LIU Lei-bin,GAO Shou-you,LI Yi.Study on the Technology of Controlling Dissolved Oxygen in Reflux Mixed Liquid by Deoxy Tank[J].China Water & Wastewater,2022,38(16):52-56.
Study on the Technology of Controlling Dissolved Oxygen in Reflux Mixed Liquid by Deoxy Tank
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第38卷
Number:
第16期
Page:
52-56
Column:
Date of publication:
2022-08-17
- Keywords:
- deoxy tank; dissolved oxygen; reflux mixed liquid
- Abstract:
- To solve the problem that dissolved oxygen in reflux mixed liquid leads to the decrease of denitrification efficiency in anoxic tank, the concentration of dissolved oxygen in the reflux mixed liquid and its consumption of biodegradable organic matter in wastewater were analyzed, and the engineering measure of setting up a deoxy tank was proposed. Field tests in three wastewater treatment plants showed that the dissolved oxygen in the mixed liquid decreased rapidly after the aeration stopped, and the dissolved oxygen decreased by 1.24 mg/L, 2.78 mg/L and 1.86 mg/L within 30 min, respectively. The deoxy tank effectively controlled the dissolved oxygen in reflux mixed liquid with an average dissolved oxygen removal amount of 1.81 mg/L and an oxygen consumption rate of 2.22 mgDO/(gVSS·h). The deoxy tank was arranged at the end of the aerobic tank with a stirrer to prevent sludge settling and facilitate degassing. The designed hydraulic retention time (HRT) is suggested to be 0.5 h, which can be flexibly applied to AAO and multi-stage AO processes to improve the nitrogen removal performance of wastewater treatment plants, and it can be used in the upgrading of wastewater treatment plants or new projects.
Last Update:
2022-08-17