(19)

(11)

EP 0 812 409 A1

(12)

(43) Date of publication: 17.12.1997 Bulletin 1997/51 (21) Application number: 96902387.0 (22) Date of filing: 14.02.1996

(51) International Patent Classification (IPC):  F23N 1/ 02( . ) F23N 5/ 00( . ) F23N 5/ 24( . ) F23N 3/ 08( . ) F23N 5/ 18( . ) (86) International application number: PCT/GB1996/000348 (87) International publication number: WO 1996/025629 (22.08.1996 Gazette 1996/38)

(84) Designated Contracting States: BE DE ES FR GB IT NL SE (30) Priority: 16.02.1995 GB 19950003065 27.11.1995 GB 19950025197 (71) Applicant: BG plc Reading, Berkshire RG6 1PT (GB)	(72) Inventor: SUTTON, David, Michael Surrey GU15 3EG (GB) (74) Representative: Morgan, David James  British Gas plc, Intellectual Property Department, 100 Thames Valley Park Drive Reading, Berkshire RG6 1PT Reading, Berkshire RG6 1PT (GB)