Capturing carbon

By Michael Rogers

Technology Centre Mongstad serves as an incubator to test technologies that can be used for full scale carbon dioxide capture
Technology Centre Mongstad serves as an incubator to test technologies that can be used for full scale carbon dioxide capture (photo: TCM)

Carbon capture and storage (CCS) is once again back in the limelight, garnering interest as a viable tool in reducing carbon dioxide emissions. Globally, a few large-scale CCS projects have been developed and implemented, but to meet the goals set out during the latest annual UN climate conference, COP24, much more will need to be done to scale back the amount of COrelease.

As technologies have been refined, “utilisation” has also become a real option – CCUS – opening the potential for using captured carbon in industrial processes (carbon fibre, for example) as well as for feedstock in producing fuels.

According to the International Energy Agency (IEA), the United States, with 10 running projects, now captures approximately 25 million tonnes of COper annum. Next is Norway with two operational CCS projects, capturing nearly 2 million tonnes – impressive considering the country’s size and population. Worldwide, 17 large-scale CCUS projects account for 30 million tonnes of captured CO– and more are on the drawing board or being developed.

Not a bad start, but considering that energy related emissions topped 32.5 billion tonnes in 2017 (IEA), CCUS will need to be expanded and improved to do more to reduce carbon dioxide emissions.

USA
With 10 major CCS projects under way, the U.S. Department of Energy (DOE) recently announced up to USD 30 million in funding for cost-shared R&D for front-end engineering design (FEED) studies for COcapture systems – for both coal and natural gas power plants. The stated goal is to drive down the cost of implementing CCUS ahead of wide-scale deployment of the technology.

The DOE highlights North America’s largest CCS project, Petra Nova Project, near Houston, Texas, which has captured emissions roughly equivalent to 350,000 automobiles per year – more than 1 million tonnes of COper annum – since its commencement in 2017. Funded by a USD 190 million DOE grant for the project, captured COis shipped by pipeline 130 kilometres for injection to increase oil recovery.

Norway
In Norway, Equinor has developed and operates the two fully operational CCS projects: Sleipner and Snøhvit.

In the Norwegian sector of the North Sea, approximately 1 million tonnes of COare now captured annually from the natural gas on the Equinor-operated Sleipner field. Equinor injects this COinto a saline formation 1 km below the seabed. By 2016, when Sleipner CCS celebrated its twentieth anniversary, over 17 million tonnes of CO2 had been stored.

In the Barents Sea, at the Equinor-operated Snøhvit field, natural gas containing 5-6% COis piped to the Melkoya gas processing facility, near Hammerfest. Since 2008, the the COseparated from the gas, using amine capture, is piped back to Snøhvit and injected into a saline aquifer 2,400 metres below the seabed.

Technology Centre Mongstad
Equinor’s Mongstad refinery on Norway’s west coast has been in operation since 1975, following closely on the heels of the country’s first oil production. In 2012, Technology Centre Mongstad (TCM) opened at the refinery to serve as an incubator to test technologies that can be used for full scale CO2capture.

Owned by the Norwegian State – Gassnova overseeing the Norwegian Government’s 77.5% stake – together with Equinor, Shell and Total, TCM currently captures up to 100,000 tonnes of CO2each year as part of testing activities.

TCM’s primary focus is on post-combustion, and the facility includes two units to test different solvent-based capture solutions and two live industrial flue gas sources with COconcentrations ranging from 3.5% to 13%. These testing facilities include 100 different sampling points and approximately 4,000 sensors that are connected to a central control room.

Gassnova and TCM are now working towards creating what could become Europe’s first industrial full-scale CCS project. A 2016 feasibility study identified three possible locations for the project, and funding for planning studies for two of the locations has been approved. The final investment decision is expected in 2020/2021.

The future
The oil industry has decades of experience using COinjection as a tool to increase reservoir pressure for enhanced oil recovery, which makes the reduction implementation and running costs as well as mitigating risk the most fundamental goals for continued CCS studies.

Expanding CCS/CCUS efforts, in addition to fuel efficiency and transition to renewable sources, can contribute to a lower carbon future.

As part of testing activities, TCM currently captures up to 100,000 tonnes of carbon dioxide each year
As part of testing activities, TCM currently captures up to 100,000 tonnes of carbon dioxide each year (photo: TCM)