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By Z Li, Z Yan, T Htet, S Zhang

During the pyrometallurgical processes, a substantial quantity of high-temperature ironmaking and steelmaking slags, generated at temperatures ranging from 1400 to 1600°C, is wasted, as the heat contained in these slags is released into the environment during the tapping process without effective utilisation. On the other hand, a significant amount of energy is required to reheat the cold materials for the manufacturing of glass and mineral-wool, often necessitating the addition of high-silica materials to facilitate the production process. In this study, an innovative approach is presented to harness the heat present in molten metallurgical slags to directly produce new raw materials for glass and mineral-wool manufacturing while simultaneously reducing energy consumption and mitigating CO2 emissions. The theoretical amount of waste glass that can be effectively added in the process has been estimated via thermodynamic calculation. Experimental assessments were conducted to examine the impact of high-silica waste materials on the dissolution, melting and fluidity. Potential recipes for glass and mineral-wool manufacturing were suggested and an assessment of the energy savings, and reduction in CO2 emissions with manufacturing of glass and mineral-wool using this innovative approach were included. It was determined that the processes could lead to a reduction of over 26 kg of CO2 emissions per 100 kg of new material used, primarily due to the utilisation of heat from slag and the accelerated smelting process.

Aug 21, 2024

By Joan Stoupa

The expansion of the West Point wastewater treatment plant located in Seattle, Washington, will require a permanent tieback retaining wall to enlarge the plant site for the new treatment plant facili­ties. The retaining wall will extend approximately 3,000 feet along the property boundary between the treatment plant and the neighboring Discovery Park. Wall heights will range from 35 to as high as 65 feet. The purpose of the retaining wall is to provide a more uniform grade on the plant site and to resist lateral pressures exerted by the upslope, unstable hillside. During preliminary design of the retaining wall, various wall systems were evaluated based on assumed subsurface soil conditions. Results of preliminary studies indicated that expected subsurface conditions and wall heights made a permanent tieback retaining wall feasible. However, uncertain loads on the wall and the capacity of anchors in the native soils were significant. As a result, a detailed geotechnical program was conducted. The scope of the program included conventional drilling, sampling, analyses, and a field test program to determine site-specific anchor capacities. This paper describes the anchor test program and results.

Jan 1, 1990

By Zbigniew Lubosik, Andrzej Walentek, Stanislaw Prusek, Sylwester Rajwa, Aleksander Wrana

"Underground coal gasification (UCG) provides a solution to supply electricity from high ash coal or deep deposited seams. The coal is consumed in situ, and, accordingly, the ash is left underground. UCG could play a major role in the future of coal, which is expected to fuel 44% of the world’s energy in 2030, in a more environmentally friendly and commercially viable manner. Nevertheless, it is known that the UCG can impact the environment. One of the most important factors in safe UCG process should be the evaluation of rock mass quality and the monitoring of its behaviour. The changes of rock mass parameters and quality have an influence on numerous aspects, such as subsidence and the stability of underground workings in georeactor vicinity, however, they also increase the possibility of pollutant migration through fractures and pores. These issues are especially important in cases of gasification conducted in an operating mine or on areas of high ecological vulnerability. This paper details observations made in two underground trials of UCG performed in Poland recently. The first of which is the Experimental Mine Barbara (under the project entitled HUGE-2 Hydrogen oriented underground coal gasification for Europe – Environmental and Safety aspects, (Wiatowski et al., 2015). The other trial has been conducted at an operating mine, Wieczorek, which is in the framework of a research project on the development of coal gasification technology for highly efficient fuel and electricity production (Czaplicka-Kolarz et al., 2013). During these trials, investigations were carried out aimed at assessing geomechanical parameters of rock mass and support behaviour in surroundings of UCG geaoreactors. Investigation comprises assessment of geomechanical parameters of coal, floor and roof strata, roof displacements, and concrete support strength parameters variation, as well as standing steel support load. Hydraulic penetrometer, endoscopic camera, Schmidt hammer, pull-out method, telltale, and ground penetration radar (GPR) were used in the investigation. Research conducted at both EM Barbara and Wieczorek Collieries revealed that the UCG process did not adversely affected the competency of rock mass (expressed by number of fissures and strength parameters of rocks), the stability of roadways and the support performance in the areas located in the vicinity of the georeactors."

Jan 1, 2017

By Jannie van Deventer

"Innovation in the minerals industry has been lagging behind comparable industries like oil and gas. An incremental innovation culture that tolerates long lead times between invention and adoption has been exacerbated by a research grant structure that inhibits radical idea generation. Entrepreneurs who can make the link between ore source, technology and finance will cause a shift in innovation culture and open up substantial opportunities in the minerals industry of the future. By extrapolating existing trends in technology within and outside mineral processing, a crystal ball vision of future innovation is shaped with the aim to lower energy and water demand, reduce CO2 emissions, decrease operating and capital costs, reduce environmental impact, and secure a social licence to operate. Advances in nanotechnology, advanced materials and biotechnology will impact mineral processing, but the initiative for technology transfer must come from mineral processors. Laminates of graphene oxide can offer efficient filtration and separation media, while microfluidic devices will be used for desalination, solvent extraction and analysis. Substantial progress is expected on benign lixiviants and separation agents, such as nanoscale supramolecular hosts that can serve as high-capacity, selective and recyclable ligands and sorbents, and solid aminobiphosphonate-based adsorbents. Radical ideas for the recovery of precious metals from non-assayable ores and the generation of energy above unity will be adopted in selected minerals projects. In-situ mining in which microbes generate lixiviants at mineral surfaces will simplify processing circuits. Specific ores will be subjected to microwave processing and electropulse liberation to enhance recovery. Ultrafine grinding using devices of low energy consumption will be done mainly dry, followed by dry separation. New flotation cells will remove efficiently either coarse particles or ultra-fine particles, with mineral surfaces being modified not just by new reagents but also by selective microbes. Innovation in mineral processing indeed has a bright future."

Jan 1, 2014

By Gary M. Larwood

A study was conducted to determine the amount of transportation equipment required to move 1.2 billion tons of coal in 1985. The Federal Bureau of Mines has investigated a majority of the various practices associated with coal transportation and has gathered information on the regional origin-destination patterns, methods of movement, equipment stocks, rate structures, and operational capacities of the most important modes of coal haulage currently in use. Models employing this information were developed to establish the origin-destination pattern for 1985 coal shipments, estimate practical tonnage capacities for selected coal hauling rivers, develop modal shares for both unconstrained (by river capacity) and constrained cases, and present a range of coal transportation equipment requirements for given sets of constraints. Projected transportation shares for rail ranged from 63.7 to 72.3 percent, and for river, from 8.8 to 16.4 percent. Other coal transportation modes (truck, conveyor, Great Lakes, and tidewater) are expected to retain their historic shares of coal traffic. Equipment estimates were made for 1985 rail and water transportation based on 1973 average and best practice. Average practice estimates ranged from 675,000 to 710,000 hopper cars (100-ton) and 3,100 to 5,940 barges (1,400-ton equivalent). Best practice estimates ranged from 126,000 to 142,000 hopper cars and 1,750 to 3,450 barges. Full implementation of 1973 best practice by 1985 is unlikely.

Jan 1, 1976

By Samuel P. Polack

This report reviews investigations to determine the fire hazard in coal mining when using flammable petroleum hydraulic oils to actuate mining equipment and summarizes research by the Bureau of Mines and industry on fire-resistant hydraulic fluids. Tests were established to evaluate fire resistance and the necessary characteristics to assure adequate service when fire-resistant fluids are used to replace petroleum hydraulic oils. The research was conducted in the laboratory and field trials under actual operating conditions in underground mines. Bureau of Mines Schedule 30 became effective December 17, 1959; the first approval was granted on February 18, 1960, and the twelfth was granted on March 17, 1961. The approvals include nine ready-mixed (by the producer) fluids and seven concentrates to which water is added by the user according to instructions from the producer. Seven synthetic-type fire-resistant hydraulic fluids submitted by two producers are also approved. Over 100 coal mines are now using water-in-oil emulsion-type fire-resistant hydraulic fluids in varying degrees from a trial in one machine to all the hydraulic equipment in an entire mine.

Jan 1, 1961

By N. de Koker, Y Jooste, J. Gerber

This paper presents a novel application of the boundary element method for numerical modelling of the seismic activity and hazard that is associated with the shaft pillar extraction at Bambanani mine in South Africa. In the numerical model, the tabular mining excavations are represented by displacement discontinuity elements, and to accommodate crush, shear, and fault slip seismic events, the numerical model is populated with additional displacement discontinuity elements that represent modelled crush- and shear-type failures in the rockmass. Crush-type failures are evaluated by applying the limit equilibrium method and a Hoek-Brown strength criterion, and shear-type failures are evaluated by applying a Coulomb-friction strength criteria to Ortleppshear and geological features. In this paper, the modelling results are presented as time history analyses of modelled potency from 1 January 2010 to 30 June 2022 and normalised exceedance rates for different mining periods using an upper-truncated power law. The normalised exceedance rates of seismic events that have moment magnitude Mw ≥ 1.0 are lowest for the initial mining period (26 events per year) and highest for the final mining period (218 events per year). The relative errors of the modelled potency and normalised exceedance rates are typically less than 10% or 15%, which suggests that the modelling methodology is appropriate for medium- and longer-term forecasting of seismic activity and hazard, as presented in this paper. Shorter-term forecasting is not considered in this paper.

Nov 24, 2025

By Xavier B. Starnes

"INTRODUCTION The Krausse Estate property was the site of the first lead silver mining in western Kentucky, which began with the sinking of the Andrew Jackson shaft in 1835 3/. The earliest miners considered fluorspar of no value and threw it upon the waste dump, but Crittenden County later became an important part of the western Kentucky and southern Illinois fluorspar district 4/, which has produced about 90 percent of the fluorspar mined in the United States. By 1945, approximately 35,000 tons of fluordpar ore had been produced from the Estate property.This property can be reached by traveling west from Marion on Highway 60 from 2.5 miles, than northward 3 miles. The road from the paved highway to the mines is very rough but not impassable even in bad weather. Ore is hauled 5 1/2 miles by truck to custom mills at Marion, a town of 2, 000 population, where the Illinois Central Railway was a freight station.Hurricane Creek runs through the eastern part of the property. The surface slopes steeply upward to west from the creek, and the topography is rough. The top of the hill is about 150 feet above the creek.The climate permits working throughout the year, but spring rains cause surface water to enter mine and water apparently drains southward along the fractured fault zones, so that when no water is being pumped at properties north of the Krausse Estate a heavy flow comes on the Krausse."

Sep 1, 1946

By G. Song

"SynopsisAccording to the overlying rock strength and thickness of 10 shallow coal seams in China, the strata are classified into four types: weak and laminated strata (hereinafter referred to as WL), weak and massive strata (WM), strong and laminated strata (SL), and strong and massive strata (SM). The four types of strata, together with longwall panel height (M), panel length (L), and seam depth (H) are factors that influence the loads on hydraulic power supports. Principal component analysis was used to study the seven influencing factors. It turns out that seam depth (H) is multicollinear with WL, WM, SL, and SM. Thus the enumerated seven factors are divided into two models. In Model 1, six factors; panel height, panel length, and layer thickness of the four type strata are involved. In Model 2, three factors; panel height, panel length, and seam depth are included. Using multivariate regression analysis, two equations to calculate loads on supports are obtained for each model. The equations were applied to shallow coal seams. The equation of Model 1 is more accurate than that of Model 2, but Model 2 could be further used in deep coal seams. The equations were coded through VB programming to simplify the calculation.IntroductionTo ensure coal production in the long term, the focus of coal mining has been gradually shifted to the western areas of China in recent years due to rich coal resources in this region. Most of the coal seams in this area are shallow but the support loads are abnormally high. In these circumstances, the chock loads estimating methods used in the past do not work. If the rated working resistance of a support is larger than needed, the shield is unable to fully perform, while a lower working resistance would lead to accidents like shield crushing or even casualties. This problem is frequently found in shallow coal seams such as Shenfu-Dongsheng, Yulin, Tuha, Lingwu etc. (Zhang, 2011). Thus, to ensure safety and efficiency during mining, the estimation of support loads and selection of supports are of great significance."

Jan 1, 2015

Satisfactory means of managing growth in boom towns is a concern in mineral, energy and other large industrial developments. This session will include examinations of socioeconomic impacts, major issues such as social disruption, case studies, methods of managing growth, and concerns involving Indian lands. Innovative methods will be offered to assist the public, government, and industry in finding solutions to managing growth in rapidly growing communities.

Jan 1, 1979

By Hayel M. El-Naggar, Sherif A. Akl

Although grouted piles have been used for several decades since the idea was proposed in the 1970s, their design is mostly based on experience and unpublished proprietary methods. There is little research on grouting drilled shaft tips and even less on grouting shaft sides. This paper presents the analysis of 4 instrumented pile loads tests on base and shaft grouted piles from different sites in Egypt; with emphasis on one of the tests, to demonstrate the analysis process. The data from the tests are analyzed to model the development of unit side friction (USF) with relative displacement. A numerical model using the finite element software PLAXIS is used to investigate the effect of grouting on the surrounding soil stress state. The paper combines the observations from full scale pile load tests and results from the numerical model to suggest an idealized behavior of side friction development with relative displacement of the grouted part of the shaft. The suggested model considers an envelope of Unit Side Friction (USF) with relative displacement, initially dominated by the grout resistance then at higher relative displacements, the friction with radially pressured soil takes over. The grout provides very high USF values up to a relative displacement of 2mm. Then, the USF drops to a typical pile soil side friction behavior; however, this friction is affected by the contact stress between pile and soil, which significantly increases due to compaction grouting. INTRODUCTION Base and shaft pile grouting has been significantly developing in recent years to accommodate the unfavorable conditions in major projects such as the high loads in high rise building and founding on problematic soil formations. Grouting aims to decrease settlements and increase the capacity of the pile under axial load. The technique is first introduced by Kraft (1974) but gained popularity in the 1980s. Typically there are two types of grouting; compaction, and permeation. Compaction grouting is more common in pile foundations practice, and many researchers have provided case histories of pile load tests on base grouted piles and base and shaft grouted piles (Gouvenot and Gabaix,1975; Stocker, 1983; Ghazali et al., 1988; Fleming, 1993; Kusakabe et al., 1994; Robson and Wahby,1994; Joer and Randolph, 1998; Hamza and Leoni, 1998; Mullins et al. 2000; Littlechild et al., 2000; Suckling and Eager, 2001; Dapp and Mullins, 2002; Ho, 2003; Fu and Zhou, 2003; Brettmann and NeSmith, 2005; Ruiz, 2005; Mullins, 2006; Dapp and Brown, 2010; Beadman et al., 2012; Nguyen et al., 2013; Miller et al., 2013; Sinnreich and Simpson, 2015; Hui and Lin, 2015). Compaction grouting is meant to densify the soil around the pile and below the base rather than permeate this soil and increase its cohesion. Research showed that grouting increases the capacity of the piles by a factor of 2~5. The variation in capacity increase depends on pile type, grouting process, and especially grouting pressure. Although there are many case histories of pile load tests on grouted piles but there is no well-defined agreed-upon method to predict grouted pile capacity as typically done in ungrouted piles. Few lab experiments discussed the shaft grouting effects on the soil especially the compaction grouting. The experiments concluded that the compaction grouting forms a homogeneous layer between the pile and the soil, and a residual effective stress is achieved simultaneously with a significant densification of the soil around the pile with noticeable decreasing in void ratio. (Fattahpour et al., 2015; Wang et al., 2015). Recently, studies used numerical analysis to investigate the behavior of the grouted piles and the changes in the surrounding soil (Chiang et al., 2013). That study presents a simulation of the base pressure grouting with a simple FE model and predicts the reduction of the pile settlement by 10 to 20%. Another numerical study using a complex model conducted by Zhou et al. (2017), pr

Jan 1, 2018

By D. R. Wilburn

his summary of international mineral exploration activities for the year 2011 draws upon available information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry and presents [ ] analyses of exploration activities performed by the mineral industry. Three sources of information are reported and analyzed in this annual review of international exploration: 1) budgetary statistics expressed in U.S. nominal dollars provided by Metals Economics Group (MEG) of Halifax, Nova Scotia; 2) regional and site-specific exploration activities that took place in 2011 as compiled by the USGS and 3) regional events including economic, social and political conditions that affected exploration activities, which were derived from published sources and unpublished discussions with USGS and industry specialists.

Jan 1, 2012

By Rick Frechette, Bryan Ulrich

Representatives from several mining operations in three western states left their mines behind for a day in February to discuss with their peers the issue of water. The event was Knight Piésold and Co.’s Roundtable 2007, held in Elko, NV. It was third such event put on by the company. The issue this year was site-wide water considerations.

Jan 1, 2007

By Y. M. Zhao

The separating performance of a pilot dry beneficiation system using a gas-solid fluidized bed was investigated with coal from South Africa. The coal used for the study has a low inherent moisture content, a moderate ash content, a moderate volatile content, a low sulphur content and a high calorific value. Its washability is moderate. Experimental results show that the separating quality of the fluidized bed drops gradually as the feed-coal particle size decreases. The probable error, E, values for 50?25mm, 25?13 mm and 13?6 mm coals were 0.04 g/cm3, 0.06 g/cm3 and 0.09 g/cm3, respectively. The cause of the differences in separating characteristics was analysed by particle dynamics and numerical modelling. Furthermore, the pilot fluidized bed was employed to separate 50-6mm coal. In this experiment the coal ash content was reduced from 23.74% to 11.79%, with a probable error, E, value of 0.07 g/cm3and a recovery efficiency of 98.26%. This indicates that the fluidized bed is applicable to the separation of coal from South Africa and has good separating performance and wide applicability. Keywords: feed-coal particle size; gas-solid fluidized bed; dry coal beneficiation; numerical simulation.

Jan 1, 2010

By Paul M. Tyler

The value of mica depends chiefly upon the size of the flat sheets into which it can be split and also upon whether it is clear or stained. Muscovite (white mica) and philogopite (amber mica) are the micas of commerce. Biotite (black mica) and other varieties are virtually unsalable. Vermiculite, an altered mica having the extraordinary property of expanding greatly when heated, preferably should not be classed commercially as mica. Mica is marketed as (1) cut or uncut block, (2) sheet, (3) splittings, and (4) wet or dry ground mica. In the United States, mica that will not yield flat films over about 1-1/2 inches square, or that is ruled, rumpled, or flawed in any way, can be sold only as scrap, its sole use being for making ground mica. Only sizes that will yield rectangles 1-1/2 by 2 inches or larger can be classed as sheet quality; slightly smaller sizes may be classed as punch, and under certain circumstances still smaller sizes, down to about 1 inch square, may be used for splittings, which are mostly a thousandth of an inch thick or even thinner. Splittings, however, are produced in large quantities only in British India, where labor costs very little. Even there the work is done mostly by children, who not only work cheaper but have a delicacy of touch that enables them to do the splitting faster and better. No mechanical process yet devised will permit ordinary splittings to be made economically in the United States.

Jan 1, 1938

By A. Whillier

Note: Hydraulic rock drills and their effect on the underground environment by A. WHILLIER, Pr. Eng Se. D., (M.tT.) (Fellow) In any situation where hydraulic rockdrills are used underground, it is evident that an amount of heat equivalent to the total electric input to the power pack would enter the ventilation air. Book review Australian Mineral Industry 1972 Review. Australia, Department of Minerals and Energy. NIM report Report no. 1691 The determination of zirconium and aluminium by 14MeV neutronactivation analysis. Automation in Mining, Mineral, and Metal Processing The International Federation of Automatic Control (IF AC) is to hold its second symposium on the above subject in Johannesburg on 13th to 17th September, 1976. V Simposio de Mineracao A symposium is being arranged for 6th to 9th August, 1975, in Ouro Preto, Brazil. ACHEMA 1976 The 18th Chcmical Engineering Exhibition-Congress and European Meeting of Chemical Engineering will be held in Frankfurt from 20th to 26th June, 1976, and thc Chemical Engineering World Congress Sixth Underwater Mining Institute The above Institute will be held on the main campus of the University of Wisconsin in Madison, U.S.A., on 2nd and 3rd October, 1975.

Jan 4, 1975

The Mineral Industry, Published by McGraw-Hill Book Co, New York, N Y. The Mineral Industry is an annual review of the mineral industry It is a standard and complete reference on the mineral industry for the year covered Through the cooperation of the A I M E its publication in 1933 was made possible Mineral Industry for 1930 contains sections devoted to the production, consumption, trade, market, uses and technology of the following headings: Abrasives, aluminum and bauxite, antimony, arsenic, asbestos (b), asphalt, barium and strontium, chromium (b), coal and coke, cobalt (b), copper, diatomite, fluorspar, gold and silver, graphite, gypsum, iron and steel (b), lead, magnesite, manganese, mica, molybdenum, nickel, petroleum and petroleum products, phosphate rock (b), platinum group metals (b), potash, precious and semiprecious stones (b), quicksilver, radium (b), uranium and vanadium, slate (b), sodium salts, sulfur, pyrite, sulfuric acid, talc and soapstone, tin, titanium and zirconium, tungsten (b), zinc, minor metals, minor nonmetals, ore dressing and coal washing (b). Sections marked (b) have appended a bibliography of recent literature on the subject. Each section is written by an acknowledged expert. Other volumes contain similar material Prices -The Mineral Industry, 1892-1930, vols. 1 to 39. Complete sets of this work, uniformly bound, except vols 25 and 26,

Jan 1, 1933

By M. Steyn

This article captures the intrinsic differences of thermal coal products, their utilization and their substitution characteristics. South Africa produces approximately 245 million tonnes of coal annually. Eskom consumes 46% (approximately 112 million tonnes), 26% (approximately 65 million tonnes) is exported, and SASOL Synthetic Fuels consumes 18% (approximately 44 million tonnes) and a further 9% (approximately 22 million tonnes) is consumed by domestic users in various different industries. Marketing theory contributes significantly to understanding the importance of technical product and quality appreciation and comprehension, encompassing elements of price, distribution, and promotion. Coal product specification is determined by the inherent geology of a resource and the number of complex actions to market the product to a specific consuming market. Sampling, analyses, beneficiation application, and an array of parameters contribute to matching thermal coal products to the value-in-use it provides to the different markets and its consuming industries. Coal producer shave come under increased scrutiny since South Africa has been experiencing electricity shortages since early 2008. General misunderstandings were declared on public forums and in the media by both legislators and the South African public since a perception developed that South African coal producers are exporting coal that could be utilized by Eskom.

Jan 1, 2010

By Craig J. Nelsen, J. Leroy Schutz

The Carache Canyon Prospect consists of a hypabyssal breccia pipe which intrudes a gently dipping sequence of Cretaceous Mancos Formation and Mesa Verde Group shales and sandstones. This sedimentary sequence is intruded by a number of Oligocene (34-30 Ma) calc- alkaline sills. The formation of the breccia pipe and its subsequent gold mineralization is related to the emplacement of an alkaline intrusive complex dated between 30-26 Ma. An exceptionally large block within the pipe provides compelling evidence that brecciated sills and sedimentary rocks form a relict stratigraphy that collapsed 400-800 ft (120-240 m) below their counterparts outside the pipe without substantial changes in stratigraphic position. Native gold and sulfide mineralization within and around the pipe occurs in fractures that are primarily controlled by competency differences between sills and sedimentary rocks and secondarily controlled by ductility contrasts between the relatively brittle Mancos Formation hornfels and the more ductile Menefee Group shales. The resulting pattern of gold mineralization is a series of stacked, tabular, mineralized sills and sandstone separated by barren shale in an annular region along the southwest margin of the pipe. A series of near-vertical, subparallel, sill and sandstone breccias separated by barren or weakly mineralized shale breccia occur within shallow levels of the pipe.

Jan 1, 1990

By Ivette E. Torres

Of the 15 selected non fuel mineral commodities detailed in table 12, only 3 indicated increases in worldwide consumption in 1992. As in 1991, decline in consumption levels of the selected commodities can be attributed to reduced levels of use in the former U.S.S.R. and Eastern Europe. Of the remaining 12 commodities, 2 magnesium and cadmium, stayed relatively the same, while the other 10, including iron and steel, all recorded decreases. Global consumption of iron ore is estimated to have fallen about 3.5 % or about 30 million tons. This is a greater decline than what was estimated for production of iron ore, which is down only 2.7% or nearly 26.5 million tons, suggesting an addition to stocks. The consumption trend for iron and steel has been declining since 1989. This has mainly been due to the continued drops in use in the former U.S.S.R. and Eastern Europe. Even as the European economy begins to turn upward, there may only be a slight increase in consumption of iron, steel, and cement, considering the high cost of construction needed to modernize factories and buildings in Eastern Europe. Many feel that the economies of these countries are limited by the current status of their industries.

Jan 1, 1994