Stress State Interpretation of Dust Cake Detachment from Ceramic Candle Filters
In advanced coal-or biomass-based power applications,hot gas filtration systems are key components designed to protect the downstream heat exchanger and gas turbine components from particle fouling and erosion,as well as to clean up the process gas to meet emission requirements.Ceramic candle filters are promising choice of filtration technology as they serve at high temperature,while feature both considerable resistance to corrosion and high collection efficiency; however,their long-term performance,durability and life are essential to the successful operation of the hot gas filtration system in Integrated Gasification Combined-Cycle (IGCC).Char and ash fines in filter cake can potentially have a harmful impact on the life of porous ceramic candles.Hence,it is needed to remove the dust cake,which accumulates on candles,from outer surfaces of candles in adequate intervals,since dust cake raises the pressure drop.A technology that enables the removal of the accumulated dust is thus crucial to the successful long-term operation of ceramic candle filters.A simplified theory is developed that yields the approximate stresses within a dust cake on the outer surface of ceramic candle filter and gives the critical factors which ensure complete detachment of cake.The radial and tangential stresses in cake during filtration have been derived by consideration of active state of stress in the dust cake.Back pulses of cleaning gas expand dust cake on the condition,that their power is just adequate to the properties of cake,such as angle of internal friction and cohesion.Expansion of dust cake induces tension cracks and disintegration of cake.Back pulses of higher values hamper expansion of cake and cause “patchy cleaning
syngas cleanup:pollution:filtration:dust:ceramic candle filter:dust cake detachment.
Yau-Pin Chyou Jiri Smid Shu-San Hsiau
Institute of Nuclear Energy Research,Atomic Energy Council,No.1000,Wunhua Rd.,Longtan Township,Taoyu Graduate Institute of Energy Engineering,National Central University,No.300,Jungda Road,Jhongli 3200
国际会议
The 8th International Symposium on Gas Cleaning at High Temperatures(第八届国际高温气体净化技术研讨会 GCHT-8)
太原
英文
288-297
2010-08-23（万方平台首次上网日期，不代表论文的发表时间）