WATER TREATMENT METHOD, WATER TREATMENT SYSTEM, METHOD FOR PRODUCING DENITRIFYING AGENT, AND APPARATUS FOR PRODUCING DENITRIFYING AGENT

摘要

A water treatment method for performing a biological nitrification/denitrification treatment by adding an organic carbon source, the method including: an oily layer separation step of separating an oily layer containing a fatty acid from a crude glycerin waste solution that is produced as a by-product in a fatty acid alkyl ester primary production step using an oil or fat as a raw material, thereby collecting an aqueous layer containing glycerin; an alcohol separation step of separating a monohydric alcohol from the aqueous layer that is collected in the oily layer separation step; and a denitrification treatment step of adding an aqueous layer produced by separating the monovalent alcohol in the alcohol separation step as the organic carbon source for the biological nitrification/denitrification treatment. According to the water treatment method, it becomes possible to reduce the emission amount of a greenhouse gas and it also becomes possible to use an existing facility.