Respirometer Systems and Applications, LLC

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.

Aerobic Biodegradation Tests

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.


Nitrification Tests

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.


Anoxic Denitrification Tests

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.


Anaerobic Biodegradation (BMP) Tests

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.