(239c) Development and Experimental Results of Regenerable Fine Particulate Filters

Filtration of fine particles is a critical requirement to keep gaseous process streams operational, but can be especially challenging in extreme conditions (high temperature, low or high pressure, explosive fluids). Traditional processes use high efficiency particulate air (HEPA) filters to remove particles, but these are made from fibrous materials and are unable to withstand these extremes. In addition, high pressure drop associated with heavy loading leads to frequent disposal and replacement. Mainstream has examined multi-stage cyclonic separators combined with electrostatic precipitators as a regenerable alternative to HEPA filters. Mainstream will discuss our recent work on improved computation fluid dynamic modeling and experimental results with unique geometry cyclones resulting in improved capture efficiency at reduced pressure drop and how they change as a function of absolute pressure and gas type. In addition, we will discuss our experimental results on electrostatic precipitators in low-pressure systems and the effect of particle characteristics (e.g., resistivity, size), fluid properties (e.g., density, pressure), and field effects (e.g., corona onset, voltage, geometry) on capture efficiency and regeneration.