“It turns out to be a clever way of doing things,” Ghoniem says. “The system is more compact, because at the same place where we do separation, we also burn. So we’re integrating everything, and we’re reducing the complexity, the energy penalty, and the economic penalty of burning in pure oxygen and producing a carbon dioxide stream.”
The group is now gauging the system’s performance at various temperatures, pressures and fuel conditions using their laboratory setup. They have also designed a complex computational model to simulate how the system would work at a larger scale, in a powerplant. They’ve found that the flow of oxygen across the membrane depends on the membrane’s temperature: The higher its temperature on the combustion side of the system, the faster oxygen flows across the membrane, and the faster fuel burns. They also found that although the gas temperature may exceed what the material can tolerate, the gas flow acts to protect the membrane.
“We are learning enough about the system that if we want to scale it up and implement it in a powerplant, then it’s doable,” Ghoniem says. “These are obviously more complicated powerplants, requiring much higher-tech components, because they can much do more than what plants do now. We have to show that the [new] designs are durable, and then convince industry to take these ideas and use them.”
The lab work and the models developed in Ghoniem’s group will enable the design of larger combustion systems for megawatt plants.
Madhava Syamlal, focus area leader for computational and basic sciences at the National Energy Technology Laboratory, says simulations such as Ghoniem’s will help push next-generation technologies such as oxygen-separating membranes into powerplants. “We have seen that in other areas, like aircraft, simulations really improve how the product is developed,” Syamlal says. “You can use simulations and even skip some of the intermediate testing and go directly to designing and building a machine. In the energy industry, these are the pieces we need to increase the scale quite rapidly.”
Ghoniem’s group includes research scientist Patrick Kirchen and graduate students James Hong and Anton Hunt, in collaboration with faculty at King Fahed University of Petroleum and Minerals (KFUPM) in Saudi Arabia. The research was funded by KFUPM andKing Abdullah University of Science and Technology.
Source: Massachusetts Institute of Technology (MIT).
