Effects of Operating Pressure and Stand-Off Distance on Coal Comminution by Waterjet


Comminution of coal to ultrafine sizes by high-pressure waterjet coupled with cavitation cell provides a novel method for preparation of coal-water fuels for next generation, near-zero emission electric power generation. To establish the fundamental performance of the waterjet mill, the effects of the operating pressure and stand-off distance were comprehensively investigated using a high ash bituminous coal. The comminution products were evaluated in terms of the particle size, particle size distribution, and surface area change. The experimental results indicated that the waterjet-mediated comminution of coal was strongly affected by all these operating parameters. Higher operating pressure led to finer products, while the efficiency of the waterjet mill in terms of particle size strongly depended on the stand-off distance. This research provides a deeper insight into the high-pressure waterjet for coal comminution and a basis for process parameter optimization.


Mining Engineering


This research was carried out at the Missouri University of Science and Technology (MS&T), Rock Mechanics and Explosives Research Center/Waterjet Laboratory, Rolla, Missouri, USA, using specially designed and built apparatus. Yaqing Li's M.S. research was supported by both by Dr. Galecki's funds and National Natural Science Foundation of China (Grant no. 51404192). During their post-doctoral research fellowship at Department of Mining and Nuclear Eng., MS&T, Dr. Gul Akar Sen was supported by TUBITAK, postdoctoral research fund R-2219 and Dr. Sezai Sen was supported by The Council of Higher Education of Turkey, international post-doctoral research fellowship program.

Keywords and Phrases

Coal; Comminution; Particle size distribution; Waterjet

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


File Type





© 2017 Oficyna Wydawnicza Politechniki Wroclawskiej, All rights reserved.

Publication Date

01 Jan 2017