A high-pressure water jet can break rock efficiently, which is of great potential to overcome the problems of a tunnel boring machine (TBM) in full-face hard rock tunnel digging, such as low digging efficiency and high disc cutter wear rate. Therefore, this paper presented a new tunneling method that is a TBM coupled with a high-pressure …
Berry et al. (1984) determined some rock properties such as compressive and tensile strength, Young's modulus, porosity and attempted to correlate these to the performance of a jaw crusher. Bearman et al. (1991) examined the relation between rock strength and power consumption and product size in crushing.
2.1 Energy. Rock drilling, blasting, and comminution (crushing and grinding) consume a vast amount of energy in hard rock mines. As mentioned in Sect. 1, statistics from hard rock mines indicates that drilling and blasting consumes 2% and comminution does 53% of the total energy input in the whole production chain from mining to mineral …
According to one estimate, the mining industry consumes 12EJ per year of energy – or 3.5% of total final global energy consumption.1 The energy intensity of …
The dynamic mechanical properties, crushing characteristics and energy consumption characteristics of rock materials can be studied by SHPB test, and more and more achievements have been produced ...
The dissipation energy of coal rock crushing also increases linearly with the impact velocity. There is no obvious regular change between the energy dissipation rate of coal rock and impact velocity during impact damage, and the dissipated energy of macroscopic crushing only accounts for 10~20% of the incident energy; most of the …
Abstract. The supply chain for metals used in manufacturing is usually from premanufacture (mining). Energy impact needs to be considered, with it being one of the …
Fractal energy consumption model of rock crushing. Fractal geometry was originally developed by Mandelbrot to describe highly irregular and self-similar objects (Mandelbrot, 1982); subsequently, fractal theory was applied to many other scientific fields (Perfect, 1997, Lai and Wang, 2015, Hu et al., 2016). In the field of rock fragmentation ...
The size reduction process of rocks plays a vital role in the quantity of desired product size with optimum energy consumption. The degree of rock …
In this study, the fractal fragmentation theory is used to describe the PSD of rock after crushing. The new surface theory is adopted to characterize the rock firmness; the firmness is directly proportional to the surface energy consumption (Bond 1955; Carpinteri et al. 2004)bining these two theories, a new index, f s, is …
Major energy sources for limestone and other crushed rock include fuel oil and purchased electricity. In 1992, rock mining consumed 66.8 Btu. Table 9-1 shows the type and …
To better understand and predict power consumption during the crushing stage and the product particle size distribution as a function of the CSS, feed size and rock strength, Bearman et al. (1991) performed pilot-plant scale experiments using a laboratory scale cone crusher. The authors drew some conclusions regarding the relationship …
Most of the costs in open pit quarry operations occur in crushing and grinding processes. Therefore, the management of crushing–grinding processes is very important. Many researchers investigated the effects of pile size distribution and specific charge values occurring as a result of blasting on crusher energy consumptions and …
6-10% savings in primary crushing costs measured by power consumption Processing The shot-rock is typically transported to the crushing plants using trucks. The large end users in the crushing plant consist of feeders, crushers, conveyors and screens. Figure 2 below shows the relative significance of the different electric energy users in a ...
For a rock of SG 2.65, Michaelson's equation is given as ... Apart from reducing wear, hard liners are essential to minimize crushing energy consumption by reducing the deformation of the surface at each contact point. The jaw plates are bolted in sections for simple removal or periodic reversal to equalize wear. Cheek plates are fitted to ...
Read more. Comminution, the process whereby rocks are crushed, grinded and cut into smaller parts, accounts for 56% of the mining sector's total energy usage, making it a major polluter. The process represents 3% of the world's generated electric power usage. To change this, a new competition has been launched by Natural …
Tosun and Konak (2014) measured power consumption of jaw crusher during crushing of limestone rocks. The specific crushing energy for the limestone rocks ranged between 1.012-3.298 ...
The result of this study can be used to obtain blast energy designs that consider comminution energy consumption and efficiency in the downstream rock-breakage processes. Concept of MTM.
As the rock comminution and energy efficiency can be defined as a function of area increment of particles in jaw crusher [41], the production of fines can be diminished by regulating the mf in the crushing chamber. From this point of view, feed level sensors or circuit breaker plugs may be beneficial for the regulation of mf during jaw crushing.
Among them, rock breaking specific energy consumption H w is an important indicator to measure the rock breaking performance of self-excited pulse jet, which is defined as crushing unit volume of rock the energy consumed, which characterizes the economics of rock breaking. The lower the specific energy …
The role of different blasting energy input on fragmentation is studied, and related to needs at the plant. The effect of different feed sizes on energy consumption in crushing and grinding is ...
The autogenous "rock on rock" crushing technique results in several major advantages, such as: product gradation remains constant, contamination rates are ... The diameter and the height of the rotor gives efficient and low power consumption crushing. The VSI consist of few wear parts which reduces downtime and stockholding. The ...
Table 9-1. Limestone and Other Crushed Rock Production and Energy Consumed by Type a Units 1987 1992 1997 Limestone and Rock Production b Billion tons - 1.2 1.2 Energy Consumption Coal Thousand tons Withheld 78.5 43.0 Fuel oil c Million bbl. 3.6 3.4 4.0 Gas Billion Cubic Feet 1.7 3.2 5.4 Gasoline Million Gallons 14.2 15.5 14.7 Electricity
Energy impact needs to be considered, with it being one of the five stressors that impact the environment. In this paper the energy needs for crushing and milling (comminution) are presented. A brief comparison is made with the energy needs for recycling of large scale waste products such as automobiles.
One such process is a crushing plant operation consisting of rock size reduction (comminution) and particle size separation (classification) processes. ... energy consumption and quality.
The aim of this paper was to determine the impact of physical and mechanical properties of rocks on the electricity consumption of a jaw crusher during crushing. This paper presents a different ...
The mode of energy consumption changes from climbing to shearing with an increase in vertical stress, considering the simulated results. ... Deng et al. applied fractal theory to theoretical analysis and experimental data on the energy dissipation of rock crushing. Zhang quantified the percentage of kinetic energy carried by fragments to the ...
Abstract. This paper presents the measurement and analysis of energy consumption of a laboratory jaw crusher during concrete recycling. A method was developed to estimate …
Guimaraes et al. (2007) found that energy consumption during crushing increases with increasing fines generation, because the energy required is proportional to the amount of new surface created. ... In the first crushing stage, 63–90 mm rock particles are crushed individually. In the second crushing stage, the product from the first …
For the sedimentary rocks (Siltstone) the specific crushing energy is approximately 1.26 kJ/kg. Tosun and Konak (2014) measured power consumption of jaw crusher during crushing of limestone rocks ...