Biogas Purification
Biogas produced in the anaerobic digestion process should be dehumidified, desulfurized prior to be dispatched to the next unit of upgrading, for the conversion into biomethane.
In this section we find the following items:
- Safety torch: if operating problems should occur in the plant, the torch will burn the biogas produced;
- Carbon filters for hydrogen sulphide (H2S) removal;
- Biogas dehumidification system;
- Blower for pressurization of biogas for the feeding of upgrading;
- Gasometer.
The gasometer is used to maintain, in the event of fluctuations of the biogas production, a constant pressure to the biomethane upgrading system and to allow the cogenerator to always work at maximum speed. The gasometer to service the plant has a capacity less than 100 m3 and is made entirely of stainless steel, against the 1.000 m3 of a typical installation made with plasticized PVC tarpaulins (tarpaulins are not resistant to winds, snow and last for a few years, against 30 years of minimum duration of the gasometers in stainless steel).
It is also not subject to regulation of the deposits of combustible gases in fixed tanks, or in hazardous activities according to CEI 64-2. Therefore the system will not need to appropriate storage tanks of water for fire protection with the simplified authorization of the fire department.