Partial Oxidation Gas Turbine for Power and Hydrogen Co-Production from Coal-Derived Fuel in Industrial Applications (2009)

The report presents a feasibility study of a new type of gas turbine. A partial oxidation gas turbine (POGT) shows potential for really high efficiency power generation and ultra low emissions. There are two main features that distinguish a POGT from a conventional gas turbine. These are associated with the design arrangement and the thermodynamic processes used in operation. A primary design difference of the POGT is utilization of a non?catalytic partial oxidation reactor (POR) in place of a conventional combustor. Another important distinction is that a much smaller compressor is required, one that typically supplies less than half of the air flow required in a conventional gas turbine. From an operational and thermodynamic point of view a key distinguishing feature is that the working fluid, fuel gas provided by the OR, has a much higher specific heat than lean combustion products and more energy per unit mass of fluid can be extracted by the POGT expander than in the conventional systems. The POGT exhaust stream contains unreacted fuel that can be combusted in different bottoming ycle or used as syngas for hydrogen or other chemicals production. POGT studies include feasibility design for conversion a conventional turbine to POGT duty, and system analyses of POGT based units for production of power solely, and combined production of power and yngas/hydrogen for different applications. Retrofit design study was completed for three engines, SGT 800, SGT 400, and SGT 100, and includes: replacing the combustor with the POR, compressor downsizing for about 50% design flow rate, generator replacement with 60 90% ower output increase, and overall unit integration, and extensive testing. POGT performances for four turbines with power output up to 350 MW in POGT mode were calculated. With a POGT as the topping cycle for power generation systems, the power output from the POGT ould be increased up to 90% compared to conventional engine keeping hot section temperatures, pressures, and volumetric flows practically identical. In POGT mode, the turbine specific power (turbine net power per lb mass flow from expander exhaust) is twice the value of the onventional turbine. POGT based IGCC plant conceptual design was developed and major components have been identified. Fuel flexible fluid bed gasifier, and novel POGT unit are the key components of the 100 MW IGCC plant for co producing electricity, hydrogen and/or yngas. Plant performances were calculated for bituminous coal and oxygen blown versions. Various POGT based, natural gas fueled systems for production of electricity only, coproduction of electricity and hydrogen, and co production of electricity and syngas for gas to liquid and hemical processes were developed and evaluated. Performance calculations for several versions of these systems were conducted. 64.6 % LHV efficiency for fuel to electricity in combined cycle was achieved. Such a high efficiency arise from using of syngas from POGT exhaust s a fuel that can provide required temperature level for superheated steam generation in HRSG, as well as combustion air preheating. Studies of POGT materials and combustion instabilities in POR were conducted and results reported. Preliminary market assessment was performed, and recommendations for POGT systems applications in oil industry were defined. POGT technology is ready to proceed to the engineering prototype stage, which is recommended.