Volatile fatty acids (VFAs) from waste activated sludge (WAS) via alkaline fermentation have been shown to provide an effective alternative carbon source for biological nutrient removal in wastewater treatment plants (WWTPs) that promotes the subsequent release of phosphorus (P) and refractory dissolved organic matter. The dewatering ability of fermented sludge is known to decrease during alkaline fermentation. Here, a novel strategy of initiating fermentation at a pH of 10 was developed to improve VFA purity, P removal efficiency, and fermented sludge dewaterability during WAS fermentation. Although VFAs concentration was lower (1.69 ± 0.09 g COD/L) when the pH was only initially adjusted to pH 10 (R_IA) relative to when the pH was maintained at 10 on a daily basis (R_DC), the purity of VFAs in the fermented liquid was improved (58.48%). Furthermore, the release of total phosphorous (TP) in R_IA was 5.90 times lower than that in R_DC (139.37 mg/L). The normalized capillary suction time and specific resistance to filtration in R_IA decreased to 42.23% and 40.70%, respectively, suggesting that the dewaterability of fermented sludge also improved. The amount of alkali needed was 17.44 kg for each ton of total solid (TS) in R_IA, which was 5.49 times lower than that in R_DC. Thus, approximately 45.44 USD was saved in operational costs for each ton of TS processed in R_IA. These results indicated that VFAs production via initial pH 10 fermentation was a robust and cost-efficient way for providing carbon resources in WWTPs.

已经显示，通过碱性发酵从废活性污泥（WAS）中获得的挥发性脂肪酸（VFA）可为废水处理厂（WWTP）中的生物营养去除提供有效的替代碳源，从而促进随后释放的磷（P）和难熔的溶解物有机物。已知在碱性发酵过程中发酵污泥的脱水能力降低。在这里，开发了一种在10 pH值下启动发酵的新策略，以提高VFA纯度，P去除效率和WAS发酵过程中发酵污泥的脱水性。尽管挥发性脂肪酸浓度较低（1.69±0.09克COD / L）时将pH仅最初调节至pH 10（R _IA相当pH保持在10每天的基础上向）（R _DC），提高了发酵液中VFA的纯度（58.48％）。此外，总磷R中的释放（TP）_IA比R中降低5.90倍_DC（139.37毫克/升）。归一化的毛细管吸入时间和比电阻R中过滤_IA分别降至42.23％和40.70％，这表明发酵污泥的脱水性也提高。R _IA中每吨总固体（TS）所需的碱量为17.44 kg，比R _DC中的碱量低5.49倍。因此，约45.44美元被保存在操作成本中的R处理的TS的每个吨_IA。这些结果表明，通过初始pH 10发酵生产VFA是为污水处理厂提供碳资源的可靠且经济高效的方式。