- Title
- Characterization of "chailings": a char created from coal tailings
- Creator
- Tremain, Priscilla; Zanganeh, Jafar; Hugo, Lyndal; Curry, Shane; Moghtaderi, Behdad
- Relation
- NSW Environmental Trust
- Relation
- Energy & Fuels Vol. 28, Issue 12, p. 7609-7615
- Publisher Link
- http://dx.doi.org/10.1021/ef501829f
- Publisher
- American Chemical Society
- Resource Type
- journal article
- Date
- 2014
- Description
- Coal tailings are a waste product of the coal mining process and consist primarily of gangue mineral matter and fine coal particles. In this study, coal tailings sourced from two Australian coal mines (Mine A and Mine B) were subjected to a slow pyrolysis process at temperatures of 400–800 °C to create char hereafter known as “chailings”. Chailings were originally conceptualized based on the concept of biochar and are a novel waste management strategy for coal tailings. Several methods were used to characterize chailings and quantify the effect of different pyrolysis conditions. X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques identified the primary mineral constituents as silica (i.e., quartz) and aluminosilicates (i.e., kaolinite or illite). Clear morphologic changes were observed via optical and scanning electron microscopy (SEM) for increasing pyrolysis temperature, with evidence of swelling and devolatilization apparent at high temperatures (>600 °C). Proximate analyses indicated near complete devolatilization was apparent at 800 °C for both mines, with thermogravimetric analysis (TGA) revealing that peak devolatilization occurred at 455 °C for Mine A and 467 °C for Mine B. A substantial increase in surface area with increasing pyrolysis temperature was observed for Mine A chailings from 2.7 m2/g at 400 °C to 75.3 mm2/g at 800 °C, because of the presence of microporosity, while Mine B chailings decreased from 2.4 m2/g at 400 °C to 1.2 mm2/g at 800 °C, which was attributed to macroporosity and aggregation of particles. Properties of high-temperature (>600 °C) chailings, namely, surface area, porosity, and pH offer promise for future investigations regarding the application of chailings to soil.
- Subject
- coal; tailings; waste management; pyrolysis
- Identifier
- http://hdl.handle.net/1959.13/1296845
- Identifier
- uon:19312
- Identifier
- ISSN:0887-0624
- Language
- eng
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