Biogas produced in anaerobic digester can not be used immediately because it contains a large number of impurities and harmful substances, which must be purified before it can be put into the pipeline for normal use at home. What equipment is better for biogas purification and purification?
In the specific design of biogas purification process, the initial investment and later operation cost of the project should be considered first, and the specific equipment should be determined according to the flow range and process requirements of biogas. The following small series for you to introduce three kinds of process methods for reference.
1. Pressure swing adsorption
With activated carbon molecular sieve, the energy consumption is low, but the loss of methane is relatively high. This process requires pre desulfurization.
2. Chemical absorption
For example, for amine method, the methane loss can be very low, good can reach 0.1%. But it requires a lot of heat and chemicals, and it also requires pre desulfurization.
3. High pressure washing
High pressure water washing also has a problem of methane loss, which can be controlled to 1% or even 0.5% by good manufacturers.
Some people often think that the energy consumption of high-pressure water washing is high. In fact, the energy consumption of biogas purification and purification mainly occurs in the stage of biogas pressurization. After purification, biogas needs to be pressurized. If this part of energy consumption is removed in time, the energy consumption of high-pressure water washing is not high. The water for washing can be recycled and the actual consumption of water is very low. The treated tail gas can be used in vegetable greenhouse to provide CO2 for plant growth.