There are two kinds of biological desulfurization process, one is integrated, the other is separated. Comprehensive biological desulfurization is to introduce a certain amount of air into the biogas containing hydrogen sulfide, and the mixed gas is removed by biological filter. In this way, plastic packing is installed in the reactor, and the circulation of nutrient solution keeps the packing in a wet state and replenishes the nutrition needed for desulfurization. Integrated desulfurization efficiency is high, 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 will 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 ℃), the system is easy to lose control. If the biodesulfurization product is sulfuric acid, a large amount of low concentration sulfuric acid will be formed, which is difficult to treat. Similarly, it is not possible to treat biogas with concentrations of hydrogen sulfide above 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 alkali in the mixed liquid to remove hydrogen sulfide from the biogas. The absorption liquid from the biological scrubbing tower 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 from separator. The single 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 deal with methane with high concentration of hydrogen sulfide. However, the operation cost is slightly higher than that of integrated biological desulfurization.
Both of them are widely used in biogas, landfill gas, natural gas, water gas and other industrial gas. The integrated biological desulfurization process has low operating costs and is widely used in power generation and combustion projects with low concentration of hydrogen sulfide (less than 10000 ppm). The single biological desulfurization process has a strong ability to resist hydrogen sulfide load, and the air will not enter the biogas. It is widely used in biological desulfurization and purification process of high concentration hydrogen sulfide.
The above is a detailed introduction of the new process principle of biological desulfurization. I believe you have already understood it. If you want to know more information, please click Official website.