Mitsubishi Hitachi Power Systems, Ltd.

Kvaerner Power Oy

Ivo International Oy

Valmet Technologies Oy

Fortum Oyj

Pauli Dernjatin

Takahiro Marumoto

Kati Savolainen

Hirofumi Okazaki

Kenji Kiyama

Koji Kuramashi

Toshihiko Mine

Kenichi Ochi

Hidehisa Yoshizako

Kenso Arita

Hitoshi Wakamatsu

Marko Huttunen

Juha Lepikko

Marko Fabritius

Kari Jääskeläinen

Naoya Imooka

Hideo Okimoto

Lauri Pietikäinen

Jouko Heikkilä

Antti Heinolainen

Jukka RÖPPÄNEN

An oxygen combustion system includes a boiler to burn fuel using combustion gas composed of oxygen-rich gas and circulating flue gas, a dust remover disposed in a flue through which flue gas discharged from the boiler flows, a second flue leading the combustion gas to the boiler, the combustion gas being made by mixing the circulating flue gas extracted downstream of the dust remover with the oxygen-rich gas, a combustion gas heater exchanging heat between the flue gas flowing between the boiler and dust remover and the combustion gas flowing through the second flue, and a flue gas cooler disposed between the heater and the dust remover to cool the flue gas. A control unit controls at least one of a flow rate and cooling medium temperature of the flue gas cooler such that temperature of the flue gas introduced into the dust remover will be between 90&#xb0; C. and 140&#xb0; C.

Oxygen combustion system and method for operating same

A boiler operating method operates a boiler by switching between air combustion mode and oxygen combustion mode when burning fossil fuel with first combustion gas and second combustion gas. The second combustion gas compensates for oxygen deficiency in the first combustion gas. The air combustion mode uses air as the first combustion gas and the second combustion gas while the oxygen combustion mode uses mixed gas of combustion flue gas and oxygen-rich gas as the first combustion gas and the second combustion gas, the combustion flue gas being produced when the fossil fuel is burned. By mixing the oxygen-rich gas in the air in the process of switching between air combustion mode and oxygen combustion mode, the air being the first combustion gas used in the air combustion mode, the boiler operating method can switch between the air combustion mode and oxygen combustion mode while maintaining stable combustion.

Boiler and operating method of same

To inhibit corrosion of water wall tubes of a boiler and stabilize combustion on a burner during oxygen combustion operation, a boiler combustion system includes a boiler equipped with a burner and a two-staged combustion gas input port; a flue gas supply fan extracting flue gas from a flue gas treatment system via a flue gas circulation line; a combustion gas supply line, fuel carrier gas supply line, and two-staged combustion gas supply line branched off from the flue gas circulation line downstream of the flue gas supply fan; an oxygen supply line supplying oxygen-rich gas to the combustion gas supply line and fuel carrier gas supply line; combustion air supply fans; a switching unit switching operation between the flue gas supply fan and the combustion air supply fans; and dampers regulating gas flow rates on the combustion gas supply line and the two-staged combustion gas supply line, respectively.

Boiler combustion system and operation method therefor

The invention relates to a combined fluidized bed and pulverized coal combustion method and system. In the method, fluidizing air () is injected into a fluidized bed () situated in the bottom portion of the combustion chamber (). Into the combustion chamber, to above the fluidized bed (), is fed a mixture of pulverized coal and a carrier gas from a second set of fuel feed means () at a mass flow rate which is higher or at least substantially equal to the upper ignition limit of the mixture, and the mixture of the pulverized coal and the carrier gas at least by the fluidizing air (), and at least a fraction of the fuel fed via the second set of fuel feed means () is combusted above the fluidized bed ().

Combined fluidized bed and pulverized coal combustion method

Method and apparatus for reducing nitrogen oxide emissions from burning

Growing community of inventors

Helsinki, Finland

Pauli Dernjatin