Mitsubishi Heavy Industries Limited

Mitsubishi Jukogyo Kabushiki Kaisha

Kabushiki Kaisha Meiji Gomu Kasei

Koichiro Iwashita

Susumu Okino

Toru Takashina

Naohiko Ukawa

Kazuaki Kimura

Masakazu Onizuka

Kiyoshi Okazoe

Taku Shimizu

Takeo Shinoda

Atsushi Tatani

Shigeo Hasegawa

Yoshikazu Endo

Kenji Inoue

Yoshio Nakayama

Toyoshi Nakagawa

Tamotsu Higuchi

Toshihiro Sato

Masaki Iijima

Satoshi Nakamura

Hiromitsu Nagayasu

Naoyuki Kamiyama

Tatsuto Nagayasu

Eiji Ochi

Masao Hino

Shinichiro Kotake

Satoru Sugita

Manabu Oda

Makiichi Ishihara

Tsuyoshi Ohishi

Kenji Iwasaki

Takakazu Sunada

Satoshi Yajima

Atsushi Yoshioka

Hideki Kamiyoshi

Hiroshi Baba

Heiji Tanaka

Kouji Ikeda

Masaru Sakamoto

Kouichi Shinohara

Sunao Ushio

Takami Yamada

Kenichiro Kawamichi

Noohiko Ukawa

Shoichi Onishi

Yoshimitsu Kawanishi

Tetsu Ushiku

Morikata Nishida

A flue gas desulfurization apparatus includes an absorption tower that absorbs sulfur oxide in a flue gas, and drift suppression members that are arranged near a bend portion of a purified gas exhaust passage arranged at an outlet portion of the absorption tower, the drift suppression members serving to collect mist particles.

Flue gas desulfurization apparatus

This invention relates to a method for the treatment of a desulfurization absorbing fluid after gas-liquid contact with combustion exhaust gas in which fine particles of unburned carbon and other materials are efficiently removed from the desulfurization absorbing fluid to improve the quality of a by-product (e.g., gypsum) obtained therefrom. The method of this invention comprises the steps of feeding a gas into a desulfurization absorbing fluid (A) containing fine particles of unburned carbon and other materials and thereby producing gas bubbles so as to cause the fine particles to adhere to the surfaces of the gas bubbles and create a foam phase (D) consisting of the gas bubbles; and breaking the foam phase (D) to obtain a liquid (E) containing the fine particles.

Method of processing desulfurization absorption liquid and apparatus therefor

This invention relates to a flue gas treating process including a heat recovery step for recovering heat from flue gas by means of a heat exchanger (,) and thereby cooling the flue gas, and a subsequent absorption step for bringing the flue gas into gas-liquid contact with an absorbing fluid (D) in absorption towers (,) so as to remove at least SO,present in the flue gas by absorption into the absorbing fluid (D), which is characterized, for example, in that a powder addition step for spraying a powder collectable in the absorption step into the flue gas is provided prior to the heat recovery step. This invention makes it possible to provide a flue gas treating process in which a countermeasure against SO,present in flue gas can be easily achieved without resorting to ammonia injection and the flue gas can further be purified without the disadvantage of causing the injected substance to remain in the treated flue gas.

Flue gas treating process and system

The present invention relates to a process for the treatment of arsenic-containing sludge obtained by adjusting arsenic-containing waste water to a PH of 12 or greater by the addition of a calcium compound and subjecting the waste water to solid-liquid separation, the process comprising the steps of adding a calcium compound to the arsenic-containing sludge slurry obtained by the solid-liquid separation, dewatering the resulting sludge, drying the dewatered sludge, and calcining the dried sludge. According to the present invention, arsenic-containing sludge obtained by treating waste water to precipitate arsenic present therein can be calcined to yield a calcined product which involves no risk of arsenic redissolution when it is dumped. Moreover, there is no possibility that arsenic compounds may be volatilized during calcination.

Process for the treatment of arsenic-containing sludge

Wet gas processing method and the apparatus using the same

Flue gas is treated for the presence of SO.sub.3, without resorting to ammonia injection, by adding a powder into the flue gas and subsequently bringing the flue gas into gas-liquid contact with an absorbing fluid, whereby the SO.sub.2 present in the flue gas is removed by absorption into the absorbing fluid. The treatment process may also include introducing the flue gas into a dust collector, whereby dust, including the powder present in the flue gas, is collected, and/or recovering heat from the flue gas by means of a heat exchanger, whereby the flue gas is cooled. A system for treating flue gas is also provided.

Exhaust gas desulfurization system

There is provided a method for flue gas desulfurization which is capable of conducting minute control of oxidation and which is capable of maintaining the concentration of sulfurous acid in an absorbent liquid within a proper range in a highly reliable and efficient manner, even in the case where an abrupt change occurs in the operational conditions of the system. In the method for controlling the oxidation in flue gas desulfurization, the value of proportional sensitivity K in the feed back control process, which is based primarily on the oxidation-reduction potential, is increased depending on the deviation .epsilon. in a region where the detected oxidation reduction potential value PN is below the target oxidation reduction potential value SN in correspondence with the characteristic change of the oxidation-reduction potential against the concentration of sulfurous acid.

Method for controlling oxidation in flue gas desulfurization

A corrosion preventive method and an apparatus for preventing corrosion of stainless steel components in an exhaust gas desulfurizing apparatus of an exhaust gas treatment system comprising the exhaust gas desulfurizing apparatus for removing at least sulfur dioxide by bringing exhaust gas into contact with absorbing solution, wherein specific means is employed to maintain the Cl.sup.- concentration and SO.sub.4.sup.2- concentration at a corrosion preventive side of the corrosion resisting limit of stainless steel.

Method and apparatus for preventing corrosion of exhaust gas treatment

A flue gas desulfurizer having an absorption tower for bringing untreated flue gas into gas-liquid contact with an absorbent slurry, wherein there is provided heat recovery means for recovering heat from the flue gas passing through the flue gas inlet section of the absorption tower prior to gas-liquid contact, and to boiler equipment including heat release means for releasing the recovered heat to heat utilization equipment. This invention also relates to thermal electric power generation equipment including extraction feedwater heaters for heating boiler feedwater with steam from steam turbines, a flue gas desulfurizer using an absorbent slurry, and means for recovering heat from the flue gas passing through the flue gas desulfurizer and/or the absorbent slurry within the flue gas desulfurizer, whereby boiler feedwater is preheated by the recovered heat and then introduced into the extraction feedwater heaters.

Flue gas desulfurizer, boiler equipment and thermal electric power

A wet flue gas desulfurization system for removing sulfur dioxide present in flue gas by absorption into an absorbent slurry includes an absorption tower having at a bottom thereof a tank for holding an absorbent slurry; a circulating pump for feeding the absorbent slurry within the tank to a flue gas inlet section in an upper part of the absorption tower and bringing the absorbent slurry into contact with flue gas; and a slurry preparation compartment provided on one side of the tank of the absorption tower and separated from a flue gas passage section by a partition wall having its lower end submerged below a surface of the absorbent slurry, whereby an absorbent and water constituting the absorbent slurry are directly introduced into the slurry preparation compartment.

Wet flue gas desulfurization system

A flue gas treating system for removing sulfur dioxide and dust present in flue gas by gas-liquid contact with an absorbing fluid and has an inlet side absorption tower of the liquid column type and an outlet side absorption tower of the liquid column type, each of which has a uniform cross-section over the area of gas-liquid contact, and the cross-section of flue gas in the inlet side absorption tower is smaller than the cross section of flue gas in the outlet side absorption tower. The inlet side absorption tower is constructed in the form of a parallel-flow absorption tower wherein the flue gas flows downward for favorable collection of dust and absorption of sulfur dioxide. The outlet side absorption tower is constructed in the form of a counter-flow adsorption tower wherein the flue gas flows upward for favorable absorption of sulfur dioxide. The absorbing fluid within a tank is injected upward from a plurality of spray pipes.

An object of this invention is to provide a gas-liquid contact apparatus for use in wet flue gas desulfurizers and the like which is equipped with lightweight and inexpensive header pipes having excellent wear resistance and corrosion resistance and hence exhibits high reliability and economical efficiency. To this end, there is provided a gas-liquid contact apparatus wherein one or more header pipes having attached thereto a plurality of spray nozzles for spouting a slurry upward are disposed in the main body of a tower through which a gas flows, characterized in that the header pipes are made of a fiber-reinforced resin composite material and the outer surface thereof or the outer and inner surfaces thereof are formed of a corrosion-resistant and wear-resistant layer of a resin containing ceramic particles.

Gas-liquid contact apparatus

The present invention relates to a slurry thickening tank comprising a tank body disposed below the surface of a slurry within a slurry tank, a slurry inlet provided in the upper part of the tank body, a thickened slurry outlet provided in the lower part of the tank body, and supernatant liquid withdrawal means provided in the upper part of the tank body, whereby the slurry introduced into the tank body through the slurry inlet is thickened by sedimentation in the tank body and the resulting thickened slurry is discharged from the tank body through the slurry outlet, wherein the surface of the structural member of the tank body extending from the slurry inlet to the thickened slurry outlet has an angle of inclination greater than the angle of repose for the thickened slurry, and to an absorption tower for use in flue gas desulfurization systems which is equipped with such a slurry thickening tank. This slurry thickening tank can maintain satisfactory operating conditions for a long period of time without developing any trouble such as a blockage of the thickened slurry outlet.

Slurry thickening tank and absorption tower for use in wet flue gas

This invention is related to a slurry filtration device and the wet lime-gypsum flue-gas desulfurization system comprising a slurry filtration device for the separation (concentration) of gypsum. The slurry filtration device comprises tank that has a slurry supply pipe at its upper part and a filtrate-drain hole at its bottom, a layer of filter sand lying on its bottom, a slurry accumulator arranged on the layer of filter sand, and a vibrator set in said slurry accumulator for vibrating the slurry. The present invention not only improves the solid-liquid separability remarkably but also saves cost and space.

Slurry filtration device and flue-gas desulfurization system

Growing community of inventors

Tokyo, Japan

Koichiro Iwashita