Doctoral Dissertations

Keywords and Phrases

20 liter; ASTM E1226; Coal dust; Combustible dust; Dust explosion; Siwek 20 liter


Coal dust explosibility is a health and safety concern that has been a recognized hazard for over 100 years. Initial testing by the Author using a Siwek 20L apparatus recorded a secondary maximum pressure at higher dust concentrations (1,000-7,000g/m3) with Pulverized Pittsburgh Coal (PCC). Higher dust concentrations are beyond the typical ASTM E1226 testing procedure but are possible in mining and processing scenarios. No reference documents have been discovered that show a secondary maximum pressure at higher dust concentrations. Literature reviewed identified that once a coal dust concertation generates a peak pressure, the pressure remains constant or decreases only slightly with continuously increasing coal dust concentrations.

The primary goal of this research is to investigate the source of a secondary peak pressure for higher concentrations of PPC dust. Testing presented within this dissertation has shown that the maximum explosion pressure does not behave in a linear fashion as concentration levels increase.

The Author’s proposed theory is the particle size distribution in a given sample, at higher concentrations, is undergoing secondary comminution and air classification during injection that leads to an enrichment of fines being tested. The dust being combusted during the explosive testing is not the same dust loaded into the test apparatus. The dust being evaluated within the combustion chamber possesses a higher quantity of fine PPC dust and has less mass than the sample loaded. To date, the Author has tested PPC dust concentrations ranging from 30 to 3,000 g/m3. To test the Authors theory four objectives were identified and evaluated”--Abstract, page iii.


Johnson, Catherine E.

Committee Member(s)

Worsey, Paul Nicholas
Galecki, Greg
Perry, Kyle A.
Liou, Frank W.


Mining Engineering

Degree Name

Ph. D. in Explosives Engineering


Missouri University of Science and Technology

Publication Date

Fall 2021


xiii, 82 pages

Note about bibliography

Includes bibliographic references (pages 79-81).


© 2021 Jacob Lee Miller, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11958