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By H. Mullani

We have in southeast Kansas a variety of soils underneath which are a variety of subsoils compressed into what is commonly called “ hard pan.” These soils are of six types, ranging from a clay to a sandy loam. The surface soil in Cherokee County and Crawford County, of whatever quality or type is, generally speaking, from 6 to 12 inches in depth. The so-called “hard pan” ranges from the native grass roots to a depth of from 2 to 12 feet, and in some places even deeper than that.

Jan 1, 2010

By M. Kuchta, A. Newman

LKAB’s Kiruna Mine, located above the Arctic Circle in northern Sweden, is the second-largest underground mine in the world today. The orebody is a world-class high-grade magnetite deposit, from which three raw ore products are extracted. We use mixed integer programming to determine a production schedule, i.e., which production blocks to mine, and when to start mining them, so as to minimize deviation from planned production quantities while adhering to the operational constraints of the mine. The resulting model contains thousands of binary variables and a commensurate number of constraints, precluding us from obtaining a schedule in a reasonable amount of time. We describe a method that builds on prior, related work, to expedite solution time. Keywords: underground mining, production planning, optimization, integer programming

Jan 1, 2003

Processing of Hard-to-Treat Copper Ore and Flotation Middlings Using Chemical Treatment

Sep 13, 2010

By Deon van Tonder, Chuck Edwards

"Solvent extraction is used in many acid leach uranium circuits to upgrade and purify the uranium bearing solution prior to final product precipitation. A number of strip options are available to recover the uranium from the loaded organic. This paper compares some of these options on the basis of typical capital and operating costs for both the solvent extraction circuit and downstream uranium processing, and also considers other related issues. The aim is to provide an objective comparative assessment of these options that could be used as a qualitative guide in process selection or improvement.INTRODUCTIONIn the 1950s the uranium industry was the first industry to adopt solvent extraction (SX). Since then, the flow sheets have advanced. Notable was the introduction of tertiary amine extractants by General Mills during the late 1950s and 1960s (Mackenzie, 1997; Mackenzie, 2005), which is still today considered ‘state of the art’ technology. Initially solvent extraction was done in combination with ion-exchange, such as in the Eluex flow sheet, followed later by the adoption of direct solvent extraction from pregnant leach solution (PLS). From a strip-precipitation perspective ammonia strip followed by ammonium diuranate precipitation was widely adopted as the norm in the uranium industry. More recently alternative strip systems have been receiving increasing attention due to the environmental, health and safety issues associated with ammonia and the resulting calcined uranium oxide product. This paper explores some of these alternative options in comparison with the ammonia route.It is important to acknowledge that each operation is unique, and therefore the information and philosophy outlined in this paper serve to provide a general guide that can be potentially applied and adapted to any site or project."

Jan 1, 2013

By Arthur E. Morris

Fifty years ago when Professor Yazawa began his career, the field of process simulation and modeling was in its infancy. Since then, tremendous progress has been made in our ability to model metal production flowsheets from mine to refined metal. This progress has come about by parallel developments in basic understanding of process chemistry and in computational techniques, This paper will review the progress made in process understanding and modeling in lead, zinc, and copper metallurgy from its inception to the present, and the role of Professor Yazawa's work in furthering this progress. Specific examples will be given for the sintering of lead concentrates, slag fuming, zinc concentrate roasting, flash smelting of copper, and pyro-extraction of zinc. Factors limiting further progress will be described.

Jan 1, 2003

By J. H. Howard

The purposes of this report are to summarize the findings of the Committee on the Challenges of Modern Society Non-electrical Project (a working committee of the North Atlantic Treaty Organization) and also, thereby, to provide an introduction and review of the current situation regarding non-electrical applications to those who are interested in the subject.

Jan 1, 1975

By Staff

One hundred thousand miles of flying over the North country without a single air casualty; much of it over virgin territory probably never before visited by white men; some of it over regions that abound with possibilities for minerals; all of it effective, for exploration and the establishment of bases and supply-stations, and for the carrying of men and their tools and provisions- this, briefly, is the record of Northern Aerial Minerals Exploration, Limited, a Canadian company organized Jess than nine months ago, which has been functioning, without interruption, during spring, summer, and now into winter. Our planes have ranged from the Alaskan boundary on the west to the Labrador coast on the east, and from the Transcontinental railway north to the Arctic circle. Our prospectors, carried on trips of hundreds, and occasionally thousands, of miles, have gone over large sections of country which were never before explored, and at the end of the prospecting season the Company finds itself in possession of several groups of important gold claims, which look most promising. In addition to this, we have been in contact with deposits of almost every known mineral.

Jan 1, 1929

By Robert F. Mehl

Jan 1, 1944

By Robert F. Mehl

Jan 1, 1944

By T. R. Rehak

Blasting operations are an essential element in the recovery of our Nation?s mineral resources. The mining industry uses billions of pounds of explosives annually. The majority of blasting occurs in surface mining operations. Blasting results in the fragmentation and often the projection of rocks. Frequently, the rocks are thrown beyond the expected limits. Flyrock and failure to secure the blasting area dominate blasting-related accidents in mining, especially in surface mining. Blasting accidents in the mining industry tend to result in critical injuries or fatalities. Accident reports and information collected from the Mine Safety and Health Administration (MSHA) and other government agencies provide supporting evidence. According to the data collected, blasting-related accidents (in mining) were 11 times more severe than all other types of mining accidents. Blasting accidents are not unique to mining operations - the same situation exists in the construction field. In this paper the authors have compiled a list of the primary causes of flyrock and the failure to secure the blast area. In the next phase of this project, typical blasting scenarios will be reviewed which will highlight the main reasons flyrock and/or lack of blast area security occur. This will alert miners and construction workers to the current problems/hazards associated with blasting and to identify other safety measures to protect personnel.

Jan 1, 2000

By Oliver Bowles

The National Granite Commission at its annual meeting in Norfolk, Va., in January, 1930, passed a resolution requesting the Bureau of Mines to conduct an economic study of the granite industry. In with this request a preliminary review has been made of trends in the production and uses of block granite.. Some unfavorable conditions were thus brought to light, and certain suggestions regarding a more orderly and consistent growth in the industry are herein discussed. The results of the study are, presented in this report for the earnest consideration of. the industry, and comments are invited, not only on this report but as to future work that might be accomplished by the Bureau of Mines. The authors desire to acknowledge many helpful suggestions and comments from Paul M. Tyler of the Bureau of Mines and from Harris F. Sherman, secretary of the National Building Granite Quarries Association. Miss A. T. Coons of the Bureau of Mines rendered valuable assistance through her wide knowledge of granite statistics. The block granite industry has shown little expansion during recent years. While the value of the annual production has grown from about $14,000,000 in 1904 to nearly $25,000,000 in 1928, the increment in value is caused mainly by mounting prices rather than by increased production. Even granite for memorials shows a very small advance in production volume, although the value has increased from about $3,500,060 in 1904 to more than $11,000,000 in 1928, which is the most consistent growth of any branch of the industry. The value of building granite has fallen for a number of years much below the figure for 1904, and in 1928 was very little in advance of the value attained 24 years previously. The use of granite paving blocks and rubble has shown a gradual decline.

Jan 1, 1931

By L. C. IlsLey, H. H. Clark

As part of its investigations of the causes of mine accidents and of the safest and most efficient methods of handling electricity underground, the Bureau of Mines undertook a study of the ignition of mine gases by the filaments of electric incandescent lamps. This bulletin describes the investigation in detail and gives a complete record of the results obtained.

Jan 1, 1913

By B. Peszko

There are many measuring methods of grain sizes. Taking into consideration the fine grained materials, one of the existing techniques is measurement of grain size by the Coulter Counter method. This method is based on the measuring the changes of electrolyte resistance during grains flow through the calibrated diaphragm. This method is relatively simple to apply, significantly precise and the results are given quickly. However, the problem is that the measurements are limited by the size of diaphragm. Because of this situation, measurement of grain sizes by this instrument is possible in range from 10% to 60% of diaphragm diameter. This limitation causes the necessity of re-placing diaphragm in case when the measured grain size distribution concerns the material of large size range. In purpose of determining the total grain size distribution, the synthesis of some partial distributions, given for individual grain fractions (with different diaphragm applied), is required. This is possible to do by calculating the mixture of distribution functions, created from the partial distribution functions. Two materials were selected to research: quartzite and glass, which were comminuted in cylindrical crusher, additionally grinded, screened and then analyzed by Coulter Counter for five grain fractions: 0~125 µm, 0~80 µm, 0~56 µm, 0~40 µm and 0~25 µm. For each fraction, five different partial distributions were given (in case of glass ? four), which are the basis for the creating the joined grain composition. To assure the adequacy of the given distribution function, it is necessary to obtain the possibly best approximation of partial distributions. In the work, both the parametric and non-parametric methods of density approximations of investigated random variable. For each grain fraction the approximations were done by three traditional distribution functions: RRB, GSA and log-norm distribution functions and three methods of non-parametric approximation: Gauss kernel, Epanechnikov kernel and orthogonal Fourier series method. As the criterion of the certain distribution function acceptance, the value of the residual deviation was assumed, given by the formulae:

Jan 1, 2014

By Ali Azizian, Brian Hall

"Driven piles were selected to support the Fraser Heights Bridge bents. Piles were a key component of the top-down construction approach, which was adopted for minimizing potential impacts on an environmentally sensitive wetland. Project requirements mandated verification of pile capacities using dynamic methods. More than 40 Pile Driving Analyzer (PDA) tests were performed. The subsurface conditions were highly variable. On the east side, piles extended through loose sands, soft silts/clays, and two peat layers and were founded in glacial till-like soils at about 45 m depth. However, on the west side, till-like materials were so shallow that it was difficult to drive the piles sufficiently deep to obtain the necessary lateral support. This paper provides an overview of the geotechnical considerations of the bridge design and top-down construction approach, and expands on the presentation of PDA results and how they compared to pile capacity estimation methods and parameters recommended in the applicable design codes.INTRODUCTIONThe Fraser Heights Bridge (FHB) was a component of the Fraser Heights Connector (FHC), a 2 km section of the South Fraser Perimeter Road (SFPR), constructed as part of the Port Mann/Highway 1 (PMH1) Improvement Project. The FHC is located in northeast Surrey BC (Fig. 1).Two major design and construction determinants were: 1) a mandated tight schedule to provide a non-tolled alternative to a new toll bridge; and, 2) an obligation that construction had to occur with minimal impact on the environmentally sensitive wetland the FHB crossed, including limiting the footprint of the permanent and temporary works to less than 45 m2, and prohibiting construction access onto the wetland. Construction equipment was only allowed on the wetland on temporary trestles or on the finished structure. This latter requirement resulted in the bridge being constructed span by span, using a top-down approach."

Jan 1, 2016

By H. Marquis

The present paper consists of a survey of the literature on the problems of abrasion and wear of metals and materials by suspended matter. This problem is a very general one in industry, and is especially notice-able in the operation of cyclones and other types of dust collectors. The problem of abrasive dust in corrosive gas environments, such as commonly encountered in metallurgical industries, is particularly severe. Very little work has been done in the study of this type of abrasive wear, especially at high temperatures. However, a general review is presented here of all the work published on related subjects, such as that involving sand erosion in turbines and water wheels and the effect of temperature on friction wear. Topics in this paper include: blasting wear by sand, quartz, limestone, silicon carbide and other refractory particles; methods of investigation; effects of velocity, temperature and *Canadian Armament Research and Development Establishment, Valcarter, P.Q. angle of attack; correlation between indentation hardness, scratch hard-ness and resistance to abrasion; the effect of protective coatings; resistance of various metals; etc.

Jan 1, 1962

By T. F. Witherbee

IT is proposed to give, first, a description of the works ; second, a report of the first six months of the present blast; and third, such improvements as have been suggested by the practical working. The site selected for this furnace was, at the time of commencing work, October, 1872, entirely covered by the navigable waters of Lake Champlain. A coffer-dam was first built of cribs of round timber filled with stone, forming three sides, while the shore answered for the fourth. Considerable excavating was done with a steam-dredge, a hole being left for it to pass out. The opening was then built up, and the cribbing banked up with blue clay from the bottom of the lake, to render it water-tight and the dam pumped out; the remainder of the excavating being done by hand. All of the foundations, with the exception of the elevator-tower, and fifteen feet of the east side of hot blast, rest on the Potsdam sandstone, which forms the shore line, dipping into the lake at an angle of fifteen degrees. Owing to jogs in the formation, a much greater depth was found necessary than was at first anticipated, the foundation under the stack

Jan 1, 1876

By M. Brennan, A. Majumder

"The mineral processing research community has devoted enormous efforts to the modelling of mineral separators over the last 50 years. While many efforts have been made to use only fundamental physics as a basis for the models, fluid flow patterns in separators are not simple while the motion of particle swarms through fluids is extremely complex.Sluices are the simplest forms of the flowing film concentrators and have been used in the mineral industry since at least the 15th century (Agricola, 1556). Flowing film concentrators, in general, still have widespread applications in the mineral industry and their designs vary according to the specific need.Particle separation in a sluice appears deceptively simple, but the separation mechanism has proven complex and difficult to quantify. Separation in the sluice takes place in a flowing film a few millimetres thick. The particles are suspended by turbulent eddies and motion relative to the fluid takes place in socalled hindered settling mode. The difficulty arises because the presence of the particles influences the flow pattern and when the particles are fully transported by the flow, the flowing slurry may not have the same viscosity as water and does not have the same density. For this reason a universal theory which can explain the behaviour of a suspension in a sluice or any other gravity equipment has still not been developed. Few attempts have been made to analyse the mechanisms involved in the concentrating processes of pinched sluices and Reichert cones.Fluid flow behaviour and slurry transportation characteristics in open channels have, however, been active research topics in the disciplines of fluid mechanics, chemical engineering and civil engineering for many years. As a result, an extensive literature is available, which has led to the development of the model described in this paper.In an effort to test the extent to which fundamental fluid mechanics can provide a prediction of particle separation, a study on a simple parallel-sided sluice has been carried out using glass beads at various particle concentrations and flow rates, and the actual particle separation taking place compared to predictions from modelling.The modelling strategy was divided into two parts; the first was to predict the horizontal slurry flow velocity profile and the second to predict the solid particle concentration over the depth of the flow at different flow conditions. The predictions were then validated with measured data sets. This can easily be done if the slurry flow is split at different fractional flow depths so that the mass flow of solids over different flow heights is measured accurately over a fixed period. Mass flow splits can then be calculated by integrating the product of the predicted slurry velocity profile and the predicted solids concentration profiles from the base of the sluice bed to the slurry free surface."

Jan 1, 2003

By T. F. Witherbee

It is proposed to give, first, a description of the works; second, a report of the first six months of the present blast; and third, such improvements as have been suggested by the practical working. The site selected for this furnace was, at the time of commencing work, October, 1872, entirely covered by the navigable waters of Lake Champlain. A coffer-dam was first built of cribs of round timber filled with stone, forming three sides, while the shore answered for the fourth. Considerable excavating was done with a steam-dredge, a hole being left for it to pass out. The opening was then built up, and the cribbing banked up with blue clay from the bottom of the lake, to render it water-tight and the dam pumped out; the remainder of the excavating being done by hand. All of the foundations, with the exception of the elevator-tower, and fifteen feet of the east side of hot blast, rest on the Potsdam sandstone, which forms the shore line, dipping into the lake at an angle of fifteen degrees. Owing to jogs in the formation, a much greater depth was found necessary than was at first anticipated, the foundation under the stack

By GORDON H. FISHER

During the year 1945, the drilling pace in West Texas increased above that in the year 1944, and represented the highest number of well completions since 2941. The 1680 new wells drilled 8,287,958 ft. of hole for a per well average of 4933 ft. This depth is approximately 30o. ft. deeper than the average for the year 1944. Although the deepest well drilled in West Texas (Phillips Petroleum Company's Ada Price No. 1, in Pecos County) was completed during the year. 1944 to a depth of 15,279 ft. and tested the Ellen-burger horizon, the producing depth record for West Texas was set during the year 1945 with the completion of Amerada Petroleum Corporation's Jones No. I-A, in the Jones Ranch field, Gaines County, which now is producing at 11,422 ft. from the Devonian formation.

Jan 1, 1946

By A. Brown

This report details work performed and results obtained in a study of the water management aspects of oil shale mining and retorting in the Piceance Creek Basin. Three specific sites were investigated, and optimal water management systems for both conventional and in-situ extraction processes were generated. Water-related legal and environmental constraints on development were identified and the water management schemes were developed in compliance with these regulations. Limitations on shale oil production implied by limited water supplies were evaluated. Potential Basin-wide effects of development were evaluated using a computer model, and mitigation strategies were developed. Recommendations for additional investigation and analyses were presented.

Jan 1, 1977