Expanding its innovative Integrated Compressor Line (ICL), GE Oil & Gas has introduced its first single-stage ICL, designed for low pressure ratio applications such as pipeline compression. Featuring 20% more operating range flexibility and greater efficiency, the new product was recently unveiled at the GE Oil & Gas 2013 Annual Meeting in Florence, Italy.
The single-stage ICL has a simplified design with only two magnetic bearings and no split parts and offers full access to critical components. With its very simple and robust architecture, the product costs about the same as a conventional BCL/PCL compressor, but has lower operating costs.
While the previously introduced ICL products are primarily designed for gas storage applications and feature multi-stages and multi-impellers, the new product is the first in the industry with only one impeller. This design enables high performance in applications where the requested design pressure ratio is very low (1.1:1.4), such as pipeline gas compression stations.
The impeller used in the single-stage ICL is from GE’s proven impeller family. Thanks to its customised shape, the impeller transmits the power from the motor to the gas by accelerating it. Then the static part at the outlet of the impeller transforms the speed of the gas into pressure. For a pressure ratio below 1.4, the optimised design of the single stage ICL enables very high efficiency and reduces the electrical power consumption compared to a multi-stage ICL or conventional centrifugal compressor.
The single-stage ICL is designed for gas boosting in a pipeline application. (Due to the length of the pipe, the gas pressure drops. In order to keep the gas transportation effective, after a certain distance the gas needs to be recompressed until the next station or its final destination.) The single-stage ICL has been optimised for this operation by minimising the electric power consumption. The use of state-of-the-art technology enables a very simple design using only one impeller, removing half of the bearings compared to a multi-stage ICL and improving both reliability and accessibility for maintenance.
The single-stage ICL offers all of the benefits of the other members of the ecomagination-qualified ICL family. Introduced in 2007, the ICL is an integrated system with a single casing for the compressor and the motor. Its technology saves energy and avoids at least 60% of associated CO2 emissions.
Designed to meet growing operational and environmental challenges faced by compression plant operators, ICL technology combines GE Oil & Gas compressor technology and GE Power Conversion motors and drive systems. It is an integrated system that utilises four proven technologies: centrifugal compression, active magnetic bearings, high speed electric motors and high frequency variable speed drive. These units do not require a gear box, lube oil system, shaft seals or external cooling system, which enables higher reliability and reduced maintenance time.
Using an average 8 MW CL rather than a comparable sized gas turbine-driven compressor can reduce CO2 emissions. Since the use of oil for the lubrication of bearings or other parts is not required, 30 000 l of oil are saved over the lifetime of an ICL compressor. The ICL’s electric motor also is much quieter than a conventional compressor and gas turbine drive.
The single-stage ICL offers a power range of 2 – 15 MW, design inlet pressure of 20 - 80 bar, discharge pressure up to 120 bar and maximum speed of 18 000 rpm. The new product is available globally, with the first commercial applications expected in the 2014 - 2015 time frame. Today, 16 ICL units are running and have accumulated more than 33 000 running hours and 1000 starts and stops for gas storage and pipeline operation in Europe.
The company’s Blue-C™ compressor, which is the first technology to take gas compression below the surface of the ocean, is currently in the finalising phase of the qualification tests and has accumulated more than 2300 running hours while installed in a pool. The compressor was built in a fully marinised version for the Ormen Lange Subsea Compression Station Project, executed by Aker Subsea for Statoil and Norske Shell, for deployment of the natural gas field. It is designed for unattended operation at over 2950 ft below sea level with power up to 12.5 MW. Installation on the seabed is expected in 2019.
Adapted from press release by Cecilia Rehn.