(19)

(11)

EP 0 051 582 A1

(12)

(43) Date of publication: 19.05.1982 Bulletin 1982/20 (21) Application number: 80901126.0 (22) Date of filing: 22.05.1980

(51) International Patent Classification (IPC):  C02F 3/ 08( . ) (86) International application number: PCT/SE1980/000150 (87) International publication number: WO 1981/003325 (26.11.1981 Gazette 1981/28)

(84) Designated Contracting States: AT CH DE FR GB LI LU NL SE (71) Applicant: NORDISKA VATTENPROJEKT AB S-162 21 Vällingby (SE)	(72) Inventor: HALLEN, Lars-Ake S-162 29 Vällingby (SE)