Balloon Digester for Biogas Plants
Overview
There are different types of small scale biogas digesters. Some of the biogas digesters are summarized below:
The table below gives a first comparison of the different types.
Factors |
Fixed dome |
Floating drum |
Tubular design |
Plastic containers |
|---|---|---|---|---|
Gas storage |
Internal Gas storage up to 20 m³ (large) |
Internal Gas storage drum size (small) |
Internal eventually external plastic bags |
Internal Gas storage drum sizes (small) |
Gas pressure |
Between 60 and 120 mbar |
Upto 20 mbar |
Low, around 2 mbar |
Low around 2mbar |
Skills of contractor |
High; masonry, plumbing |
High; masonry, plumbing, welding |
Medium; plumbing |
Low; plumbing |
Availability of Material |
yes |
yes |
yes |
yes |
Durability |
Very high >20 years |
High; drum is weakness |
Medium; Depending on chosen liner |
Medium |
Agitation |
Self agitated by Biogas pressure |
Manual steering |
Not possible; plug flow type |
Evtl Manual steering |
Sizing |
6 to 124 m³ digester vol |
Up to 20 m³ |
Combination possible |
Up to 6 m³ digester vol |
Methane emission |
High |
Medium |
Low |
Medium |
