Cutting costs with compact capture plants

If carbon capture is to be implemented on a large scale, the solutions must be financially sustainable. A group of actors led by the Fjell Technology Group in Bergen has enhanced the efficiency of a well-proven method.

– THE CAPTURE OF CO2 with solvents has been carried out for many years, but the method is based on technology developed in the 1930s,” says SINTEF Tel-Tek consultant and professor at the University College of Southeast Norway, Dag A. Eimer. Fjell, SINTEF Tel-Tek and CMR Prototech have worked together with Equinor over the last 10 years to develop a more efficient capture plant that requires less space.

HIGH PIPES TAKE UP SPACE “The use of solvents is about giving the chemicals enough time and contact with the flue gas to bind the CO2,” Fjell CTO Asbjørn Strand explains.

Traditional capture is carried out by releasing the waste gases through a high pipe. On their way up, the flue gas encounters CO2 binding chemicals– so-called solvents – which are sprayed down from the top and sides and absorb CO2. Then the solvent is transferred to a desorber, where CO2 released from the solvent.

“The absorption method can require a pipe that is several tens of metres high. This means that you will have a capture plant that requires a great deal of space, which both limits the areas of application and results in substantial investment costs,” says Strand.

While many projects in CLIMIT have contributed to the development of more efficient and less costly solvents, the Fjell Technology Group has looked at the opportunities to improve the actual capture plant.

ROTATING GASKETS “Simply explained, we have developed a compact plant that increases the surface area of the amine by means of rotating technology. This reduces the time that the flue gas must be in the capture unit, which also reduces the size of the plant,” Strand explains. The method also makes it possible to use concentrated and viscous solvents that absorb CO2 more efficiently. It is of no consequence what types of solvent are used. The technology is solvent neutral.

The Fjell Technology Group’s cooperation with Equinor, SINTEF Tel-Tek and CMR Prototech began already in 2007. That is when the group, under the management of Equinor, developed a compact “stripper” or desorber that separates the CO2 from solvents after carbon capture. This is the same group that is responsible for the new pilot for the absorber component of the capture plant, which is being tested now under the direction of SINTEF Tel-Tek at the University College of Southeast Norway in Porsgrunn.

“Work on the development of the absorber stopped in 2012, but upon agreement with Equinor, we took over the rights and resumed the work in 2015. We then had an idea about how we could solve the absorption process. We applied for and received support from CLIMIT, which has been decisive in getting us to where we are today,” says Strand. Statoil has also contributed financing.

“The technology is still immature, but the goal is to be ready with a compact plant that has a broad area of application, both in industry and on the oil platforms by the end of 2020. In addition to being space-saving, the concept will also be less costly than traditional capture plants.

“The investment costs will be significantly lower, and it also looks like the operating costs will be somewhat lower,” says Strand.

STORAGE IS DECISIVE If the carbon capture plant is to be interesting commercially, however, it is crucial that an infrastructure for transport and storage be put in place. Madsen anxiously awaits the start of the full-scale project for carbon capture, but he trusts that it will take place according to plan. “Almost all scenarios for how we can reach the two-degree target from the Paris Agreement require the capture of CO2 from power plants and industry. Wedo not have any alternative to paralleluse of carbon capture,” says Strand. “The earlier we get started, the better.”


CLIMIT © 2017