Kabushiki Kaisha Toshiba

Mitsubishi Cable Industries, Ltd.

The Tokyo Electric Power Company, Incorporated

Shuichi Ohmori

Michitsugu Mori

Yutaka Asanuma

Hiroyuki Hayami

Tadashi Narabayashi

Takashi Okamura

Hirokazu Kuzushita

Mikihide Nakamaru

Makoto Yasuoka

Kenji Kumagai

Toshikazu Gozen

Terunobu Iio

A silica optical fiber is provided, which contains a pure-silica core and a cladding layer formed on the pure-silica core, wherein the pure-silica core contains a C element and has a content of elements belonging to the third period-the seventh period of the periodic table, except Si element that constitutes the quartz structure, of not more than 100 ppm. The present invention can provide a silica optical fiber superior in the resistance to high energy electromagnetic waves such as UV light and &ggr;-rays.

Silica optical fiber

A feed water heating system for heating a feed water for a power-generating plant having a steam turbine, a condenser and a steam generator, comprises: a steam injector unit for receiving a plurality of bled steams having different pressures extracted from the steam turbine and an effluent water discharged from the condenser to mix the effluent water with the plurality of bled steams to raise the temperature and pressure of a mixture of the effluent water with the plurality of bled steams to deaerate and discharge the temperature and pressure raised mixture. The steam injector unit comprises: a multistage steam injector having a plurality of steam injectors connected in series for receiving one of the plurality of bled steams and a feed water to mix the one of the plurality of bled steams with the feed water to raise the temperature and pressure of a mixture of the one of the plurality of bled steams and the feed water to discharge the temperature and pressure raised mixture; a cylindrical container for housing therein the multistage steam injector; and a jet centrifugal deaerator, provided downstream of the multistage steam injector, for receiving a feed water discharged from the multistage steam injector and the bled steams to apply a centrifugal force to the feed water and the bled steams to deaerate the feed water to spatially separate a deaerated feed water from the bled steams to discharge the deaerated feed water.

Feed water heating system for power-generating plant

Growing community of inventors

Yokohama, Japan

Shuichi Ohmori