| 摘要 |
A gas-liquid contacting operation eg. in a fermentation process involving the use of a riser and downcomer communicating with each other and with a compartment above their upper ends forming a closed system is carried out with a gas pressure above the liquid in the compartment of at least 2 bars gauge, preferably 3-10 bars gauge. The efficiency of single cell protein production is significantly increased. The operation may be combined with an energy recovery system. Thus off-gas leaving the upper part of the fermenter 6 passes through a preheater 8 to a gas expander 9 which produces power for use in the compressor 10 used in supplying air to the fermenter. <IMAGE> |
