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By E. P. Evert

Profitable marketing of most minerals is dependent upon the total delivered cost to the user. Transportation costs are often greater than the value of the mineral f.o.b. the mine or processing facility. In some cases, transportation costs are three to five times the mineral cost. For many years, transportation costs were controlled by a complex system involving the transportation companies and supervised by regulatory agencies. This paper will deal with the effects of deregulation on rail costs and outline the major changes in transportation economics.

Jan 1, 1985

By Z. R. Llanos

The petroleum refining industry makes extensive use of catalysts for the conversion of crude oils into more usable products such as gasoline, fuel oil and gas, aromatics, and others. Catalysts used for hydraprocessing contain cobalt-molybdenum or nickel -molybdenum, although there are catalysts that also contain tungsten. During hydroprocessing, nickel and vanadium are deposited on the catalysts, eventually rendering them inactive. The refiners are then confronted with the problem of disposing the spent catalysts. In the past, landfilling was a common method of disposal and it is still practiced in some countries. Other refiners prefer to stockpile the spent catalysts at the refineries until the price of metals warrants their sale to metal reclaimers. This practice, however, poses environmental problems to the refineries for storage and disposal of spent catalysts. Other types of catalysts are amenable to regeneration. The purpose of this paper is to focus attention on the recovery of nickel, cobalt, molybdenum, vanadium, and alumina from spent hydroprocessing catalysts by Gulf Chemical and Metallurgical Corporation and to review the use of sodium hydroxide and sodium carbonate for pressure leaching of spent catalysts.

Jan 1, 1986

By M. P. Corriveau

This is the case history of how two nearby plants in Southwest Virginia solved their water clarification problems. While the solutions should not be considered applicable industry-wide, the methods used in arriving at the answers deserve consideration. When Clinchfield's Moss No. 2 Preparation Plant, the first ever built in Tiller Seam coal, was started in the fall of 1956, the clays in the raw coal soon posed a flocculation problem, Laboratory sedimentation tests were initiated; and as a result, lime was adopted as the flocculant for the clays, With lime, a pH of 11.2 was required. As the plant tonnage increased, it became evident that the amount of coal fines produced in the mining and preparation was greater than had been estimated and that the 90-foot thickener was inadequate in providing sufficient settling time to effect a clarified overflow for reuse. Testing showed that Separan 26105 (NP10)1/, when used with lime, was the most satisfactory coal flocculant available,

Jan 1, 1960

By T. W. Martin

The use of conveyors in large, open pit mines and their drawbacks are discussed. Technological developments such as long distance conveyors capable of handling large rocks are explored. The development and testing by the Bureau of Mines of a prototype crib and cable conveyor for handling large rocks are discussed, and possible modifications of the concept for a production model are examined.

Jan 1, 1984

By D. R. Willmer, E. J. Haas

"DISCLAIMER The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health. Reference to specific brand names does not imply endorsement by the National Institute for Occupational Safety and Health. ABSTRACT This study analyzed the publicly available health and safety policies of 26 mining companies to determine the quantity of health and safety (H&S) practices that mining companies encourage in relation to the Plan-Do-Check-Act cycle. A thematic content analysis of the policies identified elements and practices within the text. On average, companies communicated information on about 7 elements (range 1–14, standard deviation = 3.49) and discussed 15 practices (range 2–34, standard deviation = 9.13). The elements in which companies highlighted the most practices were risk management, emergency management, leadership development, and occupational health. A discussion of the policy trends shows areas that mine sites can improve upon within their Plan-Do-Check-Act cycle, in addition to encouraging the use of both leading and lagging indicators to manage health and safety performance. INTRODUCTION Mining companies and their employees are expected to identify and manage risks at their worksites to ensure the health and safety (H&S) of everyone at the site. The primary mechanism in place to control these risks is a company’s health and safety management system (HSMS) (Boyle, 2012). Broadly, an HSMS is a set of standard, interrelated, and interacting elements used to promote and achieve occupational H&S goals (ANSI/AIHA Z-10, 2012; BS OHSAS 18001, 2007). The practices conveyed within an HSMS are expected to minimize incidents, injuries, illnesses, and even save worker lives (Alsop and LeCouteur, 1999; Arocena and Núñez, 2010). In the United States, both the Occupational Safety and Health Administration (OSHA) and Mine Safety and Health Administration (MSHA) regulate and encourage aspects of an HSMS (US Federal Register, 2011, 2010). Many HSMS documents (i.e., Chemical Industries Association, 1995; Health and Safety Executive [HSE], 1995; International Labour Office [ILO], 2001) attribute the source of their basic management system to Deming’s Plan-Do-Check-Act (PDCA) model of continuous quality improvement and organize their practices within this cycle (Johnson, 2002). The PDCA cycle is a well-adopted approach in health and safety management and promotes continuous learning and adaptability (Robson et al., 2007)."

Jan 1, 2018

By Charles Bruce

Three years ago, at a reception given during the Steel Institute meeting in New York, I heard the remark, "A new formula must be found for foreign investment." This was immediately following the takeover of U. S. Steel's Matilde operation in Bolivia. Recently, at the World Mining Congress in Lima, Peru, the subject of foreign investment was still a lively topic of conversation. The nationalization of the copper mines in Chile and recent trends in the "Third World" have made all but a few extremely wary of investment anywhere other than in the ?stable? countries. Now, the fallibility of this philosophy has been demonstrated in such "stable" countries as Canada, Australia, and Ireland. Yet, nationalization is not new to us. The events in Chile were classified as disastrous to the affected companies, but so were the effects of nationalization to the majors in Bolivia in 1952. Mexicanization of the mining industry in Mexico was considered impractical by many. Now, those who accepted it are finding it to be workable.

Jan 1, 1975

By A. S. Henderson

Eastern Mesabi taconite is one of the hardest rocks known, but fortunately it shows little tendency to pack in the crushers, when the minus 5/16 inch material is removed. The crushing circuit is essentially as shown in the Engineering and Mining Journal article, "Reserve's New Taconite Project", dated December, 1956 except that the grizzly screen between the two stages of gyratory crushing has been eliminated. The Reserve operating staffs aim is to utilize the crushing equipment in such a manner that the maximum tonnage of taconite can be crushed to the required size at a minimum cost. As is readily apparent, the primary consideration is to produce a desired size product, with the other operating factors to be balanced, thus achieving the best setting for each crusher. Much effort has been expended toward the development of a satisfactory sized material for feeding the rod mills. The characteristics of this feed must allow the following situations to be handled by the existing equipment: 1. The material being fed to the rod mill must be such that it can be fed into the unit with the proper quantity of water to maintain the correct density within the mill. 2. The rod mill must produce a product from this feed which can be handled without difficulty by the magnetic cobbing and ball mill circuit. 3. The incidental tramp must not exceed that quantity which can be handled easily after the rod mill and after the ball mills.

Jan 1, 1959

By M. F. Corcoran

Rapid advances have been made in the past few years in the application of automatic controls and instrumentation to iron ore pelletizing plants. Present practice in applying instrumentation and control to the Grate-Kiln system of iron ore pelletizing is described. Major control points and loops are tabulated. Future trends in the application of digital control including computer data logging systems are described.

Jan 1, 1965

By B. Arvidson

Computer-controlled machine sorting may, if properly applied, have a dramatic effect on overall economics of a mine operation. Radiometric and photometric sorters have been used for many years and new developments will be reported, such as a sorter for fine particles and a conductivity/magnetic sorter. Application examples with emphasis on precious metals will be given. Economics for some of the projects will be reviewed and discussed. Sorting underground is shown to be particularly attractive, but machine sorting would be profitable in most cases based on savings in transportation and milling/beneficiation costs only.

Jan 1, 1987

By Keith S. Olsen

Any discussion of barite mining is virtually impossible without considering, almost in the same breath, the many other variables, such as beneficiation, transportation, infrastructure and location that impact the economics of a particular barite orebody. My comments will be limited to just the mining aspects of barite orebodies and these observations must be considered in proper context with all other parameters affecting exploitation of a barite property prior to final decision on economic feasibility. In many instances low-cost mining situations are more than offset by high-cost beneficiation requirements. Likewise, there are cases of relatively high-cost mining associated with no or low-cost beneficiation requirements thus permitting economic exploitation. Barite orebodies and occurrences are almost as varied as the number of occurrences. As in most mining situations, the design of a mine plan and implementation of a proper exploitation program must be approached on a case by case basis. Proper and sufficient geologic control of a barite orebody must precede the development of a mine plan. Generally speaking, barite orebodies can and, at many times, do "strange" things; pinch with depth; almost never increase in size with depth, overturn, fault-off, change grade, etc. Due to the extreme variable nature of most barite orebodies, a mine plan and its implementation must be as flexible as possible. The ability to quickly adapt to variable conditions will greatly enhance the economics within a particular barite mining environment.

Jan 1, 1980

By G. X. Wang

The nonliving dried water hyacinth (E. crassipes (Mart.) Solms) roots were investigated for biosorption of cadmium and lead and other heavy metal ions in aqueous solutions. Dried water hyacinth roots, when suspended in solution, strongly and rapidly sorb several different metal ions. Factors such as reaction time, pH, initial concentration of metal ions, presence of other metal ions and biomass concentration were investigated. Metal ions, including Cd2+ and Pb2+, were bound to the root in a very pH-dependent manner, with the binding increasing after about pH 3. High levels of removal were obtained. The adsorption was shown to follow the generalized Langmuir adsorption equation. The relative affinity of the roots for lead is greater than for cadmium. The maximum sorptions of the roots were about 33 and 86 mg/g for cadmium and lead, respectively. Only 15-20 minutes were required for the process of uptake onto the biomass to occur. The batch sorption kinetics of the uptake of cadmium and lead can be described by an apparent first-order reversible reaction model. The roots could be regenerated after the metal ions were stripped. A solution of CaCl2 in acidic medium appeared to be the best eluant for desorbing the sequestered Cd and Pb completely at pH 3. The kinetics of the metal stripping process was quite rapid. Successful desorption of Cd and Pb from the biomass by acidic CaCl2 solutions revealed that the metal uptake phenomenon is reversible, implying physical sorption of Cd and Pb.

Jan 1, 1997

By Harry E. Holzschuh

The two Agrico Chemical Company self unloading Phosphate Rock barges put into service in 1976 operate at over their design carrying capacity. Each barge now carries 26,000 short ton instead of the planned 25,000 short ton at 32 foot of draft. They are in service between Agrico's Tampa, Florida Terminal and the Donaldsonville, Louisiana Fertilizer Complex, moving a total of 2,500,000 short tons each year. This was the first use of the Parascrew design for a marine application. The barges, with their 3,000 STPH unloading and matching loading rate is the vital link in this total transportation and handling system. Rock is moved from the Pierce, Florida Mines through the Tampa Big Bend Terminal, across the Gulf of Mexico, and up the Mississippi to the Agrico Faustina Phosphoric Acid Plant 30 miles below Bacon Rouge, Louisiana. The trip from the terminal to the plant is 600 miles and the turnaround time is just about six days. Seven years operating experience has proved that the system works. Fittingly, the two barges are named the "Faustina" and the "Pierce". They have a beam of 85-feet and are 495 feet long. folded depth is 43 feet, with a ballasted light draft of 19 feet and a typical loaded draft of 32 feet. There are four separated holds with the machinery room located forward of 101 hold. Each hold is 51 feet wide at the coamings with an 18 foot straight section on the side, and a 24 foot long, 600 slope sheet for a 23 foot clear reclaim width at the bottom. The Parascrew in each of the holds is 37 feet long between the bearings and is supported on a 14 inch diameter hollow shaft. The screw pitch varies and the diameter of the flights step up from l'-9" diameter to 2'-6" diameter on the discharge end. By sloping the centerline, a minimum four inch bottom clearance is maintained across the hold. Some bending of the tube does take place.

Jan 1, 1983

By J. G. Davis

Continental Oil Company has spent over four years of research on the fundamentals of potash solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multi-well mining systems were studied in the field work. The current paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test. The potential economic value of solution mining has been recognized for many years, and applicable United States patents date back into the past century. Principal advantages of the process over conventional mining include (1) the use of drilled holes and solution techniques in- stead of excavated shafts and caverns and (2) the ability to mine both land and marine deposits through any type of overburden geology and below conventional mining depths.

Jan 1, 1969

By Jr. Koch

Since 1882, world zinc production has increased. In contrast, United States zinc production rose until about 1915, but since then has remained nearly constant, with a slight tendency to decrease. Production from the Tri-State district, the largest early source of zinc in the United States, has gone down steadily; this decline has been balanced by a growth in the rate of other districts. These changes in United States production are due to economic, not geological, factors. Recent exploration has located large mineable ore bodies; additional deposits will undoubtedly be found in the strata-bound carbonate rock and volcanogenic environments. A statistical analysis of the exploration effort in the Middle Tennessee district indicates that new discoveries can be expected there. Thus, the United States is in an early stage of the production cycle for zinc. Of major mining districts in the United States, only the Tri-State is exhausted under current economic conditions; large zinc resources of low-grade material, which would repay mining at higher prices or improved technology, are known to exist in that district.

Jan 1, 1980

By R. E. McIvor, Brian Cornish, J. A. Finch, Yue Tan, Claude Gagnon

Fred C. Bond is recognized throughout the mineral processing world as the father of comminution equipment applied science and engineering. The Bond Work Index became a universal standard, and is the most widely used measurement tool for comminution energy consumption. This biography is the story of his lifetime of study, work experiences, experimentation, analyses and findings. His numerous published writings are reviewed. His legacy is one of comminution process engineering that will be used in perpetuity.

Feb 1, 2024

By Z. Xu, Z. Li

Colloidal interactions play a critical role in mineral processing, including grinding, physical separation (particularly flotation), dewatering, and tailings management. Despite great energy input in comminution to liberate valuables from gangues, heterocoagulation between valuables and gangues would prevent the separation of valuables from gangues. On the other hand, selective coagulation/flocculation to increase the size of desired fine particles could enhance physical separation and dewatering, while dispersion is needed for fine grinding. To control the state of colloidal dispersions by creating favorable conditions, it is of paramount importance to study colloidal interactions in a relevant system and understand underlying mechanisms. This review summarizes recent advances in developing the-state-of-the-art techniques and novel methods of measuring colloidal forces, including atomic force microscope, surface force apparatus, zeta potential distribution measurement, quartz crystal microbalance with dissipation, and our recently developed integrated dynamic force apparatus. The basic principle of each technique was introduced first, followed by a summary of critical information derived for the relevant mineral processing systems. Finally, the pros and cons of each technique were discussed to emphasize the use of complementary techniques that assist in solving fundamental problems in mineral processing.

By R. O. Vernon

The Florida Peninsula has existed as a part of a much broader plateau, since at least the Early Cretaceous. This plateau, the Floridan Plateau, now consists of the present peninsula and a broad submerged shelf of equivalent size extending the length of the state and out into the Gulf of Mexico. Florida Peninsula was separated from the mainland United States by a negative area called the Suwannee Straits. To the south of this feature existed an environment similar to today?s Bahamo Banks where very pure calcium and magnesium carbonates with associated evaporites were deposited. Thus the Eocene and Oligocene contain little or no quartz sand or clay minerals except in the Panhandle west of the Suwannee Straits where some clastics were contributed by rivers from the north.

Jan 1, 1966

By Robert K. Jones

Filter media can be defined as that material which effects the removal of finely divided solids from a fluid. Thus the removal of dust from air or turbidity from water, for example, can be the result of passing the fluid through a properly supported filter media. Since filtration in one form or another has been practiced since pre¬historic times filter media have been made from an extremely wide variety of materials. Vegetable and synthetic fibers (used loose, or formed into papers, felts or cloth) sand, ground coal, diatomite, perlite, wire cloth, porous metal, and bonded aluminum oxide are among the more important materials used today.

Jan 1, 1961

By K. Saberyan

A technique is described for the solvent extraction of zirconium. In this method, zirconium has been extracted quantitatively from 0.005 M sodium salicylate solution at pH 2.5 - 3 using 0.01 M triphenylphosphine oxide dissolved in toluene as an extractant. Zirconium has also been recovered quantitatively from 0.2 M potassium thiocyanate solution, but extractions in nitric and hydrochloric acids (as media) were negligible. The resulting extracted metal ion has been stripped with sulfuric acid (0.5 M) and determined with inductively coupled plasma atomic emission spectrometry. This method has been applied successfully to achieve 95% recovery of zirconium from zircon concentrate.

Jan 1, 2010

By Ross W. Whipple

Applying geophysical techniques in potential geothermal areas has received: little attention in the United States, though it is widely used and accepted in New Zealand and Italy. In those countries it has been demonstrated that geophysical surveys can be useful in locating new geothermal areas and in directing test drilling programs. Geophysical studies in a thermal region can provide structural information and, if conditions are right directly; locate subsurface hot waters. They can give indications of sub-alluvial rock types and of the thickness of alluvial cover. In certain cases they can be used to estimate the power potential of a hydrothermal system.

Jan 1, 1963