The Effect of Solid-Bed Particles on the Material Wastage of In-Bed Tubes in the Fluidized Bed Combustor (FBC)

摘要

The material wastage and its rate that occur in AISI 1018 carbon steel used in in-bed tubes of the bubbling fluidized bed combustor are discussed with solid-bed particles. A series of material wastage tests was carried out by using the bed particle angular quartz silica (SiO{sub}2) on AISI 1018 carbon steel at an elevated temperature (300°C) condition. The tests were carried out in a nozzle-type material wastage tester. The different particle impact angles of 30°, 45°, and 90° were applied with different particle velocities. A low particle velocity test condition (2.5 m/s) attempted to simulate the conditions found in in-bed tubes of FBCs. A higher velocity test condition (30 m/s) provided data for comparison. Test results showed that maximum wastage occurred at a particle impact angle of 45°. Additionally, the material wastage rates for the low velocity were two to three orders of magnitude lower than that for the higher velocity. The morphologies of the test specimens were examined and analyzed by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). In the higher velocity condition, the specimen showed typical ductile mode erosion.