LINGWei-wei,MAShun-jun,TANGYu-lin.Design and Application of the pH Adjustment and Aluminum Control System by Gas/Liquid Carbon Dioxide[J].China Water & Wastewater,2024,40(6):91-96.
Design and Application of the pH Adjustment and Aluminum Control System by Gas/Liquid Carbon Dioxide
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第6期
Page:
91-96
Column:
Date of publication:
2024-03-17
- Keywords:
- waterworks; carbon dioxide; poly aluminum chloride
- Abstract:
- Aiming at the issue of pH increase in raw water caused by algal proliferation in waterworks, the design and engineering application of gas/liquid carbon dioxide (CO2) injection system was carried out in Huinan waterworks of Shanghai. The control mode combining feedforward control of raw water pH and flow rate with the feedback control of precipitation influent pH and sand filter effluent aluminum concentration is adopted to optimize the selection and installation of online pH and aluminum ion detection instruments, enabling precise online control of pH adjustment by CO2 injection. Based on the operational results from January to August 2022, the use of CO2 pre-treatment for pH adjustment and aluminum control achieved precise operation compared to the conventional method of pH adjustment using PAC. The aluminum concentration in the treated water decreased by 31% compared with the same period in 2021, while the dosage of coagulants decreased by 35%. The cost of coagulants and CO2 agents decreased by 19%, and the production of sludge from the water treatment process decreased by 27%. The results can provide technical support for the widespread application of CO2 pre-treatment in the municipal water supply industry.
Last Update:
2024-03-17