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Title: Hydrocarbon-oil encapsulated bubble flotation of fine coal. Technical progress report for the fourth quarter, July 1, 1991--September 30, 1991

Technical Report ·
OSTI ID:10109946

This report is concerned with the progress made during the fourth period of the research Project, Grant no. DE-FG22-90-PC90314. A main portion of this reporting period has been consumed in the following tasks: (i) induction time measurement for the coal particles prepared by using various modes of collector addition techniques; (ii) ultrasonic energy dispersed collector flotation tests; (iii) natural floatability measurement using Hallimond tube flotation cell; (iv) preparation and operation of 3-inch column cell, and (v) preparation of wettability measurement using film flotation method. The coal samples used in this period of work are four ranks of coal samples from Mammoth (Anthracite), Lower Kittanning, Upper Freeport and Pittsburgh No. 8 seam coals. The results showed that a drastic improvement in the flotation rate and yield were achieved by using the ultrasonic energy dispersed collector flotation compared to that of conventional flotation. The techniques of direct liquid addition and addition of ultrasonic energy dispersed collector are mainly for alteration of the hydrophobicity distribution of coal particle surfaces. On the contrary, the gasified collector addition to the gas phase technique is for alteration of the chemical properties of bubble surfaces. Among these techniques, however, the results showed that the hydrocarbon oil encapsulated bubble flotation is more selective than either ultrasonic energy dispersed collector flotation process or conventional flotation process. Induction time measurement was continued and extended to the coal samples received in this period of work, using oil free air bubble and oil-coated air bubbles. Induction time for oil-coated bubbles is significantly shorter than that of oil-free bubbles for all the coal samples used. A good agreement between flotation responses and induction time were obtained for all the coal samples under the conditions of various modes of collector dispersion.

Research Organization:
West Virginia Univ., Morgantown, WV (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
FG22-90PC90314
OSTI ID:
10109946
Report Number(s):
DOE/PC/90314-T8; ON: DE95005510; TRN: 95:001399
Resource Relation:
Other Information: PBD: [1995]
Country of Publication:
United States
Language:
English