Work is presented on the development of a coal-fired high performance power generation system by the year 2000. This report describes the design of the air heater, duct heater, system controls, slag viscosity, and design of a quench zone.

In Phase 1 of the project, a conceptual design of a coal-fired, high-performance power system (HIPPS) was developed, and small-scale R and D was done in critical areas of the design. The current phase of the project includes development through the pilot plant stage and design of a prototype plant that would be built in Phase 3. The power-generating system being developed in this project will be an improvement over current coal-fired systems. It is a combined-cycle plant. This arrangement is referred to as the All Coal HIPPS because it does not require any other fuels for normal operation. A fluidized bed, air-blown pyrolyzer converts coal into fuel gas and char. The char is fired in a high-temperature advanced furnace (HITAF) which heats both air for a gas turbine and steam for a steam turbine. The fuel gas from the pyrolyzer goes to a topping combustor where it is used to raise the air entering the gas turbine to 1288 C. In addition to the HITAF, steam duty is achieved with a heat-recovery steam generator (HRSG) in the gas turbine exhaust stream and economizers in the HITAF flue gas exhaust stream. Progress during the quarter is described.

In Phase 1 of the project, a conceptual design of a coal-fired high performance power system was developed, and small scale R and D was done in critical areas of design. The current Phase of the project includes development through the pilot plant stage, and design of a prototype plant that would be built in Phase 3. The power generating system being developed in this project will be an improvement over current coal-fired systems. Goals have been identified that relate to the efficiency, emissions, costs and general operation of the system. These goals are: Total station efficiency of at least 47 percent on a higher heating value basis; emissions: NO(subscript x)

A High Performance Power System (HIPPS) is being developed. This system is a coal-fired, combined cycle plant with indirect heating of gas turbine air. Foster Wheeler Development Corporation and a team consisting of Foster Wheeler Energy Corporation, AlliedSignal Aerospace Equipment Systems, Bechtel Corporation, University of Tennessee Space Institute and Westinghouse Electric Corporation are developing this system. In Phase I of the project, a conceptual design of a commercial plant was developed. Technical and economic analyses indicated that the plant would meet the goals of the project which include a 47 percent efficiency (HHV) and a 10 percent lower cost of electricity than an equivalent size PC plant. The concept uses a pyrolyzation process to convert coal into fuel gas and char. The char is fired in a High Temperature Advanced Furnace (HITAF). It is a pulverized fuel-fired boiler/airheater where steam and gas turbine air are indirectly heated. The fuel gas generated in the pyrolyzer is then used to heat the gas turbine air further before it enters the gas turbine. The project is currently in Phase 2 which includes engineering analysis, laboratory testing and pilot plant testing. Research and development is being done on the HIPPS systems that are not commercial or being developed on other projects. Pilot plant testing of the pyrolyzer subsystem and the char combustion subsystem are being done separately, and then a pilot plant with integrated pyrolyzer and char combustion systems will be tested. In this report, progress in the pyrolyzer pilot plant preparation is reported. The results of extensive laboratory and bench scale testing of representative char are also reported. Preliminary results of combustion modeling of the char combustion system are included. There are also discussions of the auxiliary systems that are planned for the char combustion system pilot plant and the status of the integrated system pilot plant.

In phase 1 of the project, a conceptual design of a coal-fired high performance power system was developed, and small scale R & D was done in critical areas of the design. The current Phase of the project includes development through the pilot plant stage, and design of a prototype plant that would be built in Phase 3. Goals have been identified that relate to the efficiency, emissions, costs and general operation of the system. The base case arrangement of the HIPPS cycle is shown in Figure 1. It is a combined cycle plant. This arrangement is referred to as the All Coal HIPPS because it does not require any other fuels for normal operation. A fluidized bed, air blown pyrolyzer converts coal into fuel gas and char. The char is fired in a high temperature advanced furnace (HITAF) which heats both air for a gas turbine and steam for a steam turbine. The air is heated up to 1400F in the HITAF, and the tube banks for heating air are constructed of alloy tubes. The fuel gas from the pyrolyzer goes to a topping combustor where it is used to raise the air entering the gas turbine to 2350F. In addition in the HITAF, steam duty is achieved with a heat recovery steam generator in the gas turbine exhaust stream and economizers in the HITAF flue gas exhaust stream. An alternative HIPPS cycle is shown in Figure 2. This arrangement uses a ceramic air heater to heat the air to temperatures above what can be achieved with alloy tubes. This arrangement is referred as the 35% natural gas HIPPS. A pyrolyzer is used as in the base case HIPPS, but the fuel gas generated is fired upstream of the ceramic air heater instead of in the topping combustor. Gas turbine air is heated to 1400 F in alloy tubes the same as in the All Coal HIPPS. This air then goes to the ceramic air heater where it is heated further before going to the topping combustor. The temperature of the air leaving the ceramic air heater will depend on technological developments in that component.