If biogas wants to be widely used, it needs the step of biogas purification. After biogas purification, it can greatly reduce the composition of water, carbides and sulfides in biogas. This also constitutes the three major systems of biogas purification equipment. Here we will give you a detailed introduction, hoping to be helpful to you all!
1. Dehydration and desulfurization systems
The removal of water vapor is mainly carried out in the condenser. The methane with saturated water vapor coming out of the anaerobic reactor is cooled and condensed in the condenser to achieve the purpose of drying.
H2S is removed by box desulfurization equipment, and the continuous regeneration process of dry desulfurization is adopted. Dry desulfurization is a process of desulfurization by filling a certain height of desulfurizer in the desulfurization equipment. Biogas is removed from bottom to top through desulfurizer, and H2S is removed. Among them, the desulfurizer takes iron oxide as the main active catalytic component, and adds a variety of promoters and carriers. The desulfurization rate can reach more than 90% by catalytic action at room temperature and pressure. After treatment and purification, the H2S content in biogas should be less than 200 ppm.
2. Decarbonization system
Pressure swing adsorption (PSA) is an approximate isothermal process. It utilizes the different adsorption capacity of different components on adsorbents in gas medium. The adsorbents are selectively adsorbed when the pressure rises and regenerated when the pressure decreases.
Biogas is first filtered to remove particulate matter from the gas; then compressed into an oil-free compressor with a pressure of about 2-4 bars; then cooled by a water cooler to remove heat generated during the compression of biogas; and finally compressed biogas is transported to the adsorption bed, where CH4 is separated from CO, H2S and other components of biogas.
When the adsorbent bed is saturated and the gas production can no longer meet the minimum natural gas purity, the adsorbent bed must be regenerated. The regeneration of the adsorbent bed must reduce the pressure of the bed from the operating pressure (2-4 barg) to the atmospheric pressure. An on-line and off-line conversion of the adsorption bed is realized by a valve pipeline controlled by a microprocessor.
After dehydration, desulfurization and decarbonization, the methane content of CH4 reaches more than 90%, which can be used as the purity of natural gas. After being buffered by the methane tank, the methane is transported by the high-pressure natural gas transporter for off-site sale.
Okay, that's the highlight of this issue. I don't know if my little friends understand it after reading it. If you have any questions, you can always consult the official website of biogas purification online customer service personnel: http://www.dh-gwsg.com! Thank you very much for your support!