What is BOD and COD in waste water treatment?
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 COD removal in wastewater treatment?
COD Removal by Microbial Action Aerobic COD removal introduces microorganisms or bacteria that break down organic compounds present in wastewater into carbon dioxide and water in the presence of air. Aerobic COD removal is ideal for wastewater with COD < 3000 mg/L.
What is BOD and COD in ETP?
BOD means Biochemical oxygen demand. The microorganisms use organic matter as a food source through oxidation which oxygen is consumed. COD, Chemical Oxygen Demand, is a measure of the total quantity of oxygen required to oxidize all organic material into carbon dioxide and water.
Why does BOD need to be removed?
BOD is a crucial factor in refining wastewater. The bacteria are important for breaking down substances, however too much BOD can cause unwanted amounts of bacteria. Therefore it is important to control the level of BOD at every stage of the treatment process, and to remove as much as possible in the final stages.
What is BOD removal efficiency?
So, coming into the plant is 245 mg per liter of BOD and leaving there’s 22 mg per liter. We have a formula that says efficiency or removal efficiency equals what’s coming in minus what’s coming out then you divide that by what’s coming in and then we multiply by a 100 to convert the decimal to a percent.
Why is BOD and COD important?
Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) are two of the most important parameters to characterise (measure the degree of pollution) of wastewater. BOD, the biological demand for oxygen a source of water has, is the amount of oxygen used by microorganisms to break down organic substances.
What is COD of waste water?
5 Chemical oxygen demand (COD) The COD is the estimate of oxygen required for the portion of organic matter in wastewater that is subjected to oxidation and also the amount of oxygen consumed by organic matter from boiling acid potassium dichromate solution.
What is COD in STP water?
The chemical oxygen demand (COD) is a measure of water and wastewater quality. The COD test is often used to monitor water treatment plant efficiency. The COD is the amount of oxygen consumed to chemically oxidize organic water contaminants to inorganic end products.
Why is BOD important in wastewater treatment?
Biochemical oxygen demand / biological oxygen demand is an important water quality parameter because it provides an index to assess the effect discharged wastewater will have on the receiving environment. Depletion of DO causes stress on aquatic organisms, making the environment unsuitable for life.
What is the 5-day BOD of the wastewater?
The standard 5-day BOD 5 test for biological oxygen demand in wastewater is used to evaluate the effectiveness of wastewater treatment by a public or private sewer or septic system. If a system is not adequately treating its wastewater to remove biological pollutants the implication is that biological contaminants – a health hazard – are being discharged into the environment and thus potentially into local waterways and into drinking water supplies.
What is cod and BOD in waste water treatment plant?
BOD is a measure of, the amount of oxygen that requires for the bacteria to degrade the organic components present in waste water. COD or Chemical Oxygen Demand is the total measurement of all chemicals (organics & in-organics) in the waste water. BOD is biological oxygen demand and COD means Chemical oxygen demand.
What is a relationship between TOC and cod?
According to specefic definition of COD -measure the amount of organic compound which oxidized to CO2, similarly TOC – measures the amount of carbon bound to organic compound , hence the relation between COD and TOC will be directly proportional to each other.
How is BOD measured?
BOD can be measured by three different techniques – the Winkler method, by using a dissolved oxygen probe or manometrically. • The Winkler method is a titrimetric wet chemistry test that measures the amount of oxygen present based on conversion of oxygen to iodine.
