Global patent index - EP 1028918 A1

EP 1028918 A1 2000-08-23 - APPARATUS FOR DEWATERING PREVIOUSLY-DEWATERED MUNICIPAL WASTE-WATER SLUDGES USING HIGH ELECTRICAL VOLTAGE

Title (en)

APPARATUS FOR DEWATERING PREVIOUSLY-DEWATERED MUNICIPAL WASTE-WATER SLUDGES USING HIGH ELECTRICAL VOLTAGE

Title (de)

METHODE UND VORRICHTUNG ZUR ENTWÄSSERUNG VON VORENTWÄSSERTEN KOMMUNALEN ABWASSERSCHLÄMMEN MITTELS HOCHSPANNUNG

Title (fr)

APPAREIL SERVANT A DESHYDRATER LES BOUES D'EAUX USEES MUNICIPALES PREALABLEMENT DESHYDRATEES A L'AIDE DE DECHARGES ELECTRIQUES A HAUTE TENSION

Publication

EP 1028918 A1 (EN)

Application

EP 97946649 A

Priority

US 9720631 W

Abstract (en)

[origin: CA2307724A1] The present invention is directed to a pulsed electric-field system, apparat us and method for the effective disinfecting and dewatering previously-dewatere d, biologically active waste-water sludges (e.g., municipal waste-water sludge) in an efficient manner, so as to dramatically reduce the resulting volume of the inert waste material which has to be disposed of by the municipality. Th e method employed sequentially consists of hydraulically pressurizing (24, 26) the previously dewatered sludge, pre-heating (32) the previously dewatered sludge to a predetermined temperature range, exposing the previously dewater ed sludge to high energy pulsing electrical discharges (42), pressure separatio n (52) of the resulting solids and liquid fraction, and final pressure extrusi on (70) of the separated solids through nozzles.

[origin: CA2307724A1] The present invention is directed to a pulsed electric-field system, apparatus and method for the effective disinfecting and dewatering previously-dewatered, biologically active waste-water sludges (e.g., municipal waste-water sludge) in an efficient manner, so as to dramatically reduce the resulting volume of the inert waste material which has to be disposed of by the municipality. The method employed sequentially consists of hydraulically pressurizing (24, 26) the previously dewatered sludge, pre-heating (32) the previously dewatered sludge to a predetermined temperature range, exposing the previously dewatered sludge to high energy pulsing electrical discharges (42), pressure separation (52) of the resulting solids and liquid fraction, and final pressure extrusion (70) of the separated solids through nozzles.

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

C02F 11/12; C02F 1/48

IPC 8 full level (invention and additional information)

C02F 11/12 (2006.01); C02F 1/48 (2006.01)

Citation (search report)

See references of WO 9924372A1

Designated contracting state (EPC)

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

EPO simple patent family

AU 5177698 A 19990531; CA 2307724 A1 19990520; CA 2307724 C 20030318; EP 1028918 A1 20000823; JP 2001522721 A 20011120

INPADOC legal status

2005-03-02 [18W] WITHDRAWN

- Ref Legal Event Code: 18W

- Effective date: 20050107

2003-05-21 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20030404

2000-09-20 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000602

2000-08-23 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE