Optimization of discharge condition for recycling aggregate by pulsed discharge inside of concrete

Wang, D.; Inoue, Shinichi; Araki, J.; Aoki, Takahiro; Maeda, S.; Iizasa, S.; Takaki, M.; Namihira, T.; Shigeishi, Mitsuhiro; Ohtsu, Masayasu; Akiyama, H.

doi:10.1109/ppc.2009.5386153

Cited by 3 publications

(5 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A number of studies which investigated the feasibility of liberating concrete with electrical comminution for the recycling purposes have been reported (Bluhm et al, 1997(Bluhm et al, , 2000Frey et al, 2002;Fujita et al, 2001a;Menard et al, 2011;Inoue et al, 2009;Wang et al, 2009). This paper applies the same technique for a different purpose -to study the effect of electrical breakdown channel locality.…”

Section: Synthetic Samplesmentioning

confidence: 99%

Electrical breakdown channel locality in high voltage pulse breakage

Zuo¹,

Shi²,

Manlapig³

2014

Minerals Engineering

View full text Add to dashboard Cite

Section: Synthetic Samplesmentioning

confidence: 99%

Electrical breakdown channel locality in high voltage pulse breakage

Zuo¹,

Shi²,

Manlapig³

2014

Minerals Engineering

View full text Add to dashboard Cite

“…1 V c is the charge voltage of the pulser, which is approximately equal to the peak voltage of the output pulse. 2 Total number of shots includes those at voltages less than V b . 3 E n calculated using methods described in paper.…”

Section: Resultsmentioning

confidence: 99%

“…In the second process, the electric current flows through the rock, preferentially along mineral grain interfaces that induce tensile and branching cracks at the boundary interfaces, either by heating and differential expansion or by a shock wave induced by the electrical impulse itself. Both processes have been examined experimentally on rock and concrete by multiple researchers [1][2][3][4][5][6][7][8][9][10][11][12][13]. However, the electrofracturing process has not previously been systematically evaluated at elevated pressures.…”

Section: Introductionmentioning

confidence: 99%

Electrofracturing of Shale at Elevated Pressure

Bauer,

Glover,

Williamson

et al. 2024

Energies

View full text Add to dashboard Cite

Electrofracturing deeply buried shale formations could be used to increase reservoir permeability and improve reservoir production without requiring large volumes of freshwater. This paper describes a novel experimental system and initial test results to electrofracture shale under high confining pressures. Core-scale laboratory testing was performed on twelve rock samples recovered from a shale gas reservoir. Each sample was subjected to confining pressures of 20.7 MPa (3000 psi) or 58.6 MPa (8000 psi), representative of overburden pressures at depth. Samples were then subjected to application of high voltage until specimen fracture. The experiments produced deformed samples with multiple fracture types, both parallel and oblique to bedding planes. Electrofracturing increased permeabilities by up to nine orders of magnitude for extended time periods. Rock fracture and throughgoing fractures were demonstrated. Computed tomography images revealed the creation of fractures and tube/tunnel flow channels, which resisted closure under hydrostatic pressures up to 58.6 MPa. The breakdown energy and permeability changes in the sample were independent of applied confining pressure. The cumulative energy input required for fracture depended on applied confining pressure and sample length. The energy required to fracture samples up to 9 cm in length is generally more than 0.5 kJ/cm, but no greater than 1 kJ/cm. Our results show that electrofracture of shales under confining pressure is possible and could be a possible water-free mechanism for reservoir stimulation.

show abstract

“…A number of studies which investigated the feasibility of liberating concrete with electrical comminution for the recycling purposes have been reported ( (Bluhm et al, 1997;Bluhm et al, 2000;Fujita et al, 2001a;Frey et al, 2002;Aoki et al, 2009;Araki et al, 2009;Inoue et al, 2009;Wang et al, 2009;Menard et al, 2011). This paper applies the same technique for a different purpose -to study the effect of electrical breakdown channel locality.…”

Section: Synthetic Samplesmentioning

confidence: 99%

“…In both of these two comminution methods, tensile stress is the component predominating in the disintegration process. As a result concrete grout can also be used to model rock like behaviour in electrical comminution.The applicability to disintegrate concrete particles with electrical comminution had also been confirmed by a series of studies which aims to investigate the feasibility to liberate concrete with electrical comminution for recycling purpose (Bluhm et al, 1997;Bluhm et al, 2000; Chapter 3 Experimental Details 44 2001a; Frey et al, 2002;Aoki et al, 2009;Araki et al, 2009;Inoue et al, 2009;Wang et al, 2009;Menard et al, 2011). …”

mentioning

confidence: 95%

A study of the applications and modelling of high voltage pulse comminution for mineral ores

Zuo¹

View full text Add to dashboard Cite

The pre-treatment of ore particles by high voltage pulses (HVP) at low specific energy has a potential to reduce the energy consumption and operation costs. Nevertheless, the influencing factors and the behavior of HVP breakage of ore particles have not yet been fully understood. The overall objective of this thesis is to study the applications and modelling of HVP breakage by understanding the behaviour of ore particles subjected to pulse discharge. The three areas investigated are:1)The effects of mineral properties on HVP selective breakage and the application of this selective breakage in ore pre-concentration.2) The methods to evaluate and to characterize HVP breakage results. 3)Modelling ore particle behavior in HVP breakage.In this project, the selectivity of HVP breakage is studied using synthetic samples made of construction grout and pyrite grains. The result confirms that the breakage response of particles is dominated by the locality of electrical breakdown channel. The electrical breakdown channel locality is controlled by the grains of minerals with high conductivity/permittivity and their location in a particle. This understanding has led to the discovery of a novel technique for ore preconcentration using high voltage electrical pulses. The technique utilises metalliferous graininduced selective breakage, under a controlled pulse energy loading, and size-based screening to separate the feed ore into two products for splitting of ores by grade.To evaluate HVP breakage results, a t 10 -based model was developed to predict the degree of impact breakage, t 10 , of pulse-treated particles from that of untreated particles. This model incorporates only one parameter, C Ab , which is equivalent to percentage change of A×b values. The t 10 -based model can be used to assess energy reduction due to the pre-weakening effect in the downstream mechanical comminution process. A Wide-size JKRBT characterisation method was created, initially for quick determination of breakage characteristics of the HVP product; ultimately for use as an express ore breakage characterisation method. In this method, particles in wide size range are tested as one size class in the JKRBT by single-particle breakage mode, significantly simplifying the feed particles preparing and product sizing procedures. A conceptual design of an on-line ore ii competence measuring system based on this principle is proposed. Both the t10-based model and the Wide-size JKRBT method utilise a size-dependent breakage model previously developed by the JKMRC.Behaviour of ore particles in HVP breakage was investigated with a pilot scale and a laboratory scale HVP breakage devices. The effects of specific energy, pulse voltage, cumulative discharges, feed particle size and ore particle breakage pattern (body breakage or surface breakage) were investigated. Based on the data, a model structure for HVP breakage was developed, which incorporates four sub-models using the similar structure to predict four HVP breakage indices: body breakage probability...

show abstract

Optimization of discharge condition for recycling aggregate by pulsed discharge inside of concrete

Cited by 3 publications

References 2 publications

Electrical breakdown channel locality in high voltage pulse breakage

Electrical breakdown channel locality in high voltage pulse breakage

Electrofracturing of Shale at Elevated Pressure

A study of the applications and modelling of high voltage pulse comminution for mineral ores

Contact Info

Product

Resources

About