Type of Document Dissertation Author Hangsubcharoen, Monpilai Author's Email Address email@example.com URN etd-042999-164825 Title A Study of Triboelectrification for Coal , Quartz and Pyrite Degree PhD Department Mining and Minerals Engineering Advisory Committee
Advisor Name Title Yoon, Roe-Hoan Committee Chair Adel, Gregory T. Committee Member Bungay, Henry R. III Committee Member Karmis, Michael E. Committee Member Venkatraman, Partha Committee Member Keywords
- Triboelectrification, Particle Charging Mechanism,
Date of Defense 1999-04-22 Availability unrestricted AbstractThe separation efficiency of a triboelectrostatic separation (TES) for fine coal cleaning depends profoundly on the surface charges of the particles involved. In general, the larger the difference between the charges of the particle to be separated, the higher the separation efficiency. The premise that coal and mineral matter can be triboelectrically charged differently serves as a basis for the TES process. In order to improve the separation performance, it is apparent that a highly efficient charger is needed for the TES unit, as well as the information on the triboelectrification mechanisms of the coal and mineral matter.
Tribo- or contact electrification is a phenomenon in which electrical charge is usually transferred form one material to another, when two dissimilar materials are brought into rubbing or contact. In the present work, the triboelectrification mechanisms of coal, quartz, and pyrite were investigated in an in-line static mixer charger. A new in-situ charge-measuring device has been developed, in which an in-line mixer charger is located in side a Faraday cage. This makes it possible to observe the charging mechanisms of the particles when they pass through the mixer. This device was used to study the tribocharging mechanisms of coal, quartz, and pyrite as functions of the air velocity, particle feed rate, particle size, temperature, ash content, and the work functions of the materials that make up the in-line mixer. Evidence suggests that the charge transfer mechanisms of coal and mineral matter be due to electrons.
A new turbocharger designed and developed in the present study has been tested and used to investigate the triboelectrification mechanisms of coal and quartz. The charge measurements were conducted using a developed on-line charge-measuring device, which is based on the principle of the Faraday cage. The tribocharging mechanisms of coal and quartz were investigated as functions of the particle feed rate, particle size, rotor-blade rotation speed, ash content, and the type of the materials used to construct the turbocharger. The information on the charging mechanisms of the coal and quartz will be useful for improving the triboelectrification process and subsequently the design of a TES unit.
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28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access ACKNOW.PDF 6.22 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 APPENDIX.PDF 27.52 Kb 00:00:07 00:00:03 00:00:03 00:00:01 < 00:00:01 CH1-P1.PDF 113.06 Kb 00:00:31 00:00:16 00:00:14 00:00:07 < 00:00:01 CH1-P2.PDF 42.61 Kb 00:00:11 00:00:06 00:00:05 00:00:02 < 00:00:01 CH1-P3.PDF 92.67 Kb 00:00:25 00:00:13 00:00:11 00:00:05 < 00:00:01 CH1-P4.PDF 143.01 Kb 00:00:39 00:00:20 00:00:17 00:00:08 < 00:00:01 CH1-P5.PDF 81.97 Kb 00:00:22 00:00:11 00:00:10 00:00:05 < 00:00:01 CH1-P6.PDF 169.56 Kb 00:00:47 00:00:24 00:00:21 00:00:10 < 00:00:01 CH1-P7.PDF 197.49 Kb 00:00:54 00:00:28 00:00:24 00:00:12 00:00:01 CH1-P8.PDF 362.91 Kb 00:01:40 00:00:51 00:00:45 00:00:22 00:00:01 CH2.PDF 763.98 Kb 00:03:32 00:01:49 00:01:35 00:00:47 00:00:04 CH3.PDF 378.83 Kb 00:01:45 00:00:54 00:00:47 00:00:23 00:00:02 CH4.PDF 86.78 Kb 00:00:24 00:00:12 00:00:10 00:00:05 < 00:00:01 CH5.PDF 97.56 Kb 00:00:27 00:00:13 00:00:12 00:00:06 < 00:00:01 CH6.PDF 37.48 Kb 00:00:10 00:00:05 00:00:04 00:00:02 < 00:00:01 TITLE.PDF 11.81 Kb 00:00:03 00:00:01 00:00:01 < 00:00:01 < 00:00:01 TOC.PDF 16.54 Kb 00:00:04 00:00:02 00:00:02 00:00:01 < 00:00:01 VITA.PDF 6.11 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01
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