VERFAHREN ZUR KONTINUIERLICHEN FERMENTATIVEN ERZEUGUNG VON NIEDEREN ALIPHATISCHEN ALKOHOLEN ODER ORGANISCHEN LOESUNGSMITTELN.

摘要

Continuous fermentation of sugar-contg. substrates, e.g. sugarbeet molasses, to produce lower aliphatic alcohols, or organic solvents, esp. EtOH is effected in two stages, under non-aseptic conditions. The 1st stage is designed for high cell growth rates and the 2nd for high product formation rates, the vol. ratio of the 1st stage to the 2nd stage being 1:2-10. The conditions are as follows: (a) 5-20% of the total amt. of substrate is introduced into the 1st stage, and 80-95% into the 2nd stage; (b) the O2 partial pressure is ca. 3% in the 1st stage, and ca. 1% in the 2nd stage; (c) the temp. is 30-35 deg.C in the 1st stage, and 35-40 deg.C in the 2nd stage; (d) part of the effluent from the 1st stage is subjected to microfiltration and the permeate and the rest of the effluent are fed into the 2nd stage; (e) the effluent from the 2ndstage is subjected to microfiltration, the permeate is withdrawn as prod., and the retentate is partly discharged and partly recycled to the 2nd stage; (f) the various flow rates in steps (d) and (e) are controlled so that the biomass residence time is 0.5-2 hr. in the 1st stage and 5-15 hr. in the 2nd stage and the ave. cell age is 4O-100 hr.