Fuji Electric Co., Ltd.

Nobuyuki Motoyama

Takayuki Morioka

Hiroshi Hoshikawa

Takeo Takahashi

Ryutaro Takahashi

Sizuo Suzuki

Takanori Toyoshi

Tuyoshi Ishikawa

Mitsumasa Okada

Toshio Uede

Yasuji Shimizu

Takeo Moniwa

A process for the treatment of water with ozone in which trace amounts of organic substances contained in water to be treated are oxidized and decomposed by diffusing ozone into the water introduced into a reaction tank, by injecting a chelate compound into the water to be treated after or just before the introduction of the water into the reaction tank. Preferred chelate compounds include ethylenediaminetetraacetic acid disodium salt, ethylenediaminetetraacetic acid calcium salt, ethylenediaminetetraacetic acid magnesium salt, ethylenediaminetetraacetic acid iron salt and iron citrate.

Water treatment process with ozone

A method of oxidatively decomposing a radioactive ion-exchange resin is described, the method comprising oxidatively decomposing a radioactive ion-exchange resin containing an anion-exchange resin with hydrogen peroxide used as an oxidizing agent in the presence of iron and copper ions used as catalysts, wherein the weight ratio of hydrogen peroxide to the ion-exchange resin, that is the ratio of the net weight of hydrogen peroxide to the dry weight of the ion-exchange resin containing an anion-exchange resin, is held to be no higher than 17 and the pH of the reaction system is adjusted to be within the range of 0.5 to 6, or citric acid ions are preliminarily adsorbed on the radioactive ion-exchange resin before it is subjected to decomposition treatment or citric acid ions coexist with the radioactive ion-exchange resin in the oxidatively decomposing system, and an apparatus used for conducting the method is also described.

Method of treating radioactive ion-exchange resins by oxidative

Growing community of inventors

Kawasaki, Japan

Nobuyuki Motoyama