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By P. J. Carroll, H. Colijn

Feeders must be considered an integral part of the over-all bin and feeder system. Improper design of either one of these parts will affect the performance of the whole system. Feeder load, material properties, feed rate, physical layout, and environment as well as first cost determine the selection of feeder type. This paper provides a new method of calculating feeder loads with some experimental data as verification. General design criteria for belt and apron feeder, rotary table and plow feeders are discussed and a special section is devoted to vibratory feeders. Feeders are used to provide a means of control for the withdrawal of bulk materials from storage units such as bins, bunkers, silos and hoppers. This control function can only be performed properly as long as the bulk materials flow by gravity to the feeder in a uniform and uninterrupted fashion. During the past few years various papers have been written and presented on feeders and their application.1-9 This paper will be confined to some specific bin-feeder design criteria such as feeder load and power requirements. Special attention is given to the basic design criteria for vibratory feeders. HOPPER AND BIN DESIGN Feeders must be considered an integral part of the over-all bin and feeder system. Improper design of either one of these parts will affect the performance of the whole system. A lot of effort has been devoted in the past decade to the development of functional design criteria for hoppers and bins.1,10 The integrated concept of bin and feeder design requires quantitative analysis of the bulk material characteristics before the design and the selection of components can be attempted. The design of a feeder system must begin with the proper dimensioning of the hopper outlet to prevent arching or ratholing. The hopper opening should be large enough to allow passage of the bulk solid at the required maximum discharge rate." A feeder can only throttle the flow. FEEDER LOAD DETERMINATION Over the past ten years, there have been various attempts to determine the exact load or pressure on feeders mounted directly under hopper openings. Many designers, however, still consider this pressure equal to the hydrostatic head of material above the opening, and because such pressure would be very

Jan 1, 1969

By K. T. Koone, R. J. Blackwell

One of the more important problems to be solved in designing a miscible flood is related to the size of the solvent bank used. Size of the bank may be critical to economic success. Too large a bank loses money; too small a bank may deteriorate and fail to maintain the miscibility needed for high recovery. An important factor in deterioration of a small bank is permeability channeling. In a highly stratified reservoir, solvent speeds ahead in the more permeable zones and mixes laterally with fluids bypassed in adjacent, low-permeability strata. Numerical solutions have been obtained .for the differential equations that describe the movement of a slug through a two-layer system in which mixing occurs both in the direction of flow and transversely. The solvent slug is assumed to have the same density and viscosity as the resident fluid and the pushing fluid. These solutions have been verified by comparing them with similar concentration profiles obtained in the laboratory in a 36-ft stratified model packed with glass beads. The theoretical study revealed that when the dominant mechanism causing a bank to fail is lateral mixing the bank size needed for a given recovery may increase with length rather than decreasing as the square root of reservoir length, as suggested by one-dimensional mixing theory. From a comprehensive examination of the variables, a generalized correlation is developed that relates strata thicknesses, bank size, fluid velocity, mixing coefficients, system length and simple solvent-resident fluid phase behavior to the area miscibly swept. INTRODUCTION Miscible displacement, or solvent flooding, continues to receive widespread attention as a method for increasing oil recovery over that possible in conventional gas-drive or waterdrive projects. A basic economic requirement in the application of such processes is the use of as little solvent as possible. A basic physical requirement is that enough solvent be used to maintain miscibility. Economics places an upper limit on the size of a solvent slug, and physical considerations establish a lower limit. Consequently, the practicality of any given miscible process requires that the economic limit be greater than the lower limit imposed by physical requirements. Procedures exist for determining the economic limit; however, procedures for determining realistic minimum bank sizes exist for only special reservoir situations. In the past, bank size has usually been selected on the assumption of a piston-like displacement for which only longitudinal mixing is important. This assumption leads to the favorable conclusion that bank size, expressed as per cent of pore volume, is inversely proportional to the square root of length. Collins considered the problem of transverse mixing of solvent with fluids in bypassed zones with the assumptions that no forward mixing occurs and that the concentration is uniform in the permeable stratum of interest. 1 Lauwerier considered a mathematically similar problem in thermal recovery operations.2 Their work suggests the much less favorable conclusion that bank size could be directly proportional to the length or even higher powers of the length. This paper considers the physical behavior of a small solvent bank as it moves through a real reservoir, without imposing many of the restrictive assumptions of past treatments. To facilitate mathematical description, an idealized, two-layer model that permits mixing both laterally and in the direction of flow will be considered. A calculation procedure for solving the descriptive equations will be developed for a displacement involving fluids of equal density and viscosity. In addition, laboratory experiments designed to check the computational results will be described, and the coincidence of calculated and observed results will be discussed. The use of many solutions for a variety of bank sizes, strata thicknesses and characteristic system lengths to develop a usable correlation between

Jan 1, 1966

By Robert B. Parsons

"First down and four to go. In the game Of football, this is not a bad position to be in. However, in this game of political football, it means that there is still a long way to go. The government in Ottawa has concluded an important agreement with one producing province, and now has at least four more provinces to deal with-B. c., Saskatchewan, Nova Scotia and Newfoundland.On September 1, 1981, the federal and Alberta governments took a significant step forward in formulating an oil and gas policy for Alberta and the rest of Canada on signing a comprehensive five-year agreement that covers taxes, prices, incentives and other fiscal matters related to the production and marketing of oil and gas.This month, Tax Notes examines the main features of the agreement, and offers some eye-opening observations of what the new accord could mean for the future of the Canadian petroleum sector in particular and Canadian business in general."

Jan 1, 1981

By Dennis V. Woods, J. Duncan Crone

"In order to determine its capabilities and to aid in the interpretation of fie ld results, a scale model study and field tests were carried out on the Crone borehole pulse electromagnetic (PEM) system. The model results indicate that if a borehole passes in the vicinity of a tabular conductive body, the system will not only detect the presence of the body, but will also return information as to its conductivity-thickness product, size, altitude and position.The effect of variation of these electromagnetic and geometric factors on the shape of the response curve from a borehole PEM survey is displayed by a number of suites of scale-model response curves. These model curves can be used directly as type curves in the interpretation of field results. Field tests of a prototype PEM system provide a check on the scale-model results and also summarize the procedure of interpreting field data using the model type curves.The borehole pulse EM system can be effectively used as a follow-up geophysical instrument for locating and delineating known conductive bodies. It can also be profitably utilized as a primary geophysical exploration tool in areas of deep mineralization below the depth limit of conventional airborne and ground geophysical systems. The probed area of a diamond drill hole in these cases is increased from a 1- inch drill core to a zone extending hundreds of feet from the hole."

Jan 1, 1980

By J. R. Hoskins

Method - A direct approach to instrument users, initially by letter and later by telephone or personal contact was made. The resultant data was compiled to give specific use information on the seven instruments. During the course of the study attempts to evaluate the Griswold Gage were abandoned when it became apparent that the gage was not being commercially produced. One company is developing the gage for its own use. The information presented is the result of over 1200 inquiries.

Jan 1, 1973

By Robert van Hille, Alison Lewis

The precipitation of a selection of metals from both a synthetic and an actual metal-rich effluent was investigated. The experimental aspects of this study were carried out in a two-stage process consisting of a pre-treatment clarifier and a fluidised bed (pellet) reactor. Each unit operation in the two-stage process was investigated separately. The pre-treatment clarification stage at pH ˜ 5 resulted in a 99.9% removal of iron and 97.3% removal of aluminium. The pellet reactor was used to precipitate nickel as nickel carbonate from a pure stream and a removal efficiency of 99.6% was achieved. The high local supersaturation at the reagent inlet points caused the formation of a large amount of fines, but these agglomerated onto the pellets up the length of the bed. For copper precipitated as copper sulphide from a pure stream, a maximum removal efficiency of 92% was achieved. The high local supersaturation at the reagent inlets also caused the formation of a large amount of fines, but the extremely sparingly soluble nature of copper sulphide meant that the fines were not agglomerated up the length of the bed. For removal of cobalt as cobalt carbonate from an actual stream, a stable cobalt removal of only 60% was achieved. This was found to be due to the presence of magnesium, which reduced the cobalt precipitation efficiency through the formation of the magnesium bicarbonate ion.

Jan 1, 2003

By Allan R. Ide

It is a great pleasure for me to speak-before such a prestigious group as the American Institute of Mining, Metallurgical and Petroleum Engineers. The substance of my talk today is the handling of coal and petroleum coke: their characteristics and environmental problems, and how we were able to correct the problems, prescribe the cure and enjoy the benefits. When coke first became a by-product derived from the oil refineries everyone would have been very happy if someone had offered to take this pro- duct off their hands. Unfortunately, there was no market at that time, and no one seemed interested. Soon thereafter, it became a sellable product and began to be shipped to many countries in the world. This was when all of the pollution problems began. I will be talking briefly about some of these problems and showing a short film on this subject afterwards.

Jan 1, 1984

By N. A. Warner

To filly secure the environmental and social acceptability benefits of making a sulphide smelting facility and its ancillary sulphuric acid plant or other means for fixing sulphur, a virtually zero gas emission operation, it will be necessary to utilise exclusively technically pure oxygen. The strategy proposed for preventing the smelter from overheating involves highly efficient energy transfer by promoting sulphur trioxide formation at a relatively higher temperature than normal. A closed-loop gas circuit uses an eductor system actuated by the process oxygen to recirculate sulphur trioxide and unconverted sulphur dioxide back to the smelter, the endothermic dissociation of sulphur trioxide becoming a major contributor to the removal of excess heat. The only gases leaving the system relate to the bleed of nitrogen impurity introduced in the tonnage oxygen.

Jan 1, 1998

By Jillian Spindura

This work investigates the carbothermic reduction of the complex sulphide mineral, pentlandite, in the presence of lime. The effects of change in temperature and the use of different carbon sources are studied and the role of these variables on the reducibility of pentlandite mineral is discussed. The microstructures of the heat-treated pellets are examined using X-ray diffraction and scanning electron microscopic techniques. The latter analytical method also allows any variation in the morphology and composition of the metallic phases formed, with temperature, to be considered. The kinetics of the reduction process is studied and the magnitude of the overall activation energy is determined from the plots of percentage reduction versus time.

Jan 1, 1996

By VIVEK KUMAR HIMANSHU, Murari Prasad Roy, Kaushik Dey, Rakesh Kumar Singh, Ashish Kumar Vishwakarma

Sublevel stoping is commonly adopted method in underground hard rock mining. Proper planning and its execution is the key requirement for stope extraction using this method. The stope extraction has been a challenging task since decades. The major reason being the unavailability of free faces as compared to open cast bench blasting. The geological and geotechnical parameters changes gradually even within the stope itself. So the blast design parameters should be planned according to the scenario of upcoming ring. Blast design parameters like burden, toe spacing, inclination of blast holes, diameter of blast holes, charge density of explosive etc plays an immense role in rock damage. For the proper breakage of rock, the movement of burden is prime objective. To study this, explicit dynamic based modeller of M/s Ansys was used. The burden values were varied from 20-65 times diameter to assess optimum burden value during the study. The models were simulated for the rock having 35 MPa uniaxial compressive strength and 102 mm blast hole diameter. Altogether three holes were blasted having hole depth 14-14.5m. The blast design parameters and respective blast induced ground vibration has been measured at the experimental site. Core sample of the rock of experimental site has been used for the evaluation of geotechnical parameters. These geotechnical parameters were inserted into the simulation model. The volume of rock excavated along free face has been calculated in each model. It has been found that the burden value can varies from 35-40 times blast hole diameter (3.6-4.1m) to achieve greater volume of rock along the free face for 102 mm blast hole diameter and rock of 35 MPa uniaxial compressive strength.

Feb 6, 2023

By Maylin Mendoza

El presente estudio tiene como objetivo caracterizar mediante el uso de la litogeoquímica, la serie magmática y la roca encajonante que tuvieron lugar en la formación del VMS de Cerro Lindo; a la vez se realizó litogeoquímica de alteración para determinar la relación entre mineralogía, litogeoquímica e intensidad de alteración, obteniendo como resultado, vectores hacia el centro del sistema. La finalidad primordial es llevar esa información 2D de los diagramas litogeoquímicos a un enfoque 3D, y así establecer correlaciones con otros controles de la ocurrencia mineral (estructurales, geofísicos, geoquímicos y litológicos).

Sep 30, 2022

By L M. Zhang, T H. Xu, J Zhao

Blasting is one of the most commonly used strategies for excavation in civil and mining engineering. Yet blasting can also bring along such undesirable effects as ground vibrations and soil disturbance. Numerical analysis is a powerful tool for estimating the effects of blasting and improving blasting design. In this research, a constitutive model for sand is proposed for the numerical analysis of blast-induced ground motions and wave propagation in soil mass. In the model, three model surfaces, ie the critical surface, the dilatancy surface and the bounding surface, are defined following the bounding surface hypoplasticity framework. The strain rate is included explicitly into the model formulations so that the proposed model is valid under high strain rate loadings caused by blast-induced vibrations. The performance of the proposed model is validated by the simulation of drained triaxial compression tests conducted on a crushed coral sand under different strain rates.CITATION:Xu, T H, Zhang, L M and Zhao, J, 2014. A bounding surface model for sand subjected to blast-induced vibrations, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 201–206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By R. D. Studer

"The Snow Lake massive sulphide deposits are hosted by Aphebian volcanic rocks of the Flin Flon - Snow Lake greenstone belt, which in this area were deformed and metamorphosed to the amphibolite facies during the Hudsonian orogeny. All the known deposits occur in felsic rocks a short distance below the contact with an overlying mafic rock unit.The Stall Lake copper deposit occurs close to the top of an explosive felsic volcanic sequence. Rocks stratigraphically underlying the deposit have been hydrothermally altered by the mineralizing fluids. The sulphides were probably deposited from submarine volcanic vent(s) on the flanks of a felsic dome. The ore has been tightly folded, flattened and elongated parallel to the northerly trending lineation of the surrounding rocks during the several periods of deformation. Strike lengths of the lenses range from 60 to 300 feet and plunge-to-strike ratios are as much as 15:1.Ore lenses I to 4 typically consist of massive coarse-grained pyrrhotite, chalcopyrite and pyrite. A stratigraphically higher lens differs in that it contains fine-grained pyrite and chalcopyrite, with an increase in sphalerite toward its hanging wall. The No.4 orebody has a distinct footwall alteration zone characterized by brecciation and abundant chlorite-staurolite- garnet schist, with minor kyanite, anthophyllite, cordierite and anhydrite, as well as sulphide minerals. Chemically, the alteration zone is distinguished from the unaltered felsic rocks by Na20 depletion and Mg-Fe enrichment"

Jan 1, 1982

By John De La Vergne, Morri Medd

"This paper describes the sinking of a circular concrete ventilation shaft through 110feet of water-bearing overburden. The brine circulation freezing method was used to stabilize the walls during excavation. In order to take advantage of the cold winter weather, a custom-built heat exchanger (natural radiator) was installed in place of the standard mechanical refrigeration plant.IntroductionIn the late fall of 1979, Les Mines Selbaie awarded a contract to the firm of 1.S. Redpath Limited to sink a ventilation shaft on its property in northwestern Quebec. The shaft was to be sunk through 110 feet of water-bearing overburden and approximately 90 feet of rock to a final depth of 200 feet below surface. The water table was measured at 16 feet below the surface elevation.After examining the soils report and diamond drill core from the shaft area, Redpath came to the conclusion that freezing was the best way to stabilize the overburden for sinking. LocationThe mine site is 420 statute miles due north of Toronto, just east of the Ontario/Quebec border (Fig. 1). Access to the site is provided by a development road built by the Quebec government from the Matagami/lames Bay Highway. History of Ground Freezing In the Mining IndustryIn 1862, shortly after the development of mechanical refrigeration, a mine shaft was sunk through an artificially frozen water-bearing formation in the United Kingdom. The first application of ground freezing in North America was for a Michigan iron ore shaft in 1888. Since that time, the freezing method has been used to sink hundreds of shafts throughout the world. Its best known application was to sink sixteen shafts through the Blairmore Formation in Saskatchewan.The same method has been used in every case. It involves chilling a calcium chloride brine solution and circulating the brine in concentric pipes, spaced between 3 and 6 feet around the shaft perimeter and usually 4 to 5 feet from the limits of the proposed shaft excavation."

Jan 1, 1982

By Dean E. Bluman

The Bureau of Mines investigated the convective heat transfer coefficients for recirculated suspensions of 30-micron glass beads in inert gas. Coefficients for the suspensions were not significantly higher than coefficients for the pure gas. Reynolds numbers of the suspensions were 20,000 to 35,000; solids loadings ranged from 0.0 to 0.7 pound per pound of gas. Comparison of the results with published data showed the direction of heat flow to have no effect at the test conditions.

Jan 1, 1967

By John C. Smock

The rich deposits of magnetic iron-ore in the Highlands of northern New Jersey attracted the attention of iron-workers at the time of the earliest settlements in that region. The outcrops of the oreshoots at the Dickerson mine, at Mount Hope, and at Hibernia, in Morris county, and at Ringwood, in Passaic count,y, which were doubtless such as would lead to discovery, location and development of nearly all the large iron-mines in that part of the State, appear to have had their beginnings where the ore cropped out on the surface or where it was scarcely concealed by a thin mantle of earth. In the early history of New Jersey iron-mining, the careful explorations and surveys made by the agents of the famous London Com-

Jan 1, 1892

By Paul Biggs

This report presents information on 77 waterflood projects in 31 Montana oilfields. The study shows the locations of the projects, the sources and amounts of injection water, and the results in oil produced. Waterflooding, a secondary recovery technique, began in Montana about 40 years after the initial oil discovery in 1920. Often, the difference between water disposal by injection and pressure maintenance operations is not clear. Water injected at the projects in 1973 was 157.7 million barrels. In 1973, the 31 fields having waterflood projects produced 28.3 million barrels of oil valued at $88.4 million. Both in volume and value, this represents over 80 percent of the State's 1973 oil output. The projects are making possible the recovery of additional oil, thus contributing to the conservation of oil and lessening the impact of the current oil shortage.

Jan 1, 1976

By D. R. Dolinar, J. Pablic, D. C. Oyler, T. P. Mucho

At a mine in central PA, high horizontal stresses have caused long running roof falls resulting in hazardous conditions for the miners and the premature abandonment of panels. Because of these conditions, the mine requested assistance of the National Institute for Occupational Safety and Health (NIOSH) in utilizing the 'advance and relieve method to mitigate the affects of horizontal stress on the mine roof. "Advance and relieve" mining involves the removal of a pillar or a portion of a pillar during development, thereby creating a cave along one side of the panel. Following cave development, the horizontal stress is relieved over the workings adjacent to the cave in the active panel. The mine has used this system in three panels with a significant reduction in stress damage and no large roof falls.

By Denise Y. Dizon

The objectives of this study were to document the hydrologic impacts of longwall mining on streams, identify the factors affecting the extent of stream dewatering, and develop empirical trends to predict the extent of dewatering and recovery of streams in advance of mining. This study on stream impacts is a companion to a stud; conducted on ground water impacts from longwall mining, which was done as part of the same research project at the' same locations and times. The study areas are three mine sites in north- central West Virginia. Mine A, located in Upshur County, has relatively thin mine overburden under the valley streams (105-115 feet). Stream monitoring there continued the earlier work of Cifelli and Rauch (1). Stream dewatering was severe with streams often going dry over the longwall panels during baseflow conditions. The lost water was probably flowing to the mine. Dewatering began in streams over the mine entry areas adjacent to the panels and as much as 380 feet from the nearest panel edge. The angles of dewatering influence ranged 22 to 72 degrees with respect to the nearest mined panel edge. Discharge then typically increased as the streams- flowed across the panel edge, but then decreased again over the panels. These streams were often ponded by local reversals in hydraulic gradient caused by land subsidence, and often dried up after flowing a few hundred feet across the panels. This occurred over panels that were previously mined up to eight months before. Mine B, located in Monongalia County, has relatively thick mine overburden (475-485 - feet) under the major stream. Stream dewatering was severe there during warm season baseflows, with complete dewatering occurring then over the longwall panels. This dewatering occurred over mined panels up to five years old, probably in response to a major anticlinal axis lineament and fracture zone in the stream valley. Mine C. located on the West Virginia -Pennsylvania border, has relatively thick mine overburden (about 585-630 feet) under the monitored streams there. stream dewatering was only partial, and these streams typically recovered their lost discharge downstream of the mine, indicating that lost water was not recharging to the mine. Only longwall panels less than one year old were associated with stream dewatering.

Jan 1, 1990

By T. G. Carter

"This paper traces the introduction and use of fire-resistant (FR) fluids in hydraulic systems at underground mines in British Columbia. Reasons are given for the decision to make compulsory the use of such fluids in underground mines after January 1, 1975 by provincial government legislation. Examples are quoted of fires caused, or supported by, mineral oils which have resulted in loss of life and property.The basic principles of hydraulic systems are reviewed in order to present the effects of changing a system operating on mineral oils to one which must operate on FR fluids. Approximations of the cost of system conversions are given for certain machines and a brief survey is made of the various pieces of underground equipment which contain hydraulic systems operating on FR fluids.IntroductionIn 1948, Admiral Ben Moreel , who was then president of Jones and Laughlin Steel Corporation in the United States , wrote:""Although safe and healthful working conditions can be justified on a cold dollars-and- cents basis, I prefer to justify them on the basic principle that it is the right thing to do. ""(1)This paper will outline the introduction and use of fire resistant fluids at mine operations in the Province of British Columbia. That it was the right thing to do in enhancing the safety and well-being of every person employed at the mines was the prime consideration. That it may be justified on a cold dollars-and-cents basis is left for the reader to judge. The prime purpose of this paper is not so much to trace the efforts made by the individual mines to successfully introduce and use fire-resistant (FR) fluids in hydraulic systems, but to present an over-all picture of what occurred, in a collective sense, at the majority of mines which have ended up with a working FR fluid system. The problems attendant to the introduction of an FR fluid will be recounted in a manner which, it is hoped, will prove useful to those contemplating system conversions. Because the predominant fluid now in use is an invert, or water-in-oil. emulsion, this will be the FR fluid considered.Fluid Loss from SystemsThe quantities of various fluids required for use in hydraulic systems are extremely high. This statement in itself may appear to be redundant in that the capacities of the various systems should demand that a fixed amount of fluid is required for the initial filling of a system, with a further amount of fluid scheduled for use during subsequent fluid changes, i.e. at the recommended change intervals . If only this were the case!"

Jan 1, 1981