Global Patent Index - EP 1070021 A1

EP 1070021 A1 2001-01-24 - DEWATERING OF AQUEOUS SUSPENSIONS WITH ANIONIC AND CATIONIC POLYMERS

Title (en)

DEWATERING OF AQUEOUS SUSPENSIONS WITH ANIONIC AND CATIONIC POLYMERS

Title (de)

ENTWÄSSERUNG VON WÄSSRIGEN SUSPENSIONEN MIT ANIONISCHEN UND KATIONISCHEN POLYMERS

Title (fr)

DESHYDRATATION DE SUSPENSIONS AQUEUSES A L'AIDE DE POLYMERES ANIONIQUES ET CATIONIQUES

Publication

EP 1070021 A1 (EN)

Application

EP 99913490 A

Priority

  • GB 9900990 W
  • GB 9807046 A

Abstract (en)

[origin: WO9950188A1] A process for dewatering an aqueous suspension of solids which comprises adding to the suspension a flocculation aid, allowing the suspension to flocculate and dewatering the suspension, in which the flocculation aid is an aqueous composition comprising first and second water soluble ionic polymeric flocculants in which the first flocculant is in excess over the second flocculant and the first and second flocculants form particles of counterionic precipitate and substantially all of the proportion of the first flocculant which is not incorporated into the particles of counterionic precipitate is in solution, characterized in that the transfer and dosage conduits are constructed so that substantially none of the particles of counterionic precipitate are broken or dispersed after their formation and before their addition to the suspension.

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

C02F 1/56; B01D 21/01; C02F 11/14

IPC 8 full level (invention and additional information)

B01D 21/01 (2006.01)

CPC (invention and additional information)

B01D 21/01 (2013.01); B01D 21/2405 (2013.01); B01D 21/286 (2013.01)

Combination set (CPC)

B01D 21/01 + B01D 21/2405

Citation (search report)

See references of WO 9950188A1

Designated contracting state (EPC)

BE CH DE ES FR GB IE IT LI NL

EPO simple patent family

WO 9950188 A1 19991007; AU 3160399 A 19991018; AU 748307 B2 20020530; CA 2326355 A1 19991007; EP 1070021 A1 20010124; GB 9807046 D0 19980603; ZA 200005019 B 20011026

INPADOC legal status


2003-02-26 [18D] DEEMED TO BE WITHDRAWN

- Ref Legal Event Code: 18D

- Effective date: 20020823

2001-04-11 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20010221

2001-03-21 [RAP1] TRANSFER OF RIGHTS OF AN EP PUBLISHED APPLICATION

- Owner name: CIBA SPECIALTY CHEMICALS WATER TREATMENTS LIMITED

- Ref Legal Event Code: RAP1

2001-01-24 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000915

2001-01-24 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): BE CH DE ES FR GB IE IT LI NL