**4. Amine based H2S and CO2 biogas scrubber**

Figure 3 illustrates the general configuration of an amine based biogas scrubber. It consists of an absorption column, a desorption column and a water wash scrubber. Initially, raw biogas enters the absorption column where the amine solution removes H2S and CO2. Then, the biogas passes through the water wash scrubber where amines traces are removed and

Fig. 3. Illustration of the amine based biogas H2S and CO2 scrubber.

the saturated amine passes through the desorption column where it is regenerated. A heat exchanger is used to cool the regenerated amine before it re-enters the absorption column.
