Schemes of key parts of the production plant were elaborated
taking both process requirements and reliability issues into account
thus making it possible to specify the equipment needed and
realistically estimate the equipment costs. A scheme of the dark
fermentation part of the plant including two bioreactors operated
in parallel is shown in Fig. 2, and a scheme of the photofermentation
part including a modular photobioreactor is shown in
Fig. 3. The gas upgrading unit including three absorbers for the VSA
process is schematically shown in Fig. 4. In all these simplified
schemes storage tanks and reserve pumps are not shown but their
costs were taken into account.