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By Carlo Sampaio, Moacir Veras, Aaron Young, Carlo Petter

"Three major challenges for the mining industry are the minimization of energy use, water consumption and environmental impact. Therefore, any technique that reduces milling waste, decreases water usage and shrinks impact during mine life must be considered a major innovation in mining.To these ends, one of the most impactful developments in mining within the last 10 years has been the expanded use of high technology sensors to create preconcentrations of mine ore (Jönsson, 2014). The most common sensors used are charge-coupled device (CCD) cameras, that allow through a red, green and blue (RGB) coloring system, the separation of minerals with different colors, tones and, in many cases, with differences in brightness.More recently, the development and use of dual energy X-ray transmission (DE-XRT) to enable the separation by atomic density of the constituent minerals within a given rock has become a reality. Within this work, a rapid bibliographical review of the CCD and DE-XRT methods and examples of their usage within mining and the industrial minerals sector are presented.Sensor-based sorting in miningAutomation within mining is one of the industry’s current goals. Sensors of various kinds have been used as steps toward automation in recent years, from improving the safety and productivity of haul trucks through the use of cameras and global positioning satellites (GPS), to the divination of slope failures. Just as with other mining areas, sorting has improved dramatically and made great steps toward automation in recent years (Wotruba et al., 2014).Sensor-based sorting (SBS) uses spectromatic sensors to identify intrinsic characteristics of particles and separates them by either mechanical or pneumatic means into different product streams (Wotruba et al., 2014). SBS can be used with great effectiveness to improve gravimetric beneficiation through the selective separation or preconcentration of run of mine ores (ROM)."

Jan 1, 2015

By R. J. Wesely

In recent years the trend in copper smelting has been to expand existing smelters to increase their throughput. New smelters under consideration are large, typically in excess of 200,000 tons per year of copper. Despite this trend to larger smelters there are a number of conditions where a much smaller smelter can be economically viable. This paper examines these conditions and outlines the process concepts for a small smelter treating from 20,000 to 100,000 tons per year of copper.

Jan 1, 2000

By S. J. Ma

With the very effective depressant and collector developed by China Bluestar Lehigh Engineering Corp (hereinafter referred to as LEHIGH), satisfied results are obtained from laboratorial beneficiation tests on phosphate samples from Karatau, Republic of Kazakhstan by the direct flotation process. In this paper the effect of single factors on performance of flotation is studied and their applicable ranges are proposed. The final test results are described as follows: As the feed contains 23.20 % P2O5, and 3.96% MgO, a phosphate concentrate assaying 29.77%P2O5 and 1.54% MgO is produced, and the P2O5 recovery in concentrate is 88.28%. The beneficiation tests make it possible to simplify existing technology with fine grinding-desliming, followed by reverse & direct flotation system and consequently improve the concentrate grade and recovery for the future beneficiation plant

Jan 1, 2014

By K. Fair

Using an agitated column 203 mm (8") diameter by 1829 mm (72") tall with independent agitation units for the gas dispersion zone and the collection zones, respectively, permitted the independent evaluation of the attachment and the detachment mechanisms for the chalcopyrite/ silica system. Three particle size fractions were used in this study, i.e. coarse (+75 µ m), intermediate (-75 µ m + 10 µ m) and fines (-10 µ m). The optimum selection of the two agitation zones for the three particle size fractions were determined as a function of grade, recovery, residence time and air superficial gas velocity.

Jan 1, 1990

By M. Etelapaa

A new approach to controlling the process of selective flotation of sulphide minerals from pyrite in a lime environment is covered in the presentation. Advantages of process control based on the electrochemical potential of slurry controlled by ?? ? electrode are proved and compared to conventional methods of ?? ? metering and conductometry. Keywords: flotation, electrochemical potential, automation dosing system, neural network

Sep 1, 2012

By Zachery Zanetell

Flotation circuit performance has become increasingly more challenging due to the complexity of available ore sources. To optimize value mineral recovery, the mineralogical composition of the ore should be evaluated and understood. Utilizing a variety of mineralogical and analytical tools, flotation processing challenges can be overcome and potential limitations understood. In this paper, several case studies will be discussed in terms of the value that has been provided through the use of mineralogical analysis to optimize flotation performance.

By D. Malhotra

Most primary-molybdenite producers use a selective-flotation process in which molybdenite is floated from the ore while other sulfide and non-sulfide gangue minerals are depressed in the same step (Figure 1). The process was developed at the Climax mill. Reagents used in the rougher-flotation stage include vapor oil (collector), syntex (surfactant), pine oil (frother) and occasionally sodium cyanide and Nokes reagent (depressant). Rougher concentrate is upgraded by cleaner flotation to produce market-grade molybdenite concentrates. Reagents used in the cleaner flotation stage are Dowfroth 250, vapor oil, sodium cyanide and Nokes reagent. The development of the flotation reagent scheme at Climax and the role of the reagents have been well described by Born, et al, (1976) and Malhotra, et al, (1976, 1977a, 1977b, 1977c, 1980). The hydrocarbon collector, vapor oil, accounts for approximately 50 percent of the total molybdenite-flotation reagent cost. Because vapor oil sources are limited, and the cost of vapor oil has increased significantly over the last decade, several studies have been done to evaluate alternate oil-based collectors and/or blends of collectors which would produce similar metallurgical results at a reduced cost, or increase the overall molybdenite recovery at the same cost (Smit and Bhasin, 1983; Hahn, 1969; Smith and Bhappu, 1971). The approach taken in the present study was to evaluate alternate non-oil based collectors and collector systems that are less expensive than vapor oil.

Jan 1, 1985

By W. Lodge, G. Rasmussen

"The carbon-in-pulp (CIP) process has been the dominant gold recovery technology since the 1980s. During all this time carbon measurement, and control of the carbon transfer pumps has been largely manual in nature. Such manual operation inevitably limits process efficiency, potentially resulting in higher gold solution losses, and higher cost of circuit operation. Based on the authors’ experience, average plant solution loss is in the range of 0.02-0.03 ppm Au, as opposed to the general industry target of 0.01 ppm Au or less. Gekko Systems, in conjunction with Curtin University’s Gold Technology Group, has developed a carbon concentration meter, the ‘Carbon Scout’ meter. The meter automatically measures carbon concentration in all tanks, providing more frequent and more precise data. Combined with SIMCIL, a CIP circuit process model which is used to determine the optimum set points for the circuit, the meter should ensure lower gold solution losses, and more efficient operation of the carbon circuit. This paper will review they critical factors for good carbon management, the development of the meter and results from the first plant installation. Additional benefits of the Carbon Scout, including improved health and safety and the opportunity to measure other key variables in the leach/adsorption circuit from one central location will also be described.INTRODUCTION The carbon-in-pulp (CIP) process was first introduced to the gold industry in the early 1950s at the Carlton Mill in the USA (Fast, 1988), with the modern version of CIP becoming fully developed with large scale installations in South Africa in the late 1970s (Laxen, 1982). CIP quickly became the technology of choice for new operations, and for the retrofitting or upgrading of existing operations. In the 1980s the carbon-in-leach (CIL) circuit configuration became the process design of choice due mainly to its lower capital costs. With 40 years of operational experience, CIP/CIL for gold recovery is now mature a technology, whose operations and limitations are well understood. To extract further efficiencies from such technologies, by improving recoveries and/or reducing operating costs, is challenging and may require new approaches to circuit management. Gekko Systems, in association with the Gold Technology Group at Curtin University, has developed the Carbon Scout, an automated carbon measurement device. This device replaces manual measurement of carbon concentration in carbon adsorption tanks, providing more frequent and more accurate data for control of the CIP process. Data from the Carbon Scout can be used to automatically control the carbon forwarding pumps."

Jan 1, 2018

By Y Zhou, Y Liu, J-P Yang, P Wang, K Hu

"Large-scale mine reclamation has taken place recently in response to the implementation of mining regulations in China. Effective monitoring of the progress of reclaimed land is a critical procedure to assess the quality of reclamation program and to ensure that mining enterprises fulfill their reclamation responsibilities. The present paper reports a preliminary study that examines the situation of mine land reclamation monitoring. Based on the monitoring, some general requirements for mined land reclamation have been proposed, including: the monitoring should be systematic and comprehensive the monitoring should be adapted to specific local conditions the monitoring should be reasonably optimised via scientific methods and technology the monitoring should stick to a variety of national technical criteria.The aim of land reclamation monitoring is to evaluate changes of critical indicators closely reflecting the development trend of the reclaimed mined land, to develop or improve the criteria and technical parameters specific to the site, and to prevent secondary environmental degradation. Based on these requirements and aim, the monitoring should cover the progress of reclamation, establishment of vegetation and plant community development; and recovery of land and water quality in the reclamation area. Regulatory measures are proposed which would improve the work of mine reclamation monitoring in terms of regulation, organisation and financial support.CITATION :Wang, P, Yang, J-P, Zhou, Y, Hu, K and Liu, Y, 2012. The primary framework for the mechanism of the mine reclamation monitoring in China, in Proceedings Life-of-Mine 2012, pp 47-50 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

By J. E. Golsan

Barrick Gold Corporation installed an expert style control system on the grinding circuit at its Mercur mine. Barrick's main objective was to increase mill throughput by a minimum of 3%. The expert system team collected operating data and then created a knowledge base using Comdale/X expert system development software. The expert system moved from on-line "advisory" mode, testing of expert rules, to full process control in four weeks. Expert system control benefits include a 9-15% increase in mill throughput, consistent mill loading leading to less wear on SAG mill parts, and improved downstream process control.

Jan 1, 1998

By AIME AIME

AT a joint meeting of the Tulsa Geological Society and the Mid-Continent Section of the A; I. M. E., held at Tulsa on March 21, the history of unit development in the Kettle- man Hills field was discussed. Robert C. Patterson? Super- visor for the U. S. Geological Survey at Taft, Calif., was the speaker. An abstract of some of his remarks follows: On July 1, 1923, curtailment agreement for two years was made between the operators of North Dome Kettleman and the U. S. Department of the Interior. In this it was agreed to consider a plan of unit development, or other cooperate method of developing the structure. As a result, Kettleman North Dome Association was incorporated in December, 1930, as a non-profit cooperative corporation under the laws of California. Approved in January, 1931, by California Oil and Gas Supervisor and by Secretary of Interior. On Feb. 10, 1931, it became an active organization through election of executive officers and eleven- directors. General manager chosen. Association started to function April 1, 1931. Assumed control of 10,800 acres of proved and semi-proved land, as shown in Table 1.

Jan 1, 1932

By John T. Ryan

DEFINITE improvement in its accident fatality rate in the coal-mining industry was recorded during 1941, based on preliminary figures for the period from January through October. Total production during this ten-month period was approximately 91 percent of the total production in all of 1940. The ten-month accident rate for both bituminous and anthracite mining in 1941 was 2.15 killed per million tons of coal mined, compared with a rate of 2.66 for the full year of 1940. The bituminous rate decreased from 2.55 in 1940 to 1.99 in ten months of 1941, and the anthracite rate from 3.62 to 3.53 in similar periods. The decrease is more apparent for the bituminous branch of the industry, as the high figure in 1940 was due to seven major disasters which brought death to 276 men. The same number of major explosions during ten months of 1941 caused only 64 lives to be lost. The severity of the explosions has been lower this year but a definite need still exists for reduction in this type of accident.

Jan 1, 1942

By C. E. Williams

THE Iron and Steel Division, A.I.M.E., is unique in this country in that it serves all phases of the iron and steel industries. Through its publications, its meetings, and its sponsorship of new technical developments in the industries, it has proved of great value. The various technical committees of the Division are the nucleus around which this service can be developed. The Blast Furnace and Raw Materials Committee has done excellent work. The need for beneficiation of iron ores is increasing and the economics of this operation are developing more and more in favor of increased activities. Ores that are slightly undergrade should be concentrated up to grade to supplant the present practice of mixing with higher-grade ores to bring up the average composition. Marginal ores that are not now being mined, or that are being mined and piled for future use, should be concentrated. The development of the use of sinter in the blast furnace, because of the elimination of fines, the advantage of better sizing of the charge, the resulting reduction of coke consumption, and increased output of pig iron per furnace, will make concentration and sintering become practical ahead of its natural time.

Jan 1, 1936

By Jan Knobloch

Inter Stand Cooling (ISC) can increase productivity of a HSM and improve final mechanical properties of the strip. Constant Target Exit Temperature can be ensured for the whole strip length eliminating skid marks and other temperature oscillations of the transfer bar. The paper deals with advanced control module of ISC. Essential mathematical models of the control system is introduced and basic functionality is explained. Temperature model is based on FEM. Mechanical and thermal properties of the strip are calculated from chemical composition using neural network. Further on an experimental possibilities for investigation and design of ISC cooling headers will be shown. In conclusion practical experience with ISC on various HSM will be discussed.

Jul 30, 2018

By Lloyd Buckingham

"The operating cost of a gold mine employing granular activated carbon to recover gold can be greatly affected by the condition of in-circuit carbon and its attrition losses. To accurately identify and quantify carbon losses requires careful study. Carbon attrition in the mill can be attributed mainly to physical or mechanical breakage due to the transfer of carbon in the circuit and to carbon oxidation and thermal fracture occurring in the carbon reactivation kiln. Of the equipment involved in carbon transfer, the water powered eductors are the major cause of abrasion and should be replaced with pumps or alternate methods that can serve the purpose. This paper also reviews the impact of carbon stripping and washing on overall operations.IntroductionHolt-McDermott Mine operates a 1360 tonnes per day Carbon-in-Leach (CIL) mill to recover gold. The relatively high carbon consumption and high remaining gold values on carbon after stripping were viewed as a challenging project for research. Extensive metallurgical testwork was initiated to reduce these values. Figure 1 below indicates the carbon flowchart prior to any significant changes in the carbon handling procedures.Carbon consumption after commissioning which was as high as 10""/o of carbon eluted, has been brought down to less than 5%. Changes that brought about this 50% reduction in carbon consumption are:1 ) Improvements in kiln operation2) Elimination or replacement of eductors3) Reduction in tonnes of carbon eluted"

Jan 1, 1994

By C. T. Wallace

Evans Industries, Inc., a management coal consultant and company was assigned to evaluate National Steel Company's coal properties in Knott and Floyd Counties, Kentucky. The results of evaluation showed large reserves of good quality, high volatile metallurgical coal contained in the Elkhorn coal beds and resulted in the formation of Beaver Creek Consolidated Coal Company. Based on results of the exploration and feasibility work, the decision was to install a coal nine, preparation plant and related facilities having a production capacity of one' and three quarter million tons per year with Evans Industries acting as Beaver Creek's management company. The recoverable tonnage assigned to the Stinson Mine is approximately forty-five million tons. This paper discusses the general arrangement of storage, conveying, loading, refuse disposal facilities and the flow sheet of the preparation plant developed by engineers of Heyl & Patterson, Inc., and Evans Industries, Inc., with emphasis on practical flexibility, sulfur reduction in all circuits, and high product yield with the minimum amount of selective mining, Three and one-half miles of railroad have been built by the Chesepeake & Ohio Railroad to service this mine.

Jan 1, 1970

By D White, L. Lorenzen

Sampling and metallurgical testwork during various phases of engineering studies is of paramount importance for a robust processing plant design. When developing a process flowsheet, risks in achieving desirable financial outcomes are minimised by ensuring that appropriate sampling and adequate metallurgical testwork support the engineering and cost estimation at each phase of project development. The quality and type of samples used for metallurgical testwork are just as important as the metallurgical testwork itself. The key characteristic required of any sample is that it represents some defined portion of a mineral deposit. Representivity should consider the spatial orientation, lithology, alteration, degree of oxidation, mineralogy, and competency of the ore such as hardness and abrasiveness. Statistically representative sampling procedures and an appropriate metallurgical testwork program should be designed to bring metallurgical understanding up to feasibility study standard and to give a basis for process plant design. The authors have observed that the quality of sampling and quantity of metallurgical testwork carried out during the various phases of engineering studies are often insufficient to truly support a robust plant design. Some designs are based on benchmarks of apparently similar ore bodies or rely on buoyant metal prices supporting cash flows until rectifications can be implemented. The paper will discuss important aspects of sampling and testwork required for engineering studies in designing process plants. Keywords: Sampling, metallurgical testwork, studies, design

Jan 1, 2020

By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the laws of Nicaragua has been prepared from the best available information in Washington , but is released subject to correction and amplification , if necessary, by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State .

Jul 1, 1930

By Qiang Zhong, Qian Li, Yongbin Yang, Tao Jiang

Thermogravimetric analysis (TGA) has been used to research the pyrolysis and combustion processes of coal used in rotary kiln of iron ore oxide pellet. Furthermore, the effects of air flow and oxygen concentration on the combustion behavior of coal were examined with TGA. The results showed that two individual stages can be distinguished for the pyrolysis of coal, the water evaporation stage and the de-volatilization stage. And the information on ignition and burnout characteristics can be obtained from the combustion process analyzed by TGA. Large air flow almost has no effect to the combustion process except that it enhances combustion intensity. However, the combustion process is further accelerated under oxygen-enriched conditions. With all experimental results, it could provide an attractive approach of analyzing coal for the rotary kiln process.

Jan 1, 2016

Bernard MacDonald, Guanajuato, Mexico (communication to the Secretary*):—Mr. Iceyes's paper is very interesting to me because of my personal experience with the development of the ore-deposits of Lake Valley.

Jan 1, 1909