| A hot gas particulate filtration system requires effective removal of particles to protect the downstream equipments. The leading technology for particle removal is the ceramic barrier filter technology. The ceramic candle filters are most promising to survive at temperatures up to 1600°F. At these high temperatures, there are certain problems that have to be dealt with candle filters. During the filtration process, with time, there is an accumulation of an ash cake on the outer surface of the filter. This causes the pressure drop through the thickness of the filter wall to increase with time. A back pulse in the form of compressed gas is applied periodically from within the filter to remove the ash cake on the outer surface of the candle filter for the filtration process to continue, a process called surface regeneration.;A thorough study of the experimental data for surface regeneration for a candle filter at high temperatures was performed. The data obtained from the long-term tests were validated using statistical process control tools and a simple analytical model for pressure variation was developed. A method to determine the thickness of ash on the filter surface at high temperature is identified and the key parameters that affect the surface regeneration process are presented. |
