DINGXin-ya,JIANGLu-man,LIJing,et al.Fouling Characterization and Aeration Performance Recovery of Fine-pore Diffuser in Wastewater Treatment Plants[J].China Water & Wastewater,2025,41(23):91-98.
Fouling Characterization and Aeration Performance Recovery of Fine-pore Diffuser in Wastewater Treatment Plants
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第23期
Page:
91-98
Column:
Date of publication:
2025-12-01
- Keywords:
- fine-pore diffuser; fouling characterization; aeration performance; oxygen transfer efficiency; wastewater treatment
- Abstract:
- To investigate the effects of fine-pore diffuser material on foulant accumulation and oxygen transfer performance during long-term operation, high-density polyethylene (HDPE) and ethylene propylene diene monomer (EPDM) fine-pore diffuser tubes that had been in operation for several years were selected for comparative analysis. Due to the accumulation of foulants on the surface and inside the pores of fine?pore diffuser tubes, the oxygen transfer efficiencies of HDPE and EPDM tubes decreased by 26.7% and 6.4%, respectively, while the pressure losses increased to 1.25 times and 2.97 times that of the new tubes, respectively. After mechanical scrubbing, the aeration performance of the EPDM tube was almost restored to the level of a new tube. Furthermore, since most contaminants in the HDPE tube were deposited inside the pores, they could not be effectively removed by mechanical scrubbing. Although chemical cleaning significantly improved aeration performance, it still could not restore the performance to the original level. The HDPE tube exhibited a higher proportion of physically irreversible fouling, primarily due to its larger pore size, which facilitated the deposition of inorganic contaminants within the pores. Additionally, prolonged operation led to the gradual transformation of initially reversible fouling into physically irreversible forms. The physically reversible， chemically reversible and irrecoverable fouling of HDPE tube accounted for 35.8%, 42.8% and 21.4%, respectively, while for the EPDM tube, the physically reversible and physically irreversible fouling accounted for 52.9% and 47.1%, respectively. Proteins were the main component of organic pollutants in the HDPE tube, while total cells were the main component of organic pollutants in the EPDM tube. This was because microorganisms absorbed and utilized the softener in the EPDM membrane as a carbon source, promoting their growth and reproduction, and exacerbating the biofouling on the surface of the EPDM membrane.
Last Update:
2025-12-01