Linde develops CCS technology

The elimination of energy industry carbon dioxide emissions is becoming large-scale business. The European Union intends to use income from emissions trading to fund more ecologically friendly ways of producing energy. Dr Bernd Holling and Dr Gerhard Beysel, representatives of The Linde Group, visited Finland to bring the latest news in the field.

Energy production resulting in greenhouse gas emissions is reaching the end of the road in the EU countries. Holling says that Europe is a model student in reducing its emissions, whereas developing countries like China is adding to greenhouse gas emissions by commissioning establishing on average one new coal-fired power plant every week within this year. "The EU is investing heavily in the development of carbon capture, while the rest of the world seems to have adopted an indifferent attitude towards greenhouse gases and its impact on global warming. Supported by the European Commission, Europe plans to have twelve operational demo-power plants developed with carbon capture by 2015."

Gerhard Beysel admits that greenhouse gases are a particularly German problem, as the country's energy production exploits brown coal. "Our coal is an extremely unfavorable source of energy from the carbon dioxide perspective. However, it is not only a German problem, as the energy companies have Nordic owners, and brown coal is in fact ancient Nordic forest which has traveled south with the Ice Age. The warming of the climate caused by greenhouse gases is an international rather than a national problem," reminds Beysel.

According to Holling, Finland receives a good grade in carbon footprint measurements. Carbon-neutral energy sources in particular, such as hydro-electric power and nuclear power, lift Finland to an entirely different category from Germany, Spain, the Netherlands and Great Britain. France also fares well in such comparisons due to its extensive use of nuclear power.

Not under my house

Carbon capture technology is being developed with strong EU support. The idea is to subsidize research and development activities, pilot plants and demonstration plants using EU funds and income from sold CO2 certificates of emissions trading. Carbon capture must compete for the subsidies with renewable energy technologies. However, Holling doubts the sufficiency of growth rate of renewable fuels to replace fossile fuelssources in the global energy demand. "They play a growing portion in the enegy balance. But coal is the most important source for electricity, and will continue to be so for quite some time."

There are several ways to realize a near zero emission power plant:reduce the emissions of carbon combustion. Oxyfuel combustion is one of these technologies, otherwise carbon dioxide can be captured from the fluegas with the aid of gas scrubbing as alternative and gasification as third technology. Holling stresses that the separation of CO2 is not a technical impossibility. Much more investigation has to be done in the area of storing the CO2 underground.

Beysel sees the pumping of carbon dioxide back into oil or gas fields as a serious alternative. This method is very well known as EOR (Enhanced Oil Recovery) and practiced worldwide since many years and procedures for similar tests have already started in Germany in Maxdorf, near Berlin. "The project proved challenging. Everyone approves of the subterranean storage of carbon dioxide in theory, as long as it is not pumped under their house. No one seems to want greenhouse gases in their neighborhood," regrets Holling.

Experts at Linde see the sequestration of greenhouse gases in sandstone (saline aquifers) as one of the most promising alternatives, because large potential storage sites exist in Europe, especially in the northern part of Germany and neighbouring countries close to the North Sea. "Sandstone is full of tiny little holes. In nature water accumulates in these holes. Carbon dioxide injected into the stone would displace the water. This would allow large amounts of greenhouse gases to be stored inside the stone," says Bernd Holling.

The capture of greenhouse gases is but one alternative among many. The two men of technology get clearly enthused when given the chance to talk about hydrogen economy. Linde already has hydrogen stations across Germany, with the purpose of offering a carbon-free alternative to motorists. "When you burn hydrogen, all you produce is water," says Beysel enthusiastically. Chemistry can be wonderfully inspiring.


- Article published in Kemia 1/2010 (Finnish Chemistry magazine)