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By P. K. Sen, Mrinal K. Ghose

Tailing slurry is usually abrasive and possesses high viscosity. This paper examines the existing iron ore beneficiation process and focuses on some of the key environmental issues related to the disposal of tailings. It identifies that almost 32% of the iron ore extracted ends up as tailings and they are usually disposed in slurry form in tailing ponds. By the year 2000, 27 Mt of iron ore tailings were generated in India, which has become one of the biggest waste handling problems to the industry. Characteristics of the tailings vary widely. So the physical nature of tailings cannot be considered separately in isolation without considering the mill effluent from the beneficiation plant. In the present investigation, studies were carried out in three iron ore mines in India to evaluate the characteristics of tailings from the beneficiation plant. The tailing samples were collected from different locations during a time period of one year and analyzed. The results will be discussed and the characteristics of the tailings have been evaluated. The disposal system of tailings at the three mines was evaluated. The research on the settling characteristics of tailings indicates that the area provided in the existing tailing ponds in India is much more than that of the experimental results. This paper concludes that sedimentation tests are essential to design appropriate tailings pond with respect to size. In the proposed scheme it is suggested that an additional unit process, i.e. sedimentation tank be added to the process before the disposal of tailings to the tailing pond.

Jan 1, 2003

By Donald J. Ninteman

This Bureau of Mines publication is a literature study of the problem of spontaneous oxidation and combustion of sulfides in underground mines. It summarizes the present-day hazards, process mechanisms, and prevention and control techniques of this growing problem in underground mines. The iron sulfides generally have the greatest tendency to oxidize, particularly pyrrhotite. The presence of moisture and oxygen is essential for the oxidation reaction. Highly fractured sulfides, when found with timber or combustible refuse in slowly circulating air, pose the most serious fire hazard. Quenching with water is effective in quickly dealing with local hot spots, but ventilation at high flaw rates is the most effective and economical means for long-term prevention and control.

Jan 1, 1978

By E. P. Ferrero

Crude oils from fields throughout the world are analyzed by the Bureau of Mines to determine the characteristics of the oils and their contribution to the petroleum resources of the world. Analyses are reported for 169 foreign crude oil samples from 122 oilfields in Africa, Asia, Australia, the Caribbean, Europe, North America, and South America. Tables show the geographic and geo- logic origin of the samples, names of companies that supplied the samples, annual production for the fields, general characteristics and analytical and computed data, hydrocarbon-type data, cumulative production of the larger fields, and references to sources of geological and field development information. The analyses were made by the Bureau of Mines routine method and comparisons may be made with more than 8,000 other such analyses.

Jan 1, 1972

By S. G. Luckey, N. R. Harrison, F. Nadeau, U. Brüx

"The adoption of tailored-rolled or tailor-welded blanks (i.e. TRB/TWB) in the automotive industry has been known to offer great potential for the optimization of weight, function, cost and complexity. Vehicle light weighting can further be achieved by using high strength aluminum alloys like the 7xxx-series. 7xxx-series alloys are capable of delivering specific strengths equal to or greater than high strength steels. However, room temperature formability of this aluminum class is limited, so one approach to forming 7xxx-series alloys is by hot stamping. Hot stamping utilizes an elevated temperature blank and the high pressure stamping contact of the forming die to simultaneously quench and form the sheet. This paper explores the initial feasibility of tailored thickness material for body-in-white applications when processed under hot stamping conditions.INTRODUCTION Steel tailor-rolled blanks (TRB) or tailor-welded blanks (TWB) have been used within the automotive industry as a method of reducing weight, expanding material utilization, and decreasing overall part/assembly cost (Ganeasan et al., 2015; Merklein et al., 2014; Hirt et al., 2005; Kridli et al., 2000). The production of such tailored thickness materials has resulted in over $2.5 billion (2016) in combined industry sales (Mubea, 2018). As automakers begin to adopt the manufacturing practices traditionally reserved for steel such as tailor rolling/welding with greater enthusiasm for vehicle light weighting, there exist an opportunity to expand the material database to extend beyond the traditional aluminum alloys found in current production. High strength aluminum alloys, i.e. 7xxx-series, are ideal for structural automotive applications due to their high specific strength; however, they have limited room temperature formability. Hot stamping, another manufacturing practice used by the steel industry, can be used to form these high strength materials. The combination of tailoring the thickness of a sheet material and hot stamping provides an opportunity for significant weight saving within an existing manufacturing footprint. This paper explores the potential and challenges of this approach when applied to structural body-in-white components. The methods for tailor rolling, tailor welding and hot stamping are described and applied to the production of a 7075 aluminum alloy B-pillar. The results are discussed in terms of feasibility and weight savings."

Jan 1, 2018

By R. E. Heithecker

The separation of enormous quantities of water produced with the oil in some West Texas fields necessitated the use of special equipment other than the regular lease tanks. Several methods were used with varying degrees of success. They include the water-trap, hay tank and gun barrel, gun barrel and settling tank, chemical and electrical-dehydration methods. The water trap which has been used extensively in the Hendricks field, and in some instances has been installed in the Yates field separates the water and. oil under high pressure before tile liquid and gas pass through the flow beam. The first trap was constructed and installed by the Southern Crude Oil Purchasing Co. in July, 1928. By July, 1929, approximately 300 traps were in use. Treating cut oil by running it through a hay tank was done quite extensively in the Roberts-Settles field, Howard and Glasscock Counties, Tex., and later the method was used in the Hendricks field. In July, 1931, there were 37 hay tanks in the Roberts-Settles field, treating the oil from 123 wells. The cut oil frequently was made acceptable to the pipe-line company by running it through the hay tank. In some instances, however, it was necessary to heat the oil, and occasionally both heat and chemicals were used before complete separation of the oil and water was obtained.

Jan 1, 1932

By Luminita Calin

King County (Seattle, WA) is on a monumental task of building the new Brightwater System complete with a new treatment plant, three main conveyance tunnels, a new outfall into Puget Sound and other ancillary works. This paper will describe the first conveyance tunnel, Brightwater East currently under construction by the Joint Venture of Kenny (Sponsor) / Shea / Traylor that is scheduled for completion in early 2010. The project located in Bothell, WA (north of Seattle) is in both King and Snohomish Counties. It was the first of the major tunnel projects that was scheduled by King County for the Brightwater System. The East Contract consists of the following major elements: 14,000 ft of 19'-2' EPBTBM mined tunnel using 16'-8' ID bolted, gasketed precast concrete segments for a primary liner; installing and encasing 14,200 ft each of 48', 66', 27', 84' in diameter steel pipes inside the tunnel along with three runs of fiberoptic cable; 2,430 ft of 72' in diameter microtunnel including three caisson shafts and associated structures; one Intercepting Structure (IS) shell to mine from that is 74 ft deep and 74 ft finished in diameter with 130 ft deep slurry diaphragm walls, tremie slab and final concrete wall lining; one Influent Pump Station shell (IPS) 83 ft deep, twin 77 ft inside diameter cells, with 160 ft deep slurry diaphragm walls, tremie slab, and final lining; two short 12 ft in diameter inter-shaft connector tunnels; one extraction shaft 40 ft deep by 40 ft wide and 140 ft long for connection to the new treatment plant piping.

By José L. M. Clemente, John R. Davie

"Abstract An extensive pre-production static and dynamic pile load testing program was conducted for a coal-fired power plant. The static load testing program included axial compression, uplift (tension), and lateral load tests. Three types of piles were tested: Monotube, closed-end pipe, and step-tapered. The load tests were used to (a) determine pile driveability characteristics for each pile, (b) verify pile load response behavior, and (c) provide data to support the selection of a cost-effective piled-foundation system for the plant. A recent publication (Clemente and Lewis, 2013) describes the compression load testing program, the interpretation of instrumentation measurement results, and pile selection criteria. This manuscript describes site subsurface and groundwater conditions and installation of probe piles for testing, focuses on the uplift and lateral load testing program, and provides a comparative interpretation of the load test results.INTRODUCTIONThe pre-production probe pile load testing program described here was conducted for a 202-megawatt, coal-fired power and steam generating (cogeneration) facility. A schematic layout of the main plant (power block area) is shown in Figure 1, which also includes the locations of clusters of preproduction probe piles and boreholes drilled near these clusters.The load testing program included 24 pre-production probe piles driven throughout the power block area. The probe piles were driven at locations T-1 through T-8, shown in Figure 1. Three types of piles were driven at each location: Monotube pile; closed end, straight shaft pipe pile; and step-tapered pile. At each location, the three piles were driven in a row with the pipe pile at the center, and the center-tocenter spacing between piles was equal to about 1.5 m (> 3.5 pile diameters for the largest pile). No pile cap was used to connect the three piles, and the three piles driven at locations T-1 through T-8 will be referred to as pile clusters. A complete suite of static load testing (compression, tension, and lateral) was performed on each individual pile at Cluster T-2 and on the step-tapered piles only at Cluster T-8, shown in Figure 1.Clemente and Lewis (2013) provide details of the compression load testing program, the interpretation of instrumentation measurement results, and pile selection criteria. This manuscript focuses on the uplift (tension) and lateral load testing program. A brief summary of the site geology and existing subsurface and groundwater conditions in the vicinity of the test pile clusters is presented, with emphasis on T-2 and T-8. Probe pile driving results at T-2 and T-8 are also presented. Descriptions of the static uplift and lateral load test program at T-2 and T-8 are given along with a comparative evaluation of the load test results."

Jan 1, 2014

By Y Xie, L O’Connor, S C. Dominy

Sheeted vein gold deposits are characterised by multiple subparallel veins and often free milling gold. Variability in gold grade and recovery parameters are enhanced by poorly designed sampling and test work protocols. Poor quality samples generally equate to an enhanced nugget effect. A sample can be described as being representative when it results in acceptable levels of bias and precision. Total sampling variability can be quantified by the relative sampling variance, which measures the total empirical sampling variance influenced by the heterogeneity of the lot being sampled under the current sampling / test work protocol. Effort should be made to minimise the relative sampling variance through Theory of Sampling (TOS) and quality assurance / quality control (QA/QC) application. This contribution reports on a case study that exemplifies how high-quality grade and recovery data can be gained from a well-designed and planned drilling, sampling and test work program, followed by bulk sampling. Results across historical resource drilling, geometallurgical drilling, laboratory assay / test work, geometallurgical modelling and a bulk sampling/pilot processing study are reconciled. A whole core, entire-sample test work protocol was used to acquire fit-for-purpose gold grade and recovery data for inclusion into a Pre Feasibility Study reported in accordance with the JORC Code.CITATION:Dominy, S C, O’Connor, L, Xie, Y and Glass, H J, 2017. Geometallurgical sampling protocol validation by bulk sampling in a sheeted vein gold deposit, in Proceedings Eighth World Conference on Sampling and Blending , pp 185–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By R. S. Dean

Boron compounds have been considered for many years as possible additions to iron and steel. A very recent use of boron-steel rods was for the control of neutron intensity in the graphite-uranium pile at the Clinton plutonium plant(130).4/ Norris(129) reports that slags containing boric oxide reduce the ferrous oxide content of steels and thereby the aluminum required for deoxidation. Boron is not considered an alloying element, but minute amounts produce what is often called a "needled" steel. The study of a series of iron-boron alloys by convenient steps, starting with iron containing no boron, indicated that boron was a hardening agent and made the iron very difficult if not impossible to forge. Then came the discovery that very minute traces of boron are quite different from the smallest amount previously thought worthy of study.

Jan 1, 1946

By Lewis Martin

Spokane Research Center personnel are currently conducting research on cable bolts to assess their material and support properties, to provide design criteria for roof control systems under various types of underground mining conditions, and to provide background data for computer models of cable bolt supports. Laboratory studies of cable bolts made of conventional steel cables with Garford bulbs and collars resulted in recommendations on characteristics such as embedment length, hole diameter, cable bolt diameter, and configuration of cables. A completed series of laboratory tests has determined the minimum embedment length of resin required for resin-grouted, cable bolt ground support.

Jan 1, 1996

By Jarret Thomson

An understanding of groundwater flow is essential for many aspects of mining. This is especially true for the process of shaft sinking through the sandstones of the Manitou Falls Group in the Athabasca Basin of northern Saskatchewan. Experience has shown that the hydraulic conductivities of these sandstones can be relatively high, especially in zones containing natural fractures. To develop a better understanding of the inflow potential into a shaft, a laboratory testing program was undertaken to investigate the hydraulic conductivity of fracture core samples from the Manitou Falls Group. This program involved the measurement of hydraulic conductivities under steady-state flow conditions, while cycling the effective confining pressure across a span that is representative of in-situ conditions. The change in fracture aperture was simultaneously recorded at each confining stress level. It was found that existing relationships relating aperture and flow did not accurately capture the behavior of the samples tested. The effects of fracture staining and infilling were also investigated, and were found to have a notable impact on the hydraulic conductivity.

Jun 1, 2012

By Ralph Dawson

The following additions to SLP-4 “ALWAYS AND NEVERS” have been approved by the Board of Governors since the last printing 6/97 and will be included in the next printing soon. They are also included in the Second Printing of the 17th Edition of the ISEE Blasters Handbook. Review them and apply those which might be applicable into your blasting program now.

Jan 1, 2001

By Antonio Fabiano de Oliveira

The aim of the present research work is to study the influence of hard chrome covered skin pass cold rolling rolls using 2D/3D surface topography, i.e. roughness characterization. The common stochastic structure Shot Blast Texturing (SBT) does not meet all requirements related to the production line regards to the finished product. The Hard Chrome layer, applied on these SBT rolls, can improve the sheet surface quality and is of fundamental interest mainly for those steel mills that do not have another alternative to new surface structures such as those that may be provided by the EDT, LT, EBT, etc. methods. The function of the generated surfaces, obtained by these different methods is going to influence the tribological properties during the subsequent forming processes. On the other hand, they can increase the product final cost or require large investments to obtain such surfaces. The results here presented are in accordance with other recently published research work, showing that there is a relationship between these parameters, and that further detailed studies are needed.

Aug 17, 2017

To predict the spontaneous combustion potential of bituminous coals using a simple expression based on an easily acquired coal property. Background Approximately 20% of underground coal mine fires in the United States since 1978 have been attributed to spontaneous combustion. Spontaneous combustion fires in underground mines are most likely to occur in gob area; and are difficult to detect and to extinguish by direct fire fighting methods. Often, sections of the mine or the entire mine must be sealed for long periods, at a great economic loss to the mine operator, mine employees, and the surrounding community. It is conservatively estimated that the cost of scaling a large mine is about $50 million.

Jan 1, 1989

Lihir Gold Mine is situated in a dormant volcanic caldera on a small island off PNG. Not æextinctÆ but dormant. Current ground temperatures are up to 150 degrees Celsius with active geysers in the workings of the mine, pools of boiling ground water adjacent to low-grade dumps and hydrogen sulphide gas emissions. It is a unique mining environment by world standards. This paper will deal with the following issues encountered and managed by the operation:blasting in hot and reactive ground; management of sulphide gas emissions; disposal at sea of all mining waste rock; one dear to all Australian minerÆs hearts û dealing with landowner groups; and unusual human resource issues.

Jan 1, 1999

By J. E. Kogel

Industrial minerals play a central and dual role in the sustainable development (SD) of natural resources. Over the past decade the mining industry has increasingly focused on sustainably extracting and processing industrial minerals. This trend has been driven by higher energy costs, diminishing water resources and sensitivity towards environmental stewardship. Industrial minerals have been used throughout human history as low cost, naturally occurring, materials. Today they are critical components of recycled packaging, energy efficient building materials, light weight paper coatings, and other products critical to the responsible utilization of global resources. As industrial minerals become more widely used in ?green? products, mining companies have established best practices for the sustainable management of industrial minerals mining and processing. These management practices include reducing energy consumption, minimizing water usage, increasing waste recovery through recycling and process optimization, and maximizing the amount of ore extracted per acre of disturbed land. With the commitment to SD principles, quantitative methods for objectively measuring SD performance have become increasingly important. Measuring sustainability impact is a valuable tool for effectively applying SD principles and for making choices that balance sustainable development against other business objectives. SUSTAINABLE DEVELOPMENT AND MINING Sustainable development is a term that has become a common part of our lexicon; however, it has multiple meanings and interpretations leading to a sometimes confusing and contradictory array of definitions. The absence of a single, precise definition reflects the fact that SD is a broad concept or paradigm that offers guiding principles as opposed to a specific set of criteria or regulations enforceable by government or other oversight agencies. While a principle based conceptual approach allows businesses to broadly apply SD practices that are tailored to their specific situation, it has also led the public to sometimes view voluntary corporate SD programs with a degree of skepticism (Walker and Howard 2002). This is particularly true in the mining industry. One reason for this skepticism is that the relationship between SD and mining is misunderstood and to many, sustainably developing non-renewable mineral resources is a contradiction (Rajaram et al. 2005). However, this view takes a very narrow interpretation of the tenets of SD. The second is that mining carries a legacy of poor environmental stewardship that does not accurately reflect current corporate environmental practices Many minerals companies have adopted the Brundtland Comission?s definition of SD (United Nations 1987): ?? development that meets the needs of the present without compromising the ability of future generations to meet their own needs?. This definition is very broad and can be interpreted in a number of ways. It provides a general context for sustainable development and is not intended to provide detailed guidelines addressing specific aspects of sustainable development. To fill this gap the following SD principles were drafted by the international minerals community in 2003 (ICMM 2003): 1. Implement and maintain ethical business practices and sound systems of corporate governance. 2. Integrate sustainable development considerations within the corporate decision-making process. 3. Uphold fundamental human rights and respect cultures, customs and values in dealings with employees and others who are affected by our activities. 4. Implement risk management strategies based on valid data and sound science. 5. Seek continual improvement of our health and safety performance. 6. Seek continual improvement of our environmental performance. 7. Contribute to conservation of biodiversity and integrated approaches to land use planning. 8. Facilitate and encourage responsible product design, use, re-use, recycling and disposal of our products. 9. Contribute to the social, economic and institutional development of the communities in which we operate. 10. Implement effective and transparent engagement, communication and independently verified reporting arrangements with our stakeholders. These guidelines insure that SD concepts are applied equally across the industry while setting a clear performance standard and benchmark against which to evaluate success. By adopting these principles and issuing the Milos Statement (http://www.sdimi.org/milos_decl_October%206_2003.pdf), which provides a more detailed vision for integrating SD into everyday business operations, the minerals industry has embraced SD as a core corporate value. The unifying and holistic approach embodied in SD principles impacts the entire mine to market life cycle and addresses the economic, environmental and social consequences of mining. INDUSTRIAL MINERALS The world economy relies heavily on minerals; they are essential to economic prosperity and the quality of life. Industrial minerals are non-metallic, non-fuel minerals that provide the raw materials for a vast range of products used in most every aspect of daily life. They are mined and processed worldwide and they span the spectrum from relatively low value, high volume commodities (e.g. common clay, crushed stone) that are usually mined locally to high value, low volume specialty materials that are sourced from unique one of a kind deposits (e.g. barite, talc, mica). High volume commodity mining operations are often located near the end use market which, in most cases, means areas of high population density where construction and other urban activities drive demand. In these situations the strict adherence to SD principles is particularly critical as these are highly visible operations that must meet the public?s demand for good corporate citizenship. These operations are similar to chemical or other manufacturing facilities that operate near population centers. In contrast, some mining operations are located in remote but environmentally sensitive regions of the globe where the pressure to mine sustainably is driven by the need to preserve habitats and other

Jan 1, 2009

The ultraviolet spectrum of isopropyl ethylthionocarbamate (the principal constituent of Dow flotation collector Z-200) in water and of Z-200 itself in water was found to have an absorption peak at 242 nanometers(nm). The height of this peak was found to be directly proportional to isopropyl ethylthionocarbamate concentrations up to 15 p.p.m. Z-200 contains about 90 per cent isopropyl ethylthionocarbamate and the heightof the peak was proportionately lower, but obeyed the straight line relationship up to 15 p.p.m. This showed the potential value of spectrophotometric measurements for the determination of Z-200 residuals in flotation liquors.Methyl ethyldithiocarbamate (an impurity in Z-200) increased the peak height slightly, but other impurities in Z-200, xanthates, and most inorganic salts present in flotation liquors do not interfere. However nitrate ion and thiosulphate ion have absorption peaks which overlap the isopropyl ethylthionocarbamate peak.The simplest general method to overcome this effect is to extract the isopropyl ethylthionocarbamate into cyclohexane and to measure the absorbance of the extract.The maximum absorbance of the cydohexane extract was at 247 nm and the peak height at this wavelength was found to be directly proportional to the isopropyl ethylthionocarbamate or Z-200 concentration in the original aqueous solution. An alternative method is to measure the spectrum of the original aqueous solution using the aqueous raffinate from extraction as a reference solution. This gives the spectrum due to isopropyl ethylthionocarbamate alone and measurement of the absorbance at 242 nm gives the concentration in the original aqueous solution. Both methods give the same value for the concentration of isopropyl ethylthionocarbamate in the original solution.

Jan 1, 1969

By Wen Tao Liu, Tong Tian, Fu Sheng Niu, Xiu Man Liang

The level of automation employed in flotation production is relatively low. In an actual concentrator, operators use their judgment to adjust the production state based on the visual characteristics of the flotation froth surface. There are shortcomings, such as strong subjectivity and lagging process operation, that easily cause the waste of manpower and material resources. Machine vision technology is introduced to replace human visualization, achieving a quantitative description of the visual characteristics of the froth surface. The state variable parameters are provided for the identification of the flotation conditions.

By Earle C. Waite

THE Industrial Minerals Division this year held no individual sessions of its own except the business meeting Tuesday afternoon. One session was held jointly with the Society of Economic Geologists, one with the Milling Methods Committee, and two with the Society of Economic Geologists and the Mining Geology Committee. At all of these meetings the attendance was better than usual and the Tuesday afternoon session, with nearly 400 present, probably set a new record for the Division. Joint sessions seem extremely popular when papers of mutual interest are presented. On Monday afternoon, mica was the predominating subject. The North Carolina mines provided most of the information presented, although the discussion brought out similarities with the New England mines. B. C. Burgess particularly stressed the fact that with the existing curtailment of mica from India it is necessary to get the most mica in the shortest time from the mines in this country. He said that the Colonial Mica Corp. hopes to have 1000 mines operating in the near future. This seems a great number, but when one considers that these mines employ from 3 to 28 men, mostly nearer the low figure, the output of each mine is relatively small. Although the price of mica is from six to ten times the prewar price, the yield of 8 to 150 lb. of mica per ton of raw ore does not provide high returns to the producer.

Jan 1, 1943

By N. Mutemeri, T. -L. Field, M. Chuma

The categorization of artisanal and small-scale mining has a significant impact on perception and understanding of the sector, particularly from a livelihood perspective. Several developing countries classify different types of artisanal and small-scale mining based on legal status. Given the nature such activities, the tragedy of the commons theory has been applied to understand the inevitable environmental, economic, sociocultural, safety, and health negative externalities – which are products of informality and illegality. Consequently, formalization is a panacea to sustainability. This article aims to offer a conceptual organization and foundational knowledge for characterization of artisanal and small-scale mining. It seeks to identify existing literature on the subject to avoid replication and acknowledge other scholars. Moreover, the article aims to place the study within the context of existing literature, establishing relationships with other studies and why the research is necessary. This paper pinpoints gaps left from other studies in so far as the characterization of artisanal and small-scale mining is concerned. Thus, reviewing literature abetted in finding similarities and differences on how artisanal and small-scale mining is defined from a scholarly and legal basis. The paper ascertains major claims made by earlier research on this topic, such as environmental impacts, the lack of adequate regulatory framework, and presents querying and probing questions lacking from other studies.

Jul 10, 2024