Major steam turbine control project in Qatar

Invensys has won a contract to supply four Triconex centrifugal pump steam turbine speed and overspeed control systems for use on the world's largest liquefied natural gas (LNG) project
Known as Qatargas II, this 9.5 billion Euro project involves expanding the LNG liquefaction plant at the Ras Laffan Industrial City in Qatar. This will further develop the large gas reserves in the country's North Field.

These are estimated to be in excess of 900 trillion cubic feet, or over 9% of the world's proven reserves.

The project also involves construction of two of the world's largest LNG trains.

When these come on line in late 2007 and early 2008, the project will process 30 billion m3pa of gas, 15.8 million tpa of LNG, 6 million tpa of condensates and 1.7 btpa of propane and butane.

The LNG will then be exported to a dedicated receiving terminal at Milford Haven in Wales on the west side of the UK.

The LNG will be carried by a new fleet of LNG carriers, currently under construction as part of a 1.3 billion Euro contract awarded to three South Korean shipyards.

Each of the four cabinet-based control systems supplied by Invensys is responsible for one turbine-driven boiler feed water pump on the new project.

The design, control and operation of these pumps is identical.

Each is based on the Triconex TS3000 turbomachinery control solution and includes communications modules to connect to a distributed control system (DCS) and Invensys Wonderware InTouch human machine interface (HMI).

Each cabinet includes Triconex technologies such as an Electronic Steam Turbine Governor System, a Speed System, Turbosentry Overspeed Protection, application software, and a panel-mounted PC with touch screen display for the Wonderware InTouch based HMI application.

In particular, the Triconex Electronic Steam Turbine Governor System comprises the Tricon version 10 main chassis and houses two 120V AC high density power modules, three main processors, Tricon Communication Modules, and the digital and analogue I/Os.

As well as benefitting from the integrated functionality and long experience of turbine system control brought by Invensys, this project will also benefit from the use of the company's Triple Modular Redundant (TMR) technology.

Triconex TMR technology employs three isolated, parallel control systems and extensive diagnostics integrated into one system.

It uses two-out-of-three voting to provide high-integrity, error-free, uninterrupted process operation.

The TMR architecture eliminates any single point of failure and enables on-line maintenance, on-line programming downloads, self-calibration and fault localisation.

The contract was awarded by GE Nuovo Pignone - on behalf of the main contractor, the Chiyoda Technip Joint Venture, for the Qatar Liquified Gas Company II (Qatargas II).

It is due for completion by August 2006.