Pre-weakening behavior of magnetite quartzite based on high-voltage pulse discharge

Abstract To ascertain the mechanism that the ore grinding characteristics were improved by high-voltage pulse discharge (HVPD) pre-treatment, an innovative experiment system was performed on magnetite quartzite. The HVPD pre-treatment improved the −0.074 mm mass fraction in ground products, and the increase in pulse number effectively enhanced the mass fraction. The values of relative grindability (K1 and K2) increased with the pulse number significantly, whereas their value reduced as the grinding fineness and grinding time extended. A laser particle size analysis showed that the distribution of HVPD pre-treatment products was uniform. The particle size distribution and cumulative distribution curves satisfied the lognormal distribution function and power function, respectively. The Brunauer–Emmett–Teller (BET) analysis indicated that the specific surface area, total pore volume, and the porosity of crushed products were improved effectively by the HVPD pre-treatment. The internal ore structure became loosened, resulting in the decline in the mechanical properties of the ore; this is conducive to improve the grinding efficiency. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses indicated that the grain-boundary breakage was obtained via the HVPD pre-treatment selectivity.

[1]  I. Timoshkin,et al.  Liberation of minerals by high-voltage electrical pulses , 1999 .

[2]  Fengnian Shi,et al.  Modelling of high voltage pulse breakage of ores , 2015 .

[3]  Yuexin Han,et al.  Fluidization characteristics of a U-type reduction chamber in a suspension roaster , 2019, Powder Technology.

[4]  Stanislav S. Gornostayev,et al.  Improvement of phosphorus removal from iron ore using combined microwave pretreatment and ultrasonic treatment , 2015 .

[5]  C. Duan,et al.  The stripping effect of using high voltage electrical pulses breakage for waste printed circuit boards. , 2018, Waste management.

[6]  Yan Fazhi,et al.  Experimental investigation on anthracite coal fragmentation by high-voltage electrical pulses in the air condition: Effect of breakdown voltage , 2016 .

[7]  Emmanuel Manlapig,et al.  Pre-weakening of mineral ores by high voltage pulses , 2011 .

[8]  Igor V. Timoshkin,et al.  Energy consumption and liberation of minerals in explosive electrical breakdown of ores , 2001 .

[9]  F. Shi,et al.  Improving high voltage pulse selective breakage for ore pre-concentration using a multiple-particle treatment method , 2018, Minerals Engineering.

[10]  Igor V. Timoshkin,et al.  Liberation of valuable inclusions in ores and slags by electrical pulses , 2001 .

[11]  U. Andres,et al.  Liberation of mineral constituents by high-voltage pulses , 1986 .

[12]  Yuexin Han,et al.  Efficient enrichment of low-grade refractory rhodochrosite by preconcentration-neutral suspension roasting-magnetic separation process , 2020 .

[13]  U. Andres,et al.  Development and prospects of mineral liberation by electrical pulses , 2010 .

[14]  Solène Touzé,et al.  Investigation of lab and pilot scale electric-pulse fragmentation systems for the recycling of ultra-high performance fibre-reinforced concrete , 2018, Minerals Engineering.

[15]  Chenlong Duan,et al.  Liberation of valuable materials in waste printed circuit boards by high-voltage electrical pulses , 2015 .

[16]  Fengnian Shi,et al.  A t10-based method for evaluation of ore pre-weakening and energy reduction , 2015 .

[17]  Fengnian Shi,et al.  Progress and Challenges in Electrical Comminution by High‐Voltage Pulses , 2014 .

[18]  Yue-min Zhao,et al.  Enrichment of chalcopyrite using high-voltage pulse discharge , 2018, Powder Technology.

[19]  Yong-sheng Sun,et al.  Experimental study on fluidization characteristics of different-sized particles in a U-type reduction chamber , 2019, Advanced Powder Technology.

[20]  Fengnian Shi,et al.  Factors affecting electrical comminution performance , 2012 .

[21]  B. K. Kim,et al.  Electrical disintegration and micro-focus X-ray CT observations of cement paste samples with dispersed mineral particles , 2014 .

[22]  Fengnian Shi,et al.  Pre-concentration of copper ores by high voltage pulses. Part 2: Opportunities and challenges , 2015 .

[23]  T. Fujita,et al.  Crushing and Liberation of Materials by Electrical Disintegration , 2001 .

[24]  Fengnian Shi,et al.  Characterisation of pre-weakening effect on ores by high voltage electrical pulses based on single-particle tests , 2013 .

[25]  B. Lin,et al.  Experimental study on the microscopic characteristics affecting methane adsorption on anthracite coal treated with high-voltage electrical pulses , 2018 .

[26]  Xiaolong Zhang,et al.  Innovative utilization of refractory iron ore via suspension magnetization roasting: A pilot-scale study , 2019, Powder Technology.

[27]  Yuexin Han,et al.  Experimental Study on the Effect of Pretreatment with High-Voltage Electrical Pulses on Mineral Liberation and Separation of Magnetite Ore , 2017 .

[28]  Xingyang He,et al.  Compressive strength and hydration process of ground granulated blast furnace slag-waste gypsum system managed by wet grinding , 2019 .

[29]  K. Schönert.  Breakage of spheres and circular discs , 2004 .