Oxygen monitoring from aerobic and anaerobic for biodegradation tests - Monitoring and Testing

Biodegradation tests involve testing samples in response to various parameters: dilution, nutrient addition, pH, temperature, and others. The pattern of oxygen uptake in aerobic tests; nitrogen gas production in anoxic denitrification tests; methane production in methanogenic tests; hydrogen production during glycolysis; and carbon dioxide production during fermentation reactions gives a measure of the rate and extent of biodegradation of the organic constituents of the test sample.

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The pattern of oxygen uptake– relative to that for a control substrate – gives a measure of the rate and extent of biodegradation of the organic constituents of the test sample. In this case, samples #2 and #3 showed a much lower biodegradation rate than the Control.

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This case study shows how respirometers were used to measure the impact of an industrial wastewater on the nitrification reaction in a treatment plant.

In this case, samples containing up to 60% wastewater by volume showed evidence of nitrification inhibition.

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Anoxic denitrification requires the presence of an organic substrate to serve as an electron donor.

This case study shows how respirometry was used to determine the effect of C/N ratio on denitrification rates.

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Anaerobic biodegradation tests – often referred to as Biochemical Methane Production (BMP) tests – involve addition of known amounts of a chemical or wastewater to anaerobic cultures. The quantity of methane production – relative to that from a control or per unit of COD added – indicates the biodegradation potential.

This case study shows methane production for a Control reactor and three test reactors that were operated at 20-, 30- and 45-day retention times and received three doses of industrial wastewater. The tests indicate that culture acclimation was required and incomplete methane production occurred for the lower SRT reactors.