HUXiao-bing,SONGWei-wei,WANGZhen-zhen,et al.Evolution of Isolated Suspended Biofilm Properties[J].China Water & Wastewater,2024,40(11):95-102.
Evolution of Isolated Suspended Biofilm Properties
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第11期
Page:
95-102
Column:
Date of publication:
2024-06-01
- Keywords:
- suspended biofilm; biofilm evolution; floc structure; extracellular polymer substances (EPS)
- Abstract:
- The mature biofilm on the carrier surface was stripped and cultured in a reactor for 35 days to investigate the evolution of biofilm into activated sludge. The morphological characteristics of pure cultured suspended biofilm were investigated from three aspects: floc microstructure (equivalent diameter, porosity, regularity and aspect ratio), physicochemical properties of biofilm (MLSS, EPS and SVI), and wastewater treatment performance. With the extension of culture time, the biofilm disintegrated into more flocs, leading to a decrease in its equivalent diameter, fluctuation up in porosity and regularity, while the aspect ratio remained relatively unchanged. The biomass concentration of the biofilm exhibited an overall upward trend, with MLSS, MLVSS, and MLVSS/MLSS (f) peaking at 7.68 mg/mL, 6.91 mg/mL, and 0.92 respectively during the later stage of cultivation. The SVI demonstrated a fluctuating upward trajectory. The EPS exhibited a trend of initial decrease followed by an increase, with total EPS (Tol?EPS) reaching 98.19 mg/g in the late stage of cultivation. The average removal rates of COD, NH4+-N and TP reached (81.98±2.51)%, (89.86±13.67)% and (85.81±9.57)%, respectively. In conclusion, during the later stage of suspended biofilm culture, its performance indicators closely resembled those of activated sludge, indicating the evolution of the biofilm into activated sludge.
Last Update:
2024-06-01