TU Darmstadt’s Institute for Energy Systems and Technology (TUD) has been conducting pilot-scale investigations of a “carbonate looping” method for CO2 capture. For some CO2 is a natural disaster in the making while others realize the molecule is the blood of all life on earth. Everyone could agree that mankind would do well to become better managers of the gas by CO2 recycling. It’s an important resource deserving more attention and less condemnation.
TUD is developing a way to virtually totally avoid CO2 emissions, while keeping energy inputs and operating costs extremely low. Any success would be quite an improvement, as carbon sequestration has to date been so expensive as to stop commercial testing. Coal combustion is expected to growth immensely outside the developed world insuring a very large increase in CO2 emissions over the coming decades.
TUD’s innovative method inexpensive and energetically efficient carbonate looping reduces power-plant CO2 emissions by more than 90 %. The engineering is under way for installation on an existing power plant.
TUD has been investigating the “carbonate-looping” method for the past four years, with success. Another major benefit of the carbonate looping method is that it’s expected to be easily retrofitted to existing power plants.
Carbon capture history has been successful while requiring very high-energy inputs and operating costs, which reduced the efficiency and stopped development. But, TUD hasn’t given up –
The research has evolved to the carbonate looping method emerging as a particularly promising approach that the Darmstadt researchers have studied for more than 1,000 operational hours.
The carbonate-looping method involves initially employing naturally occurring limestone for binding CO2 contained in power-plant flue gases in a first-stage reactor. The now pure CO2 is then reliberated in a second-stage reactor and may be further processed, stored or sold.
As the process graph shows the carbonate is fed to a second reactor where the CO2 is harvested from the carbonate and then carbonate is recycled back to the CO2 collection reaction.
The TUD pilot-scale research system proved capable of capturing more than 90% of the CO2 emitted which is good. But reducing both the energy input and operating costs formerly required for CO2 capture by more than 50% is even better.
Director Prof. Dr.-Ing. Bernd Epple with his staff of more than thirty coworkers investigating the method, remarked that, “This method represents a milestone along the way to CO2 free power plants and will allow coal-fired, natural-gas-fired, waste-derived-fuel-fired, and biomass-fired, power plants to reliably, cost-effectively, generate electricity and heat, without burdening the environment.”
Epple’s team has investigated and simulated in parallel indicating that the method would be suitable for utilization on full-scale systems.
The experience gained by the TUD group is currently being applied to a system that has been scaled up by a factor of twenty. The aim of that project, which is being supported by the German Federal Economics Ministry and various industrial associates, is planning such a scaled-up system for installation on an existing, German, power plant. For now which power plant will be involved remains to be decided.
The incentive in Germany is very high and intense. With a history including closing down the nuclear fleet, subsidizing intermittent wind and solar at incredibly high costs, social emotionalizing the CO2 global warming alarms, and an industrial economy soon to be starved of clean reliable and low cost power – something has to be done or an economic calamity will ensue.
Historically Germany responds technically quite well when stressed. This time its self imposed – so we’ll see just how effective and quickly they can come up with a solution for themselves and that may be an export market product soon after.