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By CLARENCE G. SMITH

Prior to the actual development of an oil property it is difficult to determine the quantity of oil under the property and the rate at which this oil can be brought to the surface-factors that determine the ultimate value of the property. Consequently, there has been much confusion in devising accounting systems that, during the entire life of a property, will show costs and profits from which the producer can determine whether his property is being worked at a profit or otherwise. The Bureau of Mines publishes this report in recognition of a distinct need for a simple treatise on accounting methods adapted to the peculiarities of the petroleum industry. Probably many companies operating oil wells are not fully acquainted with details important to the welfare of their business, because their account books fail to furnish them with exact and adequate data. With the accountant rests the responsibility of providing the management with reports setting forth the details of the business expressed in fitting terms as well as in dollars and cents. These reports are a means whereby efficiency may be maintained, waste prevented, oil obtained and sold, and money suitably reinvested. They also enable a concern to study the progress of its business in order to conserve to the utmost the possible benefits from an exhaustible deposit of mineral wealth. When managements realize the extent of the waste at their properties more attention will be given to the character of the accountancy records. Herein are presented descriptions and discussions of balance sheets, profit-and-loss statements, and bookkeeping methods peculiarly adapted to the oil business. As far as possible, technical phrases have been omitted in order that those not familiar with accounting terms may be able to follow the subject matter. The systems of keeping books outlined in Chapter X have all been found practical. For brevity as well as clearness the major part of the work refers to the company operating only one property.

Jan 1, 1917

By W. A. Gow, H. H. McGreedy

It is believed that many of the problems encountered in the operation of gold cyanidation plants are difficult to resolve due to the lack of sufficient and reliable in-formation regarding the variations and actual values of operating variables at any given time. The application of instruments to monitor the more important variables in the cyanidation process should result in more efficient plant operation and a better understanding of the process. The use of pH and conductivity sensing devices for alkalinity measurements, a monitor to determine the dissolved oxygen content of plant solutions, a continuous cyanide titrator and sonic control of grinding circuits are discussed. Although the discussion is oriented toward the cyanide process, much of the paper is applicable to other ore treatment operations.

Jan 1, 1966

By Gordon M. Pugh, David G. Rasmussen

INTRODUCTION Sublevel long-hole stoping is a large tonnage stoping method that may be used when there is a fairly com¬petent straight vein and the walls will stand with little support. It is a method that lends itself to a high degree of mechanization. Two variations of the method are illustrated in Figs. 1 and 2. Fig. 1 illustrates development typical for a 3-m (10-ft) wide vein. Initial development is by a lower haulageway, which may be either track or trackless. A two-compartment raise is driven in the footwall of the vein. At about 12 m (40 ft) above the main head¬ing, a footwall scram is driven and pockets through the vein are cut on 7.6-m (25-ft) centers. Each of the sub¬level blocks selected in this example is 45.7 m (150 ft) long by 12 m (40 ft) high. Stoping starts at the slot raises at stope endlines and retreats to the timbered raise. This retreat sequence starts on the lowest sublevel and the opening cut is blasted into the slot raise. This retreating system is used in order to provide a good safe back over the miners working in any given sublevel. A crawler-mounted down-the-hole or conventional pneumatic drill puts the holes down from one sublevel to the next on any desired drill pattern. Gravity flow brings the broken ore down to the scram level. The illustration shows a large slusher mounted at the timbered raise and slushing from the pockets back to the raise chute. Development of the ore block in Fig. 2 is typical for a 5.5-m (18-ft) wide vein. Initial development is by a trackless heading driven in the footwall of the vein. Pockets are then put into and through the vein on 7.6-m (25-ft) centers. For ease in using trackless rubber tired mucking equipment, these pockets are crosscut to the vein at approximately 1.04 rad (60°) rather than per¬pendicular. A two-compartment timbered raise is driven down from one level to the next. Endline slot raises are again put through from level to level. Each of the sub¬level blocks selected in this example is 40-m (130 ft) long by 33.5 m (110 ft) high. Stoping starts at the slot raises and retreats back to the timbered raise. Long holes are drilled from one sub¬level down to the next by starting between the lowest pair of sublevels and then working up the ore block. Mucking out of the pocket drawpoints is accomplished by rubber-tired load-haul-dump (LHD) units which then dump into a centrally located orepass.

Jan 1, 1982

By John W. Rushton

Maintenance and inventory are usually the last items considered in mine development. They need to be addressed properly and early. The micro-computer brings sophistication within the reach of even the smallest mines. Maintenance and inventory programs, if properly installed, will reduce costs 15 to 25% and allow management time to address the mining and metallurgical problems at start up. Shops and warehouses are rarely designed properly. Large engineering firms spend 5 to 20 times more than is necessary for first class facilities. There is an optimum design, size, and layout. Take the time necessary to assure you get the right people, programs, and facilities in that order. Maintenance, inventory, and inventory control must be addressed early if a small mine is to have a chance at optimizing costs during the first two years of operation. This is hard work and is usually put on the back burner until the mine is in some degree of trouble. Hiring an experienced maintenance superintendent is important but it is not the complete solution. Maintenance systems, design of facilities, and use of computers are not skills that maintenance people usually have. In addition, the work of ordering spare parts and working with erection people is a full time job and any maintenance people on site during construction are quickly recruited. The end result is that few mines start up with an adequate Maintenance or Inventory System in place. The months, and in some cases years, that the mine attempts to operate without a system are both painful and expensive. Designs of successful integrated maintenance and inventory programs are virtually 100% supported with some outside assistance. Our system is the approach that we are most familiar with and this paper will isolate how Rushton International would go about setting up systems and designing support facilities. Micro-computers are the only way for a small mine to go. ~ini-computers cost more originally and operating costs are many times higher than even the most sophisticated micro system. Micro- computer software is developed further and recent advances in hardware makes medium priced units equal to most mini's in RAW COMPUTER POWER. Mines in general, and especially small mines, have no need for main frame power. MAINTENANCE A good maintenance program has: 1. Equipment Master List a. Equipment Detail Reports 2. Work Order and Backlog Control Program 3. Component Control Program 4. Tire Program 5. Wear Materials Program 6. PM Control Program 7. Maintenance History Program 8. Performance Program We also track miscellaneous items such as MSHA training and inspections, timekeeping, etc. Rather than going through the program step-by-step, it makes more sense to go through a typical Maintenance Day and show how the programs are used. The first thing maintenance supervision needs to know is "how we are doing." We

Jan 1, 1987

By J. Winters, L. Vos, C. Canoo

Committed to a sustainable development of zinc applications, Union Miniere is investigating processes for the minimisation of waste and residues originating from the classic hydrometallurgical zinc process. In that context, Union Miniere has developed a method for the cold inertisation and solidification of goethite, the Graveliet® process. The result is a hard and inert gravel that can be used in the building industry. During the past two years, a pilot plant for the production of Graveliet® has been built and operated. In the present paper, the Graveliet® process and the pilot plant are described after which the properties of the produced gravel are discussed, from both a mechanical and an environmental point-of-view. Graveliet fulfils the criteria for use as a secondary building material. The GravelietJ process is a viable technology to avoid stockpiling of goethite residues and it thus assures the long-term development of the hydrometallurgical zinc process.

Jan 1, 2000

By Robert Halupka

The industrial minerals sector represents a broad range of products involving a variety of technologies serving a diversity of markets and end uses. Unit values of products vary widely, reflecting the peculiarities of each product/market sector. Generalizations are therefore understandably difficult to make and borrowers may need to take extra time to "educate" lenders on the key aspects of their business and industry sub-sector. This paper will examine the factors and the thinking that lenders apply when considering financing proposals to companies in the industrial minerals sector. If you understand the lender's perspective and their concerns, then you can make better use of your own time and resources when arranging financing for your company or project.

Jan 1, 2001

A Process for the Flotation of Chrysocolla

Sep 13, 2010

By D. K. Chibwe, P. Taskinen

"Typical operation of industrial Peirce-Smith converters (PSCs) used in copper smelting results in several common phenomena such as excessive splashing, slopping, tuyere blockage, and low converter campaign life due to high tuyere line refractory erosion. These phenomena give rise to an inefficient operation from both a process and an energy perspective.This investigation presents numerical and physical models of flow patterns, mixing, solid-liquid mass transfer, and slag-matte phase distribution in a slice model of an industrial PSC. For physical simulations, a 0.2-scale cold model was developed. Water, kerosene, air, and sintered benzoic acid compacts were used to simulate matte, slag, injected gas, and solid additions into the PSC. The two- and three-dimensional numerical simulations of the three-phase system were carried out using volume of fluid (VOF) and realizable k- e (RKE) turbulence models to account for the multiphase and turbulence nature of the flow respectively. These models were implemented using the commercial computational fluid dynamics numerical code FLUENT.Both numerical and physical simulations were able to predict, in agreement, the mixing and dispersion characteristics of the system in relation to various blowing conditions employed in the investigation. Measurement of mass transfer characteristics conclusively indicated that fluid flow in the PSC is stratified. Both blowing configuration and volume of slag in the converters were found to have significant effects on mixing propagation, wave formation, and splashing.The splashing and wave motion in these converters are known to cause losses of metal/matte and potential production time due to the requirement for intermittent cleaning of the converter mouth, resulting in reduced process throughput. To prevent these losses and hence to increase process efficiency, we propose a combined blowing configuration using top lance and lateral nozzles. The numerical simulations were conducted on combined, as well as lateral, blowing conditions. In comparison, the recent results of the combined blowing concept were found to be encouraging."

Jan 1, 2014

By Enzo Angeles, Desmond Nanchengwa, Lee Julian, Julian Ruiseco

Since the early 1980s, surface hard-rock mining companies have searched for a blast movement model to enable grade control optimization efforts. Significant time and money were spent attempting to create blast simulations to aid post-blast grade control. Despite nearly 40 years of effort, practical blast movement models remained elusive until computing power reached levels that make real-time simulation possible. From the mid-1990s, mines have been creating in-situ grade control polygons and translating the polygon nodes horizontally to account for blast movement. In many cases, objects are placed in the blast volume and located post-blast to provide local vectors for these node translations. This method was always a compromise between practicality (2D) and reality (3D), but it was the only viable solution that matched the needs of operations. This study considers 21 blasts and evaluates the incremental value achieved by new processes unlocked through 3D modelling, while investigating challenges, limitations, and opportunities for each method.

Jan 1, 2023

By M. G. Atmore

As is usual when preparing for this type of occasion, I looked back at the subjects covered by my predecessors when they assumed the presidency of this Institute. You will appreciate that, in the eighty odd years since the Institute was founded, the diversity of subjects has been very great. In almost all cases it is quite natural that the speaker should have chosen a topic of special interest to him and one in which he was particularly knowledgeable.

Jan 1, 1979

By John N. Murphy, Edward F. Fries

The availability of fast, low-cost computer hardware and advanced software is opening new opportunities for minerals extraction and processing. Programmable Logic Controllers (PLC's) are currently used extensively in the minerals industries; this paper looks beyond PLC's and that vintage of “computer control”--it looks toward what the authors see as new in the next five years. Topics covered include expert systems, neural networks, intelligent signal processing, and hierarchical controllers as applied to mining and mineral processing operations.

Jan 1, 1993

By L. K. Smith, E. M. de Kock, J. van der Walt

A unique and systematic approach for analysing alternative methods of ventilating and cooling large hot mines is presented. The important factors that have a bearing on ventilation and cooling requirements and practices, such as air flow through the mine, geographical distribution of heat loads, micro ventilation considerations etc., are dealt with. Analysis of these leads to the definitive ventilation and cooling strategies, air and water process design, detail specifications and design of associated plant and equipment.

Jan 1, 1982

By McMahon DW

The major components of a mineral reserve estimate for project development purposes are described with respect to sampling, geology, estimation methods, mining factors, metallurgical factors, environmental factors, financial and other factors. Each of these components impact to varying degrees on the recoverable metal or product of a new mining project. The evaluation of a project is a complex process involving the best the profession can provide in terms of geological understanding, engineering ingenuity, metallurgical skills and financial evaluation.

Jan 1, 1983

By Mostyn G. R

An important problem in rock engineering is to control the properties of artificial rock. A compaction technique for casting artificial rock specimens with controlled properties is described, i.e. using a compression-testing machine to compress the mixture. Uniform density is necessary to achieve uniformity of properties of the specimens, and uniform density can be obtained by using the specific pressing method presented. Rebound and borax content are important to the technique and have been studied as well.

Jan 1, 1992

By H North, J Barringer, S McNeill, D Pairman

Models of ground surface elevation, slope, aspect, curvature, roughness, deformation, as well as other features are gathered together in the term Digital Terrain Model (DTM). DTMs can be generated from a wide range of technologies such as ground surveying, aerial and satellite imagery, including both active and passive sensors. Some elevation derived parameters, such as roughness and slope, can be measured directly using innovative active sensor technology and smart processing, rather than via traditional processing of elevation information. Such models are used as part of a visual interpretation process, and increasingly for computer-assisted analysis using visualisation technology. There is an ever-increasing demand for DTM information to be used in the mineral exploration and mining industry, and consistent pressure from industry to develop models of higher spatial resolution, higher accuracy, and better overall reliability, regardless of the world-wide location of interest. This presentation will survey the range of techniques available for DTM generation, including active (LIDAR, SAR interferometry and differential interferometry) and passive (optical or SAR stereo) methods, as well as interpolation methods (contour or structure interpolation), and the economic placement of these various techniques in the local and regional context. The research issue oftrue-ground elevation models and slopes is also addressed, using LIDAR and SAR polarimetry as signpost technologies. Particular emphasis will be given to the strengths and limitations of new data sources that will, over the next few years, make the acquisition of elevation models of remote regions of the world inexpensive and relatively accurate.

Jan 1, 2000

By A. Festa

Secondary crushing often gets good press for its increases in energy efficiency and SAG milling rates but for a project considering this option the proposed benefits soon get overshadowed by implementation concerns. Reverse engineering from the published case studies is risky unless the reader understands the drivers impacting stability and operability of the circuit. This paper discusses the features of secondary crushing for Greenfield and Brownfield SAG mill grinding circuits. It is the author?s view that secondary crushing rarely adds value to a Greenfield project and restricts future expansion. Its application is best retro fitted to Brownfield operations where the benefit gained for capital expended is excellent. Two case studies are presented to reaffirm these statements. The first case study shows that the implementation of partial and total secondary crushing increases SAG mill power efficiency and it offers substantial incremental increases in milling throughput with staged capital investments for the crushing and grinding circuits respectively. The paper provides a critical analysis of process conditions for secondary-crushed grinding circuits, with particular emphasis on Brownfield circuit retrofits. Furthermore, the second case study quantifies the economic impact of secondary crushing on circuit design for plant start up and it illustrates the limit imposed on plant expansion.

Feb 23, 2014

To provide a simple means for rapidly checking methane concentrations at working faces in coal mines while remaining under permanently supported roof. The Approach: A light telescopic probe, through which a gas sample can be pumped Into a methanometer, has been developed. See Figure 1 [ ] How It Works: The telescopic probe consists of sections of small stainless steel tubing encased in sections of lightweight fiberglass tubing. When fully extended the probe is almost 19 ft. long; fully closed it is approximately 5-1/2 feet long. It can be used In either of these positions as well as at intermediate extensions. An approved methanometer is clamped to the probe by a support bracket.

Jan 1, 1975

By R Burke, G Ramage, C Donnelly

Over the decades, Redpath has undertaken a multitude of tunnelling and underground excavation projects for civil and mining clients both domestically and internationally. These projects have been undertaken through varying strata conditions with differing excavation methods in remote locations and in central business districts.With the recent turbulent nature of the global financial environment, project drivers have been challenged with the emphasis being placed on methods to gain early access to orebodies, rapid development techniques, lower capital costs and reduced labour requirements to name a few.A number of mining companies seeking to achieve these objectives have commenced the journey to better understand the operational constraints, challenges and opportunities that may be available with the use of alternative excavation methods.The development of safe and effective alternative excavation methods that comply with both domestic and international mining legislation and regulatory requirements is a challenge the industry needs to embrace. Given the current cost pressures being faced by the Australian mining industry, some alternative excavation methods offer the potential for longer term sustainability and rapid development of resources.More recently work has been undertaken on a project that challenged the norm and implemented an alternative excavation method with the use of an excavator with a rotating drum cutter head.This paper will review this recent project and provide technical and operational insight into some of the challenges faced in implementing an alternative excavation method in the metalliferous industry.CITATION:Donnelly, C, Ramage, G and Burke, R, 2014. Challenging the norm – alternative excavation method in mining, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 187–190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By W. Spencer Hutchinson

IT is the purpose of this paper to describe a method used to determine the corundum contents of samples of hard crystalline gneiss containing both corundum and red garnet. A chemical analysis of the rock for alumina would not fix the amount of corundum because at least three other constituent minerals of the rock, mica, feldspar, and garnet, contain alumina combined with silica. Following are the principal minerals found in the samples, together with their specific gravity and hardness as given by Dana:

Jan 6, 1913

The criterion for assessing the accuracy of coal reserve estimates proposed by Philip and Watson (1982) is criticized.Following Royle (1977), it is suggested that the global estimation variance found by geostatistical methods is more appropriate.This method is applied to coal data from the Bowen Basin. This shows that two factors (the inherent variability of the variable under study and the total number of drill holes) have more influence over the accuracy of the reserve estimate than the form of the drilling pattern. Comparisons between the relative errors for different sized regions demonstrate that the spacing between drill holes is of secondary importance. The dominant factor is the total number of holes.Comparisons between the relative errors show that some variables such as sulphur need a much denser sampling than the others to obtain the same level of precision.

Jan 1, 1983