Gas Turbine Handbook : Principles and Practices

Case Study #1 235
lockhoppers. The syngas is transferred to a hot gas conditioning
system for removal of sulfur compounds, particulates and other
contaminants to meet environmental and combustion turbine fuel
requirements. The power island includes a GE model MS6001FA
combustion turbine capable of operating on natural gas, syngas or
propane and a heat recovery steam generator (HRSG). Superheated,
high pressure steam generated in the HRSG and the gasification
and desulfurization sections supplies the steam turbine.
Description of Major Components
Key equipment items and systems which will be part of
the unique technology of the Piñon Pine Power Project are the
pressurized (20 bars) KRW gasifier with in-bed desulfurization,
primary cyclone, external regenerable sulfur removal, fine particulate
filters, and some aspects of the gas turbine. Advanced KRW
gasification technology produces a low-Btu gas (heating value approximately
130 Btu/SCF [4838KJ/m 3 ]) which is used as fuel in
the combined-cycle power plant, and includes hot gas removal of
particulates and sulfur compounds from the fuel gas, resulting in
low atmospheric emissions. Desulfurization will be accomplished
by a combination of limestone fed to the gasifier and treatment of
the gas in desulfurization vessels using a zinc-based sulfur sorbent
such as Phillips proprietary Z-Sorb III ® . Particulates will be
removed by a pair of high-efficiency cyclones and a barrier filter.
These operations will be carried out at the elevated temperature
of approximately 1000°F [538°C] to eliminate the thermodynamic
inefficiency and capital cost of cooling and cleaning the gas at low
temperature, which is associated with other IGCC systems. Since
water vapor is not condensed in the hot gas clean-up process, water
effluents will be reduced and will consist of only feed water
treatment effluent and boiler and cooling tower blow down.
Sub-bituminous coal will be received at the plant from a unit
train consisting of approximately 84 railcars of between 100- and
110-ton capacity, arriving approximately once a week. In addition,
the project will also demonstrate the ability to operate on
higher sulfur, eastern coals. Currently, Southern Pacific Railroad
facilities are on site; the railroad line is a main east-west supply
route. Upgrading and extending the spur on SPPCo. land will be
required for the proposed project. Coal will be received at an en-