Abstract

This article presents background and the test results for a NOx control solution applicable to pulverized coal-fired power plants (E-NOx) that resolve the operating challenges related to the use of low/ultra-low-NOx burners (LNB) for in-furnace control and SCR or SNCR for post-combustion nitrogen oxides reduction. The major results of CFD modeling and test data are presented, which confirm E-NOx capabilities to reduce NOx and consequently the consumption of ammonia/urea for units using post-combustion NOx control. Basic steam plant performance analysis per ASME codes in combination with test data suggested an appreciable reduction in the plant heat rate. The results of economic studies of E-NOx applications for power plants with different means of NOx control are presented in this article, demonstrating a simple payback period to be within 8–16 months. This is the first environmental technology that pays for itself thanks to a decrease in both fuel and NOx reducing reactants consumption, thus lowering operating and maintenance costs in comparison with best available current and retrofit technologies.

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