Gas Tanks
| Isle of Grain, Kent |
|
| Contract: |
Balfour Beatty |
| Concrete Supplier: |
Hanson Premix |
| Volume: |
270,000 m3 |
| Admixtures Used: |
Glenium SKY |
Background
With gas demand rising and domestic production set to decline, the UK will need to import a significant proportion of its gas. The importation of liquefied natural gas (LNG) is set to fill part of the supply gap. Cooling natural gas to around -161oC until liquefied forms LNG.
Grain LNG Limited, a wholly owned subsidiary of National Grid, has constructed a liquefied natural gas importation and regasification terminal at the Isle of Grain in the south east of England. The terminal is the first of the country’s new LNG-import facilities and has been constructed following planning permission from Medway Council.
Initially Grain has the capacity to receive and process up to 3.3 million tonnes of LNG per annum, and a 20-year contract has been signed with BP/Sonatrach to enable them to import natural gas in liquid form from other countries. Three more LNG storage tanks (190,000m3 each) plus associated works are planned. This will enable LNG throughput at the site to be increased by 6.5 million tonnes per annum, making a total capacity of up to 9.8 million tonnes per annum. Expansion will take around three years to complete.
BASF Admixtures
To date three tanks have been produced, with BASF supplying Glenium SKY admixtures for the concrete used in the bases and the piling. Each tank, including groundworks, has used 45,000 m3 of concrete
BASF’s good relations with Balfour Beatty and Hanson Premix contributed to the specification of its admixtures on this project, however there was a further factor. BASF’s technical specialist commented that in many cases ‘piling is just piling’, but on this contract piling was particularly tight so there was no scope to knock the caps off the piling to get rid of excess water. A specific a technical advantage of using Glenium SKY in this instance was that it gave zero bleed, so avoiding the need for remedial action on the piling.
With three more full containment 190,000 m3 LNG storage tanks to be built, BASF hopes to supply the admixtures for the walls as well as the bases of these. This would involve the use of Delvo Stabiliser and Glenium Stream 2006L as well as Glenium SKY. The tank walls have to pass demanding cryogenic tests as a fault with the steel-lined tanks could lead to explosive failure if the surrounding concrete could not withstand the resulting temperature change. BASF has demonstrated that Glenium SKY passes the test in this situation.