Oki Electric Industry Co. said Monday its semiconductor-manufacturing unit, Miyagi Oki Electric Co., has developed an effective bacteria-based system to treat waste water.

The new system is expected to reduce the amount of organic waste water -- or industrial waste water in which organic substances are concentrated -- by 70 percent, or 1,980 tons per year.

It will save 35 million yen in annual waste-disposal consignment costs, Oki Electric said.

The system has improved waste-water decomposition efficiency by 50 percent and allows Miyagi Oki to treat 97 percent of its waste water internally.

Previously, Miyagi Oki treated 90 percent of the alkaline waste water at its internal facility using bacteria, with the remainder thermally recycled by outside waste disposers.

This method involved disposal costs and risked accidental spillage during transportation.