抄録
Dust deposition inside of sampling tubes was evaluated using a test system which consisted of a sampling nozzle with a 90° bend, a sampling tube with ten 20-cm glass pipes, an elbow and a dust collector. The deposition test was carried out as a function of suction gas velocity and tube diameter using calcium carbonate (dp50=3.8μm, C=300mg/m3) as the test dust. The test results showed that 33-68% of the test dust was accumulated, and most of the deposition occurred in the 90° bend of the sampling nozzle.
Grit injection into the 90° bend of the sampling nozzle was tried using large sand particles (dp50=300μm) as a countermeasure of dust deposition. About 93% of the dust deposited inside of the sampling nozzle could be blown off within four minutes of grit injection. Simultaneous grit injection with dust sampling was also confirmed to be fully efficient.
