ABSTRACT The study investigates the Hardgrove Grindability Index (HGI) values for binary blends of high-ash Indian coals and low-ash imported coals. The coals were selected in such a way that their grindability values were not closely spaced for studying the effect of blending in the HGI of coal blends. In addition, the coals were …
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This paper deals with the determination of chemical properties and hardgrove grindability index (HGI) of coal samples collected from three different coal fields of Punjab; Eastern Salt Range ...
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A higher Hardgrove index is equivalent with better grindability, but no proportionality exists between Hardgrove index and energy demand: H = 100 in no way means a double output when compar ing with H = 50. The most frequent H values are in the range 40-100. H = = 40 corresponds to 7.8%, H = 100 25% passing rate, i.e. the Hardgrove
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The Hardgrove grindability test, commonly used in coal characterization, was conducted on 13 Mississippian carbonates from Kentucky, Tennessee and Illinois. The results demonstrated that the grindability increases with a decrease in the SiO2/(MgCO3+CaCO3) ratio, with fine-grained and petrographically-complex stones …
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The Hardgrove Grindability Index (HGI) is a measure of coal's resistance to crushing. Grinding studies, and the resulting HGI, allow many different types of coal users to evaluate how coals will perform in their mills, allowing them to estimate grinding power requirements and throughput capacities.
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Experiments were conducted using standard Hardgrove equipment at Western Power's East Perth Laboratories. The coal seams or blends used for the experimentation are given in Table 1.The experiments comprised of 5 days of air-drying followed by oven drying (P2 seam, Hebe/P2/P4 coal blend samples for 3 h and P4, …
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ISO 5074:2015 specifies the method for determining the grindability index of hard coal using the Hardgrove machine. It also specifies the procedure for calibrating the test machine and for preparing the standard reference coal samples.
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The Hardgrove Grindability Index Primary Reference Material (HGI-RM) is a sample of coal used to calibrate instruments that are designed to determine the ease with which coal can be pulverized. The HGI value provides information for determining grinding power consumption and pulverizer capacities. The HGI-RM is prepared in a series of steps …
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Hardgrove grindability index (HGI) is a common procedure in coal analysis. The test fraction does not correspond to the whole coal, leading to a petrographic and …
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Hardgrove Grindability Index ( HGI ) from the experimental values of mass of the coal particles over 75-micron sieve has been introduced. Minor modifications have also been made in the diameter of the steel balls ... index of all types of Indian coals, excepting brown coals and lignites, using the Hardgrove machine. 2.
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Introduction. While the Hardgrove grindability index (HGI) is a long-established test for the evaluation of coals for combustion and, compared to many of the chemical tests of coal, the equipment is cheap and relatively easy to maintain, the test is inherently inaccurate owing to the simple fact that the test fraction is generally not …
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The Hardgrove grindability index HGI is closely related to the power consumed in crushing coal and may be used to optimize crushing in the coal-preparation shops at coke plants, as shown in [1][2 ...
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mass. The Hardgrove grindability is calculated for unoxidized (reduced) coking coal of different types (cor-responding to Ukrainian State Standard DSTU 3472:2015). Keywords: Hardgrove grindability index, coal characteristics, statistical assessment, coal classification DOI: 10.3103/S1068364X19010058 To assess the mechanical properties …
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1.1 This test method covers the determination of the hardgrove grindability index (HGI) of those petroleum cokes that contain no dedusting additive. The procedure for this test method is the same as in Test Method D409. Sections of this test method contain the significance and use of the HGI of petroleum coke, preliminary sample preparation ...
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ISO 5074:2015 specifies the method for determining the grindability index of hard coal using the Hardgrove machine. It also specifies the procedure for calibrating the test machine …
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The Hardgrove Grindability Index (HGI) is a measure of coal's resistance to crushing. Grinding studies, and the resulting HGI, allow many different types of coal users to evaluate how coals will perform in their mills, allowing them to estimate grinding power …
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Hard coal — Determination of Hardgrove grindability index 1 Scope This International Standard specifies the method for determining the grindability index of hard coal using the Hardgrove machine. It also specifies the procedure for calibrating the test machine and for preparing the standard reference coal samples.
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In Hardgrove test, grindability index is determined when a constant crushing pressure (29 kg) is applied over some constant weight of coal (50 gm) to grind …
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The Hardgrove Grindability Index (HGI) is a measure of coal's resistance to crushing. Grinding studies, and the resulting HGI, allow many different types of coal users to evaluate how coals will perform in their mills, allowing them to estimate grinding power requirements and throughput capacities.
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Standards: ISO 5074:1994 Hard Coal-Determination of Hardgrove Grindability Index ASTM D409-08 Standard Test Method for Grindability of coal by the Hardgrove-Machine Metho Spindle Speed RPM: 20±1 …
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Ore grindability is represented by the Bond work index value [6] and Mucsi et al. [5] have summarized the most widely known and utilized grindability tests as Bond, Hardgrove and Zeisel methods [7 ...
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In India, currently the annual coal demand is 800–900 million metric tons including 22% of imports from Indonesia, Australia, and South Africa for power sectors and nonpower sector industries. ... The study investigates the Hardgrove Grindability Index (HGI) values for binary blends of high-ash Indian coals and low-ash imported coals. The ...
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The Hardgrove Grindability Index Primary Reference Material (HGI-RM) is a sample of coal used to calibrate instruments that are designed to determine the ease with which …
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For coal, the Hardgrove Grindability Index (HGI) test was developed to characterize the relative grindability of a particular quality of coal relative to a pre-determined standard quality of coal (ASTM D409). The HGI test is an empirical batch method that simulates the continuous grinding and crushing operation of a ball, table or tube type of ...
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A very important aspect of proper preparation of the coal mixture for the coking process is its appropriate grinding. One of the parameters describing the energy input required for grinding is the Hardgrove index. This research was undertaken to determine the dependence of the Hardgrove grindability index on selected …
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Hardgrove grindability index (HGI) is the common parameter used to measure the grindability of coal. The smaller the HGI value, the coal is harder and …
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The Hardgrove grindability index represents a composite physico-mechanical property of the coal, embracing a number of specific properties such as hardness, strength, tenacity …
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PDF | Hardgrove grindability index (HGI) measures the grindability of coal and is a qualitative measure of coal. ... Hadapsar Industrial Estate, Pune 41 1 013, India. b. Department of Mineral ...
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1.1 This test method covers the determination of the hardgrove grindability index (HGI) of those petroleum cokes that contain no dedusting additive. The procedure for this test method is the same as in Test Method D409.Sections of this test method contain the significance and use of the HGI of petroleum coke, preliminary sample preparation …
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The resulting Hardgrove Grindability Index (HGI) provides a measure of the energy required in a grinding process or a measure of yield for given energy input. A prepared 50g sample of 6–No.30 sieve size coal and eight 1in (25.4mm) diameter polished steel grinding balls are placed in a stationary bowl having a machined circular track. An ...
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Hardgrove grindability index prediction using support vector regression ... Karnataka 583119, India article info abstract Article history: Received 4 August 2008 Received in revised form 30 ...
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