BOD (Biochemical Oxygen Demand) is an environmental monitoring indicator that can be used to determine the situation of organic matter in water. Under normal circumstances, organic matter can be decomposed by microorganisms. However, when microorganisms decompose organic matter in water, they consume a certain amount of oxygen. If the dissolved oxygen in water is insufficient to meet the needs of microorganisms, it will cause water pollution.
After understanding the function of BOD, it can be known that it is very necessary to detect BOD in water! It is a comprehensive indicator representing aerobic pollutants such as organic matter in water and can comprehensively reflect the content of organic matter in water. Therefore, the BOD-8000 – BOD rapid measurement instrument is widely used in water quality monitoring and analysis. BOD has become an important indicator for water quality monitoring and also an important basis for water body environment monitoring and sewage treatment.
In addition, to ensure comparability during the BOD re-detection process, a time period is usually specified, and the consumption of dissolved oxygen in the water is also measured. The five-day period, known as the five-day biochemical oxygen demand, will be recorded as BOD5. If the BOD value in water is higher, it indicates that there is more organic matter in the water and the pollution will be more serious. Pollution monitoring related to organic matter is an important indicator in water environment monitoring.
The calculation method of biochemical oxygen demand is as follows:
1.BOD (mg/L) = (D1-D2)/P;
2.D1: Initial dissolved oxygen (mg/L) of the diluted water sample;
3.D2: Dissolved oxygen (mg/L) of the diluted water sample after being incubated in a constant temperature incubator at 20 ℃ for 5 days;
4.P= [Volume of water sample (mL)] / [Final Volume of diluted water sample (mL)]
It should also be noted that the ratio of BOD to COD can indicate how much of the organic pollutants in it are difficult for microorganisms to decompose. If organic matter that is difficult for microorganisms to decompose is polluted, it will cause great harm to the environment.
