1、 Microorganisms gradually adapt to the temperature of the surrounding environment during their growth and metabolism, but this adaptation process usually takes a long time. The seasonal transition in southern cities is not obvious, but in the north, after autumn rain, when the environmental temperature suddenly drops, microorganisms find it difficult to adapt easily in the short term. Therefore, according to the temperature changes in previous years, sewage treatment plants should prepare corresponding plans in advance. When the temperature begins to drop in autumn, they should slowly replace the activated sludge to steadily improve the adaptability of microorganisms to low-temperature weather. It is best to complete this operation by the end of October to ensure the stable operation of the biochemical system.
2、 During this period of changes in incoming water quality, the biochemical system transitions from the summer when water volume is high and water quality is low to the autumn when water volume is low and water quality is high. It is even more necessary for sewage treatment plant managers to closely monitor the content of various nutrient components in sewage, especially in the northern region where heating is needed in early November. Cleaning heating equipment can produce a large amount of sewage with high or low pH in the short term, which can easily impact the urban sewage treatment biochemical system. Based on years of experience in sewage treatment operations, it is necessary to prepare chemicals and dosing equipment in advance and adjust them in a timely manner according to the actual situation.
3、 The control of sludge age: In autumn and winter, the microbial activity in activated sludge is relatively low, so most people choose to increase sludge concentration to maintain activity. The control of sludge concentration varies in different regions. The management personnel of the sewage treatment plant should increase the sludge concentration to the normal range of previous years before the end of October. If the sludge concentration is increased by not desliming or less desliming in a short period of time, the microbial growth time will be too long, which will lead to excessive aging of sludge, and eventually lead to biological foam or sludge swelling. Therefore, sewage plant workers should gradually reduce the amount of sludge discharged from now on to ensure stable discharge of remaining sludge. While ensuring stable discharge of sludge, some relatively gentle measures should be taken to control the sludge age, which requires a longer process adjustment.
