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By M. D. Flavel

Testing methods are described to help in decisions of selecting the most viable comminution circuits. The authors present a comparison evaluation based on numerous studies to help make initial choices for feasibility evaluations. An update summary of completed Bond grindability and Abrasion Index testwork at Allis-Chalmers Process Research Test Center for all materials is included. "What is the best circuit to comminute primary crusher product to make beneficiation feed?" This frequently asked question has the implication that there is one circuit which is universally the right circuit. The answer has been sought ever since it has been necessary to break rock to liberate entrapped mineral values. With every new contribution to the art and the science of comminution, the scope of the discussions broaden. It is not even possible to define what the abstract term best means.

Jan 1, 1981

By H. Ikeda

INTRODUCTION [Slide 1] The Role of the MMAJ Ladies & Gentlemen, it is a pleasure for me to be able to make a speech at this SME annual meeting, representing the Metal Mining Agency of Japan. [Slide 2] Today’s Topics In my presentation today, I would like to divide my topics into four parts. First of all, I would like to describe the current situation of Japanese non-ferrous metal mining and mineral processing industries in Japan. Secondly, the supply and demand of non-ferrous metals in Japan. Thirdly, I would like to spare some minutes on the overview of overseas development by Japanese mining companies. Finally, since some people may not be sure what the Metal Mining Agency is or what this Agency, I would like to briefly introduce the Metal Mining Agency of Japan.

Jan 1, 2001

By Orris C. Herfindahl

Every few years we are treated to a battle over trade policy when the Reciprocal Trade Agreements Act comes up for consideration. In 1962 it is especially appropriate to consider the problem of mineral import -policy and the closely related problem of general import policy, for this year's struggle is different from those of the past in two ways. First, proposals have been made which are a substantial departure from past trade agreements legislation, and second, the formation and growth of the Europe Economic is Community may have an important bearing on the kind of legislation that is adopted. But this anticipates what is to come later. My task is to examine the problem of mineral import policy, although we shall find soon enough that general trade policy must be considered in order to get an indication of what is in store for minerals.

Jan 1, 1962

By Luc Morin

What you don't know won't hurt you! This attitude can get you into trouble when considering your process! When trying to extract the most and the best possible performance from a mineral processing circuit this should be reworded to say: What you don't know about your process will hurt your profits! Today, with the popularity of joint ventures, custom milling contracts and process audits by specialists, not knowing is a formula for trouble! Good Sampling Systems are no longer considered a luxury' Not too long ago the practice of grab sampling was considered acceptable and became the norm. Today, it is rare to hear metallurgists say, "All I need is a trend not a good representative sample. so I'll just grab a sample every few hours." Buyers and sellers of quality products have found that grab sampling leads to poor partnerships'

Jan 1, 1999

By Russell W. Hunt

The cave man of ages past took his wife-and family from the cave pointing to a fire he had built and beating on his breast said, "Look what I have done". Today man is taking his family back to a cave saying, "Come enter in because of what I have done". At the close of World War II Germany said if they had gone underground one year earlier with more of their operations, the war could have lasted four years longer with perhaps much of Britain devastated. The protection of the home front no longer rests with the soldier in actual combat. The battle will be won at home with the most careful kind of protection against missiles. After Nagasaki-Hiroshima Sir Winston Churchill said in substance "Up to now the Almighty has mercifully withheld from man the knowledge of these terrible weapons of destruction."

Jan 1, 1959

By J. Astier

The idea of using only one strand for both sintering and cooling of the sinter is not new. In 1952, in the U.S.A. a sintering plant was built at Benson Mine (Star Lake, N.Y.), including : - 68 m2 or 735 sqft (8 wind boxes) for sintering, - 22 m2 or 237 sqft (3 wind boxes) for cooling. In the USSR, a large number of machines have been built allowing for cooling of the sinter on the strand, especially the 4 m (about 13 ft) machines, with : 252 m2 sintering grate area 60 m2 cooling grate area 312 m2 total grate area. However, such ventures did not prove very successful, and the IRSID embarked many years ago on a research program to discover : - what are the problems associated with cooling on a sintering strand ; - what are the possible solutions for industrial plants.

Jan 1, 1974

By Scott G. Britton

In the real world of coal mining, the bottom line for almost every support project decision is economic (i.e., what is it going to cost?). Up to this point, I have discussed the methods to improve the performance of typical support projects by better installation, materials, and techniques, thus lowering the impact of the bottom line cost. In this chapter, 1 shall explore what costs are relevant in mining construction, and how these costs are developed. The chapter centers around two major discussions: (I) developing cost accounting techniques, and (2) cost-estimating procedures for support construction. Each focuses on the fundamentals of practical cost considerations necessary for decisions on construction projects underground. Since cost accounting, economics, and investment planning are all subjects which warrant complete discussions on their own, this chapter will focus on distilling the important concepts required by a planning engineer into an easily understandable presentation.

Jan 1, 1983

By Bill Elverman

Randy and Kenny Robison have visited every coal mine that would let them in the door, to survey the best mining practices. The brothers have spent nearly their entire lives working in coal operations. The Robison’s started out on lube and grease trucks and worked their way up to respected industry leaders in Alabama. The Robisons have owned MS&R since 1989. Since then, they have created a niche for themselves in providing coal for Alabama’s metallurgical coal market. A great deal of the knowledge the Robisons have amassed throughout the years has come from observing — taking note of what works and what does not. In early spring 2004, they commissioned a Komatsu America PC3000 Super Shovel. Outfitted with a backhoe attachment and a 16-m3 (21-cu yd) bucket, MS&R’s PC3000 is currently one of the largest mining excavators working in Alabama.

Jan 1, 2005

By D. Mudd, G. Robertson

"Ask an average non-industry person on the street “What is coal? What is coal mining? What is a coal miner?” The most common answers are coal is something Santa puts in your stocking for being naughty, coal mining is destroying the earth causing global warming, and a coal miner is a person that uses a pick and shovel to dig coal out of the earth. As farfetched as these answers seem, unfortunately this is the opinion of many Americans. Realizing the lack of educational opportunity regarding coal and coal mining, a first-of-its-kind grassroots coal education program known as CEDAR (Coal Education Development and Resource) was created. What started from a general conversation at the December 1992 North Carolina Coal Institute (NCCI) Winter Meeting at the Mid Pines Club in Southern Pines, North Carolina led to the creation, and later expansion of, CEDAR. NCCI President, Gene McBurney, challenged John Justice, NCCI Board Member from east Kentucky, to come up with an idea of how to improve the image of the coal industry, pledging $5,000 from the NCCI as seed money to assist in the development of any such program. John then met with the leaders of Coal Operators and Associates, Inc., (COA) in Pikeville, KY where they agreed to match the NCCI commitment, as well as to assist in the program’s development. After further meetings with representatives from industry, business, and the local school system, CEDAR, Inc. (of east KY) was born. The first year of implementation, the program offered coal education programs to public and private schools in one county in east Kentucky. Although it started in the coalfields of eastern Kentucky, it certainly did not end there. After an amazingly successful first year of the program, it didn’t take long for industry leaders in the western Kentucky coal-fields to learn about, and take note of this new, unique, and exciting program that provided opportunities for teachers and students to learn, “the rest of the story” about the coal industry. Through the joint efforts of Costain Coal, and the Western Kentucky Coal Association, CEDAR of West Kentucky, Inc. was formed in 1994, and has operated since that time, except for the two year period from 2004-2006. The program restarted in 2006 under the name of CEDAR West, Inc. and continues to be offered in six western Kentucky counties."

Jan 1, 2015

By David Hurth

JOHN HAMRIC: Our next topic leader is David Huth, superintendent of sulfuric power generation, DAP, and shipping for IMC-Agrico, Nichols Plant, Mulberry, Florida. With a title like that it's no wonder he believes in empowerment. His topic today is "The Triumphs and Pitfalls of Using Empowerment Techniques." DAVID HUTH: Empowerment and its benefits are a desirable alternative to the traditional management structure. The difference between the two is the amount of decision- making authority and responsibility given to individuals by a supervisor. Just what is empowerment and how does it work? Empowerment is relinquishing to individuals the authority and responsibility to make daily decisions. Can everyone be empowered? What if they make a wrong decision? Will I empower myself out of a job? These are questions that all managers have when they hear the word empowerment. In today's fast-paced and high-pressure business environment, the old way of managing people must be replaced with a new approach. No longer can we, as managers, make all the decisions. The increased work loads due to downsizing, consolidation, and synergies have stretched us too thin. What about our employees? How can we motivate them into the high-performance teams that our companies are demanding? What possibly could satisfy both these issues? The solution to these problems can be solved with the power of employee empowerment. Employee empowerment will not only lessen the load on managers but will build teamwork, motivation, and pride into the employees who work for the managers who use it. American business was rudely awakened in the early 1980s when the Japanese companies not only caught up to American companies but literally flew by them. America was fat, dumb, and happy after World War II. Why wouldn't they be? They had all the factories. Everyone else had to rebuild. So for 40 years American business lounged in the limelight of very little true competition. But times change. Unfortunately, American business did not. Now the cry to perform in the new global economy has come down from the corporate boardrooms. Down through the ranks it has been felt. Guess who is supposed to make it work? But where are all those people who are going to make this rejuvenation and corporate renaissance possible? Many of them are gone-lost in downsizing, synergies, and rightsizings

Jan 1, 1998

By Dan S. Nilsson

Small-scale mines are today expected to provide much of the increased production of metals, industnial minerals and coal this country demands in the future. But what is the size trend in the mining industry?

Jan 1, 1980

By Greg Ford

Each year, companies spend millions of dollars on safety training and on safe equipment, money that is generally well spent. Despite that, we still make mistakes. What happens if the mistakes are made not because of inadequate training, but because we are hard-wired to act in a certain way? If you read any of the ?Because of Human Error? text boxes in this document, situations like these may look familiar in your own workplace. ?The issues of risk, health, safety and the environment are getting more attention now than ever before, at all levels of the organization,? said Calvin Price, vice president of Global Health and Safety at LNC-Lavalin Inc., a company with 21,000 workers worldwide. Most would agree with Price that attention to safety is increasing because responsible companies care about their workers and the workers? colleagues, families and communities. However, cynics might say that the safety spotlight is powered by the corporate bottom line. Direct costs created by workplace injuries total $51.8 billion annually and include workers? compensation payments, medical expenses, civil liability damages and litigation expenses. This sum represents a staggering one quarter of each dollar of pretax corporate profits. Indirect costs may run as much as 20 times the direct costs of on-the-job accidents and illnesses. Examples of indirect costs include training replacement employees, investigating the accident and implementing corrective measures, lost productivity, repairing damaged equipment and property, and costs associated with lower employee morale and absenteeism. What?s interesting is that up to 90 percent of incidents are due to human error, not faulty equipment or other factors.

Aug 1, 2013

By Allan M. Harvey

Asbestos production in the United States is no match for the vast operations of Canada and the U.S.S.R. The majority of U.S. production is limited to the states of Vermont, California and Arizona, and the type of asbestos is limited to the variety of serpentine known as chrysotile. What little production of other varieties of asbestos such as tremolite and anthophyllite that has occurred over the past 100 years since asbestos became a useful commodity is of practically no significance. However, new developments in the field of environmental and occupational health hazards has startled the mining industry in this country and has already given a few particular companies reason to be concerned about the profitability and probability of their continued operation in the business of mineral processing. At the heart of these developments is the question and controversy over just what constitutes asbestos and what exactly is the definition of a fiber. To the mineralogist or, in fact, to practically anyone engaged in the process of mining and separating minerals there is little or no question about asbestos. It is not a distinct mineral but rather a commercial product serving specific applications for which a number of fibrous mineral types can qualify. To the hygienist pr health authority this definition is too general. They demand something they can detect, measure and control. To suit their purposes and simplify their task of detection, they have labelled the minerals chrysotile, crocidolite, amosite, tremolite, anthoph-yllite and actinolite as asbestos, and any particle of these minerals with an aspect ratio of 3:1 as an asbestos fiber. It does not

Jan 1, 1976

By H. E. Rudi

The advent of open nit mining permitted the development and processing of minerals never before thought possible. New equipment was needed; new techniques were devised; new methods were called for. This development and acquisition of new techniques, methods and equipment did not, however, stir the souls of our industry and educational leaders sufficiently to a recognition of the problem of people, especially the future development of the people needed in open-pit mining. The people problem has been and will be with us as long as there are two of them. The development of people will be required for the same reason. The problem of developing future personnel for open-pit mining is not what must be developed; that is known to all of us and can be briefly stated ashore and better of everything." As I see it, the real problem lies in determining (1) what personnel are really critical, (2) why are they critical and (3) how can we develop them.

Jan 1, 1965

By Swan. J. D.

Repairing and replacing equipment damaged by corrosion and abrasion is a major cost throughout industry, especially in the coal mining industry. Careful study of corrosion and abrasion, and their causes and effects, often leads to the selection of alternative materials which can provide economies. What, actually, are corrosion and abrasion and how do they contribute to the cost of operating a coal-preparation plant? Furthermore, what can be done to alleviate corrosion and abrasion problems and thereby reduce operating costs? These questions will be answered in the following discussion, which will describe the destructive action of corrosion and abrasion and give several methods for controlling corrosion and abrasion losses, These methods include the substitution of stainless steel for carbon steel, the use of corrosion inhibitors, and the use of design to eliminate corrosion and abrasion. Examples will be given illustrating the benefits that have resulted in plant tests when these methods of controlling corrosion and abrasion were used.

Jan 1, 1970

By David M. Koogler

If you are contemplating starting a small coal mining operation there is a good possi¬bility that you can not afford it. If you, have already started, you may be on the road to bankruptcy. If you are a small but well established operator you may be trading dollars, or even dissipating your capital, equipment and other assets. A bleak outlook? Yes! Meant to be discouraging? No! Just a reminder that, with todays costs of doing business, high interest rates, rapidly increasing costs and decreasing sales prices, a small businessman/miner had best watch closely or he will be mired in something worse than a soft bottom - namely a cash and credit shortage, and in too many instances In recent times, bankruptcy. We will not dwell on what happens once you are that far gone, though I could cite a good example. But, let us look at what should be done to avoid such a catastrophe.

Jan 1, 1981

By Malcolm D. Flavel

As indicated in the introduction to this paper, it is a sequel to that which I gave to the last annual meeting in Atlanta in march. This paper goes further into aspects of crushing and screening, primarily from the standpoint of circuit control. There has been little published by equipment manufacturers on this subject and this is the first paper on crushing circuit control to be sponsored by Allis-Chalmers corporation. By proper control over the use of crushing energy, we will be able to produce finished products from feed materials uti¬lizing minimum capital for the lowest cost of production. The subject will be discussed as follows. Firstly, we will look briefly at what we are trying to accomplish; Secondly, what is presently available in the way of technology; Thirdly, we will look at a suggested new system of control which will best fit the parameters of the normal crushing and screening operation; As a conclusion, I will summarize the advantages of the new system.

Jan 1, 1977

By William J. Wasko

Maintenance of mining equipment has become so complex and important from a cost and product ion standpoint that the organization must be set up in an engineering fashion to be successful. Production costs are greatly affected by proper maintenance. Tonnages can only be met when operating time is at its maximum and breakdown time is at its minimum. Last, but equally important, large capital expenditures must be protected and improved The effectiveness of the maintenance program will, in many respects, be a direct, result of the effort put torch in developing the overall program. Once the need of maintenance is realized, the next step is to determine what the organization should be and what it should accomplish. Follow through is then most vital. Preventing machine breakdowns and reducing maintenance costs are the primary goals of all maintenance organizations. Good preventive maintenance, a system for inspecting equipment and a complete record of inspections will help attain these goals.

Jan 1, 1966

By Carl R. Christiansen

Excellent underground industrial sites and warehouse facilities have been constructed in Europe and at several locations in the United States. Many quarry and mine operators are considering, or should consider, the possibilities of the development of their mineral properties in such a manner as to make underground space that is suitable for a secondary industrial use. Before proceeding with mine or quarry development, the operator should answer the following questions: 1) Is there a need for underground industrial space in your geographical area? 2) Is your deposit suitable for development of space for industrial usage? 3) If the deposit is suitable, what methods of development can be used? 4) What are the comparative economics of the different methods of space development? An honest analysis of the first two questions may eliminate the need for proceeding to the third. Affirmative answers to questions 1 and 2 should be followed by the engineering and economic studies required in response to questions 3 and 4.

Jan 1, 1975

The gases transportation and adsorption in the coal are greatly dependent on the pore-crack parameters, such as the porosity, the pore distribution, as well as the number and size of the pores. What?s more, the pore parameters of the coal are always changing with the temperature. However, the pore characteristics and their changes are extremely difficult to quantify. In this case, Fractal Theory provides a good tool to address this issue. Based on this theory, the pore distribution coupled with the size of the pores can be quantitatively described. In this paper, the equation used to calculate the Fractal Dimension of coal pores was deduced and Mercury Porosimetry was employed to test the pores distributions of coal samples at different temperature. The experimental data excellently verified the Fractal characteristics of coal pores. In addition, the experiments also indicate that the Fractal Dimension of the coal pores linearly increases with the temperature.

Jan 1, 2012