MHI Mercury Removal System with NH_4Cl Injection

摘要

MHI has developed an effective Mercury Removal System that is integrated with the SCR and FGD. This technology uses the injection of ammonium chloride (NH_4C1) into the ductwork, upstream of the SCR catalyst and provides NO_x control and improved oxidation of elemental mercury. The downstream wet FGD effectively removes the SO_2 and the oxidized mercury with MHI ORP (Oxidation-Reduction-Potential) control technology. Southern Company and MHI successfully completed a full-scale demonstration of this Mercury Removal System at Alabama Power's Plant Miller Unit 1 (700MW) in April 2011, and have shown that this NH_4C1 can result in much lower operating costs than Activated Carbon Injection (ACI) and reduce the use of hazardous anhydrous ammonia injection. MHI has also developed advanced mercury oxidation catalyst, which requires lower halogens to oxidize the mercury. This report presents the demonstration results, including over 90% total mercury removal performance.