MICROORGANISM PREPARATION INJECTION METHOD, MICROORGANISM PREPARATION AUTOMATIC INJECTION DEVICE, AND WASTEWATER PROCESSING SYSTEM

The microorganism preparation feeding method of the invention employs an automatic microorganism preparation feeding apparatus which includes a cold storage apparatus for refrigeration-storing a seed microorganism belonging to the aerobic microorganism group including at least one species of aerobic microorganisms capable of decomposing oil and fat contained in oil/fat-including wastewater and a growth tank for growing the seed microorganism so as to produce the microorganism preparation, wherein the seed microorganism belonging to the aerobic microorganism group is maintained in a live state by means of the cold storage apparatus, the seed microorganism is periodically grown by means of the growth tank so as to produce a predetermined microorganism preparation, and the produced predetermined microorganism preparation is fed to the oil/fat-including wastewater. The method includes refrigeration-storing, as the seed microorganism, a microorganism whose population density is 1×107CFU/mL to 5×109CFU/mL in the cold storage apparatus; growing, as a source material, the seed microorganism of a predetermined volume by means of the growth tank so as to produce the predetermined microorganism preparation whose volume is 50 to 500 times the predetermined volume of the seed microorganism and whose population density is 1×107CFU/mL to 2×1010CFU/mL; and feeding the produced microorganism preparation to the oil/fat-including wastewater.