Hitachi-ge Nuclear Energy, Ltd.

Fujitec Co., Ltd.

Takashi Asano

Tsuyoshi Itou

Atsushi Yukita

Kenji Noshita

Mamoru Kamoshida

Kenichi Yamamoto

Yuko Kani

Yuuko Kani

Yusuke Kitamoto

Yosuke Goda

Noriaki Takeshi

Mamoru Harada

Provided is a method of treating radioactive liquid waste which reduces the amount of radioactive waste to be generated and is capable of removing a radioactive nuclide from radioactive liquid waste to the extent that the concentration thereof is less than or equal to the measurement lower limit using a simple apparatus configuration. A filtration device is connected to a colloid removal device by a connection pipe. An adsorption tower positioned at the highest stream of an adsorption device is connected to the colloid removal device by a connection pipe. The colloid removal device includes an electrostatic filter. Respective adsorption towers in the adsorption device are sequentially connected by a pipe. A discharge pipe is connected to the adsorption tower positioned at the lowest stream of the adsorption device. Radioactive liquid waste, containing particles having a particle diameter of 1 &#x3bc;m or greater, negatively charged colloids, and a radioactive nuclide, is supplied to the filtration device. The particles having a particle diameter of 1 &#x3bc;m or greater are removed by the filtration device and the negatively charged colloids are removed by the electrostatic filter that is positively charged. The radioactive nuclide is removed by the adsorption tower.

Method of treating radioactive liquid waste and radioactive liquid waste treatment apparatus

Granular crystalline silicotitanate (CST) is supplied from an adsorbent raw material supply apparatus into a caustic treatment apparatus. A sodium hydroxide solution of 1 Mol/L in a caustic agent supply apparatus is supplied into the caustic treatment apparatus with the granular CST supplied. After a predetermined quantity of the sodium hydroxide solution is supplied to the caustic treatment apparatus, the supply of the sodium hydroxide solution to the caustic treatment apparatus is stopped. The granular CST is left to stand for 0.5 hour in the state that it is immersed in the sodium hydroxide solution in the caustic treatment apparatus and is subjected to the caustic treatment. After that, the granular CST subjected to the caustic treatment is cleaned by cleaning water in a cleaning water supply apparatus. The respective adsorptive performances of cesium and strontium of the granular CST subjected to the caustic treatment are improved more.

Radionuclide adsorbent, method of producing radionuclide adsorbent and production apparatus thereof

A radioactive waste (zeolite to which Cs-137 was adsorbed) in a waste tank and a glass raw material (soda lime glass) in a glass raw material tank are supplied into a solidifying vessel. Graphite in a graphite tank is also supplied into the solidifying vessel. The solidifying vessel is filled with a mixture of the radioactive waste, glass raw material, and graphite and is then disposed in an adiabatic vessel. The radioactive waste and glass raw material in the adiabatic vessel are heated by thermal energy generated due to radiation emitted from Cs-137. The heat is transferred to the peripheral portion of the solidifying vessel through the graphite, raising the temperature of the peripheral portion. The glass raw material is melted and enters clearances among the radioactive waste, producing a vitrified radioactive waste. This radioactive waste solidification method can shorten a time taken to produce a vitrified radioactive waste.

Radioactive waste solidification method

The invention provides an elevator apparatus comprising a cagedisposed inside a path of upward or downward movement vertically movably, a counterweightvertically movable with the upward or downward movement of the cage, and a lift drive mechanism for driving the cageupward or downward. The drive mechanism comprises a sheavedisposed inside the path, ropesextending along a route around the sheave, and a drive devicein engagement with the ropes. The drive devicecomprises a belt transmission provided alongside the ropesand revolvingly movable along the rope extension route, a mechanism for pressing a belt surface of the belt transmission into contact with the ropes, and a drive motor for driving the belt transmission. The cage can be driven upward or downward without using any traction sheave, while the cage can be reduced in weight.

Both-way movable body driving mechanism and elevator using the same

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Hitachi, Japan

Takashi Asano