LIULiang,LIUWei-hua,LIUZhi-xiao.Characteristics of Grit Distribution in Municipal Wastewater and Grit Removal Efficiency of Different Grit Chambers[J].China Water & Wastewater,2023,39(21):61-66.
Characteristics of Grit Distribution in Municipal Wastewater and Grit Removal Efficiency of Different Grit Chambers
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第21期
Page:
61-66
Column:
Date of publication:
2023-11-01
- Keywords:
- municipal wastewater; grit chamber; grit particle distribution; grit removal rate; multilayer vortex process
- Abstract:
- This paper collected the wastewater samples from the inlet and outlet of grit chambers in six different municipal wastewater treatment plants, analyzed the distribution characteristics of grit particles, and calculated the grit removal efficiency of the grit chambers, so as to investigate the characteristics of grit distribution in domestic municipal wastewater and provide reference for optimizing the design of grit removal process. The grit concentration in municipal wastewater ranged from 1.28 mg/L to 80.96 mg/L, and the grit with particle size greater than 212 μm (coarse grit) accounted for 22.25% to 74.14%. There were obvious differences in the distribution of grit concentration and particle size in the influent of each wastewater treatment plant. The measured target grit removal diameter of the aerated grit chambers and the vortex grit chambers in each plant was between 150 μm and 212 μm, and the weighted average grit removal rate ranged from 9.16% to 52.02%. The target grit removal diameter of these chambers could be improved to less than 150 μm, and the weighted average grit removal rate could be significantly increased by reducing the surface load of the vortex grit chambers to less than 60 m/h or extending the residence time of the aerated grit chambers to more than 10 min.
Last Update:
2023-11-01