TWO NEW GAS TURBINES FOR OIL & GAS

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GE OIL & GAS CHOSE ITS ANNUAL MEETING TO ANNOUNCE ITS LATEST TURBOMACHINERY OFFERINGS, THE NOVALT12 AND THE LM9000

NovaLT12

New gas turbines are a relatively rare event. You may not get more than one or two in a typical year. But to have two announced at the start of the year at one show?

Yet that is exactly what happened to kick off 2017. Even more surprising was the fact that GE had given no indication that these machines were in the works. Yet right at the start of the GE Oil & Gas Annual Meeting (AM) in Florence (p. 16) in January of 2017, the company announced its latest turbomachinery offerings, the NovaLT12 and the LM9000.

NovaLT12

About two years ago, the company unveiled the NovaLT16 gas turbine, aimed primarily at the oil and gas market. Ten of these 16 MW machines are now being assembled in the GE Oil & Gas factory in Florence, Italy.

Rod Christie, President & CEO for Turbomachinery Solutions (p. 32), said that the company can deliver a unit within six months of an order being placed. “We have just developed a new combustor for the NovLT16 which brings NOx emissions down from 25 ppm to 15 ppm,” he said. GE followed the NovaLT16 last year with the NovaLT5. Nine of these 5 MW machines are now being manufactured.

At the Annual Meeting, the company unveiled the NovaLT12 as the third product of this new line. The standard model delivers 12.6 MW. But there will be future design options for power requirements from 10.5 MW to 13.9 MW.

This turbine has been designed to have higher efficiency and lower total cost of ownership than market peers, said Christie, and provides over 80% efficiency in cogeneration applications. But it will have a focus on oil and gas midstream operations — both mechanical drive and power generation.

Christie added that it would do well in various upstream and downstream applications. This includes its use as a generator drive in industrial power generation, combined heat & power (CHP), offshore power generation and mechanical drive (pipeline). Industrial applications are likely to include pulp & paper, cement, chemical, petrochemical, steel, biogas and district heating.

Due to standardization of design and modularization features, the company is advertising 36 weeks from order placement to delivery and an 8-week installation. The turbine’s fuel burners are manufactured using 3D printing technology at GE Oil & Gas’ additive manufacturing facility in Talamona, Northern Italy, which began production in 2016.

“Additive manufacturing (AM), together with automated manufacturing techniques, allows us to develop parts and products more efficiently, with better performances and more cost-effectively; this accelerates the speed at which we can bring product to market,” said Christie. “Compared to traditional production techniques, AM offers the possibility to realize any form in a single piece without having to join pieces.”

The improvements are significant from the point of view of the characteristics of the base materials: Production by successive layers offers detailed control of the structure as well as the homogeneity of the part. Production times are also reduced. The finished product can be obtained in weeks instead of months. In addition, additive manufacturing enables the company to optimize the design of gas turbine combustion components to suit tailored requirements, such as low emissions for NOx and CO2.

GE LM9000 gas turbine

LM9000

This two-shaft 65 MW aeroderivative machine will have 43% simple cycle efficiency, higher than any other GE aeroderivative. Its name was derived from the GE90 jet engine fitted on the Boeing 777. The GE90-115B, said to be the largest and most powerful jet engine in the world, produces 127,900 pounds of thrust.

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“The introductory power for the LM9000 is 65 MW, but we have a roadmap to reach much higher,” said Christie.

This follows on from a long line of LM engines. The LM100 was developed from a helicopter engine in the late 1950s. The LM1500 added supersonic engine components from the J79, generating more than 10 MW.

Since then, aeroderivatives, such as the LM2500, LM5000 and LM6000 have emerged as well as the hybrid LMS100. The LM9000 continues the tradition. It was developed to power massive liquefied natural gas (LNG) plants. For offshore and onshore LNG applications, a big selling point is its promise of over 99% availability in mechanical drive.

Another selling point is torque. It has enough power and starting torque that LNG plant operators can restart production immediately without first draining the refrigerant from the entire plant.

“With other compressors, you must empty them of refrigerant as they don’t have high enough torque to start,” said Christie. “The LM9000’s higher torque avoids compressor leakage if you have no need to drain and vent.”

Free-power architecture It also comes without a gearbox. Its free-power turbine architecture enables the machine to operate over a wide range of power and speed conditions while maintaining high efficiency.

“The LM9000 will provide the highest availability with the lowest cost of ownership for LNG applications,” said Christie. “It could help LNG plants lower production costs by 20%.”

The LM9000 is said to deliver a 50% longer maintenance interval, 20% more power and 40% lower NOx emissions compared to the machines it competes with. GE believes its LM6000PF+ is already competitive in this segment.

This new edition to the LM6000 family just fired up in January and is undergoing testing in Italy. Christie said it will ship by the end of summer and is destined for an LNG train.

“We are at the end of what we can do with the LM6000 line in terms of power output,” said Christie. “But we believe we can take the LM9000 even further.”

As well as LNG and oil & gas, the LM9000 can be used for simple cycle, cogeneration and combined cycle power generation. In CHP, for example, it offers over 80% efficiency. A Dry Low Emissions (DLE) combustor, developed, using GE’s AM capabilities, enables dual-fuel capability and lower NOx emissions, while eliminating water use in emissions abatement.

The LM9000’s dual-fuel design is based on the DLE1.5 used in the LM2500 and LM6000 product families. It allows for lower NOx emissions without the need for water injection, with both gas and liquid fuel. The engine is capable of online fuel transfer from gas to liquid to gas without interruption in operation. This dry low emissions technology can help meet stringent emissions norms and simplify the amount of balance of plant equipment that is required. For example, it eliminates the need for a demineralized water system and associated equipment.

On the maintenance front, it requires a one-day hot section change out at 36,000 hours and a major maintenance interval at 72,000 hours. That adds up to less than three days of outage time in 72,000 hours. In comparison, a heavy-duty 6FA gas turbine would need up to 58 days of outage in that same period. While there is ample LNG and oil & gas potential for the LM9000,

Christie said some customers are interested in using it for power. Envisioned markets for simple cycle applications can include its use in conjunction with renewables due to its fast-start capabilities, such as offshore wind. Although it is suitable for CHP applications, it may not play so well in combined cycle plants.

Christie said it provides flexibility in the steam cycle without losing core efficiency. However, it will not be able to match heavy duty gas turbine efficiency levels in combined cycle.

“As the LM9000 gets high efficiency out of the core engine, we are less interested in driving complete combined cycle efficiency,” he said. “It also has a lower exhaust temperature than an industrial engine.” The first LM9000 is slated to enter service in mid 2019.