PURPOSE: To prevent the release of microbes from a carrier by waterproofing an inorg. formed granular body as a carrier for microbes under specified conditions when org. materials contained in waste water are removed by biological treatment utilizing microbes.
CONSTITUTION: A foaming agent such as perlite and org. carbon evolving gas on heating and a vitrifying component are, if necessary, added to an expandable ore such as expandable shale and expandable clay, a nonexpandable ore such as clay and feldspar, and a refractory material such as silica and alumina. The mixture is crushed and granulated. The granulated material is calcined at 1,000W1,250°C to form air foam at the inside, and a granular material having ≥2mm mean particle diameter and ≥1.5sp.gr. is obtained. The granular material is deaerated at 1W10-2Torr degree of vacuum, or waterproofed by impregnating the material with ≤5wt%, an increase to the material, waterproofing adhesive or waterproofing agent at ≥0.5kg/cm2 pressure. The obtained material is used as a carrier of microbes for removing biologically org. materials in waste water and the carrier has characteristics where microbes are hardly released.
FUJITA SHIGEO
WATANABE TADASHI
