Microwave enhanced high gradient magnetic desulfurization of coal

Technical Report · Sat Oct 01 00:00:00 EDT 1988

DOI:https://doi.org/10.2172/7222395· OSTI ID:7222395

Kelland, D. R. ^[1]

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1. Massachusetts Inst. of Tech., Cambridge, MA (USA). Francis Bitter National Magnet Lab.

This project consisted of several related lines of investigation, all leading toward the goal of improving the performance of high gradient magnetic separation (HGMS) in removing pyritic sulfur from eastern coals. The concept was to hear the pyrite included in coal, converting it to a more magnetic mineral form thus making more complete its removal by HGMS. The mechanism chosen was microwave irradiation. HGMS high magnetic fields and a high power microwave source was employed. We doubled the power density near the end of the project by halving the waveguide height. The magnetic properties of the coal minerals were studied by magnetometry and their chemical structure by Moessbauer spectroscopy, SEM and electron microprobe. Optical reflectance measurements, BTU and sulfur determinations were also made. We began with HGMS on whole coal samples: Upper Freeport, Pittsburgh and Illinois {number sign}6. Some were irradiated with microwaves up to 6 kW and others were retained as controls. We also measured the magnetization of pure mineral pyrite after direct contact heating. An extensive study of the microwave configuration in the waveguide was carried out at low power including the effect of having coal in the cavity. Finally, whole coal samples were subjected to microwave pretreatment in several atmospheres. In addition, a new technique of continuous axial HGMS was used to separate some constructed coal samples simply to demonstrate its possible application to improved coal desulfurization with magnetically enhanced coal pyrite. 108 refs., 160 figs., 12 tabs.

• Research Organization: Massachusetts Inst. of Tech., Cambridge, MA (USA). Francis Bitter National Magnet Lab.; General Electric Co., Schenectady, NY (USA). Corporate Research and Development Center
• Sponsoring Organization: DOE/ER
• DOE Contract Number: FG02-84ER13244
• OSTI ID: 7222395
• Report Number(s): DOE/ER/13244-1; ON: DE90008597
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL
MICROWAVE RADIATION
IRON SULFIDES
MAGNETIC PROPERTIES
DESULFURIZATION
EXPERIMENTAL DATA
MAGNETIC SUSCEPTIBILITY
MAGNETIZATION
MAGNETOMETERS
PYRITE
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
ELECTROMAGNETIC RADIATION
ENERGY SOURCES
FOSSIL FUELS
FUELS
INFORMATION
IRON COMPOUNDS
MATERIALS
MEASURING INSTRUMENTS
MINERALS
NUMERICAL DATA
PHYSICAL PROPERTIES
RADIATIONS
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
010300* - Coal
Lignite
& Peat- Preparation- (1987-)