Global Patent Index - EP 1044164 A1

EP 1044164 A1 2000-10-18 - IMPROVEMENTS RELATING TO THE BAYER PROCESS

Title (en)

IMPROVEMENTS RELATING TO THE BAYER PROCESS

Title (de)

VERBESSERUNG DES BAYER PROCESSES

Title (fr)

PERFECTIONNEMENTS SE RAPPORTANT AU PROCEDE BAYER

Publication

EP 1044164 A1 (EN)

Application

EP 98963023 A

Priority

  • AU PP084997 A
  • US 9826206 W

Abstract (en)

[origin: WO9929626A1] The present invention relates to a method for reducing scale in the Bayer process comprising: (a) digesting an aluminous ore in a caustic liquor to extract alumina values; (b) feeding the liquor to a settler tank to clarify the liquor by separating caustic insoluble materials; and (c) precipitating alumina crystals from the clarified liquor, the process further comprising adding a polysaccharide to the feed of the settler in an amount less than 50 ppm, said amount being sufficient to minimize the formation of scale and lengthen the time between descaling operations in comparison with a feed in the absence of polysaccharide. By using the method of the invention it is possible to substantially lengthen the time between descaling operations in some cases by over 100 %.

IPC 1-7 (main, further and additional classification)

C01F 7/04; C22B 21/00

IPC 8 full level (invention and additional information)

C01F 7/06 (2006.01); C02F 5/10 (2006.01); C22B 21/00 (2006.01)

CPC (invention and additional information)

C22B 21/0007 (2013.01); C01F 7/0653 (2013.01); C02F 5/10 (2013.01)

Designated contracting state (EPC)

IE IT

EPO simple patent family

WO 9929626 A1 19990617; AU 1813599 A 19990628; AU PP084997 D0 19980108; BR 9813467 A 20001010; EP 1044164 A1 20001018; EP 1044164 A4 20020904

INPADOC legal status


2003-11-19 [18D] DEEMED TO BE WITHDRAWN

- Effective date: 20030415

2002-11-20 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20021002

2002-09-04 [A4] SUPPLEMENTARY SEARCH REPORT

- Effective date: 20020718

2002-09-04 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A4

- Designated State(s): IE IT

2002-09-04 [RIC1] CLASSIFICATION (CORRECTION)

- Free text: 7C 01F 7/04 A, 7C 22B 21/00 B, 7C 02F 5/10 B

2000-10-18 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20000707

2000-10-18 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): IE IT