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By Boden A

A procedure was developed for recovering metal values from copper-smelter fume. The fume is first leached to neutrality with dilute sulphuric acid to obtain a solution of zinc sulphate containing a low level of impurities. The tailings from this leach are treated with hydrochloric acid in two stages, in which tin and zinc are quantitatively leached and recovered as a tin concentrate and a zinc sulphatelzinc chloride solution.About 80 per cent of the lead sulphate is converted into lead chloride, which can be recovered as a pure product.Data on the effect of temperature, acid concentration, aeration, and solid/liquid ratios on the hydrochloric acid leach are presented, and the fate of the most important metals during the recovery process is described. Alternative treatments of the tailings from the neutral sulphuric acid leach were briefly investigated.

Jan 1, 1977

By Lucien Weber

In the Shanghai area, the soil conditions are such that bearing piles have become an essential foundation part of the new highrise buildings. In order to reduce the settlements under the high working loads of about 2300 kN/pile, the Chinese building authorities require the pile tip to penetrate into the compact sand layer, situated at approx. 60-70 m depth. No H-piles have yet been tested under these conditions in Shanghai. This paper describes the driving of 8 H-bearing piles with 4 different shapes and with lengths varying from 45 to 75 m. Dynamic measurements are performed during driving and after a wait time of approx. 40 hours in order to assess the change in bearing capacity in function of time and in order to get an idea about the resistance distribution along the piles by using a stress wave analysis program (CAPWAP). One pile is equipped with channels between the flanges for executing verticality measurements with an inclinometer. However, this test has not yet been performed. One month after driving, two piles of 75 m length are statically loaded both in vertical and in horizontal directions.

Jan 1, 1987

By George A. Lawrence, J. C. McHardy

"Field operating experience with an improved flotation mechanism for handling various flotation applications is covered in this paper. Some aspects of designing flotation machines are also presented. Operating data from extensive testing of commercial size equipment under actual plant operating conditions in the following applications is detailed:1. Copper Flotation2. Fine Coal Flotation3. Base Metal Sulfide FlotationDesign features, design improvements, modifications tested, and overall performance data are reviewed. Some mecl1anical performance data as well as metallurgical performance results are presented. Some comparisons with conventional flotation equipment are reported in this paper.Flotation sizing theories are reviewed and an actual equipment selection ex2.mple is presented. Scale-up criteria used for developing large cells are briefly covered.The paper concludes with a brief review of anticipated future flotation equipment design needs. IntroductionThe mining/milling industry is faced with increasing pressure to cut costs while maintaining product quality and indeed, in some instances, expanding production. For copper, nickel, iron, molybdenum, lead and zinc sulphides, coal, phosphate and some other minerals;, flotation remains the primary method of concentration and recovery of the valuable mineral away from the gangue. Cost reduction in flotation can be broadly focused on two areas:1. Flotation Chemicals2. Flotation Equipment"

Jan 1, 1985

By Tristan Worsey, Nathan Rouse

Florida is one of the major limestone producing states in the United States. The state has unique regional geology and groundwater characteristics that require equally unique mining methods to extract limestone for construction materials. In many regions, aggregates quarries operate by drilling and blasting underwater limestone and then digging the muck with large draglines, while in others, mining operations are able to operate above the water table.

Jan 1, 2019

By G. Tamaro

The World Financial Center is situated on a 60,000 square meter site at Battery Park City at the southern tip of Manhattan Island. The foundations for the buildings and the related infrastructure posed difficult design and construction problems since the site was filled land in the Hudson (North) River. Foundation construction was made difficult by both the geology and the existence of two railroad tunnels which passed under the site. The soils at the site were unsuitable to support construction of heavy structures, and as a result, all of the foundations had to be carried down to bedrock, or the glacial till over rock. Two buildings were supported on piling and special battered caissons which provided lateral support against wind loading. The other two buildings were supported directly on rock, requiring excavation to depths of 19 meters (63 feet) below grade.

Jan 1, 1989

By Sashir Estela De la Cruz

Actualmente la informática como herramienta aplicada al sector minero nacional, es importante -en tanto su empleo adecuado y racional implica alcanzar los objetivos planteados en forma más rápida y con mayor calidad. En este sentido, el presente texto describe el sistema informático que genera soporte al trabajo de modelamiento geológico para la estimación de reservas mineras, de forma que reduce el tiempo y personal empleado en dicha labor. Este sistema se divide en dos partes: estadístico y gráfico y determina la explotación de un prospecto de yacimiento minero.

May 25, 1998

Effective Dry Density Benefication of Coal

Sep 13, 2010

By C. Daly

"The Faculty of Engineering at the University of New South Wales (UNSW) offers a core first-year engineering design and innovation course,ENGG1000, undertaken during the first and second semesters. This course is highly regarded in the sense that it provides an introduction to many concepts and activities that students will experience over the four-year minimum for which they are undergraduates at UNSW. Approximately 1400 students enrol in the semester 1 course across the Faculty, typically 80 of which undertake the Mining Engineering stream. Students in teams of between six and eight design and construct a physical model to represent an aspect of their chosen discipline. For example, in 2013 the mining engineers designed and built a model dragline. This paper concentrates a major aspect of the course - the involvement of team members in group activities and the development of the associated skills of peer assessment and peer review as the course progresses over a period of 12 weeks.The term ‘peer assessment’ in this paper refers to the requirement for students to assess the design components of their peers. This course has a structured requirement in terms of how a successful design is a result of a sound design process rather than a ‘try and see’ approach. Each student must describe in detail the process they undertook to achieve their final design - hence the approach is independent of the discipline and/or project selected.Peer review is a process whereby students review the contribution of their team members to the overall design. This activity encourages team involvement and interaction. The final assessment mark can be moderated by the outcome of this peer review, although it is run twice during the semester. The first ‘run’ is for feedback only during week six and hence no moderation is undertaken.It was found through consultation with students and from questionnaires that both processes are well accepted and highly regarded by students, as they give them a degree of ownership of the assessment process. In addition, the processes provide rapid and relevant feedback on the progress of individual students.Peer review and peer assessment are also considered to be very valuable tools for use in courses in succeeding years. For instance, many of the courses in mining engineering rely heavily on group assessment tasks."

Jan 1, 2014

By C. Pelley, S. Kelebek, G. Kunzel, S. Gregersen, M. Pollanen

A series of small-scale tests was conducted to evaluate the effect of micro-fracture development, imposed by blasting, on the material properties of the rock as well as its resistance to crushing and grinding. The uniaxial compressive strength, tensile strength, Poisson’s ratio, Pwave, S-wave velocity, point load test index, crushing, and grinding work indices were evaluated for samples without any blasting load and for samples which had received a variety of blast loads ranging from a single impact with a lowstrength detonating cord to a combination of impacts at different times and significant impacts with powder factors close to those used in practical blasts. It was shown that the rock mechanics parameters change even at low impacts, suggesting easier crushing of the rock. Damage values appear to be affected by timing as stress wave superposition affects the damage process. Fragmentation is achieved at higher impact levels while work index modification of the fragments is also observed when high powder factors are used, suggesting improvements in grinding.

Jan 1, 2006

By V. A. Marple

At the Twin Cities "lining Research Center (TCMRC) a project is underway to determine how varying the parameters of a coal-cutting process would affect the amount and the size distribution of the generated dust. The cutting parameters being investigated are the cutting speed, depth of cut and shape of the cutting, tool. To accomplish this research ft is necessary to collect and transport the coal dust venerated at the cutting tool to measuring instruments for analysis. The purpose of this contract was to develop and deliver a system of instruments for measuring the size distributions of the generated coal dust. The instruments employed are essentially those developed for particulate air pollution measurements (1, 2). The instrument system covers a particle size range of 0.005 to 20 microns and is capable of performing in situ measurement and presenting data in real time.

Jan 1, 1974

By John W. Mentz

Phase I study efforts addressed: 1) acid mine drainage formation theory; 2) effects of inundation in reducing acid mine drainage formation; 3) summary information on the types of acid abatement technology currently available and the problems inherent in each; 4) analysis of two potential means of partially inundating abandoned segments of active underground mines to reduce acid formation. This subsequent Phase II Draft Final Report addresses all of the above, but concentrates on and defines Item 4. Seal construction techniques were taken through five logical steps as follows: A) Location Analysis; B) Coal Barrier Pillar Analysis: C) Ground Water Analysis; D) Design Considerations: E) Economic Analysis. The design details of both low wall dams and section seals were discussed in a series of segments: a) Case Histories; b) Feasibility Analysis; and c) Design (including representative calculations). Study efforts showed that both concepts are feasible only in certain mines where the geologic-hydrologic physical makeup is suitable to contain a mine pool. Low wall dams in particular were found to have extremely limited applicability as a means of pollution reduction. Section seals, while clearly dependent upon site specific conditions, have a some what broader range of utility and are more effective in pollution reduction. The proven dramatic reduction in acid mine drainage attributable to inundation makes this a concept that must be considered.

Jan 1, 1981

By P. B. Grote

The report is concerned with the issue of the possible transfer of U.S. and other developed country deep ocean mining (DOM) technologies to developing countries. This subject is one of several major issues in current UN Law of the Seas negotiations. As background to the subject, the report provides a detailed critique of the various terms and conditions pertaining to technology transfer in recent negotiating texts. It also provides a description of the relevant DOM technology, sources of innovation, and methods of proprietary protection. Functional requirements for viable technology transfer are developed and used as a basis for the definition of alternative levels of programs and implementation approaches, including required changes in the negotiating text. The consequences of these technology transfer options on the various parties are investigated.

Jan 1, 1978

By Martin Smirlock

A novel instrumentation system has been developed which enables simple, quick, and accurate measurement of vehicular dynamics within low speed ranges. The system, consisting of a microwave transceiver and microprocessor data acquisition and reduction system, measures the deceleration dynamics of low-speed mining and construction equipment. It makes the basic measurement, calculates key parameters such as average deceleration, initial velocity, stopping distance, and brake system delay time, and produces autoscaled graphs of velocity, acceleration, and displacement versus time.

Jan 1, 1981

By E. E. Ungar

Criteria applicable to noise in coal cleaning plants are presented, and the generally applicable noise control principles and approaches are discussed. The operating characteristics and equipment of coal cleaning plants are described. Considerations entering in the selection and design of noise control means are delineated, and specific means for equipment noise reduction are described. The limited utility of acoustically absorptive materials in plant spaces is indicated, administrative means for reducing worker noise exposure are pointed out, and ear-protective devices are described briefly. The reduction of plant noise reaching nearby communities is discussed. Programs leading to quieter machines an coal cleaning plants are suggested.

Jan 1, 1974

By Y. L. Su

Deterministic and stochastic simulation were combined to develop a computer model of an open pit mining system using bucket wheel excavators and related materials handling equipment. The model is closed and dynamic in the sense that information is fed back to control activities at various levels and reservoirs. The results of interaction between unit operations in one time interval determines overall system behavior for the next interval. Equipment performance curves and system profile characteristics rather than time studies are applied to determine the operation of each activity at any time period. For that part of system where performance is dictated by a random variable~ subjective probabilities are employed. Two stages of research were considered to formulate this model. Stage one involved the formulation of equipment sub-assemblies for the sequence of equipment moves along with related assignments and routines for information retrieval. The second stage of research combined all sub-assemblies into an integrated open pit mining simulator. The model is not tailored for any specific open pit operation but is readily adaptable to any system of surface mining including operations having a high degree of complexity. Questions answered by the model include: 1) system design and selection of equipment for a new mining operation; 2) analysis of existing operations for possible changes, additions or general

Jan 1, 1971

By M. Shamsuddin

Information on total estimated uranium reserves and domestic requirements have been collected, A survey has been made on the possibilities of recovery of uranium from low grade and complex ore deposits, e.g., marine phosphorites, shales, coal, sea water, etc. In order to assess the potential for uranium recovery from uraniferous phosphorites, available thermodynamic data of uranium minerals, compounds and aqueous species have been collected. The existence of uranium complexes with chloride, fluoride, carbonate, phosphate, sulfate, etc., in ground waters have been evaluated at different pH's. There seems a great need to study the relative stability of these complexes in order to judge the applicability of solution mining technology for selective leaching of uranium from phosphorites. A typical flow-sheet demonstrating recovery of uranium from wet-process phosphoric acid has been included in this report. Some essential features of the economics of uranium recovery from uraniferous phosphorites have been briefly considered and recommendation have been made for further studies.

Jan 1, 1980

By G. P. Houston

This is the final, report submitted for the Contract No. H0220002 with the U. S. Bureau of Mines for the design and development of a Permissible Automatic Data Acquisition System (PADAS) to measure and record roof stresses in underground mines Basically the PADAS is a portable, battery powered, 24-channel data acquisition system designed for safe unattended operation of up to 30 days duration in explosive environments. The unit will accommodate twenty-four pressure transducers or eight borehole deformation gages (or any combination) at distances up to 300 feet from the PADAS to measure pressures up to 10, 000 psig. All 24 channels as a selected group are scanned sequentially at one of several selectable rates.

Jan 1, 1973

By W. Biermann

All industrial processes are economically driven, resulting in the ever increasing need for process optimization in order to stay competitive and profitable. Numerous models has been published depicting the optimization of the raw material usage in an arc furnace, as well as the thermal and electrical efficiency; however, to obtain a holistic view of the cost-effectiveness of the process one needs to expand the model to include the cost of all the operational variables. This project therefore aimed to not only include the raw material feeds and power consumption as input variables, but also the labour, maintenance, and environmental costs to generate an all-inclusive financial balance. In the end, the model was able to mathematically optimize the ferrochrome (FeCr) production process through evaluating the effect of a specified combination of input parameters. It could therefore be used as a tool to aid in managerial decision-making; to appraise and correspondingly adjust certain operational variables in order to achieve a maximum return on investment. This paper fully describes the reasoning behind the choice of the essential model components, the assumptions made during the models development, the calculation approach, as well as the advantages, limitations, possible applications, and areas for expansion of the final model. Through running simulations with plant data, it was found that the accuracy of final model remained fairly constant when applied to stable furnace conditions, but was met with a number of limitations when applied to more complex situations. These limitations could, however, be overcome through further development and expansion of the existing model to include a larger number of process variables.

Jan 1, 2012

By James J. Anderson

In this talk I will report on an effort to reassess the risk of pile driving to juvenile salmonids migrating through Puget Sound. The study was motivated by the concern of the construction industry that provisions restricting pile driving during the spring migration is resulting in an unbalanced burden to the industry. In simple terms the industry wants to know if some construction can be conducted in the spring without harming the juvenile fish. Fisheries agencies have agreed to reconsider their regulations in the context of additional studies. So, in this talk I will present some thoughts on risk assessment in general and the results of our study to assess the impact of pile driving on Snohomish River juvenile pink and chum salmon that migrate through the Navy Homeport construction site at Everett. The research, which is being carried out by the Fisheries Research Institute at the University of Washington, was planned and is supported in a joint effort including: the Washington Department Fisheries, National Marine Fisheries Services, U.S. Fish and Wildlife Service; General, Manson, and Hurlen construction companies, the Department of Transportation and a number of Puget Sound ports authorities. I will first briefly discuss the early life history of the juvenile salmon the regulations are designed to protect Second, I will outline the legal criteria required for risk regulation and some specific thoughts on how a reassessment of pile driving risk might be approached. With this basis I will report on our research and how it can be applied to a new risk assessment.

Jan 1, 1990

By Prasenjit Basu

Drilled displacement piles are being increasingly used as foundation elements, particularly in projects requiring fast construction. Different types of drilled displacement (DD) piles are available in practice. DD piles are classified according to the drilling tool design and installation method. The capacity of a DD pile, depending on its type, is between the capacities of geometrically similar nondisplacement and full-displacement piles installed in the same soil profile. This paper provides an overview of the different types of DD piles and their installation techniques and describes three design methods used in practice. It also compares DD pile capacities obtained with these design methods for two different sites.

Jan 1, 2010