MAN Diesel has retrofitted duel fuel technology to a stationary V-12 engine used in an industrial cogen application in Portugal.
In over 11 years of operation the 48/60 engine had logged over 88,000 hours in grid parallel baseload mode at the cogeneration plant, where its thermal output is used to raise process steam for a textile works. Têxtil Manuel Gonçalves, Sociedade de Producao de Electricidade e Calor S.A. (TMG SPE) runs the textile works in the town of Vila Nova de Famalicão.
In its first such retrofit on an existing heavy fuel engine, MAN has converted the plant to full 51/60DF specification, which will allow the facility to run on natural gas.
As well as exchange of the original cylinder liners and pistons of 480 mm diameter to new 510 mm bore components, other major changes were new piston crowns with piston bowls adapted to gas combustion, new cylinder heads with pilot injectors and gas admission valves (in the inlet ports), new inlet cams and the common rail pilot injection pumps, pressure accumulators and solenoid valve system.
The conversion also included turbocharger rematching for gas engine operation via the fitting of new nozzle rings and further adaptation of the exhaust system. The converted engine has also been equipped with a new safety and control system.
Manfred Gallersdörfer, leader of the 51/60DF retrofit team at PrimeServ, which handles all engine and turbocharger upgrades for MAN Diesel, explained that since the 51/60DF dual-fuel engine is based on MAN Diesel’s 48/60 medium speed engine platform – and since a major overhaul was due – TMG SPE decided it was a good opportunity to convert to dual-fuel gas operation.