PATENT ABSTRACTS 177

5160604

TOXIC SUBSTANCE-DETECTING SYSTEM WITH FIXED

MICROORGANISM MEMBRANE FOR WATER QUALITY-

MONITORING

Eiichi Nakamura, Hiroaki Tanaka, Yoshihar Tanaka, Takashi Iitake, Hirosh Hoshikawa, Ibaraki, Japan assigned to Fuji Electric Co Ltd; Public Works Research Institu

A toxic substance-detecting device detects toxic substances in water by use of a microorganism sensor to ascertain the safety of aBl‘uents flowing into sewage-treating processes, environmental waters such as rivers, and waters flowing into water purification plants and a water quality- monitoring system employing a detecting device. The device includes a fixed micro-organism membrane and apparatus for circulating a buffer solution of micro-organism substrate and nutr- ient to one side of the membranne and solutions of water to be examined, standard and cleaning water to the other side.

5160621

METHOD FOR TREATMENT OF WASTE WATER BY ACTIVATED

SLUDGE PROCESS

Yoshim Nagasaki, Takao Hashimoto, Isao Takemura, Hiroshi Imai, Yasunobu Hirama, Tadayosh Nakajima, Kawasaki, Japan assigned to Ajinomoto Co Inc

A method for treatment of waste water by an ac- tivated sludge process wherein the aeration tank system is composed of three tanks: a first tank, a second tank and a third tank, in which sludge microorganisms adsorb the organic substances in the waste water to be treated and a part of them begin oxidation and decomposition of the substances in the first tank, the organic sub- stances which are adsorbed by the sludge micro- organisms are further decomposed by the microorganisms of the second tank, and the sludge microorganisms are activated in the third tank, is disclosed. The aeration amount to the respective tanks is controlled to fall within specified ratios. Further, the pH value in the aeration tank system is controlled to be slightly acidic, and the pH of the tanks increases in order from the first tank to the third tank. The process may also be carried out in a single tank using a three-step batchwise process, where the batches are subject to the aeration and pH requirements.