Biogas Purification By Amine Scrubbing Technology
Our Amine Scrubbing CO₂ Purification Unit is designed to remove carbon dioxide (CO₂) from biogas through an absorption process using an amine solution. The CO₂ is selectively absorbed by the amine solvent, producing a purified methane stream.
Key Stages:
1. Gas Pressurization
The biogas from the digester is slightly pressurized using a gas blower to approximately 0.6 kg/cm²g. This ensures sufficient pressure to account for system losses.
2. CO₂ Removal (MEA Absorption)
The pressurized gas stream enters the MEA (Monoethanolamine) Absorber for CO₂ removal. In this stage, CO₂ is almost completely absorbed by the MEA solution.
The remaining unabsorbed gases, primarily methane, are then routed to the next step.
3. Dehumidification
The gas, now rich in methane, passes through a Dehumidifier to remove any moisture present in the stream.
4. Methane Drying and Compression
The dried methane is then compressed and prepared for cylinder filling, depending on the sales or consumption requirements.
5. CO₂ Stripping
The CO₂-rich MEA solution is transferred to a Stripper, where CO₂ is desorbed by heating the MEA solution.
The necessary heat for this process is supplied by steam from a boiler.
6. CO₂ Venting
The desorbed CO₂, now at low pressure, is vented to the atmosphere.
7. MEA Solution Cooling and Reuse
The hot MEA solution, post-stripping, is cooled to ambient temperature via a Heat Exchanger and a Water-Cooled Cooler.
Once cooled, the MEA solution is pumped back to the absorber column for reuse in the CO₂ absorption process.
8. Heat Recovery
Approximately 60% of the heat from the process can be recovered and used to heat water up to 55°C, which can then be utilized in the digester.
Carbon Dioxide (CO₂) Removal Process in Biogas Purification By Amine Scrubbing Technology
