In this process pressurized water at low temperature is used for CO2 removal. The H2S free biogas enters in the CO2 scrubber at bottom and chilled water at pressure 7 to 8.5 bar is sprayed at the top. In these condition CO2 from the biogas gets removed. The upgraded biogas exits the scrubber. Spent water from scrubber is taken to stripping column where dissolved CO2 stripped with low pressure ad and air stripping. Now this strip water is ready to use again in CO2 scrubber for CO2 scrubbing.
Advantages of CO2 Scrubbing by water:
- High methane content in Clean Gas (up to 97% methane)
- High energy efficiency with minimum methane loss to scrubbing medium
- High level of automation resulting in easier operation of the system
- No expensive chemicals required
- Small process water requirement due to regeneration
- Consistent results; even for part load operation
