Global Patent Index - EP 1257506 A1

EP 1257506 A1 2002-11-20 - METHOD FOR REDUCING SPECIFIC RESISTANCE TO FILTRATION OF BIOLOGICAL SLUDGE DERIVED FROM A WASTE WATER PURIFYING STATION

Title (en)

METHOD FOR REDUCING SPECIFIC RESISTANCE TO FILTRATION OF BIOLOGICAL SLUDGE DERIVED FROM A WASTE WATER PURIFYING STATION

Title (de)

VERFAHREN ZUR VERMINDERUNG DES SPEZIFISCHEN FILTRATIONSWIDERSTANDS EINES KLÄRSCHLAMMS

Title (fr)

PROCEDE POUR ABAISSER LA RESISTANCE SPECIFIQUE A LA FILTRATION DE BOUES BIOLOGIQUES PROVENANT D'UNE STATION D'EPURATION D'EAUX USEES

Publication

EP 1257506 A1 (FR)

Application

EP 01907844 A

Priority

  • FR 0100487 W
  • FR 0002188 A

Abstract (en)

[origin: WO0162679A1] The invention concerns a method for reducing specific resistance to filtration of biological sludge to facilitate the separation of the solid phase and the aqueous phase by mechanical filtering, in particular in a filter press enabling to obtain a compacted cake with specific dry solid content. Said method is characterised in that, prior to mechanical filtering, it consists in adding to the biological sludge mineral particles containing hydrophobic species of magnesium silicate, and hydrophilic species of magnesium and aluminium silicate and/or magnesium and/or calcium carbonate in predetermined relative proportions ranging between 20/80 and 80/20, said particles having a predetermined mean diameter D50 ranging between 3 and 30 microns. The inventive method leads to significant reduction of specific resistance to biological sludge filtering.

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

C02F 11/14

IPC 8 full level (invention and additional information)

B01D 33/052 (2006.01); C02F 11/14 (2006.01)

CPC (invention and additional information)

C02F 11/14 (2013.01)

Citation (search report)

See references of WO 0162679A1

Designated contracting state (EPC)

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

EPO simple patent family

WO 0162679 A1 20010830; EP 1257506 A1 20021120; FR 2805180 A1 20010824; FR 2805180 B1 20020913

INPADOC legal status


2006-03-15 [18D] APPLICATION DEEMED TO BE WITHDRAWN

- Effective date: 20050901

2002-11-20 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20020809

2002-11-20 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

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