(19)

(11)

EP 0 051 623 A1

(12)

(43) Date of publication: 19.05.1982 Bulletin 1982/20 (21) Application number: 81901210.0 (22) Date of filing: 12.05.1981

(51) International Patent Classification (IPC):  C10L 5/ 00( . ) B03D 3/ 06( . ) B03B 9/ 00( . ) C10L 9/ 00( . ) (86) International application number: PCT/AU1981/000055 (87) International publication number: WO 1981/003337 (26.11.1981 Gazette 1981/28)

(84) Designated Contracting States: AT CH DE FR GB LI LU NL SE (30) Priority: 13.05.1980 AU 19800003515 (71) Applicants: BP AUSTRALIA LIMITED Melbourne Victoria 3000 (AU) THE BROKEN HILL PROPRIETARY COMPANY LIMITED Melbourne, Victoria 3000 (AU)	(72) Inventors: MAINWARING, David E. Melbourne, Vic. 3000 (AU) JONES, Charles U. Melbourne, Vic. 3000 (AU) (74) Representative: Pennant, Pyers, et al  Stevens, Hewlett & Perkins 1 Serjeants' Inn Fleet Street London EC4Y 1LL London EC4Y 1LL (GB)