BOD is a measure of the amount of oxygen required to remove waste organic matter from water in the process of decomposition by aerobic bacteria (those bacteria that live only in an environment containing oxygen).,
Does pH affect BOD?
Bacteria that treat waster water to reduce the COD and BOD, are extremely sensitive to pH! So pH can also have a huge effect on activated sludge COD and BOD reduction rates. Also, some compounds can be precipitated, or dissolved, like heavy metals or suspended solids, at various pH ranges.
How does BOD affect water quality?
Higher BOD indicates more oxygen is required, which is less for oxygen-demanding species to feed on, and signifies lower water quality. Inversely, low BOD means less oxygen is being removed from water, so water is generally purer.
Why BOD test is done?
Biochemical oxygen demand, or BOD, is a chemical procedure for determining the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period.
What is the permissible limit of BOD in wastewater?
In general, maximum allowable concentration for direct environmental wastewater discharge fall around 10 mg/L BOD and maximum allowable concentrations for discharge to sewer systems around 300 mg/L BOD.
Does chlorine reduce BOD?
BOD reduction: Chlorine accomplishes BOD reduction by oxidation of organic compounds present in wastewaters. 4. Oxidation of metal ions: Metal ions which are in reduced state are oxidized by chlorine (e.g., ferrous to ferric ion and manganous to manganic ions).
What is BOD and why is it important?
The BOD is an important parameter for assessing water quality. It deals with the amount of oxygen consumption (mg O2 L− 1) by aerobic biological organisms to oxidize organic compounds. Sewage with high BOD can cause a decrease in oxygen of receiving waters, which in turn can cause the death of some organism.
How is BOD related to sewage?
Wastewater from sewage treatment plants often contains organic materials that are decomposed by microorganisms, which use oxygen in the process. (The amount of oxygen consumed by these organisms in breaking down the waste is known as the biochemical oxygen demand or BOD.
What is BOD and COD in sewage treatment plant?
The biochemical oxygen demand (BOD) represents the amount of dissolved oxygen (DO) consumed by biological organisms when they decompose organic matter in water. The chemical oxygen demand (COD) is the amount of oxygen consumed when the water sample is chemically oxidised.
What is the BOD of treated water?
The biochemical oxygen demand for treated water should be zero. Since it represents the amount of biodegradable organic matter present in water which is food for bacteria or microorganism, if not treated can cause several water-borne diseases.