Heterotrophic-autotrophic sequential system for reductive nitrate and perchlorate removal
Deniz Ucar1,2, Emine Ubay Cokgor1, Erkan Sahinkaya3
1a Environmental Engineering Department , Faculty of Civil Engineering, Istanbul Technical University , Maslak, Istanbul 34469 , Turkey.
Environmental Technology
|June 24, 2015
Summary
This study shows a sequential denitrification process effectively removes nitrate and perchlorate from drinking water. The combined heterotrophic-autotrophic system achieved complete contaminant reduction, ensuring safe water quality.
Area of Science:
- Environmental Science
- Water Treatment Engineering
- Microbiology
Background:
- Nitrate and perchlorate are widespread global water contaminants.
- Effective removal strategies are crucial for ensuring safe drinking water.
Purpose of the Study:
- To evaluate the performance of a sequential heterotrophic-autotrophic denitrification process.
- To assess nitrate and perchlorate removal efficiency in drinking water.
Main Methods:
- A sequential denitrification process involving heterotrophic and autotrophic reactors was employed.
- The study investigated varying nitrate loads and C/N ratios under a fixed hydraulic retention time.
- Methanol was used as a carbon source in the heterotrophic reactor.
Main Results:
- Complete removal of nitrate and perchlorate was achieved, with initial concentrations up to [Formula: see text] and 1000 µg/L, respectively.
- Maximum denitrification rates were observed at specific methanol concentrations and nitrate loads.
- Perchlorate reduction initiated in the heterotrophic stage and was completed in the autotrophic stage.
Conclusions:
- The sequential heterotrophic-autotrophic denitrification process is highly effective for removing nitrate and perchlorate.
- The process maintained effluent sulphate levels below 250 mg/L and neutral pH.
- This method offers a viable solution for treating contaminated drinking water.
Keywords:
elemental sulphurheterotrophic processnitrate reductionperchlorate reductionsequential systemMore Related Videos
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