The BOD meter is used to determine water quality. Different uses have different requirements for water quality. If the water quality is not good, the creatures and animals in water will also be affected to a certain extent. Drinking water requires high quality, and has stricter regulations on the physical properties of the water, total salinity, total hardness, bacteria and harmful substances content, etc.
Biochemical Oxygen Demand (BOD) refers to the mass concentration of dissolved oxygen required in the biochemical process of the decomposition of organic matter by microorganisms in water under aerobic conditions. In order to make the measured value of BOD comparable, a time period is generally specified, and the dissolved oxygen consumption in water is measured. Generally, five days are used, called the five-day biochemical oxygen demand, which is recorded as BOD5. The larger the BOD value, the more organic matter contained in the water, and therefore the more serious the pollution.
BOD is an environmental monitoring indicator used to monitor the pollution of organic matter in water. Organic matter can be decomposed by microorganisms, and oxygen is consumed in this process. If the dissolved oxygen in water is not enough to meet the needs of microorganisms, the water body is in a polluted state.
When there are biodegradable organic matter in the water sample, the organic matter is assimilated by the microorganisms in the biofilm, and the cell respiration of the microorganisms is also enhanced, which consumes a part of the dissolved oxygen and reduces the dissolved oxygen that diffuses on the surface of the oxygen electrode. When the diffusion rate (mass) of dissolved oxygen in the water sample to the electrode reaches a constant value again, a constant current is generated. Because the difference between the two constant currents has a quantitative relationship with the concentration of biodegradable organic matter in the water sample, therefore, after the current signal is amplified and analyzed by a microcomputer, the BOD detection result can be directly displayed.
It is also an important experiment to use a BOD meter to measure water quality. The BOD meter adopts the microbial electrode method, which can quickly determine the BOD value in the water sample, and is easy to operate with high accuracy. The principle of BOD meter is based on the oxygen consumption and metabolism of organic matter by microorganisms. The determination of BOD only involves the initial oxidation rate, so the determination of a sample can be completed within 8-15 minutes, which greatly shortens the time required for the determination.
