2023 Volume 79 Issue 25 Article ID: 23-25013
Continuous monitoring of influent NH4-N in a sewage treatment plant was carried out for three years, operation plans were formulated based on these data, and energy saving measures, N2O control measures, and active management were evaluated using a sewage treatment plant simulator. The seasonal variation of influent NH4-N tended to be higher in winter, and the range between minimum and maximum values was wide. The daily fluctuation showed a typical fluctuation pattern with the lowest value in the early morning and the highest value in the morning throughout the year. As an operation plan, lowering the DO setting value during low-load hours as an energy-saving measure reduced the aeration air volume by 5.2%, resulting in a 0.5% reduction in GHG emissions for the entire treatment plant. As a water treatment N2O control measure, doubling the return sludge rate during times of high load reduced N2O emissions by 12.0%. Active management resulted in a 5% increase in nitrogen supply and a 58% reduction in power consumption CO2. By continuously monitoring of influent quality and making operation plans, we were able to confirm that improving the operation management of the current process would lead to a reduction in GHG emissions.
