HE Wei-peng,QU Meng-jun,SHI Zhou,et al.Characteristics of Membrane Fouling Mitigated by Different Cleaning Agents in BF/UF Combined Process[J].China Water & Wastewater,2021,37(19 19):33-39.
Characteristics of Membrane Fouling Mitigated by Different Cleaning Agents in BF/UF Combined Process
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
19 19
Page:
33-39
Column:
Date of publication:
2021-10-01
- Abstract:
- A lab-scale experimental device was established for the combined process of ballasted flocculation (BF) and ultrafiltration (UF) using microsand as the carrier. The effect of the microsand dosage on the ultrafiltration efficiency and membrane fouling was analyzed, and the flux attenuation, fouling reversibility and flux recovery rate of the contaminated membrane were investigated when citric acid, NaOH and NaClO solutions were used for separate cleaning. A cake layer with special structure and good water permeability was formed on the UF membrane by adding appropriate amount of microsand in the BF process, which was conducive to improving the membrane specific flux, slowing down the membrane fouling after washing and improving the effluent quality during the UF process. However, it could not effectively inhibit the accumulation of the irreversible membrane fouling. Different types and concentrations of agents were selected for separate chemical cleaning of the contaminated membranes. The performance of alkali cleaning was better than that of the oxidant cleaning, while the acid cleaning had the worst cleaning performance among the three types of chemical cleaning. The reason was that the ability to remove various kinds of pollutants for each cleaning agent was quite different, leading to a significant difference in the degree of irreversible fouling removal. In addition, the mitigation mechanisms of the membrane fouling under different chemical cleaning conditions were preliminarily revealed, and it was pointed out that the type and concentration of the chemical cleaning agent should be taken into account in the actual operation to optimize the cleaning performance.
Last Update:
2021-10-01