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By W. L. Han, Y. D. Zhang, X. C. Li

Meta-systhetic technique for large systems engineering has been placed on the agenda. The meta-systhetic A1 approach should involve the integration of digital and knowledge info, from qualitative to quantitative analysis, etc. Some algorithms of meta-systhetic technique such as ANN-ES and GA-ANN are introduced. A case study follows - mining conditions evaluation by meta-synthetic A1 methods, including: setting up the structure of evaluation indexes system, deciding their grade of membership by ANN-ES algorithm; determining the weight values of evaluation factors by GA-ANN algorithm; and developing the integrated evaluation model.

Jan 1, 2002

By V. V. Ershov

Application of computers in the study of mineral deposits pursues two main objectives: 1. obtaining reliable information on the properties of the orebody; 2. providing graphic presentation of this information for its optimal use. These problems are successfully solved if, during preparation of graphic computer software, we apply modern mathematical methods. The present paper treats the problems of using geostatistics for graphic modelling of deposits by means of graphic computers. It should be noted that in this field geostatistical methods may be used for: a) indices evaluation in the nodes of regular grid, or in given blocks, by means of kriging, for its designated purpose; b) for evaluation of accuracy of interpolation methods, traditionally used in computer graphics, and not being optimal.

Jan 1, 1986

By Paul W. Patton, Christopher Scott Smith

The use of ceramic-in-rubber pulley lagging on bulk material belt conveyors is increasing. Many of the applications have been on pulleys originally installed with rubber lagging. There is a consensus that the fiction characteristics of the ceramic material are significantly better but the factors quoted vary, possibly because the more complex traction mechanism of the dimpled ceramic elements on the belt is not well understood. In this paper we will report and evaluate field data from a number of field installations to provide a study of actual friction characteristics in successful applications for those who desire reliable data for using ceramic-in-rubber lagging in new conveyor designs.

Jan 1, 2004

By C. M. Brown

Common operating philosophies and objectives of mining and mineral process operations are discussed. Key information required to effectively monitor operations is reviewed in conjunction with the impact of external variables such as commodity price changes on strategies adopted.

Jan 1, 1991

By Herbert E. Allen, Andrew F. Kingery, Spyros P. Pavlou

This paper examines and compares the role that chemical speciation plays in the environmental aquatic toxicity of two metals - copper and arsenic. Copper is shown to have well-understood chemical speciation equilibria, but poorly known species toxicities. Arsenic presents the opposite case, with unpredictable speciation in aquatic systems, but is relatively easy to evaluate toxicologically. Speciation is not currently incorporated into Water Quality Standards. This can have a major impact on the cost of environmental containment and cleanup.

Jan 1, 1992

By Yong-ping Wu

Based on the rules of strata behavior and the characteristics of rock movement, the elementary problems of using fully mechanized coal mining techniques in steeply dipping coal seams are described. A model of the "surrounding-support-rock" relationship is made. The support systems stability during fully mechanized mining of steeply dipping coal seams is studied. Then, a practical engineering example of the fully mechanized mining of a steeply dipping seam is presented. The seam used in the example is in the Lushuidong colliery, which is administrated by Huaying Mining Bureau, Sichuan Province.

Jan 1, 2003

By W. E. Threlkeld, J. A. Treacy, L. J. Stewart, J. C. Ruckmick

The Mustang Draw sulfur deposit is developed in a dolomite reef complex in the Permian San Andres Formation on the eastern margin of the Midland basin in Glasscock County, Texas. Interpretation of the genesis is dependent upon coincidence of a NE-trending fault system with the NW- trending reef complex. The reefs, reef talus, and oolites contained up to 30% interstitial anhydrite. It is indicated that artesian ground waters, hydrocarbons, and bacteria circulated into the reef complex along the fault zone. Bacterial consumption of hydrocarbons and anhydrite created extensive porosity, permeability, and deposition of sulfur in vugs and cavities, and along fractures in the dolomite.

Jan 1, 1992

By Z. T. Bieniawski

After many significant advances in mining, including development of sophisticated methods for strata characterization and numerical modeling analyses, the engineering design process in mining strata control is as primitive as it was two decades ago. Yet, major advances in design methodologies have occurred in other branches of engineering. Is creative design in mining a myth only? Are we deluding ourselves when we talk about innovative mining design of today? Did you know that most design experts are often unaware of their own decision-making processes? This paper explores the methodology of creative engineering design as a new recognized discipline.

Jan 1, 1987

By William E. Little, William R. Sharp, Edward R. Kennedy

Cost o f mechanical tunneling requires the knowledge of many machine/rock parameters such as rock types, machine power, penetration rate, cutter life, maintenance schedule, etc. Capital investment, labor requirements, and project scheduling will all play an important role in defining the economics of the overall project. Knowledge of the cost sensitivity of different project parameters will improve the overall success of any particular tunneling project if this information is incorporated into an effective management plan. Through the use of an interactive graphic computer program written for a microcomputer, one has the ability to quickly evaluate relative costs for a variety of parameters for either an existing project or for a proposed site.

Jan 1, 1983

By Anthony G. Grice

This paper discusses the contribution that backfill is making to the Australian mining industry and provides some information on the largest operations together with some novel applications. Each of the three major backfill types; hydraulic, rock and paste are discussed in turn with a focus on new ideas and advances in understanding, technology and operating practices.

Jan 1, 2001

By Harold L. Kike

Until recently sulphur uses were so broadly based that economists used sulphur consumption to measure industrial activity. However, sulphur use patterns are changing and the manufacture of phosphate fertilizers presently accounts for approximately 65% of the world's sulphur consumption compared with only 25% in 1960. This has encouraged the development of new agricultural and industrial uses for sulphur. Major emphasis has been placed on its use as a fertilizer and in the manufacture of paving materials, specialty concretes and coatings. Some of these uses could have a significant impact on future sulphur usage.

Jan 1, 1986

By Wang Yingmin, Xu Zhuyun

The optimum of general mine ventilation networks is very difficult and has a considerable significance. Based on the content model, this paper presents a more general nonlinear programming model whose number of variables equals that of independent meshes. The constrained conditions are linear inequalities only. The model is changed into an unconstrained problem with multiper method. The optimum results are computed with DFP algorithm and the Improved Golden section method is used in its linear searching. The computer program written in Quick BASIC is suitable to the optimum of any type of large mine ventilation networks with different regulating devices. The paper presents two examples for optimum of ventilation networks.

Jan 1, 1991

By E. Forssberg, Y. Zeng

Fine crushing and rod grinding have been investigated using a laboratory-scale jaw crusher and a rod mill. The net energy consumption in both crushing and grinding was evaluated from torque measurements. An empirical relationship was established between energy consumption, particle size and operating parameters. When the mill feed size is reduced, through fine crushing, to about 80% passing 3 mm, the energy consumption will be minimized in a comminution chain of fine crushing and coarse rod grinding. The results in fine crushing were compared with a large-scale test.

Jan 1, 1993

By Ji Changsheng

In a large surface mine design, different kinds of mining equipment can be selected. Even though the major purpose of capital investment is to get more profit from mining activities, there are some other complicated factors which influence the selection of mining equipment must be considered as well. A fuzzy evaluation model with fuzzy set theory is proposed in the paper to make a good selection of mining equipment in which different kinds of factors including quantitative and nonquantitative ones can be taken into account at the same time. With the model, mining equipment selection of a large surface mine can take into consideration not only economic factors but also some other factors which play important role in mining system.

Jan 1, 1996

By P. R. A. Andrews, G. Heinrlch, V. I. Lakshmanan

The paper describes a simplified method to chemically modify the surface of industrial mineral fillers. Four industrial mineral samples were taken from feedstock of commercial fine grinding operations. These samples were ground in bench scale ball mills and in the presence of various organic solvents. The ground products were measured for particle size distribution, surface area, surface chemistry by oil absorption and degree of organicJminera1 bonding. Where appropriate, the ground products were compared to commercially available surface modified, industrial mineral fillers.

Jan 1, 1990

By Fathi Habashi

ION FLOTATION was introduced by F. Sebba in 1959. This technique permits the recovery of metal ions from solution through the introduction of an appropriate cationic or anionic surface-active agent into the solution. The surface-active agent, called a collector, is added in stoichiometric amounts in relation to the metal content of the solution. It reacts with the metal ion to form an insoluble soap, and is levitated to the surface by gentle bubbling of air to form a foam which collapses into an insoluble scum. The optimum conditions for the ion flotation with soaps of C10-16, fatty acids are shown in Table 15-1. Baarson and Ray (1965) found that once the metal was completely precipitated as the hydroxide, as little as one hundredth the stoichiometric amount of the collector was required to cause complete flotation of the [ ]

Jan 1, 1970

By Liang Ruilu, Guo Lihua

In light of the properties on process mineralogy of the old tailings in a certain copper mine in the People's Republic of China, a new process of combined reagent and stepwise flotation is applied in which the flotation of copper sulfides is followed by the flotation of copper oxides. Recoveries of copper and associated gold and silver have been greatly increased. The tailings obtained were subjected to the gravitational separation-magnetic separation process to recover iron minerals. Tailings from iron separation are taken as fillers and sent to the pit underground. Thus, the secondary resources are comprehensively utilized.

Jan 1, 1995

By R. Brough, T. K. Moller

There are differences in design aspects between steel and rubber linings in grinding mills. This paper describes the basic design rules for rubber liners for different grinding applications. When converting a mill from steel to rubber liners, the design must be changed from such familiar steel liner shapes as wedge bars and plates, wave liners, and ship-lap, to take advantage of the characteristics of rubber. Very little of the knowledge of the wear properties of steel can be used for the design of rubber mill liners.

Jan 1, 1990

By P. E. Sarquis, R. Lenzo

The concentration of barite by gravity separation generates substantial quantities of fine particle wastes, and it is estimated that =40% of the contained barite is lost to these waste streams. In this study, froth flotation was examined as a potential method for the recovery of fine-barite particles. The study included the use of kinetic equations to estimate the variables affecting flotation, batch-scale rougher flotation tests to study the flotation variables and an examination of alternatives for the cleaning of the rougher concentrate. Results indicated that a concentrate grade of 96.5% could be achieved with a recovery of 77.5%. Although barite flotation from industrial wastes is more difficult than direct barite flotation, the process has considerable economic potential.

Jan 1, 1996

By Bo Forsman

The computer program SYGRISIS estimates number of units of equipment and operating costs on the basis of yearly production for different loading (wheel loader, LHD, digging arm loader) and transport (truck, train, conveyor belt, hoist, pump) equipment either individually or in any specified combination. Input data are yearly capacity, working time and technical data for the equipment. For the cost analysis input data are technical quantities and unit costs. SYGRISIS is written in TURBO Pascal and can be used on IBM compatible PCs with MS-DOS operating system.

Jan 1, 1989