Patent ID: 8329456

Claim:
A bioreactor system for converting a feed gas containing at least one of CO or a mixture of CO 2 and H 2 to a liquid product under anaerobic conditions and delivering the liquid product to a product containing liquid, said system comprising: a) an asymmetric hydrophilic membrane having a gas contacting side in contact with the feed gas, a liquid contacting side in contact with the product containing liquid, a bio-layer with a thickness of at least 50 μm defining a plurality of bio-pores having effective diameters of at least 1 μm and not exceeding 100 μm over at least a portion of the pore length for retaining microorganisms therein, a porous surface on the bio-layer defining the gas contacting side and arranged to present open ends of the bio-pores to the feed gas, and a hydration layer occluding an end of the bio-pores opposite the porous surface of the bio-layer comprising a semi-permeable skin rated at a nominal MWCO of less than 300 kDa and a thickness of less than 10 μm arranged to control the flow of product containing liquid from the bio-layer and define the liquid contact side of the membrane while providing delivery of nutrients and moisture to the microorganisms, wherein the asymmetric membrane is arranged to transport the feed gas and the liquid products in co-directional flow from the gas contacting side to the liquid contacting side; b) a feed gas supply conduit for supplying feed gas; c) a feed gas chamber in fluid communication with the gas supply conduit and the gas contacting side of the membrane for supplying feed gas to microorganisms retained in said bio-pores; d) a liquid circulation chamber in fluid communication with the liquid contacting side of the membrane for supplying water and nutrients to the microorganisms; e) microorganisms retained in said bio-pores that require a feed gas containing at least one of CO or a mixture of CO 2 and H 2 gas and having an oxygen concentration of less than 1000 ppm; and, f) a liquid recovering conduit for transferring liquid products from the bioreactor system.