Minimum ignition temperature of nano and micro Ti powder clouds in the presence of inert nano TiO2 powder.
Minimum ignition temperature (MIT) of micro Ti powder increased gradually with increases in nano-sized TiO2 employed as an inertant. Solid TiO2 inertant significantly reduced ignition hazard of micro Ti powder in contact with hot surfaces. The MIT of nano Ti powder remained low (583 K), however, even with 90% TiO2. The MIT of micro Ti powder, when mixed with nano Ti powder at concentrations as low as 10%, decreased so dramatically that its application as a solid fuel may be possible. A simple MIT model was proposed for aggregate particle size estimation and better understanding of the inerting effect of nano TiO2 on MIT. Estimated particle size was 1.46-1.51 μm larger than that in the 20-L sphere due to poor dispersion in the BAM oven. Calculated MITs were lower than corresponding empirically determined values for micro Ti powder because nano-sized TiO2 coated the micro Ti powder, thereby decreasing its reaction kinetics. In the case of nano Ti powder, nano-sized TiO2 facilitated dispersion of nano Ti powder which resulted in a calculated MIT that was greater than the experimentally determined value.
Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines, Northeastern University, Shenyang 110819, China. Electronic address: yuanchunmiao@mail.neu.edu.cn.
Chunmiao
C
Yuan
Process Engineering & Applied Science, Dalhousie University, 1360 Barrington Street, Halifax, NS B3J 2X4, Canada.
Paul R
PR
Amyotte
Process Engineering & Applied Science, Dalhousie University, 1360 Barrington Street, Halifax, NS B3J 2X4, Canada.
Md Nur
MN
Hossain
Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines, Northeastern University, Shenyang 110819, China; Department of Civil Engineering, Shenyang Jianzhu University, Shenyang 110168, China.
Chang
C
Li
D005107:Explosions; D006358:Hot Temperature; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D008962:Models, Theoretical; D010316:Particle Size; D011208:Powders; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D044366:Transition Temperature
D011208:Powders; C009495:titanium dioxide; D014025:Titanium
Ignition sensitivity; Minimum ignition temperature; Nanopowder; Solid inertants; Titanium powder