Which parameter is used to estimate the strength of wastewater's organic matter?

Which parameter is used to estimate the strength of wastewater's organic matter?

• A. pH
• B. Temperature
• C. Turbidity
• D. BOD

Answer: (D)

The main concept is that the strength of wastewater’s organic matter is measured by how much oxygen the organic material would consume biologically. This is captured by Biochemical Oxygen Demand (BOD). A higher BOD means more biodegradable organic material is present, so more oxygen would be needed by microorganisms to break it down. In practice, the standard test incubates a sample with a seed of microorganisms and measures the oxygen consumed over a set period (typically five days) to express strength as mg/L of oxygen used. pH isn’t a measure of organic load; it’s about acidity or basicity of the water and can influence microbial activity but doesn’t quantify organic matter. Temperature affects the rate of biological processes but not the amount of organic matter itself. Turbidity indicates how cloudy the water is due to suspended solids, which can include organic material, but it doesn’t directly quantify the biodegradable portion. Therefore, BOD is the best parameter for estimating the strength of wastewater’s organic matter.

The main concept is that the strength of wastewater’s organic matter is measured by how much oxygen the organic material would consume biologically. This is captured by Biochemical Oxygen Demand (BOD). A higher BOD means more biodegradable organic material is present, so more oxygen would be needed by microorganisms to break it down. In practice, the standard test incubates a sample with a seed of microorganisms and measures the oxygen consumed over a set period (typically five days) to express strength as mg/L of oxygen used.

pH isn’t a measure of organic load; it’s about acidity or basicity of the water and can influence microbial activity but doesn’t quantify organic matter. Temperature affects the rate of biological processes but not the amount of organic matter itself. Turbidity indicates how cloudy the water is due to suspended solids, which can include organic material, but it doesn’t directly quantify the biodegradable portion. Therefore, BOD is the best parameter for estimating the strength of wastewater’s organic matter.