The invention relates to a process for preparing a viable
bacillus firmus preparation. According to the process, after
bacillus firmus undergoes first-stage germ amplification culture and second-stage germ amplification culture, the
bacillus firmus is inoculated to a
fermentation culture medium for culture, and the number and conversion ratio of
bacilli is increased through feeding a supplement
carbon source during
fermentation, so that the unit yield is increased remarkably, and the
unit cost is reduced; at the end of
fermentation, fermentation liquor is concentrated with a vacuum film
concentrator, so that soluble synergistic substances,
growth promoting substances and bacteriostatic active substances can be effectively recovered from the fermentation liquor; the concentrated fermentation liquor is subjected to
drying and granulating by multi-level low-temperature spray-fluidized
drying equipment, granules are subjected to sorting,
fine powder gathered by a
cyclone separator returns and is granulated again, and then, a bacillus firmus product, of which the CFU of
powder per
gram is not less than 1.0*10<11>, is obtained;
exhaust gas is treated and is discharged after reaching standard. The process has the advantages that effective substances in the fermentation liquor can be reserved to the maximum, the quality of the product is high, the equipment utilization ratio is high, the retention of
biological activity is relatively good,
waste gas and waste water are discharged after reaching standard, and large-scale industrial production can be achieved.