GE Gas Power in Italy recently announced completing an Axial Fuel Staging (AFS) technology upgrade on its 9E gas turbine at Raffineria di Milazzo (RaM) on the Sicilian coast and its Termica Milazzo combined heat and power plant located about 500 meters from the refinery.
This modernization was part of a broader project to extend the plant’s operational flexibility, achieve major integration, and decrease total emissions at turndown. Now, all electrical energy consumption of the Italian refinery (770 GWh in 2018) is supplied by the upgraded gas turbine.
“We needed a solution that would allow us to use more flexible power and steam for our industrial process at our site and GE’s 9E gas turbine upgrade at our Termica Milazzo site met all of our project expectations and requirements,” said Stafano Bertazzi, RaM ‘s Project Manager.
The new combustion system configuration increased the flexibility, efficiency, fuel savings and the overall sustainability of the refinery. In addition, by reducing load minimum turndown of the gas turbine, the refinery can add new revenue stream by its ability to sell additional power to the grid.
The combination of lowering operating costs and capturing new revenue streams can help the plant grow its profitability through more competitive operating profiles. It is now possible to modulate net exported energy production to participate in the Italian Balancing Services & Capacity Market, which enhance the economic benefits of the project.
Regarding emissions, by performing the AFS upgrade, the 9E plant now has a turndown of less than 40% of rated ISO nominal power — corresponding to a target of about 50-55% of the entire thermal combined-cycle plant output — which is dramatically lower than its previous 80% turndown level.
In addition, by derating exhaust mass flow at turndown, AFS also improves part-load gas turbine efficiency and reduces emissions — enabling an estimated savings of about 20% in CO2, CO and NOx site emissions.
The modernization of GE’s gas turbine was part of a broader project, including electrical and automation integration led by TERNA for Electrical Interconnecting work, while ABB supplied the plant Distributed Control System (DCS) and integrated it with the Substation Control System (SCS).
GE reports it has a large installed base of 9E gas turbines around the world, with approximately 650 units in Asia, China, Europe and the Middle East. The benefits achieved by the Italian Refinery can be replicated in these regions, making the refinery project a showcase for other power plant and industrial operators.