Oxy-coal combustion is a way to reduce CO2 emissions in power plants. Researchers studied the flue gas recycle in this process to find the best way to capture CO2. They looked at different ways to clean the flue gas, like using electrostatic precipitators and flue gas desulfurization. They also analyzed factors like the rate of flue gas recycle and the composition of the flue gas. The study found that the type of coal and how the plant operates affect the best way to capture CO2 in oxy-coal combustion.