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By A. Warczok, C. M. Diaz, A. Bergman, T. Utigard, M. Barati

The world wide consumption of energy is steadily increasing and by 2030 it is forecasted to grow by another 50%, leading to mounting political and economic pressures. For any pyrometallurgical operation, it is therefore paramount to investigate and implement methods to decrease the use of energy. In the pyrometallurgical processing of steel, copper, nickel and other high temperature metals, a large amount of energy is lost in hot off-gases, molten slags, mattes and molten metals. Most of this energy is generally lost during the cooling and solidification steps with very little focus on energy recovery or reuse. In this paper we will quantify how much energy is contained in the various slag streams, then review previous attempts and methods employed to recover some of this energy, and finally evaluate some novel technologies that could potentially be employed.

Jan 1, 2011

This summary of State laws on explosives wag compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and, in general, how they have been treated. It does not Include any legislation passed after 1942, or any proclamations, regulations, or administrative orders. It does not purport or attempt to be authoritative. If any problem arises involving interpretation of the statutes of any particular State, the original source must be consulted for the exact words used by the legislature. This summary, however, will be useful in determining whether relevant statutes exist, and in locating them quickly, with a minimum of effort. It will be of value also in comparing statutes in other States to determine what construction has been placed upon them by the courts of these jurisdictions or to contrast the varying provisions of many States upon a similar subject. To make these comparisons easier, the statutory provisions for each State have been grouped under several major topics in outline form. Although this sometimes has resulted in disruption of the continuity of individual acts, the increased general clarity and availability of comparable sections have more than justified the procedure followed.

Jan 1, 1943

By F. E. Block

The metallic reduction of vanadium chlorides was investigated by the Federal Bureau of Mines as a possible new route for preparing vanadium metal in an effort to develop a production process that would be adaptable to large-scale plant production and would yield metal of uniformly high quality. Vanadium tetrachloride was usually prepared by chlorinating vanadium pentoxide in the presence of carbon. Although oxygen-?free tetrachloride was difficult to prepare this way, it could be prepared by the direct chlorination of vanadium carbide. Lower valent vanadium trichloride was prepared by the thermal decomposition of vanadium tetrachloride. Vanadium dichloride was also prepared by the thermal disproportionation of vanadium trichloride.

Jan 1, 1961

Cyanide is reactive to copper minerals and is not suitable to extract the gold from the copper bearing ores. Ammoniacal thiosulfate is considered an excellent alternative lixiviant for leaching copper bearing gold ores. Unfortunately the results of high reagent consumption and poor gold ex-traction were found by thiosulfate leaching of synthetic gold ores containing chalcopyrite, chalcocite or bornite and a mild refractory copper-bearing sulfidic gold ore. In this investigation, several processes have been applied to reduce the impacts of these minerals on gold leaching. The process included: the pre-oxidation of copper sulphide minerals in water or ammonia solution, the reduction of dissolved oxygen in the lixiviant (0.3 ppm DO or 0.7% oxygen), adding phosphate anion in the leach or pre-leach stage, and the addition of a strong copper ligand (e.g., EDA and DETA). The results indicated that the gold extraction could be improved to 93% with the thiosulfate consumption being reduced to less than 8 kg/t. The dissolution of copper minerals was found to be the major reason for increased consumption of thiosulfate and the highly reductive leached surfaces are responsible for the reduced gold extractions.

Jan 1, 2014

By R J. Soriano, S Ciutina

The Masbate gold deposits are situated on the island of Masbate, 350 km south of Manila. A new plant was commissioned in April 2009. The grinding circuit consists of one semi-autogenous (SAG) mill Ø9.75 m × 4.27 m, two ball mills Ø5.6 m × 7.1 m and a pebble crushing circuit, which is usually called a SAG-ball mill-crusher configuration. The SAG mill was originally equipped with radial pulp lifters. The mill runs at fixed speed of 10.9 rev/min, which is approximately 80 per cent of critical speed (per cent CS). Due to the high speed of the mill the original radial design pulp lifters presented a high volume of recirculating load inside the chamber and consequently heavy wear on the outer circle (bottom pan).In order to address the high wear on the pulp lifters a number of avenues were considered in early 2011. The chosen solution was to change the geometry of pulp lifters from radial to curved design. The pre-existing drilling pattern on the discharge end of the mill was a major constraint. A number of designs were considered. The selection of the most suitable option was to be made based on 3D discrete element modelling (DEM) and smoothed particle hydrodynamic (SPH) simulations.The original radial design and two potential solutions for curved pulp lifters were simulated with 3D DEM and SPH software. The main three objectives were predicting the charge dynamics, the expected wear patterns and discharge efficiency. One of the solutions was chosen and implemented during 2012.Observations carried on after installation of the curved pulp lifters have confirmed, as expected, a reduction in wear intensity on the outer pulp lifters. In addition to this, at early stages of operation with curved pulp lifters, the mill operator noticed a reduction in energy consumed by the mill with no detrimental effect on mill performance.This paper is intended to further study the effect of curved pulp lifters on mill energy consumption.CITATION:Ciutina, S and Soriano, R J, 2014. Curved pulp lifters – can they save energy?, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 109–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By M Scoble, A Ostry, J Shandro

Mining companies are not ill-informed on the topic of community health. There have been a number of research studies that have illuminated community health issues associated with mining, especially in the western Canadian province of British Columbia. However, what is missing amongst the literature is the perspective of mine managers and mining executives on this topic. This is important as mine managers and executives face a number of issues related to community health and are under pressure to consider the topic in more detail. This paper presents results from an exploratory qualitative investigation based on grounded theory research techniques into current community health considerations from the perspectives of mine executives and mine managers working in Western Canada. Interviews were conducted between February and May 2012 with 11 mining versus ten mining executives and managers who represented operating mines or mining umbrella organisations in Western Canada. Participants report on general community health issues that are perceived to be important, the perceived role that the mining sector should play?in contributing to community health and how this differs in Western Canada as compared to locations abroad, and?risks companyÆs face in making community health contributions. This paper concludes by drawing attention to pressing health needs that are present in Northern, rural and Aboriginal populations in Western Canada and provides a platform for future research initiatives focused on improving the health and well-being of communities associated with the mining industry. CITATION:Shandro, J, Scoble, M and Ostry, A, 2012. Community health considerations from mining executives and managers in western Canada, in Proceedings International Mine Management 2012, pp 97-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By Ahmad Ghahreman, James McNeice

"Cerium is the most abundant rare earth metal and is often found in deposits along with small amounts of more valuable metals such as neodymium and gadolinium1. As a result, the production of cerium oxide often exceeds market demands, thus in some cases it would make more sense to remove the cerium from the process solutions before further purification. A common method of cerium removal is to precipitate CeO2 from the acidic leach liquors by raising the pH to oxidize cerium(III) to cerium(IV). This study investigates the oxidation kinetics using three oxidants; hydrogen peroxide, sodium hypochlorite, and potassium permanganate. The effect of oxidant, pH, cerium concentration and temperature on the oxidation kinetics will be discussed. Cerium oxidation in solutions with pH ranging from 1.0 to 4.0 was investigated at cerium concentrations ranging from 2.0 g/L to 16.0 g/L. A cerium recovery of 40% can be achieved at different conditions with each oxidant at room temperature, with higher recovery at 60°C.INTRODUCTION Over the last 70 years, the rare earth elements (REE) have become crucial components of modern technology. These metals are categorized as light rare earths (LREE) or heavy rare earths (HREE) by governments and miners based on weight, abundance, and therefore value. The minerals bastnaesite, monazite, and xenotime compose the majority of the world?s exploitable sources of these metals (Binnemans, 2013; Parker and Baroch, 1971). Geologists classify the LREE ores as „cerium group? minerals, approximately 50% cerium oxide by weight. The cerium group minerals monazite and bastnaesite compose the majority of world production, leading to an overproduction of cerium relative to world demand. This ratio of light to heavy REE in deposits has led to a phenomenon referred to as the balance problem (Binnemans et al., 2013). As an example, to produce 1 tonne of europium oxide from a bastnaesite deposit 450 tonnes of cerium oxide must be processed. This means that any push to increase production and access the value of the HREE metals will drive down the value of the LREE metals leading to diminishing returns (Zepf, 2016). These ores also contain measurable levels of thorium, subjecting them to complex radioactive waste regulations. During the 20th century, the USA was the largest producer of rare earth metals (REMs), primarily sourced from the Mountain Pass mine in California. However, due to a combination of market dynamics and regulations, China has dominated the market for the last two decades. The largest Chinese REE mine, Bayan Obo, produces rare earth (RE) concentrate as a byproduct of iron mining, decreasing their relative production costs (Gupta and Krishnamurthy, 2005). This mine alone represents about half of world bastnaesite production (Zhi and Yang, 2014). Rising demand for high-tech products has forced Chinese producers to commission other large mines, climbing to 90% of world production in the early years of the new millennium (Mancheri, 2016). This presents the west with a looming supply risk of these critical metals in the future."

Jan 1, 2017

By P D. Munro

On the occasion of the 14th Mill Operators’ Conference and marking 40 years since the first one was held in Mount Isa in 1978, it is fitting to review the history of the Conference and its development over that time.The first 10 Conferences were irregularly held at three to four year intervals, with 9 of these in regional centres of Australasia. It is only since 2012 that the Mill Operators’ Conference has become a regular biennial event, alternating with the MetPlant Conference.The number of people attending the Conference has more than doubled to 470 delegates at the 13th one in 2016. It has outgrown its regional beginnings.Papers presented to the previous Conferences have been analysed according to commodity, country of origin, technology and theme plus the affiliation of the authors to discern any trends that may assist in planning the future events.Suggestions are made as to how the AusIMM might wish to arrange its mineral processing/metallurgical conferences.Recent changes to the structure of the Conference providing a more meaningful experience for the delegates and increasing their interaction and involvement should be vigorously pursued.CITATION:Munro, P D, 2018. Mill Operators’ conferences – a 40-year retrospective and a vision for the future, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 5–14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By J. R. Ruark

Because of the importance of oil-shale reserves the Bureau or Mines resumed research investigations in this field beginning in 1944. The Bureau early decided to build a Large-scale demonstration plant to accomplish the dual purpose of obtaining design data and to produce crude shale oil for refining studies. Two 40-ton-Capacity batch N-T-U (Nevada-Texas-Utah) retorts were completed for this purpose in 1947. After a preliminary operation, the plant was used to investigate process variables of air rate, recycle gas rate, and shale particle size and crude. Correlations obtained from these variables are presented in this report. Researchers concluded that recycle gas was not necessary for efficient operation of the process. Short comings of the batch method of processing the oil shale are pointed out in the report. Several periods of prolonged production operations were carried out. During these periods, the retorts were operated to produce as much crude oil per day as possible. The lifetime operation of the N-T-U retorts was divides into three periods, namely, preliminary operation, process variable study, and production operation. During the preliminary operation, 187 runs were made with a total of 7,596 tons of raw shale used to produce 3,688 barrels of crude shale oil. During the process variable study, 179 runs were made with a consumption of 7,494 tons of raw shale and a production of 4,218 barrels of crude shale oil. The production operation consisted of 554 runs in which 22,457 tons of raw shale was used to produce 12,359 barrels of crude shale ail. The overall total for the lifetime operation of the retorts consisted of 920 runs with a total consumption of 37,547 tons of raw shale and a production if 20,265 barrels of crude shale oil.

Jan 1, 1956

By I. S. Parrish

The Sullivan Mining Group has been exploring the mineral deposits of the Mount Pleasant area of southern New Brunswick since 1967. Sullivan geologists have logged over sixty miles of drill core, mapped over five miles of underground workings and studied numerous surface exposures. Several mineralized zones have been defined and two higher-grade porphyrytungsten bodies delineated. Within these bodies, wolframite occurs as disseminated specks and grains up to one-half inch in diameter. The host rock is a brecciated rhyolite porphyry that has intruded quartz-feldspar porphyry of Mississippian age . The host rock is itself intruded by an acid porphyry called transition rock and is underlain by a microgranite. The mineralized zones, host rock, transition rock and microgranite are all thought to be derived from the same magma, and to represent progressive fractions from that magma.

Jan 1, 1978

By W. W. Adams

Two important facts stand out as features of the metal- and nonmetal-mining4 industry of the United States in 1941 as compared with 1940: First, the number of employees and man-days of employment increased; second, accident-frequency rates, both fatal and nonfatal, decreased. Reports from mining companies to the Bureau of Mines covering underground, open-pit, and surface operations for 1941 re¬vealed the largest number of men employed since 1926 and the largest number of man-days worked since 1929. The combined fatal and non¬fatal accident-frequency rate for 1941, calculated on a basis of one mil¬lion man-hours of exposure to hazard, was (except for 1931 and 1932) the lowest since 1911, the earliest year for which figures are available. During this 31-year period, only 1938 and 1939 showed lower fatality rates, and only 1931 and 1932 had lower nonfatal-injury rates. Operating companies reported that 9,620 mines were active during all or some part of the year. These employed 125,290 men, an increase of more than 4 percent over 1940. The total volume of work performed at all mines, measured in terms of man-shifts, increased to nearly 32 million, a gain of 10 percent; man-hours of employment rose to almost 254 million, an increase of 10 percent over the 231 million man-hours worked in the previous year. The year's operations resulted in an average work-year of 255 days per man, an increase of 13 days per employee over the average working time in 1940. Although the 8-hour day prevails generally at most mines, the industry as a whole averaged 7.94 hours per shift, as in 1940.

Jan 1, 1944

By L. J. Defferding

This report documents the work performed by Battelle-Northwest and its sub-contractors in Phase I of a project to develop a cross pit conveyor system for the Bureau of Mines. The conveyor system description includes details of the conceptual design as well as system and component specifications. The selection of primary and back-up sites for system demonstration is discussed. Maneuvers and operating sequences required for mining the selected demonstration site are described and illustrated in detail. Economic viability of the cross pit conveyor system was analyzed by estimating the cost of overburden removal per ton of coal using the Battelle-designed concept and comparing these costs to the cost of an available state-of-the-art 30-yd3 dragline operation. Testing and trade-off studies conducted are documented and the results presented. Alternate designs considered in developing the selected cross pit concept are included for completeness. Based on the evaluation of the selected concept, it was concluded that the cross pit conveyor system proposed by Battelle is a technically and economically feasible overburden handling method with a good potential to improve western coal mining efficiency.

Jan 1, 1976

By C. H. Buck, A. J. Taylor

"In 2015 Vale’s Clarabelle Mill began the process change to enable a higher degree of Cu separation. The flowsheet modification was part of a complete divisional flowsheet change being implemented in Vale’s Sudbury Operations. This paper will centre on some of the Operational Readiness (OR) work, culminating in the commissioning of the circuit in March 2017. The emphasis will be on the implementation of an integrated test plan to prepare for the process flow change through the mill.BackgroundClarabelle Mill (CBM) began making a saleable Cu concentrate in 2006 with the installation of the Cu separation circuit. Typical separation rate was 35-40% of Cu in feed reporting to Cu concentrate based on a target Ni concentrate Cu:Ni target of 0.7-0.8. The remainder of the recovered Cu (55-60%) reported to Ni concentrate and was smelted through the Copper Cliff Smelter.In 2013 a capital project, Surface Facility Upgrade (SFU), was implemented to focus on matching the surface plants capacities with the future mine plan to maximize revenues. This was to be achieved by redistributing the metal flow, specifically Cu, through CBM to increase metal unit content through the Smelter. The amount of redistribution of Cu was determined to be based on maintaining a stable Cu to Ni ratio (Cu:Ni) in the Ni concentrate.The change in Cu:Ni ratio in the Ni concentrate would affect the Sudbury divisional flowsheet, and required process changes across the all of the surface plants. The detail that surrounds the flowsheet changes as a whole will not be discussed, but the outcome of the decisions plays a large role in the operational readiness interactions between the mill, its suppliers and its downstream customers."

Jan 1, 2018

By Rodolfo Dal Alva Pinto

Uma linha contínua não só melhora o conforto aos usuários, mas também melhora as condições de desgaste, fadiga e manutenção dos equipamentos ferroviários. Porém os parâmetros de soldagem devem ser bem especificados e controlados de forma a obter uma junta soldada adequada. Neste trabalho foi desenvolvida a avaliação do desempenho da soldagem aluminotérmicas de trilhos. Os resultados obtidos foram empregados em ações de melhoria da qualidade da soldagem aluminotérmica, conforme relatado em outro trabalho apresentado neste evento.

Aug 16, 2017

By C. Musingwini

The South African mining industry continues to be a major source of employment at a time when at least 25 per cent of the working age population is unemployed. At the same time the industry faces a skills shortage in many of the disciplines necessary for its future health. The University of the Witwatersrand, University of Pretoria, University of Johannesburg, and University of South Africa have historically produced mining graduates for the South African industry, with any shortfall being met by the recruitment of overseas graduates. More recently the global shortage of engineers and other mining industry professionals has seen a reversal of this trend and a very significant emigration of well-educated and highly skilled personnel. The traditional career path for mining graduates is in production and mine management. However, there is the parallel and possibly more pressing need for specialized skills in such fields as ventilation, rock engineering, mine planning, mineral resource evaluation, and mineral asset valuation. It is in these essential areas that chronic shortages continue to hamper the development of the industry and may well frustrate its ambitions to be safe, healthy, and profitable into the future. The permeability of skills across sectorial boundaries within the mining industry requires that skills shortages in the platinum sector are not looked at in isolation, but within the context of the entire industry. This paper reviews the efforts being made by the universities at both undergraduate and postgraduate levels to meet the needs of the South African mining industry, in terms of the required numbers and the range of specialized skills.

Jan 1, 2012

By C. Pichler, C. Benigni, J. Antrekowitsch

"The recycling of steel mill dust results in zinc oxides which are sold to the primary industry in or-der to recover zinc in its metallic form. Due to the contained impurities - chlorine and fluorine - these sec-ondary oxides are usually charged into the roaster together with primary concentrates. Appearing problems in this furnace limit the application of secondary materials. Based on the zinc amount, a direct leaching, assumed that a low halide concentration is present, would be possible. To use the zinc solution directly in the electrowinning stage, the concentration of impurities, first of all iron, is limited. Iron can be found in secondary zinc oxides due to carry over during the recycling process. In order to reduce the iron content in the solution, the leaching has to be pH-controlled. This leads to a limited number of simple purification steps before the solution enters the electrolysis. Various trials were performed to evaluate the influence of temperature, time and sulphuric acid concentration on the iron dissolution. This paper deals with the results and also focuses on other impurities such as halides. Additionally, the soda washing process, usually done with secondary zinc oxides to remove most of the halides, and the challenges within this step are discussed.INTRODUCTION Recycling of steel mill dust, which is the main zinc containing residue, in the Waelz process dis-plays the common method worldwide. The product of the process is a secondary zinc oxide which is con-taminated with different elements like lead, iron and halides due to mechanical carry over or evaporation. Depending on the feeding material the concentration of each element in the dust is varying. The zinc con-tent of the product, also called Waelz oxide, lies around 65–68%. Based on these values it presents an al-ternative to the primary concentrate for the production of metallic zinc. The contained halides limit the direct utilization in the leaching stage and therefore have to be reduced. State of the art is a soda washing process but also solvent extraction gives a possibility to remove chlorine and fluorine but the desired con-centration for the electrolysis is hardly reachable (Antrekowitsch et al., 2016) Iron is present as an undesirable component of such secondary zinc oxides due to carry over. During the hot acidic leaching of the secondary concentrate, iron is dissolved too. Based on the higher electrical potential iron has to be removed before the zinc solution enters the electrowinning stage. It is usually removed by precipitation as goethite, hematite or jarosite, which is the common precipitation residue (Ismael et al., 2003)."

Jan 1, 2017

By J. F. Barkley

"The fly-ash problem of the smoke-abatement engineer - who now might well be titled, ""Smoke and Fly-Ash Abatement Engineer"" - starts with the necessity for him to know what fly ash really is, what plants really create it, and how much is being created. Fly ash in this connection may be defined as all solid particles emitted to the atmosphere as a result of the combustion of fuel.COMPOSITION OF FLY ASHMuch can be learned about fly ash by studying samples with a strong magnifying glass or, preferably, a high-power microscope. As an example, figure 1 is a photomicrograph of an underfeed-stoker fly ash weighing 23.7 pounds per cubic foot, which passed a baffle-type cinder catcher and was caught by a Cottrell precipitator. Figure 2 shows a similar fly ash made at a higher stoker rating and weighing 36.2 pounds per cubic foot. The lighter ash contains more light, unconsolidated ash than the heavier. In both instances some of the ash has been fused to a glass, as is indicated by the spherical particles resembling marbles; however, the heavier dust contains more and larger spheres. With the faster burning and higher air pressures occurring at the higher burning rates, more of the larger fused spheres reached the precipitator.Such studies of fly ash frequently make possible correct determination of its source. For example, the Supreme Court Building, one of the finest of the Federal buildings in Washington, was having considerable difficulty with fly ash from some outside plant. It was thought to come from a nearby apartment house. A fly-ash trap was installed there, and care was taken in the operation of their underfeed stokers. The fly-ash nuisance continued. Microscopic examination of the fly ash found about the building compared with samples taken from the stack of the apartment house showed to the surprise of the accusing building superintendent that the present source was elsewhere. By the same means, the source was found to be a plant about ore-half mile away."

Sep 1, 1939

By K. L. Williams

The Bureau of Mines laboratory tested the response of a commercially available real-time aerosol monitor (GCA RAM-1) to various dusts. Monitor measurements were recorded, averaged, and compared with simultaneous gravimtric measurements of each test dust. Tests usually lasted several hours. The test dusts of various particle size distributions used included coal, limestone, and a commercially available test dust. For each particular dust, the monitor response was linear and correlated well with mass concentration over the range of about 0.5 to 10 mg/m3. The monitor can estimate a 2.0-/m3 respirable coal dust concentration within as little as 26 pct with 95 pct confidence. The monitor must, however, be calibrated with the dust to be measured because the instrument response is affected by the type of dust particle. The average monitor response to same mass concentration of coal dust was approximately twice the average monitor response to the same mass concentration of limestone dust.

Jan 1, 1984

J. L. CHRISTIE, Chairman T. S. FULLER, Past-chairman W. M. PEIRCE, Vice-chairman W. A. SCHEUCH, Vice-chairman E. M. WISE, Secretary International Nickel Co., Bayonne, N. J. W. M. CORSE, Treasurer Executive Committee H. A. BEDWORTH G. O. HIERS D. K. CRAMPTON R. H. LEACH E. H. DIX, JR. R. F. MEHL J. A. GANN J. WALTER SCOTT' JEROME STRAUSS Finance Committee T. S. FULLER, Chairman W. M. CORSE H. S. RAWDON C. H. MATHEWSON SAM TOUR

Jan 1, 1934

By Donald E. Ralston, V. Rajaram, Michael N. Greeley, John W. Peters, Terry J. Laverty, F. S. Kendorski, Peter G. Chamberlain, J. Brent Hiskey, William C. Larson

Preliminary figures from the US Mine Safety and Health Administration show 801 underground metal mines and 490 surface metal mines, at the end of 1981, up from 663 and 383, respectively, in 1980. Preliminary MASH figures also show 207 underground nonmetal mines and 1070 surface nonmetal mines at the end of 1981, compared with 167 and 1092, respectively, last year. In addition, preliminary MASH figures show there were 14,676 mineral extraction operations on the surface and 3845 underground at the end of 1981, versus 14,951 and 3675, respectively, for last year. The number of mines, then, in three of four categories increased significantly, while having a lower net total of just 2% in the other category. And the number of underground extraction operations increased nearly 5% for the year, while surface operations were down less than 2%. But despite operations totals that mostly held their own or showed significant increases, it was a tough year for the nation's mining industry. The nonferrous segment of the industry had a bad year and 1982 may be no better, according to Business Week (Jan. 11, 1982), which adds that a turnaround is impossible unless the general economy recovers. Even then, with diminishing markets and overcapacity plaguing its products, the mining industry's condition "will be far from robust," the magazine says. The basic problem is that nonferrous metals-aluminum, copper, lead, molybdenum, nickel, and zinc-are tied to the most troubled sectors of the US economy. As recently as 1979, for example, more than 40% of all aluminum shipments went to the construction and transportation industries. Last year, these markets were down to 35% of aluminum shipments. And molybdenum sales to steel producers dropped by nearly 15% last year. Moreover, nonferrous products ended 1981 at disastrously low prices. Molybdenum oxide sold at $8.77/kg ($3.98/lb), half its $17.63/kg ($8/lb) price earlier in 1981 and aluminum was listed at $1.08/kg ($0.49/lb), compared with $1.54/kg ($0.70/lb) a year earlier. The Comex price of copper was $1.54/ kg ($0.70/lb), down from $3.11/kg ($1.41/lb) in early 1980, in real terms the worst copper price in 30 years. Lower prices led operators to cut their output and increase layoffs, shut down mines, and defer capital spending projects. In December, Duval Corp., a Pennzoil Co. subsidiary, shut all four of its US copper mines until March. Aluminum Co. of America had laid off 7.3% of its work force, shut nine of its 38 smelting lines, and entered 1982 operating at only 68% of capacity. Inco Ltd., the Free World's largest nickel producer, lost money in 1981, an estimated $11 million, for the first time since 1932. And, like Falconbridge Nickel Mines and other major nickel producers, had cut back on nickel production and was operating at only 63% of capacity (Forbes, Feb. 15, 1982). Amax, the country's largest molybdenum producer, had cut production by 20%. And Hanna Mining Co. sold lead for $5.07/kg ($2.30/lb), about $1.54/kg ($0.70/lb) below what it cost to produce. Another problem is that copper companies in the next few years must come to terms with problems of aging smelters. Some companies are simply closing them. In 1980, Anaconda closed its 75-year-old Butte, MT, smelter and is shipping concentrates to Japan, rather than modifying the smelter to meet environmental requirements. And oth Phelps Dodge Corp. and Asarco Inc. have antiquated smelters on which they will have to make decisions. The most troubled metal in 1982, Business Week said, will be molybdenum, with no real recovery in sight until the mid-1980s. High molybdenum prices in the late 1970s, caused in part by shortages, triggered overexpansion that will take years for the US market to soak up. On a more upbeat note, 1981 mergers might help stabilize the industry by providing funds for mining companies. Standard Oil Co. (Ohio) said it plans to spend $7 billion on Kennecott during the next 10 years for modernization and expansion. And Atlantic Richfield Co. said it will spend $500 million on Anaconda Copper Co. during the next five years. Another positive note was sounded by T. H. Adams of the United Banks of Colorado Inc. He said he expects the mining industry to experience moderate growth in 1982, led by "interest rate sensitive" demand from energy, electronics, and defense markets. And mining will be helped by "weak, but improved" construction and auto markets. The mining industry will be operating in an economy stronger than 1981, but still relatively sluggish by postwar standards, Adams predicted. Iron Ore Estimated US iron ore production in 1981 was 75.2 Mt (74 million long tons), up 6% from 70.7 Mt (69.6 million long tons) in 1980, though down from the 87.1 Mt (85.7 million long tons) produced in 1979. The mine value of usable iron produced from domestic mines was estimated at $3 billion. US iron ore was produced by 28 companies operating 35 mines, 26 concentration plants, and 16 pelletizing plants. The mines included 34 open pits and one underground mine. Byproduct ore recovered from copper- and titanium-mining operations accounted for less than 1% of total iron ore production. Fifteen mines operated by nine companies accounted for 94% of total

Jan 5, 1982