Valmet Technologies Oy

Metso Power Oy

Kvaerner Pulping Oy

Tero Luomaharju

Jani Lehto

Michael G Alliston

Pekka Lehtonen

Timo Mero

Ari Kokko

Mikko Varonen

Pasi Yli-hemminki

A method and an arrangement for optimizing combustion conditions in a fluidized-bed boiler, in which combustion gas is fed at two or more height levels, the first of which is a primary level (P) which is located at the height of a furnace bottom and the second is a secondary level (S) which is located above fuel feed height (F), above which secondary level (S) there can be still other combustion gas feed levels (T, . . . ). At least one combustion gas feed level (P, S, T, . . . ) is fed at different points of the furnace () in its horizontal direction with combustion gases having different oxygen contents such that zones of different oxygen content can be formed in the horizontal direction of the furnace ().

Method and arrangement for optimising combustion conditions in a fluidised-bed boiler

A method for treating fly ash of flue gas exiting a furnace of a fluidized bed boiler. A side flow conveying a first fraction of fly ash is separated from a flow conveying a second fraction of fly ash. After the separation, the side flow conveying the first fraction has a higher solids content than the flow conveying the second fraction. The first fraction of fly ash is separated from the side flow at a separation temperature of at least 400&#xb0; C., whereafter the first fraction of fly ash is discharged from the process.

Method for treating fly ash in a fluidized bed boiler and boiler plant

A process chamber is placed in connection with a circulating fluidized bed reactor for utilizing internal or external circulation of solid material or both in heat transfer purposes. Said process chamber is located inside the furnace of the circulating fluidized bed reactor adjacent to at least one of the furnace walls. The interior of said process chamber is provided with heat exchanger means for heat transfer from the solid material to heat transfer medium inside the heat exchanger means. The process chamber comprises a top closed barrier wall forming the roof of the process chamber, wherein the inlet of the solid material into the process chamber is arranged to the lower part of the wall of the process chamber and the outlet of the solid material out of the process chamber is arranged to the upper part of the wall of the process chamber. Prior to the said process chamber in the direction of the flow of said solid material an inlet chamber is provided inside the furnace of the circulating fluidized bed reactor for directing the solid material to the inlet of the process chamber.

Process chamber in connection with a circulating fluidized bed reactor

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Kämmenniemi, Finland

Tero Luomaharju