<p>Handling Spent SCR Catalyst</p><p>EPRI report, SCR Catalyst Disposal, Recycle, and On-Site Washing/Rejuvenation Options (1016397), is now available for download. This recently published report addresses several topics associated with spent Selective Catalytic Reduction (SCR) catalyst, including technology options and current utility experience. </p><p>How to Apply the Results The results presented in this report will help utilities better understand the alternatives for handling spent catalyst, including the current state-of-the-art and the costs. This knowledge will allow plant staff to make more informed decisions when it comes to handling spent catalyst. </p><p>The report is available for download by clicking the link below.</p><p>Background SCR technology has become widespread within the fossil-fueled utility industry and is the technology of choice when high levels of nitrogen oxides (NOx) reductions are required. The current and expected future utilization of SCR will result in significant volumes of spent SCR catalyst being generated by the industry as a whole. </p><p>The rate of spent SCR catalyst being generated is increasing proportionally to the implementation of the technology, as well as the aging of the SCR fleet as a whole. The total yearly spent catalyst generation rate is estimated to be 17,000 tons per year and is projected to reach 30,000 tons per year by 2020. Current practices for managing spent catalyst include catalyst reconditioning (regeneration/rejuvenation/washing), disposal, and recycling.</p><p>Decision-making Regarding Spent Catalyst The EPRI report provides information on (1) catalyst characterization; (2) technologies for disposal, recycling, and on-site washing/rejuvenation; (3) current utility experience; and (4) research and development needs:  Catalyst Characterization. Characterizing spent catalyst, or defining its makeup, is an important part of the evaluation process when determining the ultimate fate of the catalyst. Disposal characterizations mainly center on the leaching behavior of spent catalyst in a landfill scenario. Characterizations in support of catalyst recycle evaluate the recoverable materials and associated costs and benefits. These characterizations establish the relative weights of metals and ceramics and the processing required to recover these materials. On-site washing/rejuvenation evaluations mainly center on determining the nature of catalyst deactivation and the expected performance of on- site washing/rejuvenation in restoring catalyst functionality.  Technologies for Disposal, Recycling, and On-Site Washing/Rejuvenation. EPRI’s evaluation of current technologies showed that the primary method of catalyst disposal is via landfill. Economically, landfill disposal costs are a strong function of the locale in which the waste is generated and whether it is treated as a hazardous or non-hazardous waste. Current recycle paths mainly recover bulk metals, with the </p><p>1 actual ceramic catalyst material typically being disposed. On-site washing/rejuvenation may be a viable option for some spent catalysts depending on the application and characteristics of the catalyst, thus providing an alternate to catalyst disposal or recycle.  Current Utility Experience. Current utility experience shows that most spent SCR catalyst has been landfilled. Recycle has primarily been limited to recovery of bulk metals associated with the catalyst modules or catalyst support streams. The resulting removed metals are typically sold as scrap, and the ceramic material is typically landfill disposed. On-site washing/rejuvenation has been performed with good success in a number of instances. This option is especially attractive for relatively fresh catalyst that has experienced acute fouling as a result of large particle ash, for instance.  Research and Development Needs. From a research and development perspective, a database documenting the behavior and characteristics of spent SCR catalyst could support the decision-making process needed to determine the catalyst’s fate. From a recycle standpoint, the utility industry could benefit by finding recycle options for the ceramic catalyst materials. For on-site washing/rejuvenation, little information relative to the long-term effectiveness of the process is available, especially for “low- tech” processing performed without the assistance of outside support firms. Research programs evaluating long-term performance of on-site washing would benefit utilities considering this option.</p><p>Related Research Over the past few years, EPRI has conducted comprehensive assessments to track the performance of regenerated SCR catalysts. The project has examined the performance of various regenerated and new catalysts in key areas, including NOx activity, conversion of sulfur dioxide (SO2) to sulfur trioxide (SO3), long-term deactivation rates, and mercury oxidation behavior.</p><p>Results have been published in several EPRI reports, including the following: Mercury Oxidation Behavior of New, Aged, and Regenerated SCR Catalysts (1014252), Impacts on Regenerated Catalyst on Mercury Oxidation, DeNOX Activity, and SO2-to-SO3 Conversion — Addendum (1015340), and Domestic and International Experience with Reconditioned SCR Catalyst (1010328). </p><p>For more information contact Alex Jimenez, 650-855-2051, [email protected].</p><p>View or download SCR Catalyst Disposal, Recycle, and On-Site Washing/Rejuvenation Options (1016397).</p><p>2 3</p>