Operating experience and improvement opportunities for coal-based IGCC plants

Abstract

The four major coal-based IGCC plants, each of 250–300 MW, commissioned in the 1990s have now either entered or are about to enter full commercial service. These pioneer plants, two in the US (Tampa and Wabash), two in Europe (Buggenum and Puertollano) experienced the usual spate of problems during their initial two or three years of operation. However, these plants are now running at much improved availabilities similar to those of many other solid fueled plants. Furthermore the lessons learned from these pioneer plants suggest several areas where materials development could further improve the availability of IGCC plants as currently commercially offered. Even without the likelihood of carbon emissions related regulation, coal based IGCC technology is very close to being economically competitive with pulverized coal-fired (PC) plants and can meet extremely stringent environmental emission standards. IGCC is already commercially cost competitive in many worldwide locations when using petroleum residual feedstock. Moreover as a technology that has only recently moved to the commercial marketplace there is a very considerable upside potential for improvements in all the key components of IGCC technology over the next decades.Air separation units (ion transfer membranes (ITMs) or other new membranes)Gasification (feed systems, refractories, injectors)Gas cooling (higher temperature metals)Gas cleaning (S, N and trace elements – new sorbents)Separation of gas species (membranes CO2 and H2)Gas turbine advances (high-temperature materials, coatings)Advanced cycles (humid air turbine (HAT), O2/CO2, hybrids)Fuel cell cycles (lower cost materials, manifolds)These future advances will depend on the development of new materials and designs, which if successful should provide better environmental and process performance, higher efficiency and reduced capital and life cycle costs.