The powder factor (specific charge) is the mass of explosives bei ng used (kg) to break a cubic meters volume of rock and is calculated using equation 3 below.
WhatsApp: +86 18838072829In blasting operations for removal of the overburden rocks, which have little or no inherent value, the powder factor is expressed in kg/m 3 [ 5 ]. Generally, the powder factor value varies from as low as to as much as kg/m 3 with kg/m 3 being the most common, in the open pit mines [ 6 ].
WhatsApp: +86 18838072829waste rock., for example, contain toxic substances like. heavy metals. that can leach into soil or water. Storing waste from mining causes land to degrade and the natural landscape to decline in health and quality. Coal mining, for example, contaminates water supplies and destroys natural habitats by its excessive production of dust and methane.
WhatsApp: +86 18838072829holes may be loaded. Threedimensional drillandblast software can pro. vide the designer with tools to interactively categorize. the blastholes that control how the holes are charged and ...
WhatsApp: +86 18838072829Powder Factor Powder factor (PF) dapat didefinisikan sebagai jumlah bahan peledak yang digunakan dibagi dengan volume hasil ledakan dalam satuan kg/ton atau kg/m3. Definisi lain dari powder factor adalah rasio volume ledakan dengan jumlah bahan peledak yang
WhatsApp: +86 18838072829Full size image. Draw the highwall at angle β, showing the cut width C, the overburden thickness D and the seam thickness T. Draw the two spoil heap faces at the angle of repose, θ, distance C apart. Draw the chain dotted line, xy, at distance = Dx, swell factor, above the base (pavement) of the seam.
WhatsApp: +86 18838072829article{osti_, title = {AMAX draglines dig more overburden with blast casting}, author = {Chironis, N P}, abstractNote = {Two of AMAX Coal Co.'s bestknown surface mines in the Midwest are blast casting to improve dragline productivity even though neither mine has pit conditions that are ideal for casting. The Delta mine at Harrisburg, Ill., and the Chinook mine at Brizil, Ind., are ...
WhatsApp: +86 18838072829The results showed that the optimum hole spacing was no more than m and the powder factor was no more than kg/m 3, and it proved that an effective casting percentage (ECP) of 34% could be realized. 1. Introduction Blastcasting practice in opencast coal mines is characterised by large blast hole diameter and large charges.
WhatsApp: +86 18838072829PT Pacific Global Utama is a company engaged in the coal mining industry. ... plane orientation adalah dip out of face dengan nilai powder factor 0,118 kg/m3. ... material overburden yaitu ...
WhatsApp: +86 18838072829total required drilling, powder factor, and delay times. ANFO and emulsions are the most common explosives agents used in WV surface coal mines, and they are considered in this study. The total drilling and blasting cost is determined. In module III, production rates for hydraulic shovels, electric (rope) shovels, and frontend wheel loaders are
WhatsApp: +86 18838072829Overburden removal is a major activity of surface coal mining and accounts for over 6070% of the costs. Cast blasting is integral to overburden removal using draglines.
WhatsApp: +86 18838072829Highwall mining is a coal mining method for recovery of outcropped coal by mechanical excavation without removal of overburden. A continuous miner with single or multiple ... other factors. Figure 2 shows a comparison of the annual produ ction rates and producti vities of US coal mines. Surface mines have very few limitations on the operation ...
WhatsApp: +86 18838072829One way of overburden dismantling in Pit 2 Banko Barat's by drilling and blasting methods. Blasting at PT. Bukit Asam uses actual blasting geometry on average that's used in diameter 200,03 mm, burden 6,0 m, space 7,0 m, stemming 4,8 m, depth of explosive hole 7,0 m, and column height 2,18 m with powder factor 0,12 kg/bcm.
WhatsApp: +86 18838072829Blasting in Overburden is mainly done either to fragment and shatter the rock or to displace the rock in the mine area by casting of Overburden. According to explosive rules the explosives and their accessories are classified into eight classes. ... (power gel B Navashakti ) 17 Powder factor(o/b coal) O/B2,6ccm, 18 Stemming ...
WhatsApp: +86 18838072829In mining, overburden (also called waste or spoil) is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Spoils. waste material brought up during the course of an excavation or a dredging or mining operation. Open pit mining.
WhatsApp: +86 18838072829changing the powder factor. The average burdentocharge diameter ratio of 25 to 30 is for average density rocks similar to the typical rocks listed in table 191. Denser rocks such as basalt require smaller ratios (higher powder factors). Lighter materials such as some sandstone or bituminous coal can be blasted with higher ratios (lower ...
WhatsApp: +86 18838072829In this light the present study was conducted in opencast coal mines to see the effect of Schmidt ... Powder factor, Schmidt hammer, Rebound number, Rock mass, Overburden bench *** 1. INTRODUCTION Rock mass comprises several different rock types and is affected by different degrees of fracturing in varying stress ...
WhatsApp: +86 18838072829Higher powder factor causes oversize and lower powder factor results in crushed rock. Mean fragment Joint plane orientation and spacing size was plotted against the powder factor for 91 blasts of coal overlying overburden benches, as presented in Fig. 22.
WhatsApp: +86 18838072829powder factor causes oversize and lower powder factor results in cru shed . ... blasts of coal overly ing overburden benches, as presented in Fig. 22. The . general trend shows tha t, ...
WhatsApp: +86 18838072829Overburden at a coal mining site. In mining, overburden (also called waste or spoil) is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Overburden is distinct from tailings, the material that remains after economically valuable components have been extracted from the generally ...
WhatsApp: +86 18838072829thickness of overburden coal seam thickness ground control surface protection requirements • Entry and crosscut widths generally range from 15 to 25 feet • Pillar sizes will generally range from 30 to 100 feet and have a rectangular configuration • Extraction Ratio is the ratio of coal removed compared to estimated in ...
WhatsApp: +86 18838072829FACTORS CONTROLLING THE DUMP FAILURES BASIC CONCEPT OF DUMP SLOPE STABILITY STUDY AREA PRECAUTIONS TAKEN FOR DUMP FAILURES 4 5 5 6 9 11 ... The removal of overburden is the first step in a coal winning operation, so as to expose underlying coal for excavation. The overburden material being a waste and nonmarketable
WhatsApp: +86 18838072829blasting process measures like the powder factor, the charge length, the amount of explosives used per charge (blast) will be considered and the overburden fragment size will be determined to improve productivity and cost. ... overburden removal. Coal mining processes (in sequence) Top soil removal
WhatsApp: +86 18838072829Coal is a black or brownishblack sedimentary rock that can be burned for fuel and used to generate electricity. It is composed mostly of carbon and hydrocarbons, which contain energy that can be released through combustion (burning). Coal is the largest source of energy for generating electricity in the world, and the most abundant fossil fuel ...
WhatsApp: +86 18838072829In this light the present study was conducted in opencast coal mines to see the effect of Schmidt hammer rebound number or transformed compressive strength of rocks on powder factor. The correlation was found sufficiently reliable to enable the determination of optimum powder factor for surface bench blast in different rock types maintaining ...
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