The Experts below are selected from a list of 69 Experts worldwide ranked by ideXlab platform
Paul Saylo - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a laboratory Rod Mill when grinding bituminous coal
Fuel, 2012Co-Authors: Hoo Lee, Mark S Klima, Paul SayloAbstract:Abstract Laboratory testing was conducted to evaluate the breakage of bituminous coal in a Rod Mill. A Pittsburgh seam coal, which had been obtained from the pRoduct stream of an operating coal cleaning facility, was used as the feed material. This material had an ash value of 6.7% and had been crushed to a nominal −6.35 mm. Grinding tests were carried out on a mono-size (2.38 × 1.68 mm) fraction. The tests were conducted using a 193.5 mm diameter and 245.0 mm long laboratory Rod Mill, which contained steel Rods at a volume loading of 23%. The Mill was operated at 70% of critical speed for various grind times. A locked-cycle test was also performed to simulate continuous grinding conditions. The grinding was characterized using the population (or size–mass) balance model. The breakage distribution and rates of breakage were determined from the grinding data. The results indicated first-order breakage. The locked-cycle results indicated that steady state was achieved in several iterations. The simulated results matched the experimental results very well.
Ketil Haarstad - One of the best experts on this subject based on the ideXlab platform.
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treating landfill gas hydrogen sulphide with mineral wool waste mww and Rod Mill waste rmw
Waste Management, 2014Co-Authors: Ove Ergerse, Ketil HaarstadAbstract:Hydrogen sulphide (H2S) gas is a major odorant at municipal landfills. The gas can be generated from different waste fractions, for example demolition waste containing gypsum based plaster board. The removal of H2S from landfill gas was investigated by filtering it through mineral wool waste pRoducts. The flow of gas varied from 0.3 l/min to 3.0 l/min. The gas was typical for landfill gas with a mean H2S concentration of ca. 4500 ppm. The results show that the sulphide gas can effectively be removed by mineral wool waste pRoducts. The ratios of the estimated potential for sulphide precipitation were 19:1 for Rod Mill waste (RMW) and mineral wool waste (MWW). A filter consisting of a mixture of MWW and RMW, with a vertical perforated gas tube through the center of filter material and with a downward gas flow, removed 98% of the sulfide gas over a period of 80 days. A downward gas flow was more efficient in contacting the filter materials. Mineral wool waste pRoducts are effective in removing hydrogen sulphide from landfill gas given an adequate contact time and water content in the filter material. Based on the estimated sulphide removal potential of mineral wool and Rod Mill waste of 14 g/kg and 261 g/kg, and assuming an average sulphide gas concentration of 4500 ppm, the removal capacity in the filter materials has been estimated to last between 11 and 308 days. At the studied location the experimental gas flow was 100 times less than the actual gas flow. We believe that the system described here can be upscaled in order to treat this gas flow.
Amiri M Paria - One of the best experts on this subject based on the ideXlab platform.
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rapid determination of bond Rod Mill work index by modeling the grinding kinetics
Advanced Powder Technology, 2013Co-Authors: R Ahmadi, M Hashemzadehfini, Amiri M PariaAbstract:Abstract Generally, Bond work index is a common method for selecting comminution equipment as well as estimation of grinding efficiency and calculating required power. In the current research, a simple, fast and accurate procedure is intRoduced to find the Rod-Mill work index based on the conventional Bond work index. The grinding experiments were carried out on four typical samples of iron, copper, manganese and lead–zinc ore with three test-sieves in specified time periods and aimed to shortening the procedure. Furthermore, the grinding kinetics and mass balance equations were applied to model the standard Bond Rod-Mill work index. For comparing the standard Bond Rod-Mill work index and the new modeled method, work index ( W i ) and pRoduced fine particles in a cycle ( G i ) for the four samples determined. The performed paired Student’s t -test results indicated that the Standard Deviation for G i and W i obtained by the shortened method are respectively 0.50 and 0.58 in respect of traditional Bond method.
Zhao Yongqing - One of the best experts on this subject based on the ideXlab platform.
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technique reformation of oil lubrication system of high speed wire Rod Mill
Steel Rolling, 2007Co-Authors: Zhao YongqingAbstract:The structure characteristics of lubrication system of high-speed wire Rod finishing Mill of Huaxi Iron Steel Co.was intRoduced.Meanwhile,the existing problems of pRoduction,such as frequency starting of spare pump,easy failure of filter,and high temperature of oil,were analyzed,and some countermeasures were put for ward.
James Spenik - One of the best experts on this subject based on the ideXlab platform.
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cfd simulation of entrained flow coal gasification coal particle density sizefraction effects
Powder Technology, 2010Co-Authors: Andrew Slezak, John M Kuhlman, Lawrence J Shadle, James SpenikAbstract:Abstract Computational Fluid Dynamics (CFD) simulation of commercial-scale two-stage upflow and single-stage downflow entrained-flow gasifiers was conducted to study effects of simulating both the coal particle density and size variations. A previously-developed gasification CFD model was modified to account for coal particle density and size distributions as pRoduced from a typical Rod Mill. Postprocessing tools were developed for analysis of particle–wall impact properties. For the two-stage upflow gasifier, three different simulations are presented: two (Case 1 and Case 2) used the same devolatilization and char conversion models from the literature, while Case 3 used a different devolatilization model. The Case 1 and Case 3 solutions used average properties of a Pittsburgh #8 seam coal ( d = 108 μm, SG = 1.373), while Case 2 was obtained by injecting and tracking all of the series of 28 different coal particle density and size mass fractions obtained by colleagues at PSU as a part of the current work, for this same coal. Simulations using the two devolatilization models (Case 1 and Case 3) were generally in reasonable agreement. Differences were observed between the single-density solution and the density/size partitioned solution (Case 1 and Case 2). The density/size partitioned solution predicted nominally 10% less CO and over 5% more H 2 by volume in the pRoduct gas stream. Particle residence times and trajectories differed between these two solutions for the larger density/size fractions. Fixed carbon conversion was 4.3% higher for the partitioned solution. Particle–wall impact velocities did not vary greatly. Grid independence studies for the two-stage upflow gasifier geometry showed that the grid used in the comparison studies was adequate for predicting exit gas composition and wall impact velocities. Validation studies using experimental data for the Pittsburgh #8 coal from the SRI International pressurized coal flow reactor (PCFR) at 30 atmospheres indicated adequate agreement for gasification and combustion cases, but poor agreement for a pyrolysis case. Simulation of a single-stage downflow gasifier yielded an exit gas composition that was in reasonable agreement with published data.
