A method of reducing the concentration of pollutants in a combustion flue gas having a first temperature is provided. The method includes the step of providing an organic Rankine cycle apparatus utilizing a working fluid and including at least one heat exchanger is arranged in thermal communication with the flue gas. The method further includes the step of reducing the temperature of the flue gas to a second temperature less than the first temperature by vaporizing the working fluid within the heat exchanger utilizing thermal energy derived from the flue gas. The method further includes the step of filtering the flue gas through at least one filter disposed downstream of the heat exchanger to remove pollutants from the flue gas. An associated system configured to reduce the concentration of pollutants in the combustion flue gas is also provided.