Dual Fuel Conversion Project Complete (West Springfield)
Submitted by David Forbes, Director, Waldron Construction LLC
Just three months after construction began on the dual fuel conversion of two LM6000 gas turbines, the power plant is commercially operational on both fuels.
In August, Con Edison Development brought Waldron Construction on board to execute a turnkey design-build project to convert two 40MW LM6000's at their West Springfield, MA plant to fire no. 2 oil as well as natural gas. Waldron Construction and Waldron Engineering were released to start the project in late August and after 6 weeks of engineering, design and procurement, construction began in early October. Two rainy months of construction later the turbines, which had remained operational up to this time, were shut down for both “in package” and SCR modifications. By December 31st Waldron had completed all modifications and commissioning, and both units were ready for service.
The scope of work included: obtaining a permit from the State Fire Marshalís office, demolition and site prep while working around two large buried high pressure gas mains, installing a remotely controlled truck gate, constructing a spill containing covered unloading station capable of handling two tractor trailers simultaneously with a dry chemical fire suppression system, installing 5 double walled tanks with a total capacity of 100,000 gallons, building a lined containment basin for the tanks, and erecting a pump house building containing the transfer and forwarding pumps, fuel oil heater, transformer and miscellaneous electrical panels.
The piping work which was part carbon steel and part stainless included: the unloading system, storage and recirculation system, forwarding supply and return system to the turbines in the main power house about 500 feet away, high pressure fuel oil booster systems, and high pressure water injection and drain system. All exterior piping was heat traced and insulated.
Various other pieces of equipment included an oily water separator, a two stage duplex fuel oil filter, fuel oil booster skids, high pressure water injection skids, ammonia flow control and heater skids, and opacity monitors.
The electrical work included: modifications to two unit sub stations and MCC's in the power house, grounding, lightning protection, lighting at the pump house, unloading area and storage tanks, and powering all pumps and heaters.
Instrumentation and control work through an existing Delta V HMI tied to GE's Mark VI, a CEMS PLC and the SCR PLC systems included: tank monitoring and level control, fuel oil temperature control, fuel oil flow and pressure monitoring and control, motor starting and control, fire alarm and suppression system monitoring and control, injection water flow and pressure monitoring and control, opacity monitor installation and new screen generation and integration.
During the shutdown all the ammonia injection lances in both exhaust ducts were removed and replaced, both ammonia flow control and heater skids were replaced and had power and control wiring modifications, the ammonia injection orifice plates were changed out in all manifolds, the high pressure water injection skids were piped and wired up, fuel oil booster piping was installed to the turbine packages and modifications were done internally to the turbine packages.
The plant now operates on both fuels meeting emissions and performance goals.