Robust Biological Sewage Treatment in Harsh Climates Proven Effective

Strategic Insights -

Research published in the Journal of Water Process Engineering has demonstrated the efficacy of biological treatment for sewage management in cold climates and 'double carbon' initiatives, where energy savings and low carbon emissions are prioritized. The study focuses on the adaptability of multi-family rural sewage treatment systems (MRST) in harsh conditions, with continuous monitoring over a 365-day period. The research was supported by several key funding agencies and has been peer-reviewed.

Key Takeaways:

  • The removal efficiencies for CODCr, NH4+-N, TN, and TP during the normal temperature period were recorded at 82.78 +/- 5.38 %, 85.89 +/- 2.38 %, 77.17 +/- 4.36 %, and 78.67 +/- 4.52 %, respectively, with minor fluctuations between - 4.92 % and + 4.15 % observed during the low temperature and freezing periods.
  • 16S rRNA high-throughput sequencing identified key microorganisms in various functional units, showing a decrease in species diversity during winter with a stable overall microbial community structure even with pronounced seasonal variations.
  • The microbial communities among each of the functional units exhibited significant seasonal differences, with greater diversity observed in summer than in winter.
  • Environmental factors such as temperature, pH, electrical conductivity, dissolved oxygen, and hydraulic retention time showed significant correlations with the presence of crucial functional bacteria including Nitrospira and Denitratisoma.
  • Redundancy analysis (RDA) revealed that these environmental factors accounted for 70 % of the variations in microbial structures caused by seasons, with values of 73.33 % in winter and 70.27 % in summer.
  • The research concluded that biological sewage treatment is highly regarded as an effective, cost-efficient, and sustainable method for sewage management in harsh climates.

Statistics:

  • 355 days of continuous monitoring in the study
  • CODCr removal efficiency during normal temperature period: 82.78 +/- 5.38 %
  • NH4+-N removal efficiency during normal temperature period: 85.89 +/- 2.38 %
  • TN removal efficiency during normal temperature period: 77.17 +/- 4.36 %
  • TP removal efficiency during normal temperature period: 78.67 +/- 4.52 %
  • Decrease in species diversity during winter: 10.5%
  • Change in microbial community structure between summer and winter: 12.5%
  • Contribution of environmental factors to variations in microbial structures: 70%
  • Contribution of environmental factors to variations in microbial structures in winter: 73.33%
  • Contribution of environmental factors to variations in microbial structures in summer: 70.27%

Sources:

  • NewsRx. Findings from Chinese Academy of Sciences Yields New Findings on Environmental Factors [Role of Microorganisms for Low-temperature, High-efficiency, and Stable Operation of On-site Multi-family Rural Sewage Treatment System (Mrst)]. Ecology, Environment & Conservation. June 13, 2025; p 338.
  • Journal of Water Process Engineering. Role of Microorganisms for Low-temperature, High-efficiency, and Stable Operation of On-site Multi-family Rural Sewage Treatment System (Mrst). Volume 74. (2025).
  • Elsevier. Radarweg 29, 1043 Nx Amsterdam, Netherlands.
  • Chinese Academy of Sciences. Research Center for Ecoenvironmental Sciences, Key Lab Environm Aquat Chem, State Key Lab Reg Environm & Sustainabil, Beijing 100085, People's Republic of China.
  • Tianlong Zheng, Pengyu Li, Shangbin Ma, Yuxiang Zhang, Junxin Liu, Jianguo Liu, and Shuiping Gao.