Patent ID: 8178330

Claim:
A process for the fermentation of a gaseous substrate comprising CO to produce one or more products the process comprising: a) passing the gaseous substrate and a liquid media stream to a gas/liquid contact zone of a bioreactor and provide a fermentation broth; b) passing the fermentation broth to a fermentation zone of the bioreactor operated at conditions to produce an effluent stream comprising products; c) taking a slip stream of the fermentation broth from the fermentation zone and recycling it to the gas/liquid contact zone d) passing the effluent stream to a separation zone operated at conditions to produce a gaseous outlet stream comprising CO and a liquid outlet stream comprising products; e) passing the liquid outlet stream to a second separation zone operated at conditions to produce a purified product stream comprising ethanol and a recycle liquid stream comprising liquid media; and f) collecting the purified product stream.