Global Patent Index - EP 2427598 A1

EP 2427598 A1 20120314 - PROCESS FOR IMPROVED LEACHING OF ELECTROSTATIC PRECIPITATOR ASH FROM A RECOVERY BOILER

Title (en)

PROCESS FOR IMPROVED LEACHING OF ELECTROSTATIC PRECIPITATOR ASH FROM A RECOVERY BOILER

Title (de)

VERFAHREN ZUR VERBESSERTEN AUSLAUGUNG VON ELEKTROFILTERASCHE AUS EINEM RÜCKGEWINNUNGSKESSEL

Title (fr)

PROCÉDÉ DE LIXIVIATION AMÉLIORÉE DE CENDRES DE FILTRE ÉLECTROSTATIQUE EN PROVENANCE D'UNE CHAUDIÈRE DE RÉCUPÉRATION

Publication

EP 2427598 A1 20120314 (EN)

Application

EP 09846901 A 20090506

Priority

SE 2009050493 W 20090506

Abstract (en)

[origin: WO2011002354A1] The invention relates to a process for purifying recovery boiler electrostatic precipitator ash (via 19) from chlorides (Cl) and potassium (K), and recover useful pulping chemicals such sodium sulphate (Na2SO4). The inventive process uses two centrifugal separation stages (2a, 2b) in series with a leaching stage (1 a and 1 b) ahead of each centrifugal stage. The chlorides and potassium is bled out (26) with the first liquid fraction (LF1 ) from the first centrifugal separation stage and the final second dry matter substance (DM2) with enriched sodium sulphate content from the second centrifugal separation stage is sent (24) to the liquor recovery cycle, mixed into black liquor before the black liquor is being sent to the recovery process for reuse of the sodium sulphate in the pulping process. With the inventive process losses of sodium sulphate could be reduced significantly compared to a one stage leach-and-centrifuge process.

IPC 8 full level

B01D 43/00 (2006.01); B01D 53/74 (2006.01); B01D 53/80 (2006.01); D21C 11/06 (2006.01)

CPC (source: EP)

D21C 11/06 (2013.01); D21H 13/00 (2013.01)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR

DOCDB simple family (publication)

WO 2011002354 A1 20110106; BR PI0924612 A2 20160830; BR PI0924612 B1 20180807; CN 102421961 A 20120418; CN 102421961 B 20130918; EP 2427598 A1 20120314; EP 2427598 A4 20140402; EP 2427598 B1 20160106

DOCDB simple family (application)

SE 2009050493 W 20090506; BR PI0924612 A 20090506; CN 200980159135 A 20090506; EP 09846901 A 20090506