AMEC awards DCS contract for Scottish LNG project
23 Aug 2007
London -- AMEC Group Ltd has awarded Yokogawa UK Ltd a contract to supply an integrated distributed control and safety system for National Grid's LNG storage facility at Glenmavis, Scotland. The project includes the deconstruction of two liquefaction plants originally commissioned in 1973 and the construction of a new Black & Veatch Pritchard design liquefaction plant.
The liquefaction units were originally controlled by a Yokogawa Centum CS1000 DCS. This system has now been upgraded to the latest version of the DCS -- Centum CS3000 -- which forms the basis of the new integrated control and safeguarding system. The National Grid storage facility delivers on the basis of customer nominations, which are often 'within day', and involve re-gasification of LNG at rates of over 800 GWh per day.
According to Yokogawa, its control system enables National Grid to control the process plants within safe operating ranges and to initiate safety trips in the event of abnormal operation. The CS3000, it stated, achieves a reliability of 'seven nines' (99.99999%).
Yokogawa has extended the upgraded DCS to control the new liquefaction plant. The vendor has also integrated its ProSafe RS safety system for emergency shutdown (ESD) and gas detection logic plus a Plant Resource Management (PRM) system to form an integrated control and safeguarding system.
The upgraded DCS controls the many of the LNG storage process plants and provides an integrated view of all control functions, safety shutdown and gas detection. It also monitors field device diagnostics for HART-enabled field measurement instrumentation, generating on-line reports directly to operations and maintenance technicians via the DCS operator and maintenance display screens.
A further extension of the plant control system includes the control of new boil-off gas compressors and six new vaporisers. All these new plant areas have been incorporated into the integrated control and safeguarding system and share the same control room operator workstations.
