Valmet Technologies Oy

Metso Power Oy

Valmet Power Oy

Vesa Kainu

Juha Ojanpera

Risto Eteläaho

Jukka-Pekka Leppälä

Jan Nickull

Jukka-Pekka Leppala

Risto Etelaeaho

Juha OjanperÄ

A heat exchanger pipe in a flow duct for gases. The pipe first section has a second section with an inner pipe for transferring heat transfer medium; an outer pipe that radially encloses a part of the inner pipe; and a medium layer between the outer pipe and the part of the inner pipe. The second section of the heat exchanger pipe bends less than 90 degrees. Furthermore, the first section is insulated in its entirety, or non-insulated in the vicinity of other heat recovery surfaces only. In the device the temperature of the heat transfer medium flowing in the inner pipe is at least 500&#xb0; C., the temperature of the outer surface of the outer pipe is higher than 600&#xb0; C., or an auxiliary agent is fed to the thermal device.

Thermal device, its use, and method for heating a heat transfer medium

An air nozzle arrangement for a fluidized bed boiler, comprising an air feed pipe and an air nozzle which limit an air feed duct configured to supply air to the furnace of the fluidized bed boiler. The air nozzle arrangement comprises a surface configured to guide coarse material along said surface. At least part of said surface is thermally insulated from the air nozzle and/or the air feed pipe. Furthermore, at least part of said surface is configured to protect at least part of said air nozzle and/or air feed pipe. Thus, the temperature of said surface is configured to be high when the fluidized bed boiler is in operation, whereby the solidification of molten material of the fluidized bed in the air nozzle arrangement is reduced.

Air nozzle arrangement in a fluidized bed boiler, grate for a fluidized bed boiler, and a fluidized bed boiler

A boiler includes a flue gas duct and heat exchanger pipes in the flue gas duct. The boiler includes a planar silencer plate, which silencer plate includes sound absorbing material, and said first silencer plate being placed downstream of one of said heat exchanger pipes in the flow direction of flue gases in said flue gas duct. Furthermore, a silencer for a flue gas duct with a rectangular cross-section in a boiler, the silencer including at least a first and a second planar silencer plate substantially parallel to the flow direction of flue gases, the silencer plates including sound absorbing material. The first silencer plate is placed at an angle to the second silencer plate, wherein the width of the resonating area of the flue gas duct becomes narrower in two directions transverse to the flow direction of the flue gases.

Boiler, and a silencer for a flue gas duct in a boiler

A fluidized bed boiler comprises a furnace whose lower part is equipped with a grate comprising means for supplying fluidizing air into the furnace. The furnace also comprises at least one heat transfer surface extending across the furnace and comprising elongated heat transfer tubes on top of each other. The heat transfer surface is supported on the grate from underneath, substantially over its whole length, in the section extending across the furnace.

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Kangasala, Finland

Vesa Kainu