Catalyst Regeneration
Catalyst Cleaning and Regeneration
Steag utilizes a patented deionized (DI) water-based process to remove the physical materials which plug or blind the catalyst layers. In the event of chemical deactivation, after the removal of the catalyst poisons or deactivation causes, Steag adds chemicals used in the original manufacturing of the catalyst to the regeneration process thereby restoring the catalyst it to its original activity level.
Steag has cleaned and regenerated several layers of catalyst a number of times and has found that there is no changed in the deactivation rate between new catalyst and cleaned and/or regenerated catalyst.
In January 2007, Steag relocated to its new headquarters and catalyst regeneration facility in Kings Mountain, NC to better serve our North American clients. Our catalyst storage facility is fully operational and the regeneration plant started operations in second half of 2007.
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First catalyst modules to be
regenerated at STEAG`s regeneration
plant in Kings Mountain, NC arrive from
the AES Somerset Plant. |
SCR catalyst regeneration tanks at STEAG’s state-of-the-art facility in Kings Mountain, NC. |
Steag’s Patented Regeneration Technology is Based on Effective
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• Removal of physical restrictions (blinding layers, fly ash and LPA)
• Removal of catalyst poisons (As, P, NA, K, CaSO4, etc.)
• Protection of the catalyst’s components providing structural integrity and mechanical
strength (i.e. WO3)
• Full activity restoration through replenishment of the catalyst’s active components
(V2O5, MoO3, WO3) by means of Steag's Selective Impregnation® process will result in a lower SO2/SO3 conversion rate depending upon the relative distribution of the catalytic activity V2O5. |
Steag’s Patented Processes
- The patented processes are fully flexible and can adapt to the catalyst deactivation causes and the client’s space limitations and budget considerations.
| • Cleaning |
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Removal of physical restrictions |
| • Rejuvenation |
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Removal of catalyst poisons without the need for replenishing catalytically active compounds – can often be done on site |
| • Regeneration |
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Removal of catalyst poisons plus addition of catalytically active ingredients – must be done off site |
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Catalyst before cleaning – deactivated
and plugged |
Catalyst after cleaning – Using Steag’s patented DI-water process
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Background
Steag found that the flue gas from burning a variety of bituminous coals, and certain secondary fuels such as bone meal, gradually deactivated the installed catalyst due to fly ash and large particle ash plugging and/or the formation of blinding layers on the catalyst surface.
Chemical deactivation also results from catalyst poisons such as arsenic, phosphorus and earth alkali metals which chemically react with the catalytically active ingredients of the catalyst, thus rendering them ineffective.
In 1997 Steag developed a catalyst cleaning and regeneration process which has been a major factor in reducing the O&M costs for our own fleet of SCRs.
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