PROBLEM TO BE SOLVED: To provide a treatment matter for a used filtering aid which can be applied to new uses, does not cause the production of an extra used filtering aid, and can be obtained stably and inexpensively and to provide a treatment method for the used filtering aid. SOLUTION: The treatment method for the used filtering aid comprises the following steps performed in the given order: the step (step 1) of mixing a used filtering aid obtained by filtering microbial cells left after fermentation with a filtering aid based on diatomaceous earth with a powdery filtering aid and a solidifying agent, the step (step 2) of curing the obtained mixture for a suitable time, the step (step 3) of granulating the cured mixture, and the step (step 4) of fermenting the obtained granules. COPYRIGHT: (C)2007,JPO&INPIT
