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By Song Jiang, Xianzhi Tan, Minjie Lian

"The ground water heat pump system lades underground hot water which can be heated or cooled by heat exchanger in water source heat pump air conditioner. This system replaces the model of heating of air-conditioning by refrigerator and boiler. In this paper, the formation conditions of hot water energy in Shan Dong are analyzed in order to achieve the purpose of energy conservation and emissions reduction by taking full advantage of water resources such as water pouring and return water of beatification during the productive process of underground metal mine. In order to analyze the issue better, the paper points out some ways and methods for geothermal water often used in underground metal mine. This paper also presents the advantages of the technology of water source heat pump that is applied into underground metal mine. Here is a case study of comprehensive utilization of water source in a certain underground metal mine in Ji Ning. This mine, according to its own actual situation, designs heat pump heat exchange system which is used for indoor heating of buildings and bath for staff. It turns out that the system can save 23% water per year, cut down 3.303 million KW electric energy, and reduce 4160t emission of carbon dioxide. It is concluded that the technology of water source heat pump has broad application prospects in underground metal mine. Therefore, the results show that it is an ideal way to change the present structure of cooling and heating source in metal mine.Introduction In recent years, overuse of fossil fuels has posed a grave threat onto the environment, which makes renewable energy a more important status in energy structure. Development and utilization of renewable energy has become an important direction. Water source heat pump technology is to use solar energy stored in water as cold/heat source to convert energy. Currently, this technology has been widely used in some advanced countries. However, due to facers of implementation technology and component costs, there is still a gap in water source heat pump technology between China and these advanced countries. According to (Blum et al 2011) that after in-depth study, water source heat pump technology has developed rapidly in China recently, and the gap is gradually reduced. Groundwater source heat pump system as a kind of high efficiency, energy-saving and environmentally friendly technology in recent years, more and more get the people's attention. At the same time, its practical application has also been rapid development. Based on (Ni et al 2015) that According to the relevant departments of the prediction, the technology will become the 21st century the most efficient heating and cooling technology."

Jan 1, 2017

By V. H. Wilhelm

Drilling activity in California during 1939 decreased approximately 15 per cent from that of the previous year. New reserve discoveries were the lowest in many years, but extensions, development of deeper sands, and reappraisals, indicated enough new potential to more than equal 1939 withdrawals of about 223,644,000 barrels. On June 1 a new uniform method of allocation was adopted, which had the immediate effect of reducing production, so that approximately 6,000,000 bbl. of crude were withdrawn from storage during the year. Market demand averaged 628,845 bbl. per day as compared with a daily production of 612,945 barrels. The rate of drilling was slow during the first five months because of the unfavorable storage situation. Subsequent to the adoption of the new uniform method of allocation on June 1, drilling was speeded up and continued at a rapid rate throughout the remainder of the year. As a result of prospecting, four new fields were discovered and seven fields were measurably extended. All of the new discoveries were made in the San Joaquin Valley. Statistics of production and development arc given in Fig. 1 and Tables 1 to 3. New Discoveries Coalinga-Northeast.—The Amerada Petroleum Corporation discovered a second Eocene shore-line field north of the Coalinga Nose when it brought in well S.P.L. 7-17 in sec. 17-19-16, flowing 4230 bbl. of 32.4" gravity oil and 14,200,000 cu. ft. of gas at a depth of 8237 ft., from the "Gatchell" sand of Eocene age. This field, 2 miles north of the Coalinga Nose field, is considered to be a separate structure because it has a gas cap and a lower water table. The structure is a broad, gentle anticlinal nose probably separated from the southerly Coalinga Nose field by a shallow syncline. Production is sealed updip by the pinching out of oil sands. The average sand thickness is approximately 200 ft., the top 75 ft. containing mainly gas. The sand has an average permeability of 1000 millidarcys and an average porosity of 25 per cent. The productivc area of the field is estimated to be between 1200 and 1500 acres.

Jan 1, 1940

By J. F. McLaughlin

The installation of the Chance flotation system for the preparation of anthracite demonstrated the need for some means by which the specific gravity of the fluid mass in the separating cone could be determined with a fair degree of accuracy. The means used (with the original cones) was a set of wooden balls attached to ropes or chains, each with a different specific gravity. In the Northern Anthracite field, where the cones are generally operated with the specific gravity at 1.65, these gravity balls are provided with a range of 1.6, 1.65, 1.7 and 1.75. The operator of the cone from time to time would place one or more of these balls in the cone and estimate its specific gravity by the action of the balls. The margin of error with this system was very great, because there was the possibility that the test ball might be held in suspension and carried around by material floating beneath the surface of the cone in what is known as "island " formation—a formation resulting from a low sand line in the separating cone. The inaccuracy of this system of determination of specific gravity was indicated also by periodic tests of the final refuse bank, which showed excessive losses of coal to the refuse. Further evidence of the unsatisfactory operation of the cone was the uneven appearance of the market product, which caused spasmodic condemnation. Maintenance of Even Preparation With the critical market condition of today, it is essential that the preparation units operate consistently to maintain an even preparation. If a plant wishes to maintain a 1.65 specific gravity preparation, which means that all material of a specific gravity greater than 1.65 is classed as "reject," if the specific gravity of the fluid mass runs to 1.70, the market product will not be satisfactory; or if the specific gravity of the fluid mass is 1.60, the market product will be entirely satisfactory but the losses at the slate ends will be excessive. The desired specific gravity of the fluid mass in the Chance cone is maintained by agitating the sand within the separating cone by means

Jan 1, 1931

By Willard R. Jillson

Within the last ten years Kentucky has become celebrated for its low-sulfur bituminous coals. Prior to this time, many investigators had discnvered the abundance of this coal but the fact was unknown to the general public until the last extension of Kentucky's mountain railroads' was completed. The coals of. Kentucky are, broadly, separated into two geographic units—the eastern and the western coal fields. On a basis of their sulfur content these coal fields fall into three units, which are indicated on the accompanying map, by numbers, 1, 2, and 3. The area marked 1, the very southeastern part of the state, shows the lowest sulfur, all coals being averaged. In this field the maximum is 1.04 per cent. and the minimum as low as 0.68 per cent.—both averages and not individual analyses, which would of course show much greater variation. Included in this group are the following counties: Lawrence, 0.87 per cent.; Martin, 0.75 per cent.; Johnson, 0.73 per cent.; Magoffin, 0.87 per cent.; Floyd, 0.88 per cent.; Pike, 0.68 per cent.; Knott, 1.04 per cent.; Perry, 0.77 per cent.; Letcher, 0.80 per cent.; Leslie, 0.70 per cent.; Harlan, 0.79 per cent.; Knox, 0.86 per cent.; and Bell, 0.92 per cent. The total average sulfur content for these thirteen counties is 0.82 per cent. Bordering the restricted low-sulfur field of eastern Kentucky is the No. 2 belt (slightly darker), 'which is commonly known as the western border of the eastern coal field. Here the maximum sulfur is 2.91 per cent. and the minimum 1.05 per cent. Again these are averages and not individual analyses. The counties in this group are: Greenup, 2.60 per • cent.; Boyd, 1.67 per cent.; Carter, 1.07 per cent.; Morgan, 1.40 per cent.; Wolfe, 1.83 per cent.; Lee, 2.93 per cent.; Breathitt, 1.85 per cent.; Owsley, 1.09 per cent.; Jackson, 1.06 per cent.; Rockcastle, 2.30 per cent.; Clay, 1.09 per cent.; Laurel, 1.08 per cent.; Pulaski, 2.24 per cent.; Whitley, 1.05 per cent.; McCreary, 1.50 per cent.; and Wayne. The sulfur percentage average for this area including fifteen important counties is 1.65 per cent. In the western Kentucky field, the great increase in the percentage of sulfur is at once apparent. Ohio County with 3.78 per cent. is the highest and Hancock with 2.87 per cent. is the lowest. The percentages by counties is as follows: Hancock, 2.87 per cent.; Henderson, 3.22 per cent.; McLean, 3.27 per cent.; Muhlenberg, 3.31 per cent.; Hopkins,

Jan 1, 1920

By W. H. Kantner

IN this paper, no attempt will be made to theorize on subsidence. Only known data and actual facts will be given, with a few exceptions noted where other factors and outside influences tend to change sub-sidence directly resulting from porphyry caving. The area under observation is known as the Southeast Extension of the East orebody. The orebody is irregular in outline and dips to the south and the east, extending in depth from about 425 ft. below the sur-face to 1050 ft. below the surface. In the upper horizon, the orebody is about 400 ft. long and 150 ft. wide. At 720 ft. below the surface, the ore outline is approximately 450 by 170 ft.; 70 ft. below this, it is 500 by 110 ft., with an extension at the north end to the east 270 by 120 ft. From this elevation to about 900 ft. below the surface, the ore spreads out to the east and south, being about 700 by 500 ft. between these vertical limits. Below this it pinches out and at 1060 ft. below the surface is only 100 by 100 ft. The nearest point of the orebody-which is on the northwest side-is 600 ft. southeast of the Sacramento shaft. The country rock is all porphyry. Fig. 1 is a vertical east-west section showing orebody and original surface. The surface over the orebody was fairly regular and in this area and adjacent to it were portions of the surface plant, roads, and the main plant railroad to the concentrator. Fig. 2 is a map of the surface over the porphyry area. Caving operations started in April, 1925, at the approximate top of the orebody. The first lift was on the 600-ft. level; the ore was extracted by means of the Morenci timbered slide method and was from 425 to 455 ft. below the surface over an area of about 22,000 sq. ft. This lift was finished in May, 1926. The second lift, on the 650-ft. level, was already in production by May, 1926, so extraction of ore was continuous. This lift was 48 ft. high and covered an area of about 30,000 sq. ft. The ore from this lift was extracted by means of a modified Morenci timbered slide method. This lift was finished in March, 1927. The direction

Jan 1, 1934

By K. R. Evans

The deformation mechanisms occurring in polycrys-talline, commercially pure titanium and a Ti-8 pct A1 alloy have been investigated and compared to earlier results by Levine on high-purity titanium single crystals and by Conrad on commercially pure titanium. In accord with Levine, two consecutive deformation mechanisms are observed to exist below 500°K with the transition temperature between mechanisms, Tc, strongly dependent upon interstitial composition. T, is found to be 210°. 375° -430°, and 450°K for alloys A large number of investigations have been conducted to determine the rate-controlling mechanisms of plastic deformation occurring in fcc and bcc metals. Very few investigations of a similar nature have been conducted for hexagonal metals. In fact, until very recently, magnesium is the only hexagonal metal which has been systematically investigated for determination of the rate-controlling deformation mechanisms.1"3 From these investigations, it was concluded that basal slip below 420°K occurs by the intersection of forest dislocations,1'3 while for prismatic slip the Peierls mechanism is rate-controlling at low temperatures with interstitial compositions of 0.024, 0.42, 0.61, and 1.13 at. pct expressed in terns of oxygen equivalents. The low-temperature mechanism is found to be an impurity obstacle mechanism in contrast to Levine's earlier conclusion of the Peierls barrier. Measurement of the activation parameters for deformation and estimation of the force-distance profile of the obstacles show their retarding force to be effective over longer distances from the obstacle as the interstitial composition increases. and thermally activated cross slip at higher temperatures. 2 The potential technological importance of titanium alloys has prompted recent studies of the deformation and fracture characteristics of titanium and its alloys. 4-8 Levine' systematically investigated the low-temperature deformation behavior of high purity titanium single crystals oriented for either basal or prismatic slip. It was concluded that the Peierls mechanism was rate-controlling at temperatures below 210°K, while above this temperature an undefined mechanism was rate-controlling. Conrad 7,8 concluded from an analysis of the composition dependence of the critical shear stress at 0°K and measurement of the activation parameters that the low-temperature deformation of titanium is controlled by an impurity

Jan 1, 1969

By George G. Thomas

IN April 1949, Newfoundland became the tenth province of Canada. It had been a Dominion of the British Commonwealth, though actual Dominion status had been suspended for some fifteen years. During that fifteen-year period the Government had been by commission. Throughout the regime of the Commission Government, a limited program of investigation of the mineral resources of the country was in progress. It was during this period that the investigation of the iron resources of Labrador by the predecessors of the Iron Ore Company of Canada began. Since Confederation there has been a marked change in the attitude of mining capital to the new province and a notable acceleration in the tempo of prospecting and exploration. There is no private Newfoundland capital available for mineral exploration. In the past, as now, capital must be attracted to the province. Prior to Confederation, Canadian capital had to cross the barriers of customs and immigration. American capital hazily regarded Newfoundland as part of Canada, with one notable exception, the American Smelting and Refining Company at Buchans. Buchans The most significant mining development in Newfoundland today is the property of the Buchans Mining Co. Ltd., a subsidiary of the American Smelting and Refining Co., located at the town of Buchans. Their milling operation produces lead, zinc, and copper concentrates by selective flotation, and also produces a small amount of gravity concentrate. Presently the mill treats, about 320,000 tons of ore per year. Production started in 1928 at 500 tons per day and has been raised over the years to the present figure of 1200 tons per day. Conventional prospecting methods uncovered the original deposit. It was first examined as a possible source of sulphur from pyrite. Geophysical prospecting and diamond drilling resulted in discovery of enough additional ore to warrant a large scale operation. Mining is by open cut methods. In addition conventional underground cut and fill stoping and square set stoping methods are employed. Between 850 and 900 men are employed at Buchans. Concentrates are shipped by rail to Botwood and leave the country through the port. Buchans Mining is currently investigating a Crown concession covering an area of approximately 6250 square miles, adjacent to the area of present operations. Aerial photographs have been made of the area, and geologic parties, supplied by plane, are in the field during the summer months. The concession lies south of the Falconbridge concession. The geology of the Buchans area can be divided into three groups. The first category is the oldest and called the Buchans Series. It consists of volcanic lavas, breecias and tuffs and underlies most of the Red Indian Lake Basin. The second is a group of igneous rocks such as granite and quartz porphyry intrusive in the volcanics. It makes for rough country north and west of Buchans. The third group consists of sills and dykes penetrating the lavas near

Jan 1, 1952

By James Norman, O. C. Ralston, John Dasher

Most mineral products are used in the finely divided state, but some are sold in larger sizes. Coal, gravel, metallurgical fluorspar, phosphate rock, hematite, chro-mite, and other products are sold in sizes coarser than can be treated by many mineral-dressing methods. Gravity separation of coarser sizes by log washing and jigging is probably as ancient as any process now in use. The performance of jigs on a feed with sufficient difference in density of the minerals is excellent, but many families of minerals are too similar in density to be separated effectively by this method. The use of heavy suspensions of fine solids to separate coarse coal from bone and slate has been in use for some years. This separation by sink-and-float was limited until recently to light minerals. Development of galena and ferrosilicon as suspension media, by Minerals Beneficia-tion, Inc., at Mascot, Tenn., Pitcher, Okla., and Crosby, Minn., under patents granted during and since 1938, has permitted excellent results to be obtained on minerals of very similar densities up to 3.3. This process has been put In the hands of American Cyanamid Co. for exploitation, and further research now in progress may increase the density of suspension obtainable so that separations at a density of 4.0 may be practicable before this is published. The Huntington-Heberlein dense-medium process, developed in England, is also being commercialized in the United States by Sink and Float Corporation. Du Pont has developed a sink-and-float separation using halogenated hydrocarbons as parting liquids; at this writing, the method is used commercially only on coal but has been successful in the pilot plant on many other minerals using tetrabrom-ethane at densities up to 2.95. While these processes were being developed to extend the range of separation by difference in density to the coarser sizes, the Bureau of Mines was engaged in developing a process that will extend the range of separation by difference in wettability up to 2-in. size. War work has pushed aside its further development indefinitely. The results are published here with the hope that some use may be suggested that will justify post-war development, and so that readers that may be able to make immediate use of the scheme may have the information. Earlier Work It has been known since the time of Herodotus (B.C. 484(?)-425) that water-repellent particles will adhere to sticky surfaces. That early historian reports the recovery of gold from the mud of a lake

Jan 1, 1943

By E. C. Potter

It is not the purpose of this paper to enter into the minutiae of a subject so vast, upon which volumes have already been written and volumes more might still be written, but simply to pass in review the characteristic features of that practice, which, dating from the blowing-in of the Edgar Thomson "A" furnace in 1879 and continuing down to the present day, has given to American blast-furnace operations a new significance. The blowing-in of " A" furnace marked the beginning of a new era in the science of iron-smelting if, indeed, it was not the very birth of science as applied to this industry in the United States. American blast-furnace practice in its generic sense and world-wide significance dates from that day, and really all that is valuable, all that is remarkable or worthy of discussion, is embraced in the experiences and achievements of the past fifteen years. Back of that we find only the dead level of mediocrity, or worse, a dispoition to " let well enough alone;" a general, almost universal, employment of " rule of thumb " methods. The application of scientific principles and methods was rare and, indeed, previous to the introduction of the Bessemer process in the early seventies, science had no place in controlling the operations of the American blast-furnace. The old practice consisted mainly in dumping raw materials in at the top of the furnace and tapping out iron and slag at the bottom, for the successful consummation of which the furnace-manager directed his best energies toward keeping the furnace as free as possible from "gobbing" with, alas ! but indifferent success. The burdening of the furnace was based largely on Mark Twain's receipt for " Johnny-cake," altered to suit the circumstances, viz.: a lot of ore, a lot of fuel and about a quarter of a lot of flux. The possible capacities of furnace-plants were not nearly realized. Enormous wastes were permitted, unheeded because not understood. In the use of fuel quantum suff. was always the rule. Increase of product was not thought of because it was not deemed wise or safe to attempt

Jan 1, 1894

By Donald E. Cummings

Certain dusts are dangerous when inhaled, but most hazardous of all dusts are quartz or other forms of pure crystalline silica. The inhalation of dusts containing silica in combination with other elements gives rise to changes in the lung which differ from those produced by pure silica. As a generality, silicates are less dangerous than pure crystalline silica and vary greatly among themselves in harmfulness. Repeated analyses have shown that approximately 70 per cent of the total number of particles involved in any dust-producing operation are below 1 to 2 microns in diameter. (A micron is approximately 1/25,000 in.) Similar studies of dusts recovered from silicotic lungs post mortem have demonstrated essentially the same size frequency distribution, except that the upper limit of size retained in the air sacs is approximately 10 microns. Experiments carried on by Gardner and the author have further demonstrated that greater changes were produced by a fixed weight of very fine quartz particles (2 to 3 microns and smaller) than by the same weight of slightly larger particles (8 to 10 microns). Any attempt to control a dust hazard should therefore be directed toward the removal from the working atmosphere of particles less than 10 microns in size, and particularly those below 3 microns. All industrial hygienists agree on this matter, but there remains considerable dispute as to the lower limit of particle size capable of causing injury. It has been generally conceded, however, that particles of harmful dusts smaller than 1/4 to 1/2, micron are not essentially concerned in the development of pulmonary fibrosis. This opinion is partly substantiated by the existence of large numbers of these small particles in practically all atmospheres that are not associated with any known hazard. Such particles are so small that they have very little mass, fail to settle even in quiet air, and probably are not easily retained in the lung. Until further research proves that they are involved in the dangers provoked by the inhalation of certain dusts, engineers will generally agree that it is better to disregard them.

Jan 1, 1937

By Robert MacPhail, Louis Racine, Bret G. Cousins

"Sodium Isopropyl Xanthate is employed in a wide variety of sulphide flotation procedures due to the specificity over other xanthates and the cost savings over other sulphide collectors such as thionocarbamates, xanthogen formates and dithiophosphates. An investigation carried out by Tennants Research Technology Applications (TRTA), has produced a chemically enhanced SIPX that has shown all the advantages of normal SIPX along with improved recoveries.Currently, FLEX 31 is manufactured at the Prospec Chemicals xanthate plant in Fort Saskatchewan, Alberta, Canada. Prospec, founded in 1983, produces approximately 4500 tonnes of xanthates per year and is presently undergoing expansion to produce approximately 6000 tonnes. The proprietary process for FLEX 31 is a new addition to plant operations that include the production of xanthates, thionocarbamates and xanthogen formates.This paper will cover the testwork on the zinc flotation circuit at the Louvicourt Mine in Val d'Or, Quebec. This testwork indicated that FLEX 31 could replace SIPX due to the ability of the FLEX to improve zinc flotation kinetics without adversely affecting final concentrate grade. FLEX has presently replaced SIPX in the zinc circuit at Louvicourt.BackgroundThe Louvicourt deposit is hosted by greenschist facies Archean volcanic rocks located in the southeast portion of the Abitibi Greenstone Belt. In the Val d'Or area, the volcanic rocks form an east-west striking, steeply dipping and south-facing sequence composed of thick mafic and ultramafic flows of the Lower Malartic Group.The joint venture has three partners-Aur Louvicourt Inc. (30%), Novicourt Inc. (45%) and Teck Corp (25%). Aur Resources holds 30% interest through Aur Louvicourt, a wholly owned subsidiary and is the operator of the project. Novicourt Inc. is 60.9% held by Noranda.Approximately 75% to 85% of Louvicourt's revenue comes from the sale of copper; 10% from gold (in the copper concentrate); 7% from zinc and 3% from silver (also in the copper concentrate) The copper at Louvicourt is fairly ""fast floating"". About 60% of the copper in the ore can be concentrated in the first flotation cells with feed grades of approximately 4% copper.The initial testwork and pilot trials had indicated that it would be difficult to achieve zinc grades over 52% and recoveries would have to be kept at a level amenable to salable concentrate grades. The actual mill results, with a fine regrind, achieved zinc grades of 55% to 56% at about 75% recovery."

Jan 1, 1996

By Luis Elek

DEVELOPMENT of the cement industry in Mexico began some 40 years ago. It has gradually reached great importance in the economic life of the country and has contributed greatly to the technical and economical advances which have been so noteworthy, particularly during the last 15 years. From a modest start, the industry now comprises 18 cement-producing plants having a potential annual capacity of approximately 14 million bbl. About half the plants were built and equipped with second-hand machinery during the last world war when no new machinery could be procured. They will hardly attain full production before being modernized and reconditioned, a job now under way in several of the plants. At present, the yearly consumption is only about 8 to 9 million bbl but is steadily increasing. This is only a fraction of the cement consumed in the U.S.A., which is about 250 million bbl per year, although on the basis of consumption per capita per year, the figure is 1/3 bbl for Mexico and 1 2/3 bbl for the U.S.A. Cement consumption in Mexico is well above the average of all other Latin American countries, with the exception of the Argentine, and considering the potentialities and undeveloped riches of Mexico, the road construction and irrigation works, it is fair to assume that the Mexican cement industry will still prosper and expand in spite of temporary setbacks in the future caused by-local events of economic or political nature. Portland cement is manufactured by burning a mixture of raw materials, one of which is mainly composed of calcium carbonates and the other of aluminum silicates. The most typical materials answering this description are limestone and clay, both of which occur in Mexico in many varieties. To be usable for cement manufacture limestone should contain at least 77 to 80 pct calcium carbonate. Lower grade limestone can be used for cement manufacture only if the lime content is increased by the beneficiation process, which has not yet been adopted by the Mexican cement industry. Most of the limestone used by Mexican cement plants has a calcium carbonate content of 90 to 95 pct and therefore requires addition of one or several correction materials. A typical composition of raw mix for cement manufacture is 85 pct limestone and 15 pct shale, clay or volcanic materials. Occasionally it is necessary to add a smaller amount of sand or other siliceous material to increase the silica ratio in the raw mix. Likewise, it is sometimes necessary to add 1 or 2 pct iron ore to facilitate fusion in the kiln and to obtain proper relation between alumina and iron oxide. After calcining and

Jan 1, 1952

By W. I. Duvall, D. E. Stephenson. Discussion by R. G. K. Morrison

R.G.K. Morrison (Chairman, Dept. of Mining Engineering and Applied Geophysics, McGill University, Montreal, Que. Canada) - The authors have introduced a subject, the intensive study of which has awaited scientific developments. These are now such as to justify a thorough review of our thinking on the causes and control of rockbursts. The formulae developed in the paper, the comparison between rockbursts and earthquakes in figure 1 and the energy data relating to explosives serve as an effective foundation. In the paper this writer is quoted as suggesting that energy of the order of 10 x 10 11 ft. lb. may have been released in some of the heaviest rockbursts in the Kolar Gold Field. He now hastens to add that such an estimate has no scientific validity. It arises only from a casual comparison of surface and underground effects of the medium heavy bursts, referred to in the paper and estimated by Jones at 3.0 x 1010 ft.lbs., with those of obviously greater magnitude. In any case, we have the estimate by Jones above, that by a team of seismologists 1 on the Witwatersrand of 10 x 1010 ft.lbs., that by Coates of 3.8 x 10" ft.lbs., also referred to in the paper, that by Blan-chard2 for the catastrophic rockburst at Springhill, N.S., of only 7.4 X 107 ft. lbs., and finally the range covered by Cook, referred to in the paper. It is probable also that data for the heavy rockburst at Merkers3 in the WERRA potash area of Germany are available as it was recorded on seismographs from Moscow to Spain. It is the writer's impression that some standardization is present in the estimates above for 10 x 10 10, 3.8 x 1010 and 7.4 x 107 ft.lbs., respectively. The latter, for Springhill, represents a relatively low order of magnitude. It is obvious that any energy estimate must be related to the local geometry of openings at the time of the event. It is also obvious that any explanation of the causes of rockburst must be capable of providing a wide range of energy. However, we must remember that the energy release is an effect indicating magnitude. The cause lies with the mechanism initiating the primary failure, generating the seismic activity, to which much of the damage is probably due.

Jan 1, 1967

By J Ding, H J Peng, S B. Zhu, L Hou, J R. Zhang, S Y. Wu

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Numerous Fe-Cu-Au-rare earth element (REE) deposits have been identified within the Palaeoproterozoic Dongchuan Group of the Kangdian region of SW China. Geochronologic and geochemical data of the dolerite dykes and other volcanic rocks reveal extensional activity occurred about 1.7 Ga called ‘Kunyang Rifting’. The Kangdian region underwent variable degrees of extension, meaning that breakup in the central part of this region occurred earlier than in the north. Research on microphysiography, isotopic geochemistry and inclusions of the Yinachang typical Fe-Cu-Au-REE deposits suggest that the dominant mineralisation fluid is high-temperature, high-salinity magma fluid, containing alkalic components, volatile phase and Cu-Au. Metasomatism and mixing between this magmatic fluid and carbonaceous wall rock and meteoric water caused the precipitation of Fe, REEs and Cu-Au. A chalcopyrite Re-Os age from the Yinachang deposit obtained during this study is some 50–100 million years younger than the timing of emplacement of the deeply sourced Haizi and Dongchuan dolerites. The Yinachang deposit is a typical iron oxide-copper-gold (IOCG)-type deposit, and the presence of this and other deposits in the Kangdian region indicates that the region hosts an intraplate extension-related IOCG system within the western edge of the Yangtze Block, China.CITATION:Hou, L, Ding, J, Zhang, J R, Zhu, S B, Wu, S Y and Peng, H J, 2015. Proterozoic iron oxide-copper-gold mineralisation in the Kangdian Region, south-west Yangtze block, China – a case study on the Yinachang Fe-Cu-Au-rare earth element deposit , in Proceedings PACRIM 2015 Congress, pp 255–264 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Magnus Evertsson, Haijie Li, Erik Hulthen, Mats Lindqvist

"The static and dynamic models for autogenous (AG) and semi-autogenous (SAG) mills have been studied for decades. Though the effects of mixing soft and hard ores in a mill and their interactions are not widely investigated. To develop a general numerical model for AG/SAG mills, a dynamic model has been introduced, and its capability to simulate multi component ore breakage has been examined and compared with previous publications. The simulation results show that the dynamic model can cover a range of milling conditions and is able to simulate complex scenarios with soft and hard ores. The dynamic model discussed here could provide substantial potential for the controlling and optimization of the comminution circuits. INTRODUCTION In the last decades, efforts have been devoted to studying the comminution circuit due to their high energy consumption. The energy directly spent in minerals comminution was about 2% globally in the year 2000 (Maurice et al, 2003). As one important part of the comminution process, AG/SAG mills are widely used for primary grinding in minerals processing. AG/SAG mill models include static and dynamic models (Kojovic et al, 2012; Yu et al, 2014; Yu et al, 2017; Liu and Spencer, 2004; Salazar et al, 2009). Many static models have been well validated over the past decades, but they are all based on steady state assumptions. Even though plants experience a steady-state condition under certain circumstances, it can be inaccurate to simulate the system by static models under all circumstances (Asbjörnsson et al, 2013). The advantages of a dynamic model are apparent that it provides more information and insights both inside the mill and through interactions with other machines in terms of pebble crushers, conveyor belts, screens and so on. In many mines, the multi-component grinding is inevitable, and the ratio of hard and soft components in the mill strongly affects mills operation and performance. Bueno (Bueno et al, 2010; Bueno et al, 2013) studied the effects of blending hard and soft ores in AG/SAG mills and used them to update the JKSimMet toolkit which was a steady state plant simulation software. However, due to the complexity of the particle interactions such as multi-component breakage function, appearance function, in mill transportation, there has been no dynamic AG/SAG mill models developed yet for simulating multi-component."

Jan 1, 2018

By S. H. Shahcheraghi

The four operational parameters including collector dosage, frother dosage, conditioning time and pH, are the most important parameters effective on the flotation kinetic. The present study has been done at the Miduk Copper Complex in the province of Kerman. The effect of operational parameters on the flotation kinetic of copper minerals were studied and analyzed, so the optimum conditions for flotation kinetic of copper sulfide minerals were obtained. Under the obtained optimum operational conditions, the recovery of copper sulfide flotation at the 95% confidence level was estimated to be between 92.76% and 95.48% and the copper sulfide flotation kinetic constant was estimated to be between 1.40 and 1.45 min-1. Results showed that the consumption of the X231 collector (O-isopropyl-N-ethylthionocarbamate) and the A65 frother (Polypropylene glycol) could decrease up to 35% and 50% respectively while the copper sulfide recovery increases about 1 up to 2% at the laboratory scale. Keywords: flotation kinetics, sulfide copper, optimization, the Miduk Copper Complex, response surface method

Sep 1, 2012

By Robert P. Harrison, Marie-Christine Patoinel, Kristian E. Waters

This paper describes a collaboration between McGill University and Hatch Ltd. to expose undergraduate students to real-world industrial projects. As part of the final-year design course, the students receive a detailed lecture on Scale-Up of New Technologies', including seven case studies drawn from over fifty years of full-scale industrial projects. The students are taught the basic concepts of scale-up, including the limits of pure theory and the need for empiricism. Insights from real scale-up failures and successes are fictionalized as Projects A, B, C, etc. The students are then asked to identify the guiding principles that can be distilled from these case studies.

Jan 1, 2011

By A. Alfantazi, M. Mahon

The current efficiency in zinc electrowinning is a key indicator of the performance in a cell house. This is typically measured by comparing the weight of the cathode to the electric current applied over the deposition period. This calculation can be cumbersome because the deposition history of each pulled set of cathodes will be unique. It will depend on the applied current and electrolyte conditions from onset of deposition until the cathode is removed and stripped. Not accounting for these can introduce errors to the calculated current efficiency. To track this history and reconcile the current efficiency, a time based computer process simulation was made of an industrial cell house. Two months of hourly recorded measurements from the cell house were input to the simulation, including current to the cell houses, concentrations, flow rate, and temperature of the purified leach solution. The simulation’s predictions of the concentration of zinc in the circulated, spent, and returned electrolyte all showed good agreement with the industrial data over the two months giving a validated zinc balance. The simulation was then tuned to predict the instantaneous current efficiency for all times, as well as the expected masses for the deposits given their deposition history.

Jan 1, 2014

By G Chitombo, A Perryman, A D. Campbell, J White, B Hollis

This paper describes the development and implementation of an optimisation tool developed as part of the Mass Mining Technology (MMT) Project. The tool, known as the SLC Schedule Optimiser, is capable of optimising the schedule of development and production activity for a sublevel cave, given a fixed draw strategy, for the life of the mine.This paper starts by describing the development and production scheduling problem for a sublevel cave, the geotechnical constraint that a schedule of activities must adhere to, and outlines the pre-existing manual planning procedures used to produce schedules.Following this, the paper then outlines the optimisation tool developed, describes the changes to the planning process it has enabled and finally quantifies the improvement to operations this tool has brought using Glencore’s Ernest Henry Mining Operations as a case study.CITATION:White, J, Perryman, A, Campbell, A D, Hollis, B and Chitombo, G, 2016. Life-of-mine development and production scheduling optimisation for sublevel cave operations, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 133–138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By V Gau, L Overmeyer, M Kesting

Economically efficient mining processes can be significantly assisted by the implementation of sensor technologies for the detection of materials and boundary layers between materials inside the stratum. These sensors are meant to facilitate the machinery operator and illustrate furthermore the prerequisites in assisting tools towards fully automated mining equipment. Therefore, project æSensory Identification of Material Type and Detection of the InterfacesÆ (SIMT) aims at the integration of ground penetrating radar (GPR) and geoelectric sensor technology by endowing with them a bucket of a bucket wheel excavator. For this reason, a sensor bucket was developed and tested in the Inden Mine of RWE Power AG. The feasibility of integration and deployment of such sensor technology has been proven effective for the conditions of open cast mining. The main focus of current research lies on developing algorithms to analyse the acquired measurement data from the sensors to automatically detect layers and materials. A computer network receives the GPR and geoelectric measurement data as well as the positioning data of the sensor bucket. The positioning data mainly consists of GPS and encoder information, which is merged with the sensor data by using the UTC time stamp. With the aid of consecutive processes the relevant information will be extracted and provided to the user. The aim of SIMT is to replace material identification, traditionally carried out by the operator, by implementing a continuous operating interpretation system in mining equipment based on GPR and geoelectric sensor technology, resulting in more detailed information regarding the working face during an excavation. This detailed information provides an opportunity for efficient planning and controlling of selective mining of natural deposits, such as the process of lignite mining.

Sep 26, 2011