Yin Zehui, Wang Jihong, Wang Mingran, Liu Jiandong, Chen Zhongbing, Yang Boyu, Zhu Lixin, Yuan Rongfang, Zhou Beihai, Chen Huilun
School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China.
Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha, Suchdol 165 00, Czech Republic.
Sci Total Environ. 2023 May 15;873:162341. doi: 10.1016/j.scitotenv.2023.162341. Epub 2023 Feb 23.
Alkaline fermentation can reduce the amount of waste activated sludge and prepare sludge alkaline fermentation liquid (SAFL) rich in short-chain fatty acids (SCFAs), which can be used as a high-quality carbon source for the biological nutrient removal (BNR) process. This review compiles the production method of SAFL and the progress of its application as a BNR carbon source. Compared with traditional carbon sources, SAFL has the advantages of higher efficiency and economy, and different operating conditions can influence the yield and structure of SCFAs in SAFL. SAFL can significantly improve the nutrient removal efficiency of the BNR process. Taking SAFL as the internal carbon source of BNR can simultaneously solve the problem of carbon source shortage and sludge treatment difficulties in wastewater treatment plants, and further reduce the operating cost. However, the alkaline fermentation process results in many refractory organics, ammonia and phosphate in SAFL, which reduces the availability of SAFL as a carbon source. Purifying SCFAs by removing nitrogen and phosphorus, directly extracting SCFAs, or increasing the amount of SCFAs in SAFL by co-fermentation or combining with other pretreatment methods, etc., are effective measures to improve the availability of SAFL.
碱性发酵可以减少剩余活性污泥的量，并制备富含短链脂肪酸（SCFAs）的污泥碱性发酵液（SAFL），其可用作生物营养物去除（BNR）工艺的优质碳源。本综述汇编了SAFL的生产方法及其作为BNR碳源的应用进展。与传统碳源相比，SAFL具有更高的效率和经济性，不同的运行条件会影响SAFL中SCFAs的产量和结构。SAFL可以显著提高BNR工艺的营养物去除效率。将SAFL作为BNR的内碳源可以同时解决污水处理厂碳源短缺和污泥处理困难的问题，并进一步降低运行成本。然而，碱性发酵过程导致SAFL中存在许多难降解有机物、氨和磷，这降低了SAFL作为碳源的可用性。通过脱氮除磷纯化SCFAs、直接提取SCFAs或通过共发酵或与其他预处理方法结合等方式增加SAFL中SCFAs的量，是提高SAFL可用性的有效措施。
