In addition to Nebb’s development projects, several other companies and organizations around the world focus on the development of parts and variations of the oxyfuel process. A few of the main development projects are mentioned below.
Turbines and combustion systems
Efficient turbines and combustion systems are essential in Nebb's oxyfuel power cycles. Nebb cooperates with Siemens and Clean Energy Systems for the development of turbine and combustion systems for oxyfuel processes based on gaseous and liquid fuels. In the first projects, steam turbines can be a good solution. In the long term, highly efficient oxyfuel gas turbines will be developed. This development will increase the efficiency of the power cycles significantly. For more information about some of the ongoing oxyfuel gas turbine development, see:
Air separation is a major energy consumer and cost driver in any oxyfuel process. The current state of the art technology is a cryogenic distillation of air. This is a mature technology, although the large oxygen consumption in full-scale CCS projects leads to the development of larger single-train units. The next-generation technology for air separation is expected to be based on Ion Transport Membranes (ITM), also called Oxygen Transport Membranes (OTM). This is a type of Mixed Conducting Membrane (MCM). It is a technology where the oxygen is ionized on the feed side of the membrane, conducted through the dense membrane as O2-, and reduced to O2 on the permeate side. The process requires high temperatures, typically 900°C. The membrane is 100 % selective for oxygen and thus produces very pure oxygen.
The process has the potential to create a step-change in the oxygen production energy requirement and cost, and thus also to reduce the cost of oxyfuel power production.
Air Products is currently scaling up their ITM technology, and it is expected to reach commercial size within a few years. They have indicated that the cost of oxygen for oxyfuel processes can be reduced to half and that the energy requirement can be reduced even more! Read more about the technology at:
Praxair is developing an ITM (or OTM) for syngas, where the oxygen is consumed on the permeate side of the membrane. This is also a very interesting technology for oxyfuel power production. Read more here:
Some of the projects mentioned above have recently received significant funding from the Department of Energy (DoE). In addition, Futuregen, a prestigious clean coal initiative in the USA has been changed from Integrated Gasification Combined Cycle (IGCC) to oxyfuel. Read more:
More information about oxyfuel and CCS can be found at: