PURPOSE: To prevent the breakage of cells of Bacillus subtilis, etc., by passing a liquid containing Bacillus subtilis at a flow rate of ≤2m/sec through a tubular ceramic filter having inner surface constructed of spherical particles and having a specific surface roughness.
CONSTITUTION: A suspension of Bacillus subtilis stored in a vessel 1 is passed through a ceramic filter 4 with a pump 2 to effect cross-flow filtration. The filtrate is taken out of the filter vessel 3 and the concentrated suspension is returned to the vessel 1 and recycled. The ceramic filter 4 is produced by mixing a binder to high-purity alumina particles of about 10W30μm diameter, forming a tube having an outer diameter of about 19mm and an inner diameter of about 15mm, heating the tube to eliminate the binder, uniformly coating the inner surface of the formed tube with a suspension of high-purity alumina particles having particle diameter of about 2W10μm and heating the product at about 1,500°C.
IIJIMA SHINJI
MINAMI TOSHIRO
YASUDA SHUNJI
KATO YOSHIHISA
IIJIMA SHINJI
TOSHIBA CERAMICS CO