There are two kinds of biological desulfurization processes, one is integrated and the other is separated. Comprehensive biological desulfurization is to introduce a certain amount of air into biogas containing hydrogen sulfide, and the mixed gas will remove hydrogen sulfide through biological filter. In this way, plastic packing is installed inside the reactor, and the circulation of nutrient solution keeps the packing in a wet state and replenishes the nutrition required for desulfurization. The integrated desulfurization has high desulfurization efficiency, up to 95% to 99%, low operation cost, high degree of automation, easy operation and low cost.
However, the filler of the integrated desulfurization method is easy to be blocked, which not only affects the treatment effect and increases the labor intensity, but also directly mixes the air with biogas. Once the control instrument fails, the biogas can easily reach the explosion limit, and the potential safety hazard is very high. In addition, the operation control accuracy is too high (temperature 30-31 ℃), and the system is easy to get out of control. If the biological desulfurization product is sulfuric acid, a large amount of low concentration sulfuric acid will be formed, which is difficult to treat. Similarly, it is impossible to treat biogas with hydrogen sulfide
concentration higher than 15000 ppm.
Separate biological desulfurization process adopts separate biological desulfurization method. The biogas containing hydrogen sulfide first enters the biological scrubber, where it reacts with the alkali in the mixed liquid to remove hydrogen sulfide from the biogas. The absorption liquid from the biological scrubber flows to the bottom of the tower and enters the bioreactor. There is an air distribution system at the bottom of the reactor, which provides oxygen to microorganisms, converts sulfide in the reactor into elemental sulfur, regenerates alkaline liquid, and separates elemental sulfur in the separator. The separate biological desulfurization scheme has the characteristics of high desulfurization efficiency (up to 99%), low annual operation cost, high degree of automation, easy operation and safe operation of biogas without direct mixing with air. It can treat biogas with high concentration of hydrogen sulfide. However, the operation cost is slightly higher than that of integrated biological desulfurization.
The two biological desulfurization processes are widely used in biogas, landfill gas, natural gas, water gas and other industrial gas biological desulfurization processes. The integrated biological desulfurization process has low operating cost and is widely used in power generation and combustion projects with low concentration hydrogen sulfide (less than 10000 ppm) biogas. The separate biological desulfurization process has strong resistance to hydrogen sulfide load, and air will not enter biogas. It is widely used in the biological desulfurization and purification process of high concentration hydrogen sulfide.
The above is a detailed introduction to the principle of the new biological desulfurization process. I believe everyone has understood it. If you want to know more, please click here Official website.