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09:50
Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
Expediting COD removal in microbial electrolysis cells by increasing biomass concentration
Hanieh Aboutalebi1, Arumugam Sathasivan, K C Bal Krishna
1Department of Civil Engineering and Construction, Curtin University, Kent St., Bentley, Western Australia 6102, Australia.
Bioresource Technology
|January 4, 2011
Summary
This study investigated microbial biomass effects on chemical oxygen demand (COD) removal using electrochemical reactors. Higher initial microbial concentrations significantly enhanced COD removal rates in wastewater treatment.
Area of Science:
- Environmental Science
- Microbiology
- Electrochemistry
Background:
- Wastewater treatment relies on microbial processes to remove pollutants.
- Electrochemical methods offer an alternative or complementary approach for wastewater remediation.
- Optimizing microbial biomass concentration is crucial for enhancing treatment efficiency.
Purpose of the Study:
- To investigate the impact of varying microbial biomass concentrations on chemical oxygen demand (COD) removal.
- To evaluate the performance of a two-compartment electrochemical reactor system for wastewater treatment.
- To assess the influence of biomass on COD removal rates and ammonia removal.
Main Methods:
- Utilized three sets of two-compartment electrochemical reactors with cation exchange membranes (CEMs).
- Applied a constant voltage of 0.5 V, using graphite rods and granules as electrodes.
- Varied the initial volatile suspended solids (VSS) concentration to represent different microbial biomass levels.
Main Results:
- The highest COD removal rate (40 ± 2.0 ppm/h) was observed at an initial VSS of 6130 mg/l.
- The slowest COD removal rate (23 ± 1.2 ppm/h) occurred at an initial VSS of 3365 mg/l.
- Concurrent removal of ammonia was also observed during the electrochemical treatment process.
Conclusions:
- Microbial biomass concentration significantly influences the efficiency of COD removal in electrochemical reactors.
- Higher microbial concentrations lead to accelerated COD removal rates.
- Further research is needed to optimize this bio-electrochemical system for practical wastewater treatment applications.
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