redOrbit: Ahmed Ghoniem of mechanical engineering leads an MIT effort to make coal plants cleaner by using a pressurized combustion system to capture carbon dioxide. Researchers at MIT have shown the benefits of a new approach toward eliminating carbon-dioxide (CO2) emissions at coal-burning power plants. Their system, called pressurized oxy-fuel combustion, provides a way of separating all of the carbon-dioxide emissions produced by the burning of coal, in the form of a concentrated, …