Biogas Purification By Water Scrubbing Technology
By maintaining this continuous process of absorption, dehumidification, methane recovery, and water recycling, the biogas is purified efficiently, resulting in high-quality methane gas suitable for further processing.
Key Stages:
1. Absorption of CO₂
The biogas, containing both CO₂ and methane (CH4), comes into contact under pressurized condition with the water. Through a counter-current absorption process, CO₂ is absorbed by the water molecules.
The CO₂-rich water is then collected in a water holding tank for further treatment.
2. Dehumidification
After the absorption process, the biogas is passed through a dehumidifier to maintain optimal humidity levels.
At this stage, a biogas analyzer is employed to monitor the level of purification. The biogas is maintained at the required pressure before proceeding to the next stage.
3. Methane Recovery
During CO₂ absorption, a small amount of methane (CH4) also dissolves in the water. This absorbed methane is recovered in a flash tank using a depressurization technique.
The released methane is then directed to the knockout drum of the compressor, where it is recycled back into the process during compression.
4. Water Recycling & Degassing
The water, now containing traces of CO₂, is recycled through a degassing tower.
In this tower, a counter-current reaction between pressurized air and water removes the absorbed CO₂, purifying the water
Once purified, the water is collected back into the water holding tank for reuse in the absorption tower.
Carbon Dioxide (CO₂) Removal Process in Biogas Purification By Water Scrubbing Technology
