A method for reducing the emissions from combustion gases produced during a combustion process includes injecting a hydrocarbon-based reducing agent into the combustion gases to form a combustion gas mixture. The combustion gas mixture including oxides of nitrogen, NO.sub.x, is directed through a selective catalyst reduction (SCR) system including a catalyst bed to remove NO.sub.x from the combustion gas mixture and to produce an exhaust gas. In one embodiment, the exhaust gases are released from the SCR to the atmosphere.