With high reliability and availability minimizing plant downtimes, and the ability to operate on a wide variety of fuels, power is available when you require it.

Fuel flexibility is our strength

While traditionally operated on natural gas, Siemens’ gas turbines are able to operate on a wide range of gas or liquid fuels, using either conventional combustion technologies, or the robust Dry Low Emissions (DLE) technologies to ensure minimum environmental impact.

If no natural gas infrastructure is available, the gas turbines could utilize the associated gases from oil production, or on some models even bi-fuel – operate on a mixture of gas and liquid fuels simultaneously if insufficient gas is available to fully fuel the turbine.

SGT-800: High efficiency, high availability

The SGT-800 gas turbine was designed to maximize energy efficiency and minimize downtime in Cogeneration applications. While the SGT-800 can be overhauled on site, the core exchange maintenance concept reduces scheduled downtime to less than 60 days over 17 years. With an electrical power output of 47 or 50.5 MW, the SGT-800 can produce, unfired, in excess of 85 tonnes/hour of dry saturated steam at 66 bara pressure, an overall energy efficiency of over 80%. By firing to 925°C, over 185 tonnes/hour of steam at the same conditions can be produced, a similar volume to that from a 85MW class heavy duty gas turbine, while increasing the overall energy efficiency of the cogeneration plant to over 91%.

SGT-500: Heavy Fuel Oil Capability

For over 50 years this gas turbine has served the oil & gas and power industries, delivering power with outstanding operational reliability both onshore and offshore. The SGT-500 is unique within the Siemens portfolio in its ability to operate on non-premium liquid fuels, including relatively viscous fuels such as heavy fuel oil (HFO), or even potentially treated crude oils as low as 13° API gravity, refinery residual oils and bio-oils.

The burner design is able to accept liquid fuels with viscosities up to 20cSt, more than twice the permissible viscosity of most gas turbines. Combined with the pressurized fuel system that allows the fuel to be pre-heated to as high as 150°C to reduce the fuel viscosity, it is possible to use fuels with viscosities of 750cSt at 50°C or higher in the SGT-500. This allows the operator to use common heavy fuel oils such as IM380, as well as crude oils and residual oils from refining processes. Where it is necessary to comply with strict environmental regulations, water injection can be used to reduce NO_X emissions. Depending on the carbon residue value of the fuel, it is possible to achieve NO_X emissions below 50 ppm across the whole load range. The SGT-500 also has the ability to bi-fuel – to operate on a mixture of both gas and liquid fuels. This feature reduces the need to flare associated gas, or allows the gas to be used for other process purposes, such as gas lift.

Its low firing temperature contributes to an impressive maintenance program, with an expected 80,000 hours between major overhauls, 10,000 hours of operation between inspections and with a core exchange program, potentially just 24 days downtime in 10 years – that is an availability of more than 97%.

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Heat recovery increases operational economy

This concept, known as Cogeneration or Combined Heat & Power (CHP), maximizes the energy efficiency of a facility, offering overall fuel efficiencies of over 90%. It provides the electricity needed for the production or refining process and at the same time produces almost all the steam required.

Increasingly, thermal recovery techniques, such as Cyclic Steam Injection (CSS) or Steam Assisted Gravity Drainage (SAGD), are being employed to maximize oil recoveries, e.g., in Heavy Oil production. The waste heat in the exhaust of a gas turbine can be recovered and used to produce the steam required for injection, or to heat other fluids that may be used in the operations. The high proportion of oxygen in the exhaust gases of a gas turbine offer the option to install a duct burner to boost steam production to even higher levels.

Using steam turbines to optimize efficiency

Steam turbines can also be used for Cogeneration plants: by increasing the pressure at which the steam is generated in the boiler plant, a back-pressure steam turbine can be installed generating a large percentage of, and potentially all, the power required for operations, while still allowing steam to be distributed around the oilfield at a sufficiently high pressure to minimize condensate production. Siemens’ range of steam turbines is capable of operating on saturated steam, removing the need for superheaters and expensive boiler plant.

Innovative solutions using steam turbines

At the remote wellpads, Siemens’ mini steam turbines SST-040 can be used in place of pressure reduction valves, reducing steam pressure from distribution pressures down to the pressures required for injection, and generating the power required for pumps and instrumentation, potentially allowing the wellpad to operate independently from the central power plant.

Waste heat from upgrading and refining processes can be used to produce steam for additional power generation, or to drive a steam turbine for pumping or compression duties. Such concepts minimize reliance on external power supplies, making the best use of locally produced heat energy. This way energy costs and CO₂ emissions can be reduced.

With all these intercompatible, proven products globally available, Siemens Energy Oil & Gas can provide the optimum energy solution for your oil and gas operations.