Researchers at Alden have been modeling selective catalytic reduction (SCR) systems both physically and computationally for the better part of a decade. Our ability to define and improve on the fluid flow phenomena, species, and thermal mixing and particulate transport dynamics within SCR models leads to practical recommendations for optimal SCR performance.
Using physical and/or computational flow modeling techniques, Alden can determine the uniformity of the fluid and thermal distributions. To ensure that the SCR systems will perform up to the stated levels of NOx reduction with minimal reactant "slip," our models are used to develop the flow controls and mixing devices to achieve the targeted levels of uniformity.
SCRs operate in a hot gas environment (T ≈ 700º F) and are typically situated upstream of air preheaters and flyash collection equipment. Particulate modeling is employed to develop modifications that enhance ash collection in the economizer outlet and SCR inlet duct hoppers in order to prevent large particle ash (LPA) from reaching the SCR module and plugging the catalyst passages.
Alden's Air & Gas Flow Modeling Group maintains a facility for determining the true aerodynamic characteristics of LPA. This information is critical for the accurate modeling of LPA/SCR interactions.
