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By Marsh S. Watson, Robert A. Howard

The effect of depth of formation penetration by casing perforations has been studied by means of an electrolytic model. It is found that the relative productivity of perforated casing is profoundly affected by the depth to which the formation is penetrated. The first in. of penetration i: of especial importance. A scaling equation which was shown to agree with experimental results at zero penetration is used to calculate the relative productivity of a waled down casing with scaled down perforations. INTRODUCTION In an earlier piper' the authors showed that the point sink representation of casing perforations is inade- quate. It was Pointed out at that time that while the electrolytic model results were a marked improvement over point-sink calculations, they still left a great deal to be desired in that the electrolytic model represented a case not realizable in practice, namely, a clean hole through the casing but undisturbed formation on the other side of the casing. Obviously, to be effective, the perforation must penetrate a finite distance into the producing formation. It was the purpose of the present investigation to find how the relative productivity of perforated casing varies with depth of penetration. The term "depth of penetration" as used in this paper refers to the distance which the perforation penetrates the producing formation. The amount of casing and cement penetrated is not taken into account, a fact which is discussed more fully later. The "casing radius," therefore, is to be interpreted as the radius of the boundary between cement and formation wall. in cases where the casing is not in contact with the formation wall. APPARATUS The electrolytic model experimental setup was identical with that described in the previous paper' except that the platinum electrodes were now allowed to project from the lucite cylinder by varying amounts. When fewer than eight electrodes were used, the unused ones were covered with a coat of insulating material to minimize disturbances to the current flow-lines. Comparison runs made with the unused electrodes uninsulated, however, showed that the values of Q/Q0 so obtained did not vary by more than the experimental error from the values obtained with the unused electrodes insulated RESULTS The variation of relative productivity* with perforation density is shown for various penetration depths from 0 to 4.03 in. in Fig. 1. It will be seen that even one in. of penetration into the formation results in a huge increase in the relative productivity. Moreover, as-the depth of penetration increases, it becomes less and less advantageous to use large perforation densities, 80 pel. cent of open hole productivity being obtained with only three 0.5-in. diameter holes per foot when the penetration is 4.03 in.

Jan 1, 1950

PRESIDENT AND DIRECTOR CHESTER A. FULTON NEW YORK, N. Y. PAST PRESIDENTS AND DIRECTORS EUCENE MCAULIFFE OMAHA, NEBR. C. H. MATHEWSON NEW HAVEN, CONN. TREASURER AND DIRECTOR ANDREW FLETCHER NEW, YORK, N. Y.

Jan 1, 1944

By Lyall Zickrick

NUMEROUS brands of virgin pig lead are used in the manufacture of lead and lead-alloy cable sheath for commercial cables. In changing from one brand of pig lead to another a readjustment of press operating conditions is nearly always necessary. This is due largely to different flow characteristics, and some brands extrude at a much lower pressure than others; for example, copper-bearing lead requires much more pressure than a low-bismuth lead under the same operating conditions. With the modern type of lead press the extrusion practice in general differs very little. Molten lead at a temperature of 375° to 400° C. (710° to 750° F.) is cast in a water-cooled cylinder and allowed to cool or solidify into a slug for six to nine minutes. . This slug is forced into the die block and around the core tube through which the cable runs. The die block is held at an optimum temperature by means of gas flames, usually 175° to 225° C. (350° to 4.35° F.). Measurements of the tem¬perature of the cable sheath taken at the time of extrusion have covered a range of 190° to 225° C. (375° to 435° F.). According to Tammann, the rate of extrusion for a metal under constant pressure through a simple orifice is almost doubled for each 10° C. rise in temperature. Because of the irregularity of die-block construction, such a great increase is not obtained in lead-cable extrusion practice. To obtain more" definite information about the effect of small per¬centages of metals usually present as impurities in virgin pig lead, a series of compression tests were made covering several different brands of lead and various alloys. Since the usual temperature of the sheath is approxi¬mately 200.° C. as it emerges from the die block, these compression tests were all performed at 200° C. Five different brands of virgin pig lead were selected, as follows: Brand A: A desilverized western lead of very high purity. This lead contains neither copper nor bismuth. Brand B: A bismuth-free southeastern Missouri lead, usually con¬taining 0.05 to 0.08 per cent copper. Brand C: A copper-free mid-western desilverized lead of very good grade, usually containing around 0.06 to 0.10 per cent bismuth.

Jan 1, 1932

By Sushil Bhandari

A computer model is developed for the problem of dispersal of dust (suspended particulate matter) resulting from blasting operations in surface mines. Undulated surface (lower boundary) simulation was carried through sixth order polynomial by least square approximation. Segmentwise terrain simulation was linearly added to build ground feature extending either side of the blast location. Assuming the initial dust concentration in the vertical column to. be uniform and treating the finite vertical line sources as a series of point sources to height, H varying from zero to top of the dust mushroom, integration was done of the concentration effects from H = 0 toL tan[0] (L = horizontal distance of the blast location and [0] is the angle of the top of dust cloud from the point of observation). Using frame of reference moving with the mean wind, the ground level 'concentration (GLC) has been computed over the undulated terrain. Standard deviation (s) of concentration has been parameterized based on mixed layer similarity theory in convective boundary layer.

Jan 1, 2002

In submitting the accompanying sketch and description, the writer mentions that he has found this "gadget" a useful assay office adjunct.He believes that some millmen and assayers have been confronted, from time to time, with large samples of mill pulp for assay purposes and that although the commonly used method of coning and quartering dry sample is simple and effective, provided the samples are of reasonable proportion, the operator is frequently confronted with samples of pulp, sometimes up to 50 gallons. The writer stresses the advantage of being able to handle these samples. This fact inspired the design of the "gadget,"which was developed at the Kalgoorlie State Battery and has been found to give very reliable results. It has considerably eased the work of the assay office.Description. - A cone of suitable dimensions according to requirements (this one is about six gallons' capacity) is mounted on a light angle-iron frame and has a small hand-operated agitator paddle let into it far mixing purposes. The agitator and head frame are removable to facilitate cleaning. Four outlet pipes at the bottom at right angles to each other are controlled with one common plug, externally operated for discharging the pulp.Each operation of the machine delivers four equal parts; one or more of these can be used for further division as conditions require. Samples can thus be reduced to suitable assay room size in a few minutes.The dotted lines, enclosing the shaded portion, represent the four-bladed paddle.Each paddle is slotted with three parallel slots. Unshaded portions represent slots.

Jan 1, 1939

E L. DEGOLYER, our new president, though a petroleum geologist by profession, has always s been associated with mining, for soon after his birth at Greensburg, Kan., on Oct. 9, 1886, his parents moved to Joplin, and when he went, in the course of time, to the University of Oklahoma, he intended to follow his course there with another at a mining school. He became a field assistant in the U. S. Geo-logical Survey, however, while still an undergradu-ate, and after field experi- ence in Montana, Wyoming, North Dakota, Colorado and Oklahoma, he went to Mexico as geologist for the Mexican Eagle Oil Co. This was in 1909, and as a result he was unable to complete his work for his degree until 1911. In Mexico, he located the Potrero de Llaño No. 4, one of the world's largest oil wells, and also the dis- covery well in the Naran- jos pool; and the Colorado School of Mines conferred the honorary degree of : Doctor of Science on him in 1925. On his return from Mexico, he engaged in the consulting business, specializing in financial ap- praisement, the Union and Marland companies being among his clients. In 1919, he organized the Amerada Petroleum Co., with the backing of Lord Cowdray. Last year, control of the company was purchased by an American group, headed by Dillon, Read and Co. Mr. DeGolyer is n o w president of the company. He is also vice-president and general manager of the Rycade Corp, the Rycade Oil Corp., and president of the Geophysical Re-search search Corp. The l a t t e r represents the practical appli-cation of his inter-est in the use of the torsion balance in the locating of salt domes, in which he has pioneered, the Nash dome being the first oil field in America actually brought into production by these methods.

Jan 3, 1927

By Hendrix JL, Nelson JH

Three ores (sulfidic, oxidized and carbonaceous) were analyzed to determine the effects of leaching time, ore depth, and ore mineralogy on cyanide species concentration. NaCN solutions were percolated through opaque columns filled with milled ore. Column design made liquid sample collection possible from various depths at specific times. The concentrations of weak acid dissociable(WAD) and total cyanide, Fe(CN)63 , Fe(CN)64 , SCN , and Cu(CN)43 were determined for each sample. Extended percolation time led to increases in WAD cyanide concentra- tions and decreased SCN and Cu(CN)43 concentrations regardless of ore depth. WAD cyanide concentration decreased while Fe(CN)64 concentra- tion increased with ore depth. Highest concentrations of Fe(CN)64- SCN and Cu(CN)43 were found in the sulfidic ore, with expected low WAD cyanide concentrations. Lowest concentrations of Fe(CN)64 , SCN 3 and Cu(CN)4 were found in the oxidized ore. Intermediate concentra

Jan 1, 1988

By Robert Boutilier

For more information on what the social licence means, see the following: Joyce, S. and Thomson, I. 2000. Earning a social licence to operate: Social acceptability and resource development in Latin America. The Canadian Mining and Metallurgical Bulletin, 93(1037) Nelson, J. and Scoble, M. 2006. Social License to Operate: Issues of Situational Analysis and Process. Vancouver, BC: Department of Mining Engineering, University of British Colombia. Thomson, I. and Boutilier, R.G. 2010. The Social License to Operate In P.Darling, (Ed.), SME Mining Engineering Handbook: Littleton, CO: Society for Mining, Metallurgy and Exploration. Much of what has been written and said about the social license to operate focuses on what the company has to do or not do. But the social license is a two-sided relationship. We also need to look at what the community has to do, or not do, in order to be capable of issuing a social license that is meaningful.

May 1, 2010

By J. P. Ibáñez

The uptake of copper from extremely dilute aqueous solutions by alginate in the form of protonated dry alginate beads was investigated. Barium was used to cross link the alginate forming the beads. The effect of various experimental parameters such as pH and metal ions concentration on the uptake of copper were studied. The uptake was strongly dependent on the Cu-bearing solution pH up to a value of 4.5. A removal of 100% o was achieved when the initial concentration of copper was as low as 8.0 mg/L. The maximum uptake, i, e., the loading capacity, was found to be 167 mg of copper per g of beads. The mechanism governing the removal of copper was found to be ion exchange between protons of the alginate beads and cupric ions of the solution. For this ion exchange process a molar ratio, d[H+]/d[Cu2+], of 2.0 was determined. EPMA-EDX analysis of the Cu-loaded beads showed a uniform distribution of the ions throughout the structure of the alginate, regardless the solution pH. This may suggest that this sorbent material is a porous ion exchanger having high permeability and capacity. The uptake of copper and of the heavy metals cadmium and zinc by this sorbent is compared.

Jan 1, 1999

By King MN, Travis IC

PISCES - the Planning and Information System for Coal Export Services has been developed by Port Waratah Coal Services (PWCS) to ensure the efficient and economic operation of the Hunter Valley Coal Chain. PISCES is a computer based integrated information and management system to coordinate operations commencing at minesites through the coal chain to shiploading at the Port. The PISCES system comprises a central database around which a number of planning modules interact. These include interactive programs for train planning and timetabling, stockpile management, berthing analysis and a coal shippers enquiry system. PWCS has previously developed - number of computer based systems for planning, controlling and monitoring complex coal handling operations and the extension of the PISCES system to the Hunter Valley Coal Chain is another initiative to assist the Hunter Valley Coal Export Industry in looking confidently towards the Future.

Jan 1, 1987

By B. H. Bergstrom

The Gaudin-Meloy1 size distribution equation requires the evaluation of two constants, xo and r. The common log-log representation of a screen analysis as cumulative weight percentage passing versus size, readily yields the required constants as illustrated for curves A and B in Fig. 1. The 100% passing (y = 1.0) size is simply x,. If the straight portion of the curve be extrapolated to the 100% passing (y=1.0) abscissa, the intercept is the Schuhmann size modulus, k. The ratio of xo to the size modulus, k, is r as shown: The Gaudin-Meloy equation requires that the slope, a, of the size distribution approach unity in the finer sizes, as is the case for curves A and B. Often distributions are better characterized by slopes other than unity. The schuhmann2 equation is able to represent these distributions if the upper portions of the curves are ignored. Empirically, the Gaudin-Meloy equation can be modified to yield slopes other than unity by writing it as Here, a is the familiar Schuhmann slope, and xo is the 100% passing size. The value of r is still given by Eq. 2. Eq. 4 with its easily determined constants is more versatile than either the Schuhmann or the Gaudin-Meloy equations, since a wide variety of size distributions can be closely described. It is easier to fit than the Rosin-Rammler3 equation, and has the advantage that the top size, x,, is finite. REFERENCES A. M. Gaudin and T. P. Meloy: Model and a Comminution Distribution Equation for Single Fracture, AIME Transactions, 1962, Vol. 223, pp. 40 to 43. R. Schumann, Jr.: principles of comminution, I., size Distribution and Surface Calculations, AIME Technical Publication No. 1187, 1940. P. Rosin and E. Rammler: The Laws coverning the Fineness of Powdered Coal, J. Inst. Fuel, 1933. Vol. 7, p. 29.

Jan 1, 1967

By Beck RW, Booth GW

Differences in the gold contents of sub-sample duplicates, derived from a single bulk sample are a function of analytical and random error, inhomogeneity within the bulk and natural variations in the distribution of particluate gold. By minimising bulk sample inhomogeneity and determining analytical precision, the residual natural variation may be modelled statistically to give an estimate of Bold particle sizes.

Jan 1, 1989

By D Pepper

Despite the limited literature regarding the pressure filtration of mine tailings (compared to the large number of papers published each year on paste thickening of tailings) the number of mines dry stacking filtered tailings is approximately equal to the number of mines storing tailings in paste form. Main drivers for filtering tailings are: water recovery, future rehabilitation costs for tailings storage area and permitting requirements. In arid climates, the cost and scarcity of water justify the capital and operating costs associated with pressure filters. Further justification for filtered tailings is the potential for progressive reclamation of the dry stack, which can proceed earlier and faster than the reclamation of a tailings dam.Filtered tailings must be transported to the storage area by trucks or conveyors. For dry stacking, 70 - 80 per cent solids content (by mass) is typically acceptable, however the primary goal is to provide a filter cake that is consolidated and dry enough to prevent bridging and build-up on the materials handling equipment. It has been observed that high average solids contents (~70 per cent) can be achieved while the centre of the filter cakes is still wet and sticky, presenting challenges for the transportation of the solids. Appropriate controls must be in place to ensure consistently easy to handle solids are discharged from the filter.FLSmidth has installed two fine coal tailings dewatering systems in the United States. One of these systems incorporates a Deep Cone Thickener« upstream of the filter press to minimise the amount of water that must be filtered, while the other tailings filter press is fed by a high rate thickener. The operation and performance of these filters is discussed and compared to the lab testing used to size the full-scale equipment.CITATION:Pepper, D, 2012. Operation of filter presses for tailings dewatering, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 241-246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By A. E. Strakele, M. W. Springett, S. N. Watowich, W. F. Matlack, E. Yeomans, S. L. Manske, B. Yeomans

The Mesquite gold deposit is a large, low-grade "disseminated" ore body located in the Chocolate Mountains 65 km (40 miles) northeast of El Centro, CA. The deposit is tabular in geometry with a gentle southwest dip, concordant to a sequence of quartzofeldspathic to mafic gneisses. The host gneisses are amphibolite grade and intruded by synkinematic leucogranite and pegmatite. Reset potassium-argon (K-Ar) dates of 32 to 38 m.y. on mineral separates from gneiss in the ore body are suspected to reflect the age of mineralization. The hypo gene mineralization was introduced with siliceous breccias and -quartz veinlets and consisted of argentiferous native gold associated with minor pyrite and other base metal sulfides. Fluid inclusion study of gangue quartz indicates that the hydrothermal system contained a 225°C (437°F) boiling, 1 wt % NaCl equivalent solution with a small amount of CO2-A high degree of post-mineral faulting and fracture has resulted in deep oxidation and has obscured the original geometry and hypo gene mineralization of the ore body.

Jan 1, 1987

By C. A. Komar

The Bureau of Mines conducted oil-displacement tests in the laboratory with three water-in-oil and five oil-in-water emulsions that were created with ultrasonic energy at a frequency of 20 kHz and an acoustic intensity of approximately 100 watts per cm2. Emulsions of either crude oil or kerosine, brine, and 112 to 2 percent emulsifier were formed during 30 seconds of acoustic irradiation. Results indicate that ultrasonic energy induces greater and more uniform dispersion of one liquid in another in the presence of small amounts of chemi¬cal emulsifiers. When the emulsions were injected as a buffer slug before waterflooding, recovery of the oil-in-place was 8 to 22 percent greater than with conventional waterflooding in the test specimens, regardless of the con¬tinuous phase (oil or brine). The emulsions do not appear to be applicable to the Appalachian area; however, because the oilfields are too "tight," the clays in the formation remove the emulsifier from the displacing fluid, and not enough additional oil is produced, compared with recovery using conventional waterflooding, to warrant the increased operating costs.

Jan 1, 1969

By R. F. Mehl, B. Lustman

THE formation of intermediate phase layers in cementation processes has been subjected to extensive qualitative investigation though to relatively little quantitative study; this work has recently been fully summarized by F. N. Rhines.1 It is necessary here only to enumerate the general conclusions drawn concerning the kinetic laws governing the growth of intermediate layers and to state what is known concerning the structural changes accompanying the generation of phase layers. I. When the intermediate phase is protective in type-i.e., when its density is less than that of the base metal, so that a continuous coating is formed and maintained the isothermal growth of the phase follows a simple parabolic equation: X2 = kt [I] where X is the thickness of the alloy layer, k the reaction rate constant, and t the time. The applicability of this equation to diffusion processes is tested by plotting the square of the thickness versus time, or by plotting the thickness versus the square root of time; the resultant achievement of a straight line in such. a plot has been con¬sidered sufficient proof of the validity of this equation. Exceptions have been found where liquid phases are involved in the reaction, where the diffusion layer is cracked,2 and where thin semimetallic oxide and sulphide coatings are formed on metals.3 In the first two cases the thickness increases linearly with time, and in the latter it is a logarithmic function of time. 2. The rate of thickening varies with temperature according to the Arrhenius equation k = Ae-Q/RT [2] where k is the parabolic rate constant of Eq. I, or some other rate-descriptive function, A is the action constant, e the base of natural logarithms, Q the heat of activation, R the gas constant, and T absolute temperature. This equation has been found to be generally valid except when transformations occur during reaction in either the base metal or in the reaction layer; in such instances Eq. 2 is still applicable with different values for the constants A and Q above and below the transformation temperature. 3. All phases that are stable at the temperature at which diffusion occurs will appear in the interdiffusion of two components. In some cases certain of the phases may be too thin to be observed and identified easily. Nonequilibrium phases have never been noted in thick reaction layers; i.e., layers of a thickness that may be discerned microscopically. The relative, thickness of each phase in a diffusion layer is proportional to the concentration gradient and to the rate of diffusion in that phase .4 The reaction layers tend to have a

Jan 1, 1942

By Åke Krukka, Heribert F. Broicher

"The iron ores of the Kiruna Mine in Sweden are of exceptional quality but for the phosphorus content in certain zones of the orebody. The prevention of mixing ores high in phosphorus with those low in phosphorus has always been of significant economic importance. The ongoing introduction of tele-mining and automatic haulage by LHDs requires new means in the field of quality control underground, as the experienced miner as well as the underground laboratory assistant no longer are involved in the process. As of 1998 LKAB has been testing prototypes of LIF Analysers for non-contact and real-time measurement of the phosphorus content of ore being transported by LHDs from the stopes to the respective ore pass assigned to a certain ore quality. The principles of the analysis of laser-induced fluorescence, the different test phases and results are described and conclusions made. With bulk sorting of ore underground the mining engineer supports the efforts of the metallurgist in the processing plant.INTRODUCTIONThe Kiruna Mine of LKAB, Sweden is the largest underground iron ore mine in the world. In the early nineties LKAB decided to develop the Kiruna orebody further down from the 775m main level to a new main level at 1045m. This development programme was realised while in the mineral processing section and in the pellet plant further capacity was added (Wyllie 1996).In addition to deepening of the mine, which opened up 330 million tonnes of ore, the exploitation of the so-called lake ore was included in the future planning, adding another 1 15 million tonnes of mineable ore. At an annual production of approximately 20 million tonnes of ore the Kiruna Mine today looks at a developed ore reserve sufficient for the next 20 years.All of the competitors’ ores traded in the world market are from open pit operations. LKAB compensates for the obvious disadvantages by continuous efforts to make the best possible use of her high quality magnetite ore deposit. This objective is realised by combined efforts in the pellet plant, the mineral processing plant and the mine. Propriety processes, latest big scale equipment and high tech solutions for automation lead to high quality sales products at a reasonable cost."

Jan 1, 2002

By Edward J. Karkoska

The film you see is a slow motion view of a typical half million ton taconite blast at one of Erie's mines. This blast is made up of 220 drill holes and a total of 325 thousand pounds of blasting agent. The second view of the same shot is taken by a remote control hi speed camera located 1500' directly in front of the blast. Shortly you will see some violent camera movement as the air blast shock wave strikes the camera location. As the blasting sequence progresses the rock fly becomes evident, and if you will look closely amidst the clouds of smoke, rock fragments weighing up to 1/2 ton begin to cascade into view. These missles are the chief concern of blast security. The next camera shot at 4000 frames/second vividly describes the primacord firing lines detonating the blast. Travelling at 22,000 ft./sec., this white snake of fire travels to each hole, detonating the blasting agent. Before we get into the matter of blast security, let me locate our operation for those of you not acquainted with Minnesota's iron ranges and tell you something about our company.

Jan 1, 1969

By Z. Y. Hu

This paper reviews the past and presents the present state of industrial minerals in China. The resources, reserve and production of major non-metallic minerals are given. The mining and milling operations are reviewed. The future development and plans of Chinese non-metallic minerals industry are summarized.

Jan 1, 1990