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Drilling Speeds
Published in C.P. Chugh, Ken Steele, V.M. Sharma, Design Criteria for Drill Rigs: Equipment and Drilling Techniques, 2020
C.P. Chugh, Ken Steele, V.M. Sharma
This is only one aspect of the matter. Some minerals (e.g. ‘kyanite’) have a hardness which differs on each crystallographic axis. Many minerals (e.g. the micas) will cleave easily in one specific plane only. In other minerals cleavage is in several planes (e.g. parallel to the three axes of the cube) and so perfect that if struck a tangential blow, a crystal will cleave to show a structure resembling a flight of steps.
Beneficiation Process of Kyanite-Rich Mineral Assemblages from Thassos Island Aegean Sea, Greece
Published in Mineral Processing and Extractive Metallurgy Review, 2022
Alexandra Gogou, Constantinos Mavrogonatos, Marianthi Anastasatou, Panagiotis Voudouris, Stephen Chryssoulis, Michael Stamatakis
The most important commercial property of the Al2SiO5 minerals is refractoriness (e.g., Agarwala and Agarwala 1950; McMichael 1990; Suri, Gupta and Tekin 2001). They have found applications in the ceramic industry, as raw materials to produce medium-grade alumina or mullitic refractories, as well as in the metallurgical and glass industry (e.g., Agarwala and Agarwala 1950; Chaouki, Iz-Eddine and Abderrahman 2014; O’Driscoll 1999, 2002) (Table 1). Their refractoriness depends on the alumina content and theoretically for pure Al2SiO5 it is 62.93%, however, such values are rarely attained because of impurities (Comodi et al. 1997). Commercial grades of kyanite must contain a minimum of 56% Al2O3, with less than 42% SiO2, 1% acid-soluble Fe2O3, 1.2% TiO2, and 0.1% each of CaO and MgO (Bennet and Castle 1983). There are many methods for the beneficiation of Al2SiO5 minerals (e.g., Ayhan and Abakay 2005; Jin et al. 2019; Zhou and Zhang 2011; Zhu, Deng and Chen 2014). Flotation is the most used method for fine-grained andalusite beneficiation, using several anionic collectors (e.g., Bulut and Yurtsever 2004; Jin et al. 2016a, 2016b; Li, Yuan and Yuan 1993; Zhou and Zhang 2011; Zhu, Deng and Chen 2014).
Binding gel characterization of alkali-activated binders based on palm oil fuel ash (POFA) and fly ash
Published in Journal of Sustainable Cement-Based Materials, 2018
Nurulhuda Nadziri, Idawati Ismail, Sinin Hamdan
The X-ray diffractograms of the unreacted POFA and fly ash are shown in Figure 1. The unreacted POFA consists of main crystalline phases of kyanite (Al2SiO5, PDF# 01-083-1567). Kyanite is a polymorph of andalusite and sillimanite. At 1100 °C, kyanite will decompose into mullite and vitreous silica [25]. The unreacted fly ash shows high intensity of quartz (SiO2, PDF# 00-005-0490) and mullite (Al6Si2O13, PDF# 00-015-0776).