的特征。
