With the increase use of energy, efficient small and distributable energy generation systems are needed to meet these demands. The oxy-combustion process is a proven technology for obtaining high combustion temperatures and results in an increased power generation efficiency from a given fossil fuel source and decreased greenhouse gas (GHG) emission. About 65% of an oxy-combustion plant net efficiency loss is due to electric power requirements by an air separation unit (ASU) . Currently the generation of O2 is economically viable only for larger electricity generation systems which need about 3,000 tons/day of O2. For the smaller generation process, where the requirements are of the order of 10 tons/day of O2, a cost effective method to generate O2 does not exist.
Currently O2 is separated from air using the traditional cryogenic separation process, cryogenic distillation-based air separation is costly and energy-intensive to operate. This process is energy intensive and consumes over 200 kWh of electricity per ton of O2 produced for plants in the range of 3,000 tpd of O2 produced. According to a large manufacturer of industrial gases, almost as much as 1,000 kWh is needed for a 10 tpd plant. In summary, the energy consumption of current cryogenic technologies is four to five times the theoretical minimum energy required for the process. The elimination of the energy consumption gap between theoretical and practical for small plants would decrease the O2 production costs and enable oxy-combustion as a viable option in small power generation systems.
