THE PRENFLO GASIFICATION PROCESS, DESIGN AND MATERIALS EXPERIENCE

The PRENFLO pressurised entrained-flow gasification process is now clo se to commercial application. A demonstration plant was operated in Fu rstenhausen, Germany for more than 10 000 hours and construction of th e first commercial 300 MWe IGCC plant is nearing completion in Spain. In this paper we will first provide a brief overview of the PRENFLO pr ocess and its major components, followed by a discussion of materials experience in the demonstration plant. Formal materials exposure progr ams were carried out in cooperation with EPRI and KEMA. Some results h ave been reported already, therefore we will concentrate here on new r esults. Overall conclusions on materials usage for the waste heat boil er section are: Carbon and low alloy steels are not suitable in the te mperature range of 320-570 degrees C. Most stainless steels have satis factory performance at evaporator temperatures, 320-450 degrees C. How ever at the high end of this temperature range stainless steels with a chromium content greater than 25% are preferred. Alloy 28 showed espe cially low corrosion rates. At superheater temperatures (>500 degrees C) most common stainless steels experience accelerated corrosion. Sili con containing alloys show improved performance in this temperature ra nge.