College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Changsha 410082, PR China.
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Changsha 410082, PR China.
Water Res. 2021 Jul 1;199:117198. doi: 10.1016/j.watres.2021.117198. Epub 2021 Apr 29.
This work proved an efficient method to significantly increase methane production from anaerobic digestion of WAS. This method is to reflux proper of digestion liquid into waste activated sludge pretreatment unit (pH 9.5 for 24 h). The yield of maximum methane improved between 174.2 ± 7.3 and 282.5 ± 14.1 mL/g VSS with the reflux ratio of digestion liquid increasing from 0% to 20%. It was observed that the biodegradable organics in the digestion liquid did not affect the biological processes related to anaerobic digestion but increased methane production through reutilization. The ammonium in the digestion liquid was the main contributor to the increase in methane production via promoting sludge solubilization, but refractory organics were the major inhibitors to anaerobic digestion. It should be emphasized that the metal ions present in the digestion liquid were beneficial rather than harmful to the biological processes in the anaerobic digestion, which may be connected with the fact that certain metal ions were involved in the expression and activation of key enzymes. In addition, it was found that anaerobes in digestion liquid were another potential contributor to the enhanced anaerobic digestion.
该工作证明了一种从 WAS 厌氧消化中显著提高甲烷产量的有效方法。该方法是将适量的消化液回流到废活性污泥预处理单元（pH9.5，24 h）。随着消化液回流比从 0%增加到 20%，最大甲烷产率从 174.2 ± 7.3 到 282.5 ± 14.1 mL/g VSS 提高。结果表明，消化液中的可生物降解有机物不会影响与厌氧消化相关的生物过程，但通过再利用可提高甲烷产量。消化液中的铵通过促进污泥溶解来增加甲烷产量，但难生物降解有机物是厌氧消化的主要抑制剂。应该强调的是，消化液中的金属离子对厌氧消化过程是有益的而不是有害的，这可能与某些金属离子参与关键酶的表达和激活有关。此外，发现消化液中的厌氧菌是增强厌氧消化的另一个潜在贡献者。
