YANGDeng.Design for Upgrading and Transformation of a Mixed Wastewater Treatment Plant into a Domestic Sewage Treatment Plant[J].China Water & Wastewater,2025,41(22):72-77.
Design for Upgrading and Transformation of a Mixed Wastewater Treatment Plant into a Domestic Sewage Treatment Plant
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第22期
Page:
72-77
Column:
Date of publication:
2025-11-17
- Keywords:
- mixed wastewater treatment plant; domestic sewage treatment plant; in-situ upgrading and renovation; A/A/O micro-aeration oxidation ditch; high-efficiency sedimentation tank
- Abstract:
- The designed treatment capacity of a mixed wastewater treatment plant in Shantou is 6×104 m3/d, with influent consisting of printing and dyeing wastewater and domestic sewage in a ratio of 7∶3. The effluent quality must meet the stricter values of the first level A limit specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002) and the first level limit during the second phase of urban secondary wastewater treatment plants specified in Discharge Limits of Water Pollutants (DB44/26-2001) of Guangdong Province. Due to the construction of a dedicated dyeing and printing industrial wastewater treatment facility within the jurisdiction, the previously mixed wastewater treatment plant was upgraded and transformed into a domestic sewage treatment plant. The treated effluent quality is required to meet the stricter values of the original discharge standard as well as those stipulated in Discharge Standard of Water Pollutants for LianJiang River (DB44/2051-2017). The biochemical treatment system was upgraded by converting the original hydrolysis acidification tank into an anaerobic tank or an anoxic tank, and integrating an internal recirculation function. This modification transformed the initial hydrolysis acidification tank combined with an A/O process into an A/A/O micro-aeration oxidation ditch system. Additionally, advanced treatment was achieved through pipeline reconfiguration and replacement of auxiliary equipment, enabling the continued utilization of the existing high-efficiency sedimentation tank coupled with a rotary precision filter. Following the completion of the renovation, the removal efficiencies of COD, BOD5, SS, NH3-N, TN and TP increased by approximately 6%, 1%, 5%, 3%, 30% and 8%, respectively, with all effluent parameters consistently meeting and being superior to the designed discharge standards. This project demonstrates the feasibility of in?situ upgrading and renovation of the wastewater treatment plant without expanding treatment infrastructure, offering a replicable model for similar projects.
Last Update:
2025-11-17