College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), 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 (Hunan University), Ministry of Education, Changsha 410082, PR China.
Bioresour Technol. 2018 Nov;267:141-148. doi: 10.1016/j.biortech.2018.07.018. Epub 2018 Jul 10.
This study reported a new, renewable and high-efficient strategy for anaerobic fermentation, i.e., using free ammonia (FA) to pretreat waste activated sludge (WAS) for 1 d and then combining with rhamnolipid (RL), by which the short-chain fatty acids (SCFA) production was remarkably improved. Experimental results showed the maximal SCFA production of 324.7 ± 13.9 mg COD/g VSS was achieved at 62.6 mg FA/L pretreatment combined with 0.04 g RL/g TSS, which was respectively 5.95-fold, 1.63-fold and 1.41-fold of that from control, FA pretreatment and RL pretreatment. Mechanism investigations revealed that FA + RL enhanced sludge solubilization and hydrolysis, providing more organics for subsequent SCFA production. It was also found that the combined method inhibited acidogenesis and methanogenesis, but the inhibition to methanogenesis was much severer than that to acidogenesis. Finally, the feasibility of NH-N and PO-P, released in fermentation liquor, being recovered as magnesium ammonium phosphate (MAP) was confirmed.
本研究报道了一种新的、可再生和高效的厌氧发酵策略，即使用游离氨（FA）预处理剩余活性污泥（WAS）1 天，然后与鼠李糖脂（RL）结合，从而显著提高了短链脂肪酸（SCFA）的产量。实验结果表明，在 62.6mg FA/L 预处理条件下，与 0.04g RL/g TSS 结合，可获得最大的 324.7±13.9mg COD/g VSS 的 SCFA 产量，分别是对照组、FA 预处理和 RL 预处理的 5.95 倍、1.63 倍和 1.41 倍。机理研究表明，FA+RL 增强了污泥的溶解和水解，为后续 SCFA 的生成提供了更多的有机物。还发现，该联合方法抑制了产酸和产甲烷作用，但对产甲烷作用的抑制比产酸作用更为严重。最后，确认了发酵液中释放的 NH-N 和 PO-P 作为磷酸铵镁（MAP）回收的可行性。
