EP 0856129 A1 19980805 - METHOD AND APPARATUS FOR CONTROLLING THE TEMPERATURE OF THE BED OF A BUBBLING BED BOILER

Title (en)

METHOD AND APPARATUS FOR CONTROLLING THE TEMPERATURE OF THE BED OF A BUBBLING BED BOILER

Title (de)

VERFAHREN UND VORRICHTUNG ZUR BETT-TEMPERATURKONTROLLE EINES DAMPFKESSELS MIT EINER STATIONÄREN WIRBELSCHICHT

Title (fr)

PROCEDE PERMETTANT D'AGIR SUR LA TEMPERATURE DU LIT D'UNE CHAUDIERE A LIT EN EBULLITION ET APPAREIL CORRESPONDANT

Publication

EP 0856129 A1 19980805 (EN)

Application

EP 96934842 A 19961018

Priority

FI 9600553 W 19961018
FI 955011 A 19951020

Abstract (en)

[origin: WO9715784A1] The present invention relates to a method and assembly for controlling the bed temperature in a fluidized-bed boiler, particularly in boilers fired with coal or other fuels of high heat value but difficult to gasify. Above the fluidized bed (6), but below the freeboard (8), is arranged a cooling zone (19) and the fluidizing gas is injected into a portion of the bed at an excess rate per unit area, whereby over the area of increased fluidizing gas injection, the bed is expanded upward into the cooling zone, wherefrom unburned combustible material and the particulate matter of the bed can fall back in the bed. The gas injection (9) with the higher flow rate is arranged to the center of the fluidized bed, whereby the return circulation can occur past the waterwall portions enclosing the cooling zone, thus facilitating efficient heat transfer from the refluxed bed material in the form of radiation absorbed by the heat transfer surfaces of the cooling zone waterwalls.

IPC 1-7

F23C 11/02; F22B 31/00; F23C 7/00; F23C 9/00

IPC 8 full level

F23C 7/00 (2006.01); F23C 9/00 (2006.01); F23C 10/02 (2006.01); F23C 10/20 (2006.01)

CPC (source: EP)

F23C 7/002 (2013.01); F23C 9/003 (2013.01); F23C 10/02 (2013.01); F23C 10/20 (2013.01)

Designated contracting state (EPC)

AT BE CH DE DK ES FI FR GB GR IE IT LI NL PT SE

DOCDB simple family (publication)

WO 9715784 A1 19970501; AU 7301796 A 19970515; CZ 117198 A3 19980916; EE 9800118 A 19981015; EP 0856129 A1 19980805; FI 100064 B 19970915; FI 955011 A0 19951020; FI 955011 A 19970421; HU P9903894 A2 20000328; HU P9903894 A3 20001128; LV 12095 A 19980720; LV 12095 B 19980920; PL 326315 A1 19980914; SK 48798 A3 19981202

DOCDB simple family (application)

FI 9600553 W 19961018; AU 7301796 A 19961018; CZ 117198 A 19961018; EE 9800118 A 19961018; EP 96934842 A 19961018; FI 955011 A 19951020; HU P9903894 A 19961018; LV 980071 A 19980416; PL 32631596 A 19961018; SK 48798 A 19961018