Rapid steam generators for Europe’s largest LNG terminal

Process heating systems specialist Babcock Wanson has completed a project for National Grid featuring two bespoke Rapid Steam Generators at its Grain LNG importation terminal in Rochester, Kent, UK.

Grain LNG is of strategic national importance to the UK’s energy infrastructure and security of supply. It is the largest terminal in Europe and eighth largest in the world by tank capacity (1,000,000m3) with a site that spans over 600 acres in total.



Following a major project to substantially increase the LNG handling capacity at Grain LNG, which has seen new storage tanks installed with four times the capacity of each of the originals, it was decided to upgrade the process heating system that converts the LNG to a gaseous state.

Working closely with National Grid, Babcock Wanson has designed a sophisticated steam generation system based on two of its 7000kg/h VPX Rapid Steam Generator to replace the existing two 3.5 tonne boilers on site.

The new vertical coil Steam Generators feature three full gas passes, plus an in-built combustion air pre heater to give high operating efficiency.

The pressure containing coil design of the Steam Generators form the main combustion chamber with the second and third passes for the gasses going between the coil windings to ensure high gas velocity with good heat transfer and self cleaning of the flue gas passes.
A purpose built and matched Babcock Wanson burner ensures long life and simple operation.

The new Steam Generators at Grain LNG are fully automated with automatic unattended start and stop capability.

Highly bespoke, they have been designed with specialist PLC interfaces and controls, which also enable automatic changeover between the two generators on demand. They have also been adapted to operate at a lower steam pressure than is standard to work with the existing steam system on site.

As you would expect in such a demanding environment, the new Babcock Wanson Steam Generators are rugged in construction and include ATEX rated gas controls for use in potentially explosive atmospheres.

To ensure continued smooth operation in such a critical site, National Grid has agreed a maintenance service contract with Babcock Wanson, tailored to meet their precise needs. This contract provides a six-monthly burner service to both Steam Generators to ensure trouble-free operation and to check all safety devices, controls and limiters.

In addition, Babcock Wanson will attend during the annual strip down inspection, in order to complete a burner service and additional yearly checks to ancillary equipment and controls.

Babcock Wanson offers a complete range of products and services for boiler houses and other process heating needs, from firetube steam boilers, thermal fluid heaters, rapid steam generators, water treatment equipment and services, process air heating solutions and hot water boilers to VOC and odour treatment by Thermal Oxidation.