Bilfinger Berger Magazine 2/2008

TRAPPING THE CO₂ EMITTED BY COAL-FIRED POWER STATIONS COULD HELP TO STABILIZE THE CLIMATE. BILFINGER BERGER POWER SERVICES IS PARTICIPATING IN A PILOT PROJECT NORTH OF DRESDEN.

In summer 2008 the International Energy Agency (IEA) presented the G8 conference in Japan with an uncomfortable report: “If policies remain unchanged,” CO₂ emissions will rise by 130 percent by 2050, pushing temperatures up by six degrees Celsius. A development that according to the IEA could be avoided if only the technological potential were better exploited.
The CO₂ emitted by coal-fired power stations presents a particular problem for the climate. The IEA calculates that by 2030, coal consumption will be 65 percent greater than today, with the bulk of the increase attributable to the new economic powers of China and India. Against this background, research institutes and environmental bodies, consulting companies and the energy industry have turned their attention to the question of how to reduce the emissions released by burning coal.
The method that has been on everyone’s lips is CCS technology (carbon capture and storage) which aims to trap, compress and store the carbon dioxide created when coal is burned, rather than allow it to escape. One possible technique is currently being trialed at the Schwarze Pumpe power plant in Germany’s Lausitz region. Energy group Vattenfall has invested €70 million in a pilot plant where coal is burned in pure oxygen. Bilfinger Berger Power Services is participating in the project with a desulphurization unit.

TECHNOLOGY LEADER
The purpose of the desulphurization unit is to filter the exhaust fumes and extract the sulphur dioxide released when coal is burned. The Schwarze Pumpe project has some complex requirements, since virtually 100 percent of the sulphur has to be removed from the flow of carbon dioxide, so that the CO₂ can be compressed, transported and put into storage.
Bilfinger Berger Power Services is one of only a handful of companies that can manage the desulphurization technology necessary for this process: The company equips its systems with “tray absorbers” that enable this extremely high level of separation to be achieved. The process also requires substantially less energy than the methods used by competitors. Both of these advantages are now benefiting the Vattenfall pilot project.
Thus far, Power Services’ highly efficient desulphurization process has mainly been in demand for traditional coal-fired power stations. In Germany, Bilfinger Berger is currently fitting this technology to the new block at the Boxberg power plant. The Hamburg-Moorburg plant is next on the list, and an order has just been received from Belgium. There is also increasing interest from Eastern European countries where there are still many old power stations in need of modernization to meet European environmental standards. The market for specialist expertise covering all aspects of environmental protection is huge.
The right method of desulphurization to support CCS technology may already have been pinpointed, but plenty of questions remain. Cost-effectiveness is just one. In June 2008 Boston Consulting presented an analysis which indicated that CCS would only be worthwhile for a power plant operator when CO₂ emissions are trading at around €45. The current price is around half that. Nonetheless, there is a broad consensus reaching from the energy industry to environmental bodies such as the WWF. They all believe that CCS technology could indeed be decisive in the fight against global warming if it can be made to work as soon as possible and deployed in Asia—where coal consumption is rising dramatically. But there is still a long way to go. The CO₂ separation process still needs too much energy, safe underground storage facilities have yet to be found, and there are pipelines to build.
The Schwarze Pumpe pilot plant is the first step in trying out the technology. By 2015 a much larger demonstration plant is due to be up and running. If this proves that the process can be economically efficient, the first 1,000 megawatt block is planned for some time after 2020. CCS technology would then be available from 2030 at the earliest.

FUNDAMENTAL RESEARCH
For the time being, Bilfinger Berger Power Services will continue to focus on equipping traditional coal-fired power stations with its special desulphurization systems. The extremely high levels of sulphur separation— approaching 100 percent—that are achievable at a comparatively low energy cost are in themselves a minor revolution. The company regards its role in the Schwarze Pumpe pilot project as a contribution to basic research in the interests of providing energy for future generations.

Text: Daniela Simpson
Bilfinger Berger Magazine 2/2008