1. Microbial decomposition method: The circulating water flow is used to disperse the pollutants in the malodorous gas into the water, and the microorganisms are cultured to degrade the pollutants in the water into low-harm substances. Deodorization efficiency can reach 70%. However, due to the influence of microbial activity, the cultured microorganism can only process one or several gases of similar nature. In order to improve the treatment efficiency and stable operation, it is necessary to frequently add chemicals, control PH value, temperature, etc., so that the operation cost is relatively high. There are also a lot of labor, and once the organism dies, it will take a long time to re-cultivate.
2. Activated carbon adsorption method: The initial treatment efficiency can reach 65%, but it is very easy to saturate. It usually fails in a few days, needs to be replaced frequently, and needs to find a treatment method for waste activated carbon. The operation and maintenance cost is high, and it is suitable for low concentration. The gas with large air volume has obvious effects on alcohols and fats, but the effect of exhaust gas with high humidity is not obvious, and it is easy to cause secondary pollution of the environment.
3. Plasma method: It can reach more than 80% under normal operating conditions, and can process a mixture of a variety of odors, which is not affected by humidity and has no secondary pollution. However, the power consumption is large, and it also needs to be cleaned, the operation and maintenance cost is high, and it is easy to cause an explosion for a high concentration of flammable and explosive gas.
4. Deodorization method of plant spray liquid: The malodorous gas is neutralized and absorbed by spraying the plant extract liquid into the space for generating malodorous gas to achieve the purpose of deodorization, and the deodorization effect can reach 50%. Different odors choose different spray liquids, plant spray liquids need to be added frequently, and equipment needs to be maintained. The operation and maintenance costs are high, which may cause secondary pollution.
5. Photocatalytic oxidation method: It has the advantages of deep oxidation at room temperature, small secondary pollution, low operating cost, etc., together with the advantages of low preparation cost, good chemical stability and anti-wear performance of nano-TiO2, and photocatalytic oxidation depth in industrial waste gas. In terms of purification, it shows great potential for application.