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By R. R. Estill

THE rank of the Ruhr coal ranges from a high volatile bituminous coal to an anthracite, depending to some extent on the original depth of the seam. The average Ruhr coal corresponds to a soft bituminous American coal of a coking quality. The average thicknesses of individual coal seams being mined are also comparable (59 in. against 65 in. in the United States). However, consideration of seam conditions and mining conditions other than those just mentioned emphasizes differences rather than similarities with United States soft coal. In general, the Ruhr seams now being mined are much more folded and inclined than American seams. Dips of 20' and 30" are common in seams now being worked, and 30 pct of the coal reserves in the district are in seams dipping more than 35". Only on the tops and bottoms of folds do we find rather flat coal seams. In addition to the folding there is extensive displacement by cross faulting plus a certain amount of strike faulting of an overthrust nature, which results locally in doubling or omission of seams. Because of the long history of mining in the Ruhr, nearly all coal lying near the surface has long since been mined out, and we find that the average depth of mining is at present about 2300 ft below the surface. Deep mining, folding, and faulting result in seam conditions requiring a great deal more roof support than one finds in American soft coal mines. In fact only in the anthracite district and the Rocky Mountain and Pacific coal fields do we find somewhat similar conditions. It is easy to say, therefore, that the problem of mechanization of coal cutting and loading in the German mines is quite different from that which we have so effectively met in America with our mobile cutters and loaders, duck bill loaders, and a room and pillar system of mining our drift and slope mines. Partly because of more limited coal reserves, the traditional German mining system is largely the longwall method, which gives an almost complete coal recovery. Backfilling must be extensively practiced to protect the longwall faces, the over and underlying seams and workings, and especially the surface industrialized areas and barge canals. The German engineers have accordingly concentrated their efforts on the design of cutters, loaders, and conveyors suitable to longwall methods rather than room and pillar methods. Undercutters with cutter bars like American models have been in use in the Ruhr since well before World War 11. In 1941 they accounted for 8.5 pct of the production. This percentage, of course, includes coal which was undercut but nevertheless had to be broken down with air hammers or with explosives. The most common of these cutters is the Eickhoff Standard cutter (see fig. 1). This machine does about 95 pct of the undercutting in the Ruhr today, and is available with either compressed air or electrical power and in at least four different sizes. A variation of the cutter is this one with two cutter bars (fig. 2). At the end of 1947 about 200 of these machines and similar cutters were accounting for 13.2 pct of the total production, a production which was, however, only 60 pct of the 1941 production rate, so that the actual cutter tonnage was only up to a small amount over 1941. In 1941 about 3 pct of the production was accounted for by shearing machines making their cut perpendicular to the longwall face. They were similar to those used in the States. These machines are today considered obsolete and now account for only 0.7 pct of the total production. They are located at only a few mines and at present do not seem to have much of a future in the Ruhr. For the future, the Ruhr miner is looking forward to rather extensive mechanization of face work, with two major types of equipment being developed almost simultaneously. On one hand there is the development of cutter loaders for use in relatively hard coal. They represent the further extension of ideas developed after relatively long experience with the Eickhoff cutter. On the other hand there has been since 1942 an intense interest in the Ruhr in the development of face-stripping methods, particularly by the Kohlenhobel (coal plow) and its modification. At the end of 1947 these cutter loaders, Kohlen-hobels and scrapers together were actually accounting for only about 1.4 pct of total production while air hammers still broke 77.1 pct and as much as 1.2 pct was actually broken by hand picks. However,

Jan 1, 1951

By R. R. Estill

THE rank of the Ruhr coal ranges from a high volatile bituminous coal to an anthracite, depending to some extent on the original depth of the seam. The average Ruhr coal corresponds to a soft bituminous American coal of a coking quality. The average thicknesses of individual coal seams being mined are also comparable (59 in. against 65 in. in the United States). However, consideration of seam conditions and mining conditions other than those just mentioned emphasizes differences rather than similarities with United States soft coal. In general, the Ruhr seams now being mined are much more folded and inclined than American seams. Dips of 20' and 30" are common in seams now being worked, and 30 pct of the coal reserves in the district are in seams dipping more than 35". Only on the tops and bottoms of folds do we find rather flat coal seams. In addition to the folding there is extensive displacement by cross faulting plus a certain amount of strike faulting of an overthrust nature, which results locally in doubling or omission of seams. Because of the long history of mining in the Ruhr, nearly all coal lying near the surface has long since been mined out, and we find that the average depth of mining is at present about 2300 ft below the surface. Deep mining, folding, and faulting result in seam conditions requiring a great deal more roof support than one finds in American soft coal mines. In fact only in the anthracite district and the Rocky Mountain and Pacific coal fields do we find somewhat similar conditions. It is easy to say, therefore, that the problem of mechanization of coal cutting and loading in the German mines is quite different from that which we have so effectively met in America with our mobile cutters and loaders, duck bill loaders, and a room and pillar system of mining our drift and slope mines. Partly because of more limited coal reserves, the traditional German mining system is largely the longwall method, which gives an almost complete coal recovery. Backfilling must be extensively practiced to protect the longwall faces, the over and underlying seams and workings, and especially the surface industrialized areas and barge canals. The German engineers have accordingly concentrated their efforts on the design of cutters, loaders, and conveyors suitable to longwall methods rather than room and pillar methods. Undercutters with cutter bars like American models have been in use in the Ruhr since well before World War 11. In 1941 they accounted for 8.5 pct of the production. This percentage, of course, includes coal which was undercut but nevertheless had to be broken down with air hammers or with explosives. The most common of these cutters is the Eickhoff Standard cutter (see fig. 1). This machine does about 95 pct of the undercutting in the Ruhr today, and is available with either compressed air or electrical power and in at least four different sizes. A variation of the cutter is this one with two cutter bars (fig. 2). At the end of 1947 about 200 of these machines and similar cutters were accounting for 13.2 pct of the total production, a production which was, however, only 60 pct of the 1941 production rate, so that the actual cutter tonnage was only up to a small amount over 1941. In 1941 about 3 pct of the production was accounted for by shearing machines making their cut perpendicular to the longwall face. They were similar to those used in the States. These machines are today considered obsolete and now account for only 0.7 pct of the total production. They are located at only a few mines and at present do not seem to have much of a future in the Ruhr. For the future, the Ruhr miner is looking forward to rather extensive mechanization of face work, with two major types of equipment being developed almost simultaneously. On one hand there is the development of cutter loaders for use in relatively hard coal. They represent the further extension of ideas developed after relatively long experience with the Eickhoff cutter. On the other hand there has been since 1942 an intense interest in the Ruhr in the development of face-stripping methods, particularly by the Kohlenhobel (coal plow) and its modification. At the end of 1947 these cutter loaders, Kohlen-hobels and scrapers together were actually accounting for only about 1.4 pct of total production while air hammers still broke 77.1 pct and as much as 1.2 pct was actually broken by hand picks. However,

Jan 1, 1951

By Propser M, Szekely J

Flow maldistribution in the iron blast furnace has been studied analytically by the use of the vectorial form of the Ergun equation and experimentally via packed columns and a cold model of a blast furnace. Experimental results are presented showing the effect on fluid flow patterns of the following types of nonuniformities in a packed bed: the increased voidage at the wall ("wall effect"), the decreased voidage at the interface between layers of materials with different sizes and shapes, and the differences in resistance to flow of bulk regions of a column with different sizes and shapes. The proposed theory is applied to the calculation of fluid flow patterns for these nonuniformities. Velocity profiles, as calculated from these flow patterns, were found to agree reasonably well with experimental measurements obtained via hot wire anemometry techniques for laboratory scale packed columns. Calculated fluid flow patterns are presented for blast furnace burdens which show how flow patterns are affected by (a) coke segregation and (b) the relative differences in resistance to flow between coke and oxide pellet layers. For the cold model study, calculated flow patterns are presented based on photographs of a given burden distribution. The velocity profiles calculated from these flow patterns were found to agree reasonably well with the velocity profiles measured from the cold Model.

Jan 1, 1975

Exploration for uranium in Australia commenced only during the 1940s, but in this short period has been very successful as one third of the world's low cost uranium reserves have been discovered in Australia. Total uranium exploration expenditure in Australia up to the end of 1983 was $A(1983) 554 million; this discovered 20 potentially economic deposits and official reserves of 560 000 tonnes of uranium oxide at an average cost of $1 per kg of U 0 . An exponential 8 eserves indicates distribution of uranium r that there could be 54 undiscovered uranium deposits in Australia, each with reserves of 20 000 tonnes U308 or more, in addition to smaller deposits. Using a constant uranium price of $A(1983) 79 per kg, no deposit is economic at a grade below 0.12 per cent U 08 or with reserves of less than 3 000 tonnes. Selecting deposits with reserves of 5 000 tonnes U 0g or more as prime exploration targets, only 39 per cent of discoveries will yield a real internal rate of return (IRR) of 10 per cent or more. After committing a minimum exploration budget of $10 million to this search, an explorer has one chance between 7 and 12 of discovering a deposit that will repay the exploration investment.

Jan 1, 1984

"A growing public awareness of work-related diseases such as pneumoconiosis and the impact of this awareness on legislative bodies and on the skilled labour market are reasons why the Canadian mining industry must consider dust control of top-drawer importance. Measurements and standards related to the hazard are necessary to control a dust situation and to avoid excessive risk. The author discusses some of the methods of measurement, standards proposed and terminology used in this developing technology. The purpose primarily is to give a better understanding of the basic advances achieved by those who have applied current knowledge with a measure of success."

Jan 1, 1972

By AIME AIME

A REQUEST for information as to the details of activities of the Engineering Council was made by the Joint Conference Committee for the benefit of the new American Engineering Council. , This request was complied with, and the scheduled reply so succinctly sets forth the activities of the old Council as well as the scope of possible activities of ,the new Council, about whose efforts there has been much discussion, .that it' is given herewith in full, except the 'budget which is summarized.

Jan 1, 1920

By T. A. A. Quarm

The concept of a continuous zinc smelting process which employs submerged combustion of coal char for both heating and reduction is described. An estimate of the results of smelting a marmatitic zinc concentrate indicates that both the operating and construction costs would be lower than those incurred in processes now in commercial operation. The results of smelting a complex zinc-copper concentrate are also estimated, but no simple commercial process exists with which they can be compared

Dec 1, 1971

By Mary Sue Coates

Characterization of the rock mass in which deep underground structures are to be located is of critical importance to the feasibility and design of the structures. The process involves areal studies, subsurface exploration and extensive testing to obtain comprehensive data on the rock units which will enclose the excavated structures. The Illinois Deep Hole Project provides an example of characterization of rock at great depth describing the types and variety of tests and studies which were utilized and the results obtained.

Jan 1, 1984

By S B. Richardson, R E. Danell, D Mead, N T. Moxon

Explosives provide a very concentrated source of energy which is often well in excess of that required to adequately fragment the surrounding material. Blast design, environmental requirements, production requirements and the lack of detailed insitu geological data generally limits the degree to which the explosive energy distribution within the blasthole can be significantly altered using, for example, different explosive formulations or variable loading techniques. However, increased flexibility can often be exercised over a blast through the use of air-decks.

Jan 1, 1993

By Bruno Michaux, Markus Reuter, Martin Rudolph

"It is relatively well-established in the literature that the flotation of calcium minerals using fatty acids as collector is very sensitive to the process water composition. In particular, hard waters have often been reported to strongly reduce the target mineral recoveries due to the formation of insoluble compounds such as calcium and / or magnesium dioleate, thus reducing the amount of collector available for adsorption onto the mineral surface. In this study, the flotation of a fluorite pre-concentrate was performed with tall oil, an industrial collector essentially containing fatty acids. The tests were performed in a variety of synthetic waters to simulate multiple degrees of water hardness, and to differentiate the role of magnesium and calcium ions on the flotation performance. The flotation tests revealed that, under the studied conditions, a significant difference between flotation in calcium-rich and magnesium-rich waters was observed, suggesting strong ion-specific effects in the system. Specifically, calcium-rich waters slightly improved the fluorite recovery, whereas magnesium-rich waters caused a decrease in recovery by as much as 20%. This paper is focused on the flotation kinetics aspect of the system. This approach highlighted the interesting finding that calcium ions did not simply increase the fluorite recovery, but also significantly increased its flotation kinetics. The magnesium ions, on the other hand, had the exact opposite effect.INTRODUCTIONAs the mining industry is facing an increasing number of issues related to its fresh water consumption, the idea of using alternative water sources for mineral beneficiation is gaining significant momentum. As a result, a proper understanding of the role of water chemistry in flotation is becoming more and more urgent, leading to an increasing number of studies on this topic."

Jan 1, 2018

By Janice Reed

The first seismograph was developed around 132 AD. Much has happened since then. The “modern” seismograph (> 1920) has seen a lot of changes. From falling pin seismographs to magnetic tape units to today’s Z-curve analysis models, the blasting seismograph remains a necessary and useful tool to the blasting community. But why so many changes? What forces drive the advancement of the seismograph? There are many answers and aspects to this question. Research, regulation, and technological advances are the primary forces behind innovation in our industry. But these three forces also drive each other. Research drove our industry from displacement seismographs to particle velocity seismographs. Technology took us from 80 pound seismographs to units weighing less than 5 pounds. Regulation (and litigation) - the driving forces behind the Z-curve analysis units. How have these innovations helped today’s blaster? Have there been any negatives? It is important for today’s blaster to understand how we got here and why.

Jan 1, 2005

By William H. Hamilton

INTRODUCTION It was not very many years ago that tunneling machine manufacturers spent considerable time trying to convince contractors and mine operators of the advantages of mechanical tunnel boring over conventional drill and blast methods. Today there are few doubters left. There is universal agreement that, not only are tunneling machines here to stay, but the ratio of bored rock tunnels to blasted rock tunnels is increasing at an accelerated pace, and within the next twenty years I predict almost all tunnels will be bored by machine. I believe we are today at a very important mile-post in the development of tunnel boring systems. Felix Gaye stated in his recent article (1) "It is important to disseminate between the efficiency of cutting tools and the overall efficiency of the boring operation". Mechanized tunnel boring in the past placed almost total emphasis on the rock cutting and boring ability of the tunneling machine. With advancements in technology and better solutions to the problems of rock fracture, steering control, and structural design, the emphasis today can be placed on the total-system concept. Tunneling machine design, as one of the key elements in the overall system, presents many problems that are not totally solved today. These design problems are, in the most part, not related with rock fracture, but rather with criteria associated with the over-all operation.

Jan 1, 1997

By H. Soto

As a follow-up to a laboratory study, a pilot scale column for the flotation of coarse particles was designed and then tested in two different applications. In the first test, the concentration of a coarse phosphate ore (normally beneficiated by skin flotation in spirals) was carried out in a flotation plant in Florida. In the second pilot test, the column was used as a scavenger cell in the coarse flotation section of a potash beneficiation plant in Saskatchewan, Canada. Particle size of the phosphate feed was of the order of 0.6-1.0 mm and the potash feed 1-3 mm. The column was 1 feet diameter and was fed at rates between 0.5 to 1.4 tph. The effect of operating variables such as air and water flow rates, bubble size, frother concentration, residence time, sparger, etc were evaluated. The most important factors in column performance were found to be bubble size, air flow rate and the thickness of the froth bed. Best results were obtained in the absence of a froth bed, with low air flow rates and with small bubbles. The paper presents comparative performance and discusses details of the column design. Phosphate recoveries in the column were better than 90% whereas the conventional skin flotation circuit normally yields about 60% recovery for a comparable concentrate grade. Potash recovery from the tailings of the conventional flotation circuit was as high as 42% recovery. Particle size distribution of the potash concentrate was coarse enough to meet requirements for potash fertilizer.

Jan 1, 1993

By Frederick N. Rhines

BECAUSE of the nature of the environments in which metals are handled, it is natural that gases should be suspected of intruding into metallurgical operations, there to produce effects both beneficial and detrimental. The problem of tracing and controlling such effects is often made difficult by the complexity of the conditions surrounding 'their occurrence, even though the fundamental mechanisms involved may be simple and of familiar type. Many gas-metal reactions are known to be implemented by processes of diffusion. These form a homogeneous group of phenomena which become more readily understandable when viewed together, in that the knowledge gained from one serves to interpret the next. It is the purpose of the present paper to present, by means of examples drawn from practice, a brief survey, of the ways in which gas-metal diffusion serves and obstructs the purposes of the metal-fabricating industries. The selection of the cases described was made by consulting more than thirty-six practicing experts whose combined experience provided an extensive coverage of the field and who were in a position to supply examples of occurrences of present day interest. The response was generous and it is regrettable that space permits the description of only a limited number of typical examples with but brief mention of parallel cases. THE NATURE OF GAS-METAL DIFFUSION The term "gas-metal diffusion," although commonly used, is ambiguous in so far as it implies that a definite group of substances may be identified as gases and may be expected to behave in a manner distinct from other substances in association with metals. "Gases" such as oxygen and hydrogen when diffusing through a liquid or solid metal are properly components of the liquid or solid solution; they behave as alloying elements and are not to be distinguished in their diffusion characteristics from other elements, except that each has an individual rate of diffusion. On the other hand, a number of metals in certain temperature ranges are volatile to the extent that they may appear in the form of vapor in metallurgical operations. For the sake of greater definiteness, therefore, it will be convenient to- regard as "gas-metal diffusion" any process in which the result depends upon one or more of the diffusing elements appearing, at some stage, in the gaseous state, or as a compound gas. No element, gaseous or otherwise, can diffuse through a liquid or solid metal unless it is at least slightly soluble in that metal. The elements of low atomic number

Jan 1, 1944

By Michael Goldin, Jonathan Ladner, Thomas Peacock, Nathaniel Johnson, Patrick Haley, Kris van Nijen, Andrew Rzeznik, Pierre Lermusiaux, Matthew Alford, Carlos Munoz-Royo

Surface processing vessels for deep-sea nodule mining operations will produce dewatering plumes that will be released at some depth into the ocean water column. We are studying all aspects of this part of the nodule mining process. First, we have developed analytical and numerical models to determine the effects of highly non-uniform, realistic stratifications on forced, compressible plumes with finite initial size. The classical plume model is developed to take into account the effects of compressibility and thermal conduction through the dewatering pipe. Our results show how small-scale features of a realistic stratification can have a large effect on a plume, and provide a basis for determining at what depth dewatering plumes can be released. These results form the basis for our PLUMEX field experiments, in which we will study the dynamics of dewatering plumes over the course of one week of field tests from the vessel R/V Sally Ride. The field experiments will use a Remotely Operated Vehicle (ROV) and a Phased-Array Doppler Sonar (PADS) system to study the characteristics of the dewatering plumes. The subsequent transport of the material in the dewatering plume will be monitored via shipboard surveys and, potentially, Autonomous Underwater Vehicle (AUV) operations, and these studies will be integrated with near real-time, data assimilating numerical model predictions. The ultimate goal of this project is to develop a field validated, recommend strategy for the release and monitoring of dewatering plumes, to help inform the development of ISA regulations and the planning of industrial operations.

Jan 1, 2017

By Dutton D

In the British coal mining industry, during the last decade, a great deal of environmental monitoring experience was acquired, particularly in the Doncaster Area of the Yorkshire coal- field, which had a long history of spontaneous combustion and gas emission problems. This paper summarises the experience obtained and shows how the introduction and operation of these systems has resulted in improved techniqu- es for fire detection and control. Some of these systems are described in detail with emphasis placed on the uses to which output data are put, and their impact upon management at colliery level. Reference is also made to the problems encountered in the development of such systems and how they were solved. The paper also makes reference to the recent Research and Development work of the NCB's Scientific Department and Mining Res- earch Development Establishment (MRDE), which was directed to the design and application of a range of underground sensors, and so ensured continuing progress in this field. The paper refers briefly to a new comprehensive monitoring unit and an integrated fire detection and data transmitting system which are currently being assessed in the Yorkshire coalfield.

Jan 1, 1983

By M. J. Medd, G. A. Speirs

"This paper describes the simultaneous sinking and equipping of a 4.9 m diameter concrete-lined shaft to a projected depth of 1660 m. The shaft blast design utilizes the full face method using a parallel hole burn cut. Hydraulic drilling and a totally redesigned Cryderman-type mucking unit were integrated into the four deck sinking stage to provide for drilling, mucking, concreting and shaft steel equipping operations. A safety program was tailored and implemented specifically for this shaft sinking project.IntroductionIn July 1988, Falconbridge Limited commenced development of its Thayer Lindsley exploration site located some four km north of Sudbury on Regional Road 80.The first phase of this project was awarded to J .S. Redpath Mining Consultants Limited and the scope of work included the engineering and project management to construct a surface plant capable of supporting a shaft sinking and exploration program for potential future mine development. This initial phase of the project was completed on schedule and under budget on December 23, 1988, and is the subject of an independent paper.In November 1988, J.S. Redpath Limited was awarded the shaft sinking and exploration phase of this project. The scope of work consisted of sinking and equipping a 4.9 m diameter shaft to a depth of 1660 m and carrying out the development and diamond drilling on two levels. This work was scheduled to be completed by November 1991.The T .L. Exploration Project is located toward the eastern end of the south range of the Sudbury basin, north of Sudbury. Figure 1 details the projected mining area and the shaft location on the geological complex. Figure 2 is a section showing the exploration shaft that is located in the Norite. Two levels will be developed from this shaft, on the 1310m and 1588 m levels, to provide access for further geological examination of the ore bodies."

Jan 1, 1991

By M. G. Rylatt, G. M. Popplewell

"Production from Canada's first diamond mine is planned for the last quarter of 1998. The climatic conditions and the variation in kimberlite types to be treated have lead to the development of a compact and flexible processing plant.High kimberlite moisture contents and winter temperatures below -40°C have dictated a process flowsheet with limited in-circuit storage to reduce materials handling difficulties. The latest developments in High Pressure Grinding Roll technology will be used to liberate the valuable diamond, reduce diamond breakage, and increase fines production to reduce the amount of material for down stream processing in the Heavy Medium Separation section.A varying heavy mineral concentrate yield has lead to the development of a final Recovery section that will incorporate Attrition Milling and Wet High Intensity Magnetic Separation for concentrate reduction. The latest developments in diamond X-ray sorting will be used to produce a final diamond concentrate for mechanical sizing, weighing and packing.Fine tailings thickening will utilise Deep Bed Compression type thickeners. This relatively new technology can produce;i) high underflow densities at low flocculant dosage rates, andii) clear overflowswith a smaller thickening area than conventional high-rate thickeners."

Jan 1, 1998

By William H. Baer, George M. Carlton, Blake M. Loring

IT is a well known fact that age-hardening alloys remain in a supersaturated, or partially supersaturated, condition only for limited periods of time at temperatures below the solvus. In order to develop optimum properties by subjecting the quenched alloy to precipitation or age-hardening treatment at a specified temperature, it is necessary that the cooling rate be sufficiently high to maintain the required degree of supersaturation of the solid solution. In practical applications the size and shape of the specimens obviously have considerable influence on the rate of cooling and there is need for more information on the effects of various rates of cooling. Cooling rates of quenched aluminum alloys generally have been established by the type of quenching medium, the temperature of the medium and the dimensions of the specimen.1,2,3 Except for the work of Roth3 little quantitative information is available on the measurement of cooling rates of aluminum alloys and the significance of the influence of various cooling rates upon the mechanical properties. The purpose of the present investigation was to study the use of the Jominy test for aluminum alloys (Table I). EXPERIMENTAL PROCEDURE The material for this investigation consisted of extruded rods 1 ¼ to 1 ½ in. in diam. The chemical compositions were as follows: [ ] The modified L-type Jominy specimen with dimensions shown in Fig I was selected as the most convenient means for obtaining a wide range of cooling rates. The standard Jominy specimen was not satisfactory because its cooling rate was not sufficiently high. The four flat surfaces machined at right angles along the length of the L-type specimen to a depth of 0-015 in. facilitated the hardness measurements. The specimens were machined from the extruded stock with no intermediate forging. New specimens were used for each aging experiment. The specimens were given solution treatments of 2 hr duration at recommended temperatures in a Hoskins furnace (Table 2). The temperature of the furnace was maintained constant to ±3°C. No protective atmosphere was necessary because the thin film of oxide that formed on the surface of the specimens had no effect on the hardness measurements.

Jan 1, 1948

By Shu Xinqian, Zhou Weining, Shan Zhiqiang, Feng Jifu

"Modified calcination conditions on the extraction of rubidium resources from muscovite (KAlz[AlSi301o](OH)2) ore are systematically studied. The impact of various factors on the rubidium leaching rate is also analyzed, including the agent types, roasting time, the mass ratio, roasting temperature, etc. The results indicate that the best agent is a combination of sodium chloride and calcium chloride, its mass ratio ofmuscovite/NaCl/CaClz is 1:0.25:0.25. Calcined at 8500 for 30 minutes, the rubidium leaching rate is up to 90%. The reaction of muscovite ore with the chlorinating agent CaC12 has been studied by TG/DSC, the calcined intermediates are identified by XRD, and the surface morphology before and after leaching is characterized by SEM. Rubidium chloride products can be obtained with a purity of 92% by using t-BAMBP extraction, hydrochloric acid reextraction and purification.IntroductionRubidium is one ofrare alkali metals, which is found in 1981 by German R.W. Bunsen and G.R. Kirchhof. Rubidium includes the following features: atomic number is 37, each atom weight 85, the body-centred cubic lattice, each unit cell has two metal atoms, and the density is 1.532g/cm3. The properties of low melting point (312.46 K) and malleability make rubidium have a strong chemical activity and photoemission. Rubidium provides a main material for manufacturing phototube with a wide range oflight waves, which possess high sensitivity and stability. Efforts are being made to carry out research on rubidium ion gngine, magnetic flux generators and thermoelectric transudcer, etc. Rubidium exists in muscovite ore(KA12[AlSh01o](OH)2 (monoclinic system and hexagonal layered structure) as isomorphism and replace the large radius of the potassium atoms, as well as part of rubidium locate between structure layers. The complex components bring great difficulty in comprehensive recycling."

Jan 1, 2013