Low cost environmental protection biochemical treatment for sewage

According to different requirements of microbial growth on oxygen environment, it can be divided into aerobic biochemical treatment and anoxic biochemical treatment. Anoxic biochemical treatment can be divided into facultative biochemical treatment and anaerobic biochemical treatment.

In the process of aerobic biochemical treatment, aerobic organisms must grow and reproduce in the presence of a large amount of oxygen to reduce the organic matter in wastewater.

In the process of facultative biochemical treatment, facultative microorganisms only need a small amount of oxygen to grow and reproduce and degrade organic substances in wastewater. If there is too much oxygen in the water, the facultative microorganisms will not grow well, which will affect their treatment efficiency of organic matters.

The facultative microorganism can adapt to high concentration wastewater, the concentration of COD in the influent can be increased to more than 2000 mg/L, and the removal rate of C0D is generally 50-80%. Aerobic microorganisms can only adapt to wastewater with low COD concentration. The influent COD concentration is generally controlled below 1000-1500 mg/L, and the COD removal rate is generally 50-80%. The time of facultative biochemical treatment and aerobic biochemical treatment should not be too long, generally 12-24 hours.

Biochemical technology

People use the similarities and differences between facultative biochemical treatment and aerobic biochemical treatment to combine facultative biochemical treatment and aerobic biochemical treatment, so that wastewater with high COD concentration is first treated by facultative biochemical treatment, and then the effluent treated by facultative tank is used as the inlet water of aerobic tank. This combined treatment can reduce the volume of the biochemical tank, not only saving environmental investment, but also reducing the daily operation cost.

The principle and function of anaerobic biochemical treatment and facultative biochemical treatment are the same. The difference between anaerobic biochemical treatment and facultative biochemical treatment is that Anaerobic Microorganisms do not need any oxygen in the process of reproduction, growth and organic matter degradation, and Anaerobic Microorganisms can adapt to wastewater with high COD concentration (4000-10000mg/L). The disadvantage of anaerobic biochemical treatment is that the biochemical treatment time is very long, and the retention time of wastewater in the anaerobic biochemical tank generally needs more than 40 hours.