Norwegian carbon-storage planners have unveiled the results of months of studies on how to rid the hydrocarbon-heavy country of carbon-dioxide by ship, pipe and sub-sea storage, and the leading concept is injecting carbon beneath the maturing Troll gas field, one of Europe’s largest.

The Sognefjord Johansen formation 500 metres below the Troll field is considered lower risk than storing carbon in parts of the Nordic country’s giant Utsira saline aquifer, into which the Sleipner platform already disposes of 1 million tonnes of carbon-dioxide a year in a project closely watched by Europe. A Troll well site is being evaluated, although potential leakage into the vital economic organ is of stately concern.

Though 1,000 m below the seabed, about a third of Utsira is deemed too risky for the long-term storage of carbon-dioxide. But it’s still Europe’s great hope: An 8- to 12-inch pipeline to Sleipner from onshore sources is the plan estimated to cost NOK4.6 billion ($850 million).

The pipeline is still seen as cheaper than shipping carbon by Norwegian planners who also looked at a mooring buoy concept for unloading the gas. Government has seen four such concepts, although hampering all planning is the dearth of knowledge relating to the right mix for transport of carbon-dioxide, water and nitrogen.

Once at a newly modified Sleipner platform, sub-sea facilities at a new injection site will take on and deposit the carbon-dioxide gas bound for Sleipner-Utsira from Mongstad. Front-end engineering is expected to produce a concept by year-end 2008.

Onshore sources are expected to be 1.1 MMtc/y from Kaarstoe gas-fired power plant in 2012 and 1.3 MMtc/y from Mongstad in 2014. A small group of suppliers are involved in 40 projects to do with post-combustion carbon removal and storage.

The suppliers are being "incubated" by NOK200 billion ($37 billion) from interested Norwegian oil companies, NOK80 billion ($15 billion) from state company Gassnova and NOK50 billion ($9.2 billion) in Norwegian research funding.

“We have no alternative but to build,” Norwegian Oil and Energy Minister Aaslaug Haga said after her first of many forums for carbon-capture and storage, or CCS, in Oslo late Tuesday.

Her words were echoed by Briton Ron Oxburgh, a former Imperial College rector, arm's industry economist and now proponent of carbon sequestration to save the planet.

"There's alot of political will right now, and that's why there's the money," Oxburgh said.

"It'll be too late if we leave (CCS projects) to the normal economic forces," he added, asserting that recent European moves to boost carbon's importance was "not fast enough and not strong enough".

Focusing on coal, he said emitted carbon-dioxide had gone up over 50 percent since 1999, mostly on increased coal use in China and the United States. For all carbon projects, he said sequestration accounted for 80 percent of the cost, 15 percent of which was the cost of corrosion-resistant pipeline.

Among the challenges to overcome in the post-combustion removal of carbon is absorbtion and a solvent for the element. Stripping and “re-boiling”are other processes being addressed.

The use of amino acids and the spectre of their leakage into the atmosphere has Norway’s troika of environmental regulators involved in the carbon-scrubbing process. Amino acid is seen being used at the gas-plant project, while carbonate plant will scrub the refinery of its carbon.

For transport, moving carbon-dioxide at low pressure by liquefied petroleum gas ship is another peculiar challenge for the limited temperature range at which carbon is stable.

A report conducted for Gassnova hinted it would be cheaper, at NOK56 million ($11.5 million), to attempt moving carbon-dioxide by an existing LPG ship. A new ship design could cost NOK76 million ($12.6 million).

In all CCS scenarios, capital start-up costs are put at twice what operating costs are expected to be.

In contrast to the million tonnes a year sequestered from Mongstad, it was understood a first mock-up of plant is expected to capture just 100 tc/y for Danish DONG, StatoilHydro, Vattenfall and Shell. Gassnova expects a simulation of carbon-dioxide depositing to be ready by 2011.

Meanwhile, studies by U.K.-based MW Kellogg and Linde of Germany suggest cooling carbon and then piping it out from Melkoya in the Norwegian north to the Arctic gas field Snoehvit would cost about NOK680 million, around NOK20 million cheaper than building a new jetty and shuttle carriers. Linde is now understood to be doing the FEED for a pipeline version of Melkoya CCS.

ws@scandoil.com

Tags: Aker Kvaerner, Linde