Fuel Flexibility Critical For China Refinery: Fujian Petrochemical refinery utilizes two GE Frame 9E gas turbines
by robert m. jones
Robert M. Jones is manager – Syngas Power Island Products for GE Energy
In the changing global energy landscape, there is growing interest in the use of nontraditional fuels or alternative fuels, as power producers seek new and innovative ways to meet both their energy and environmental goals. Gas turbines with the flexibility to operate on a wide variety of fuels, including synthetic gas (syngas), are expected to play an increasingly important role in the energy industry of the future.
With its flexible fuel handling capabilities, GE’s Frame 9E gas turbine which has compiled more than 23 million hours of utility and industrial service worldwide can accommodate a broad spectrum of fuels including natural gas, light and heavy distlate oil, naphtha, crude, residual oil, blast furnace gas and biofuel. It can also burn a variety of syngases produced from oil or coal. Moreover, GE gas turbine technology provides for limited impact on the operation and maintenance of the gas turbine while burning alternative fuels.
A recent application highlighting the use of a Frame 9E operating successfully on syngas is the expansion of Fujian Petrochemical Co.’s (FPCL) refinery located in the Quangang District of Fujian Province, China. FPCL is owned by a joint venture composed of 50% Sinopec, 25% ExxonMobil and 25% Aramco. FPCL increased the refinery’s crude oil processing capacity from 4 million to 12 million tons per year. To support the increased power demands of that expansion, FPCL built an integrated gasification combined-cycle plant at the site. To reduce the pollutant waste from the refinery, FPCL selected two GE Frame 9E gas turbines for the IGCC plant capable of burning syngas made from refinery residues. Previously, the refinery waste gases were not recycled but were discharged into the atmosphere.
The Fujian system has dual-diluents (steam and N2) capability. The system provides FPCL with the flexibility to use steam, nitrogen or a blend to control the gas turbine emissions. The multinozzle quiet combustor (MNQC) and dual-diluent system are prepared to reduce emissions levels if future circumstances require lower emissions. Currently, the diluent system is not in operation, since the NOx level at the plant is between 170 to 190 mg/m3, which is within the existing environmental standards.
The IGCC plant includes two Frame 9E gas turbine-generator sets, and produces 260 MW of electricity and 280 tons of steam. All of the power, created from a previously wasted resource, is used to support refinery operations. Prior to the installation at the Fujian site, the flexibility of the combustors was validated in numerous tests at GE’s combustion lab in Greenville, South Carolina, U.S.A.
These tests explored the combustor’s operability and performance on liquid fuel, syngas fuel and in co-fire scenarios using both steam and nitrogen diluents. These tests were performed with hundreds of sensors to ensure the combustor durability across the expected operating regimes. As a final validation to ensure no shift in the lab vs. field performance, two instrumented combustors were installed in the gas turbine and monitored during commissioning.
Given the complexity of the project, GE assembled a global task force with people from the United States, India, China and France (the two gas turbines were manufactured and assembled at GE’s plant in Belfort, France). Following installation at the project site, the first 9E unit was originally fired on distillate oil in April 2009, was successfully synchronized to the grid using syngas in July 2009, and was turned over to the customer in December 2009.
The second unit was handed over in February 2010. Over the past year of operation, the plant has achieved 90% availability. Inspections have shown the durability of the gas turbine is meeting expectations. Huge gasifiers use heavy oil to produce a syngas mixture that requires a specific combustion system; in this case, GE’s MNQC technology was utilized. For Sinopec and the Chinese government, the Fujian expansion demonstrates the ability to build cleaner refineries, with reduced CO emissions, while still maintaining high levels of operability and productivity.
On a global basis, the project reinforces the concept that the use of alternative fuels, including process steam from industrial plants such as refineries, can generate added value. In a carbon-constrained environment, the technology trend is for combustion systems capable of burning syngas and hydrogen-rich fuels in combination with delivering the required operability.