Mitsubishi Jukogyo Kabushiki Kaisha

Fumiya Nakashima

Kimishiro Tokuda

Toshimitsu Ichinose

Yuichi Fujioka

Satoshi Uchida

Yoshinori Kobayashi

Yoshihiko Tsuchiyama

Shigeyasu Ishigami

Keisuke Sonoda

Toshiyuki Takegawa

Masaharu Oguri

Tokuda Kimishiro

Takaharu Toyoda

In a coal gasification power generator, coal gas 500 obtained by gasifying a coal 100 by a gasifying furnace is introduced into a desulfurization furnace in which the coal gas 500 is desulfurized by limestone 400. A coal gas 501 after desulfurization is burned by a combuster 5 after it has passed through a dust removing unit 3 so that high temperature combustion gas 800 is supplied to a gas turbine. The gas turbine 7 drives a power generating unit. Exhaust gas 801 from the gas turbine is supplied to an exhaust gas boiler 8. Char 60a produced in the gasifying furnace and limestone 60b containing CaS emitted from the desulfurization furnace are burned in an oxidation furnace, and by using the resultant combustion gas, water vapor introduced from the exhaust gas boiler 8 is heated by a heat exchanger, and thereafter it is supplied to the gasifying furnace as a gas. With the above construction, chemical energy possessed by the coal is effectively converted into electric energy, and also the rate of desulfurization of coal gasifying gas is improved thereby reducing emitted sulfur oxide.

Coal gasification power generator

An improvement of a coal firing device applied to coal gasifiers, boilers for power generation, etc. On the inner walls of a ceiling portion (4) of a firing furnace (3) and of a throat portion (2) thereabove, and of a diffuser portion (6) further thereabove, where necessary, plate-like vortex breaker(s) (1A, 1B) is/are provided. Vortex flow of gas in the vicinity of the inner wall surface around the throat portion (2) is thereby weakened and molten slag sticking on the wall surface is suppressed to be pushed up by the gas. There occurs neither staying of molten slag at the diffuser portion (6) nor scattering of slag, and blockade of furnace due to solid-phase slag does not occur.

Coal firing device

In a coal gasification power generator, a coal gas 500 obtained by gasifying coal 100 by a gasifying furnace 1 is introduced into a desulfurization furnace 2 in which the coal gas 500 is desulfurized by limestone 400. A coal gas 501 after desulfurization is burned by a combuster 5 after it has passed through a dust removing unit 3 so that a high temperature combustion gas 800 is supplied to a gas turbine 7. The gas turbine 7 drives a power generating unit. An exhaust gas 801 from the gas turbine 7 is supplied to an exhaust gas boiler 8. A char 60a produced in the gasifying furnace 1 and limestone 60b containing CaS emitted from the desulfurization furnace 2 are burned in an oxidation furnace 4, and by using the resultant combustion gas, water vapor 30a introduced from the exhaust gas boiler 8 is heated by a heat exchanger 10, and thereafter it is supplied to the gasifying furnace 1 as a gas 700. With the above construction, chemical energy possessed by the coal 100 is effectively converted into electric energy, and also the rate of desulfurization of coal gasifying gas is improved thereby reducing emitted sulfur oxide.

A structure of a boiler, of the type in which pulverized fuel is burnt within a square barrel-shaped furnace having a vertical axis, is improved so that ignitability is improved and the amount of NO.sub.x produced is decreased. Burners for injecting pulverized fuel-air mixtures are disposed at the central portions of respective edges in a horizontal cross-section of a furnace wall and are inclined downwardly with respect to a horizontal plane. Also, under air nozzles for feeding air are disposed under the respective burners.

Apparatus for use in burning pulverized fuel

In order to stably maintain a combustion capability in a combustion furnace for coal gassification, it is necessary to exhaust molten slag produced within the furnace without the slag stagnating. The present invention provides, in a combustion furnace for coal gassification, a slag exhausting device which is configured in such a manner that the cooling of molten slag being exhausted from the furnace is minimized to prevent the slag from solidifying and causing other slag to stagnate. The slag exhausting device is disposed at the center of a bottom wall of the combustor, and has a lower cylindrical portion and an upper bank opening upwardly and flared at an angle of 300.degree.-45.degree.. The height H from the bottom wall to the top of the upper bank, a height L and an inner diameter ds of the cylindrical lower portion and a diameter D of the combustor are set to satisfy the relations of ds/D=0.2-0.4, L/ds=0.2-0.6 and H/D=0.05-0.15.

Coal combustor and slag exhausting device therein

Fuel, desulfurizing agent and air are fed into a fluidized bed gasification furnace so that part of the fuel is gasified. The produced combustible gas is led into a combustor. Residual fuel not gasified within the fluidized bed gasification furnace is led to a fluidized bed combustion furnace jointly with the desulfurizing agent to burn it with air fed separately to the combustion furnace. Then produced combustion gas is led into the combustor, in which the combustible gas is burnt with the combustion gas and air fed seperately to the combustor. The amounts of air fed to the respective furnaces and the combustor are individually regulated. A gasifying power generation method includes, in addition to the abovementioned steps of the gasifying combustion method, the steps of driving a gas turbine by the combustion gas produced by the combustor, driving a steam turbine by steam generated by the combustion gas, and rotating electric generators by the respective turbines to carry out power generation.

Growing community of inventors

Tokyo, Japan

Fumiya Nakashima