Carbonaceous constituents are measured by BOD, COD or TOC analyses. While the BOD has been the common parameter to characterize carbonaceous material in wastewater, COD is becoming more common in most current comprehensive computer simulation design models.
Biochemical Oxygen Demand: The BOD test gives a measure of the oxygen utilized by bacteria during the oxidation of organic material contained in a wastewater sample. The test is based on the premise that all the biodegradable organic material contained in the wastewater sample will be oxidized to CO2 and H2O, using molecular oxygen as the electron acceptor. Hence, it is a direct measure of oxygen requirements and an indirect measure of biodegradable organic matter.
Chemical Oxygen Demand: The COD test is based on the principle that most organic compounds are oxidized to CO2 and H2O by strong oxidizing agents under acid conditions. The measurement represents the oxygen that would be needed for aerobic microbial oxidation, assuming that all organics are biodegradable.
Total Organic Carbon: The total carbon analyzer allows a total soluble carbon analysis to be made directly on an aqueous sample. In many cases TOC can be correlated with COD and occasionally with BOD values. As the time required for carbon analysis is generally short, such correaltions are extremely helpful when monitoring treatment plant flows for efficiency control.