Related Experiment Video
Updated: Jul 18, 2026
10:19
Three-Dimensionally Printed Microfluidic Cross-flow System for Ultrafiltration/Nanofiltration Membrane Performance Testing
Published on: February 13, 2016
Filter clogging in coarse pore filtration activated sludge process under high MLSS concentration
M R Alavi Moghaddam1, Y Guan, H Satoh
1Department of Civil and Environmental Engineering, Amirkabir University of Technology (AUT), Hafez St, Tehran, Iran. alavi@aut.ac.ir
Summary
High filamentous bacteria abundance reduces filter clogging in coarse pore filtration activated sludge processes. This hybrid system replaces conventional settling tanks with coarse pore filters, impacting microbial communities.
Area of Science:
- Environmental Engineering
- Microbiology
- Wastewater Treatment
Background:
- Coarse pore filtration activated sludge (CPF-AS) is a hybrid wastewater treatment process.
- It replaces conventional secondary settling tanks with non-woven, coarse pore filter modules.
- This study investigates microbial community impacts on filter clogging under high MLSS concentrations.
Purpose of the Study:
- To determine the effect of microbial community structure on filter clogging in CPF-AS.
- To compare clogging under aerobic and anoxic/aerobic (A/A) conditions with high MLSS.
- To identify key factors influencing filter performance.
Main Methods:
- Operated CPF-AS systems under aerobic and A/A conditions with high Mixed Liquor Suspended Solids (MLSS).
- Monitored filter clogging progression over time.
- Analyzed microbial community structure, including filamentous bacteria and metazoa.
- Measured Extracellular Polymeric Substances (EPS) content.
Main Results:
- Filter clogging initiated earlier and was more severe in the A/A process compared to the aerobic process.
- EPS content and metazoa did not significantly correlate with filter clogging.
- A higher relative abundance of filamentous bacteria was observed in the aerobic sludge during clogging.
Conclusions:
- Filamentous bacteria abundance is a key factor influencing filter clogging severity in CPF-AS.
- Increased filamentous bacteria may mitigate filter clogging, particularly under aerobic conditions.
- Understanding microbial dynamics is crucial for optimizing CPF-AS performance.
Related Concept Videos
00:53Filtration
Filtration is a physical separation process that involves passing a suspension through a porous medium to separate solids from fluids. During filtration, solids collect on the porous medium while liquids, also collectively known as the filtrate, pass through. The filtration medium is selected based on the filtration purpose, quantity, and nature of the precipitate. The general criteria for a suitable filtering medium are that it is inert, mechanically strong, nonabsorbent toward dissolved...
01:06Coagulation
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
01:09Colloidal precipitates
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
01:30Biological Treatment of Effluent and Waste Water
Biological wastewater treatment relies on the metabolic activity of microorganisms to remove pollutants from sewage. In modern treatment systems, this process is organized into sequential stages that progressively reduce solid material, dissolved organic matter, and microbial contamination. Each stage plays a distinct role in improving water quality and preparing the effluent for safe discharge or reuse.Primary and Secondary TreatmentPrimary treatment is a physical process that removes large...