Global Patent Index - EP 0842125 A1

EP 0842125 A1 19980520 - PROCESS FOR TREATING A SURPLUS ACTIVATED SLUDGE

Title (en)

PROCESS FOR TREATING A SURPLUS ACTIVATED SLUDGE

Title (de)

VERFAHREN ZUR BEHANDLUNG VON ÜBUSCHÜSSIGEN BELEBTSCHLAMM

Title (fr)

PROCEDE DE TRAITEMENT DE BOUES EXCEDENTAIRES ACTIVES

Publication

EP 0842125 A1 19980520 (EN)

Application

EP 96902522 A 19960212

Priority

  • RU 9600032 W 19960212
  • RU 95112218 A 19950718

Abstract (en)

[origin: WO9703928A1] The present invention relates to a process for treating settlings formed during the biological purification of municipal and industrial waste water and may be used in various fields of industry, in particular in paper and pulp production. A pre-thickened surplus activated sludge is subjected to treatment with white slime obtained at the state of causticizing green liquour in the sulfate-pulp production, while stirring. White slime is used in a volume ratio to the surplus activated sludge equal to 1 : 5 - 10. Thereupon, the sludge so treated is subjected to dehydration by filtering, preferably at a temperature of between 75 and 104 DEG C. The dehydrated settlings are dried and burned down. An ash residue so obtained as well as a clarified alkaline hydrolyzate are used in the manufacturing process of the sulfate-pulp production. The present process for treating the surplus activated sludge allows intensification of the filtration process, avoiding the use of expensive chemical reagents, a complete utilization of products obtained when treating the sludge as well as utilization of the sulfate-pulp production waste, that is white slime, with simplification of the production procedures and techniques and significant reduction of material costs.

IPC 1-7

C02F 11/12; D21C 11/00

IPC 8 full level

C02F 11/12 (2006.01); C02F 11/14 (2006.01); D21C 11/00 (2006.01); D21C 11/02 (2006.01); C02F 103/28 (2006.01)

CPC (source: EP KR)

C02F 11/121 (2013.01 - EP KR); C02F 11/14 (2013.01 - KR); C02F 11/143 (2018.12 - EP); C02F 11/145 (2018.12 - EP); D21C 11/0064 (2013.01 - EP KR)

Citation (search report)

See references of WO 9703928A1

Designated contracting state (EPC)

AT BE DE ES FR PT SE

DOCDB simple family (publication)

WO 9703928 A1 19970206; AU 4680296 A 19970218; BR 9609736 A 19991221; CA 2224683 A1 19970206; CN 1196033 A 19981014; EP 0842125 A1 19980520; FI 980091 A0 19980116; FI 980091 A 19980116; JP H11510090 A 19990907; KR 19990028251 A 19990415; NO 980210 D0 19980116; NO 980210 L 19980116; RU 2079454 C1 19970520

DOCDB simple family (application)

RU 9600032 W 19960212; AU 4680296 A 19960212; BR 9609736 A 19960212; CA 2224683 A 19960212; CN 96196796 A 19960212; EP 96902522 A 19960212; FI 980091 A 19980116; JP 50658797 A 19960212; KR 19970709562 A 19971220; NO 980210 A 19980116; RU 95112218 A 19950718