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By Roland Trunk, Marcel Imbach, Yves Boissonnas, Jan Vesely

"INTRODUCTION The expansion of the Suez Canal, which runs between the Mediterranean and Red Sea, is at the top of Egypt’s economic agenda. The £8 billion development plan includes a new channel alongside the existing one which will double the number of ships able to pass each day and several tunnels to connect the Sinai peninsula to the main part of Egypt. The Egyptian government ordered three new tunnels under the Suez Canal in the area of Port Said as part of the Canal Region Development Plan. The three tunnels will contribute to the North Sinai expansion, helping to create a vast industrial zone and completing the coastal road extension from Rafah to Nuewiba. Two of these three tunnels will be allocated for roads and the third for railway traffic. A further part of the Suez Canal development mega project are an additional six tunnels in the area of Ismailia and Suez. The focus of this paper is on the two road tunnels in Port Said and will give an overview of the project and the challenges encountered regarding the technical complexity and tight time schedule both in its design and execution. PROJECT OVERVIEW The tunnels will be built in the area of Port Said (see Figure 1) which is the most northern part of the Suez Canal.The road alignment connects the Port Fuad Road in the east bank of the Suez Canal to the Port Said-Ismailia highway in the west bank with a dual carriageway section. Each of the carriageways has two lanes. The bored diameter of the 2.8 km long road tunnels is 13.050 m and will be driven with two Mix-Shield TBMs. The distance between the two tunnel axes is planned with 42.5 m (discussion about a reduction are ongoing). The width of the Suez Canal is around 340 m at upper level and around 170 m at the bottom. During the TBM drive, three main geological layers are expected. Below a depth of around 40 m in a very soft clay layer, a dense to silty sand layer is predicted. Within the sand layer another silty hard clay is expected in different depths with variable thickness. After finishing the excavation of the road tunnels, the same TBM will be used for the railway tunnel. The lowest points of the road tunnels will be located 59 m below the surface (tunnel invert to surface) and only 18 m of ground cover exists between the tunnel crown and the Suez Canal invert. Minimum ground cover over the tunnel crown is approximately nine meters at the tunnel portals."

Jan 1, 2016

By J. Stachurski

Flotation tests were carried out on 6 coal samples of different rank as well as their oxidized samples. A mixture of diesel oil and alcohols was used in these tests. Surface oxidation caused a distinct decrease of the flotation recovery with some improvement in the grade The reduction in the recovery increased with increasing the concentration of the oxidizing agent. The floatability of low rank coals was affected by oxidation to a higher degree than medium and high rank coals. The recovery size curves of oxidized samples mere similar in shape to that of non-oxidized coals.

Jan 1, 1990

By G. Thorsen

An alternative way to the normal practice of precipitation of jarosite, goethite, or hematite for removal of iron from zinc sulphate process liquors/ is to employ the techniques of solvent extraction. The process presented avoids the addition of any external alkali for the extraction of iron by integrating the leaching and solvent extraction steps in a hydrometallurgical zinc plant. By starting the leaching of zinc from the solid zinc calcine material with an organic solution of an acid liquid cation exchanger, the organic phase is loaded with the organic zinc salt from the direct reaction with zinc oxide. The residue from the organic leaching is transferred to a hot acid leach circuit where the remaining zinc oxide and the zinc ferrites will dissolve form¬ing an aqueous sulphate solution of zinc and iron. In the subsequent solvent extraction of iron from this aqueous leach solution, iron is exchanged with zinc from the organic phase. The commercial carboxylic acid Versatic 10 (Shell) is highly efficient for this integrated process of leaching and solvent extraction. The resulting iron-loaded organic phase is heated to 150-200 C in the presence of water whereby the iron will be directly precipitated from the organic phase as iron oxide of high purity and the regenerated organic acid is recycled to the organic leaching step for reloading with zinc.

Jan 1, 1980

ICMM’s vision is ‘a viable mining, minerals and metals industry that is widely recognised as essential for modern living and a key contributor to sustainable development’. The ICMM Sustainable Development Framework provides the basis for achieving this vision by assisting the industry to improve its performance. Two years on from the first SDIMI conference, significant progress has been made in further developing and implementing the Framework. To fulfill their commitment to implement and report performance against the ten sustainable development principles in the Framework, ICMM’s corporate members have committed to report ‘in accordance’ with the GRI 2002 Sustainability Reporting Guidelines and the Mining and Metals Sector Supplement, developed by the GRI and ICMM. While much remains to be done, development of the Supplement and the commitment to reporting mark an important milestone for ICMM and the sector.

Jan 1, 2005

By F. L. Wilke, J. Fabian, D. Oravec

The task of production planning in ore mining is primarily con¬cerned with the removal of ore blocks within planning periods spread over the life of the mining operation. The investigation of this problem in the past resulted in the introduction of computer based optimizing techniques for production scheduling and se¬quencing. Although these techniques succeed in computing an "optimal" mine output for one planning period, they usually fail in composing a practical and feasible mine plan over the periods in concern. This paper describes conventional production planning based on operations research and the capabilities of a knowledge-based approach. An example of a planning system for the Slovak under¬ground iron ore mine Nizna Slana will be presented. By combina¬tion of these two techniques this system should improve the qual¬ity of planning procedures.

Jan 1, 1996

By S. P. Hansen

Gravity sedimentation is one of the most widely used processes for separating solids from liquids whether it be for ore and mineral processing or for treating municipal sewage or industrial wastes. Investment in sedimentation equipment can represent a significant portion of the total capital costs associated with a processing or treatment facility. In spite of the importance of sedimentation, little attention has been devoted in recent years to improving this equipment by applying the basic principles involved in sedimentation. In the water and waste treatment field, design criteria established one half-century ago is still the accepted standard and in reflection of this lack of progress, sedimentation and thickening equipment has remained virtually unchanged. The primary purpose of this paper is to present and describe a new innovation in gravity sedimentation which has been applied to water and wastewater treatment and could definitely have application in the field of ore and mineral classification. A secondary object is to introduce the mixed media filter which has been widely used to treat municipal drinking supplies, industrial process water and to provide tertiary treatment of sewage and industrial wastes. The tube-type clarifier was developed primarily to be applied in the field of water and waste treatment where it was found that it could be used to considerably reduce the size and cost of clarification facilities. A logical extension of the tube clarifier would be to the area of minerals classification, ore separation, and for treating waste water associated with these activities. In water treatment practice, most clarification processes are followed by a filtration step to provide further polishing of the water prior to use. This paper will also discuss the mixed media filter which is graded from coarse to fine in the direction of filtration and is capable of operating at high filtration rates and with greater applied suspended solids loading than other filter designs while providing a high qualify filtrate.

Jan 1, 1970

By J. J. Schwoebel, M. J. Mavor

Rapid coal extraction techniques in gassy mines may strain a ventilation system if a degasification approach is not utilized. Design of mine ventilation systems requires estimates of gas emission rates from unmined coal into the existing mine workings. A degasification system for a specific property can be properly engineered to improve mining economics if the proper geologic and reservoir information is collected. This paper describes methods to determine the degasification rates for horizontal boreholes and vertical (stimulated and unstimulated) wells and the rate of gas emissions into the mine workings. The methodology is demonstrated by a specific example. Horizontal boreholes drilled in advance of mining are demonstrated to be the most effective means of coal seam degasification and reduction of gas emissions into mine workings. The significance of the paper is that few published methods for these estimates are available

Jan 1, 1991

Africa is rich in natural resources, much of which remain untapped. Despite that, international mining companies have largely stayed away from the continent due to political instability in many countries, lack of infrastructure and the inability to gain control of mineral deposits. Today, optimism is growing concerning African mining. Many of its nations are moving toward privatization of their mining industries. They see it as a way to improve the lives of their populations and become politically stronger. Ministers from 22 African nations were Denver, CO in June for the World Bank's Multilateral Investment Guarantee Agency's Fourth Annual African Mining Investment Symposium. The three-day symposium drew more than 400 mining executives and government representatives. Foreign mining investment in Africa is on the increase. In 1996, international mining companies spent about $418 million on exploration. That is more than double the $190 million spent in 1994. Mining executives say the mining climate in Africa is improving because countries are privatizing the industry and rewriting mining laws that encourage natural resource development. They estimate that private mining firms now control about 80% of mining today. Mine development will help lift the living standards for Africans, the ministers said. The average income for ordinary Africans is about $500 a year. If this new mining boom continues, citizens of nearly all African nations will reap the benefits of better infrastructure and government services, as well as more higher paying jobs, the ministers said. They also issued a word of caution to mining companies attempting to join in the African boom. Concerns are being raised about the treatment of villagers and the environment. In the past, foreign companies would "behave about like colonial masters," said Gerald Ssendaula, natural resource minister for Uganda. Africa is in a different position now, he said. "Now we are solving our own problems." Mining companies must respect local communities or risk creating unrest that will threaten fragile new governments, said Akolang Tombale, chief geologist for Botswana. On the other hand, he said villagers must accept that mining development will benefit them. "They feel these are their natural resources. There must be a mutual interaction between the companies and the people."

Jan 1, 1997

By Omar A. Muhtadi

8.1 INTRODUCTION Several methods currently exist by which gold may be recovered from a pregnant leach liquor. Two of these methods are discussed in this chapter, the Merrill-Crowe (zinc cementation) process and the carbon adsorption process. These two methods represent the most frequently used techniques for gold extraction and are, -in fact, used almost exclusively in U.S. heap leaching operations. Because of the efficiency and ease of use of these two methods, it is extremely likely they will continue to be quite prevalent within the gold mining industry in years to come. The remainder of this chapter includes information on the history of the two processes, descriptions of the actual processes, criteria to consider in selecting a recovery process, and commercial design and construction considerations for both of the gold recovery methods. As with other chapters in this book, some fairly technical information is presented for the benefit of those readers needing a greater level of detail. However, the overall intent of the chapter is to provide an overview of the processes likely to be used in gold extraction, thus giving the reader a firm basis for more technical research into the topic, should this be needed. 8.1.1 History of Zinc Cementation During the late 18901s, zinc cementation was introduced for the precipitation of gold and silver from cyanide solutions. This occurred at about the same time as the introduction of the cyanidation process, the history of which is recapped in Chapter 1. The initial cementation process involved introduction of a gold-bearing cyanide solution onto a bed of zinc shavings. It proved to be quite inefficient because the reaction rate was very slow. The zinc quickly became "passive", inhibiting further gold deposition. Shortly after this first introduction, zinc precipitation was improved by adding a lead salt (usually lead nitrate) to the zinc. This allowed a zinc-lead couple to form on the surface of the shavings, eliminating passivation of zinc surfaces and thereby allowing continued deposition of gold. Further improvements were shortly forthcoming. The first of these involved the use of zinc dust rather than zinc shavings. This provided a much

Jan 1, 1988

By C. Haycocks

The evolution of longwall mining is briefly traced from its inception in England in the 1620's. In the beginning this method recovered 90% of coal with roof closure controlled by packs and walls. Mechanization began with kerf cutting, crude face conveyors, and improved face support. Full face mining was accompanied by the introduction of self-advancing hydraulic supports. U.S. longwalls evolved a retreating system to recover blocks of coal outlined by room and pillar panels. Computer control combined with the most modern technology has greatly increased productivity. Past trends are used to predict future technological directions.

Jan 1, 1997

By Carlon C. Chambers

INTRODUCTION Manufacturer sponsored research over the past three years has proven the suitability of styrene-butadiene/ asphalt membranes in many waste disposal seepage control applications for the mining industry in general and uranium mining and milling in particular. The class of membranes that have been tested are SBR/asphalt blends containing up to 68 weight percent asphalt, the balance being elastomeric polymers, fillers and phase compatibility promoters. These membranes are classified as thermoplastic, elastomeric materials and can be hot spray applied to any moderately dry substrate at 177°C (350°F), and placed in service within one hour of application. The properties of this membrane that make it suitable for use as an engineering_ material in these applications are discussed. These properties include chemical resistance, bacterial resistance, UV light resistance, permeability, stress/strain characteristics and bonding data. The favorable economics of the system are also discussed. The preliminary raw test data on the above properties were reported in a previous paper, (Chambers, 1980) and most will not be repeated here. Instead, this report considers the original data in relation to subsequent data and concentrates on interpretation of the trends for engineering purposes. However, several of the pictures contained in the original paper are reproduced in this report for illustration purposes. BACKGROUND Asphalt alone has a long history of use as a water-stop material. Its limitations of becoming brittle when cold and soft when hot, however, are well recognized. The service temperature for common grades of asphalt is usually in the 4° to 49°C (40° to 120° F) range. Modifications to the base asphalt can generally improve its performance at the high end of the temperature range by raising its softening point, but only the addition of one class of modifiers, elastomeric polymers, improves low temperature flexibility as well and also adds resilience. Both of these properties are of extreme importance if the waterstop material is to maintain its integrity when used on substrates which are unstable, non-cohesive, discontinuous or have significant expansion/constraction coefficients. Although there are many elastomeric polymers which can be used with

Jan 1, 1980

By S. M. Robinson

Wollastonite is recognized as one of the most unique, non-metallic minerals in the world. Its history for use in industrial applications is recent compared to other minerals, however, its distinctive physical properties, such as acicular particle shape, and alkaline pH creates incorporation possibilities ranging from bowling balls to automotive fascia, from ceramic tiles to automotive brakes, and from thermal insulation board to industrial and trade sale coatings. Its future use will be impacted by the exploitation of deposits which will ensure maintenance of the acicularity and purity of this naturally occurring mineral. Additionally, closely held surface treatment technology will open up additional niches requiring highly engineered performance.

Jan 1, 1995

By C. A. Rowland

Wet grinding rod mills have been used for 50 years to grind ores and to make specification sand. The application of wet grinding rod mills is well understood. Until recently, there have been very few installations of dry grinding rod mills. The basic principles learned from wet grinding rod mills that were used in the application of dry grinding rod mills are 1. It is possible to extrapolate the performance of 5' and 6' diameter wet grinding rod mills into larger diameter rod mills with the larger mills performing as predicted. Wet grinding rod mills as large as 14' diameter (inside shell) by 20' long using 19.5' long rods are in use operating satisfactorily. 2. Wet grinding rod mills generally grind more efficiently when the fines are left in the mill feed than when the fines are removed from the feed. 3. Wet grinding rod mills produce little tramp oversize and generally can be operated in open circuit except when very close control on the top size in the product is required. When operated in closed circuit, the circulating load is normally less than 100%. 4. The power required for the desired grind can be accurately determined from the work indices obtained from rod mill grindability tests on the material to be ground. Where required it is necessary to, apply inefficiency factors for oversize feed and for larger or smaller than normal- ratios of reduction. Recent applications for rod mills have developed where it is required that dry grinding be used. These recent applications cover the grinding of 1. Lead sinter, lead slag and limestone. 2. Iron ore. 3. Silica for making glass sand. 4. Cement clinker. 5. Coke.

Jan 1, 1968

By Thomas Jancic

Two of the open-pit, copper-molybdenum mining operations of Duval Corporation are located in the foothills of the Sierrita Mountains approximately 30 miles southwest of Tucson, Arizona. In March 1959, mining from a moderate sized porphyry deposit known as the "Esperanza orebody" was begun at a rate of 10,000 tons of ore per day. Some five years later, a sizeable group of mineral claims west of Esperanza became available to Duval. Earlier exploration and development drilling in this area by others indicated an orebody of greater size but lower tenor than that of Esperanza. A drilling program conducted by Duval not only verified the results of the prior drilling but in addition, revealed a continuation of the mineralization to the south and east. Thus was developed the Sierrita orebody. Open pit design delineated 414 million tons of ore containing an average copper content of 0.35 percent and a molybdenum content of 0.036 percent. In April 1966, the office of Emergency Planning authorized General Services Administration to undertake a program under the Defense Production Act to en¬courage additional domestic production of copper in the interest of national defense. Duval's Sierrita Project was brought to GSA's attention in May 1966 on November 28, 1967, an agreement providing for the development of the Sierrita Property was consummated with GSA. In March 1970, the first copper-molybdenum concentrates were produced in the 72,000 tons-per-day concentrator. Pre-production stripping exceeded the scheduled 105 million tons despite the comparatively short lead time available to equip the mine, build the mine plant facilities, and staff the technical, supervisory, and labor forces. Shortly before the first concentrates were produced, plans were being formulated for a program to increase processing capacity by approximately 15 percent, which entailed increasing overall mining capacity by approximately 50,000 tons per day. This program is scheduled for completion early in 1971.

Jan 1, 1971

By H. Sahay

The current Canadian coal production is approximately 57x106 tonnes per annum of which some 25 million tonnes is exported. Two thirds of the Canadian output is classified as thermal and one third as coking or metallurgical coal. The Canadian coal industry, like the industries in some other industrialized nations, has gone through a cycle of ups and downs. The current world vide recession and stable oil prices have somewhat dampened the plans for a further growth of this industry - albeit temporarily. No new mines are expected to be developed within the next few years. However the production is projected to increase to 60x106 tonnes in 1985 increasing to an estimated 75 to 80x106 tonnes by 1995. The Canadian mines are highly mechanized and are willing to employ the modern technology to maintain its competitive position in the world's coal market. This paper reviews the recent technical developments which continue to improve resource recovery and productivity.

Jan 1, 1986

By J. Zhai, Z. Yin

"The electrokinetic and flotation behaviors of ilmenite using lead ions as the activator and sodium oleate as the collector were studied. The results of microflotation show that the flotability of ilmenite can be improved by lead ions obviously. The isoelectric point of ilmenite increases from 5.32 to 7.7 after the addition of lead ions because of the adsorption of Pb2+ and Pb(OH)+. The results of zeta potential measurements and the collector adsorption density calculation show that the adsorption of sodium oleate on the ilmenite surface via chemisorptions in addition to electrostatic interactions. Besides, the adsorption density calculation results show that as the addition of lead ions as the activator, the adsorption amounts of collector are greater than those without activation which is in aggrement with the flotation behaviors. INTRODUCTION Ilmenite, as an oxide mineral of formula FeTiO3, is usually used as the main resource of the extraction of titanium (Bulatovic and Wyslouzil, 1999). There are many researches showing that the conventional methods, such as gravity separation, magnetic separation and flotation, do not work efficiently as expected (Mehdilo et al., 2015; Zhu et al., 2011). Nowadays, to produce ilmenite concentration feasibly and efficiently, these separation methods above are combined for a reason that the raw ilmenite ores are characteristic of poor, fine and complicated. Moreover, surface modification, such as surface dissolution method, microwave irradiation and oxidation roasting, is applied to improve the flotability of ilmenite currently (Welham and Llewellyn, 1998; Zhang and Ostrovski, 2002). Generally, fatty acid salts are used as the collector for the flotation of oxide minerals and sodium oleate is usually used as the collector for the flotation of imenite ores (Fuerstenau and Pradip, 2005). The mechanism, such as individual ion electrostatic adsorption, chemical adsorption, ion–molecule dimeric complex adsorption, and the coadsorption of ion and molecule, have not been discussed systematically using sodium oleate as the collector in the flotation of ilmenite (Somasundaran, 1983). Under the activation circumstance using the lead ion as the activator and sodium oleate as the collector, the interaction mechanism seems to be still unclear. In the present study, the interaction mechanism between ilmenite and sodium oleate using lead ion as the activator are studied by microflotation, zeta potential measurements and adsorption density calculation. EXPERIMENTAL Materials and reagents Pure ilmenite minerals were obtained from Panzhihua, Sichuan province, China. The minerals were ground in a porcelain mill with an agate ball. Following that, the prosucts were sieved, and the samples of -0.074+0.038 mm size fraction were used for the microflotation experiments. The results of XRF show that the content of titanium element is 30.58%, showing that the purity of ilmenite is above 90%. On the basis of the results of XRF, it is determined that the purity of ilmenite is very high and meets the needs of microflotation"

Jan 1, 2017

By H. M. Breza

Utilization of Bucket Wheel Excavators and Overland Conveyor Systems to remove overburden provides increased productivity and flexibility to a surface mining operation. The utilization of such a system at the Texasgulf Inc. Aurora, North Carolina Mine has significantly improved the overall productivity of the mining operation. System flexibility is evidenced by adaptation to operation requirements such as mining area moves, movement of excavated overburden to designated sites, selective handling of overburden, spoil placement contouring, and providing an environmentally sound and safe operation. System productivity is evidenced by actual case studies relating to overall production, excavation rates, and cost effectiveness.

Jan 1, 1993

By Zainab Nasrullah, MontanaFrank Agyemang, Mehran Sadat, Richard LaDouceur

Rare earth elements (REEs) are valuable for various modern technological applications, including metallurgy, machine building, radio electronics, instrument engineering, nuclear engineering, and manufacturing. The extraction and separa-tion of rare earth elements (REEs) from their complex ores is challenging due to their distinct physical and chemical properties, contributing to their market scarcity. At present, REE recovery utilizes traditional pyro- or hydrometallurgi-cal processes. The overall process in the recovery and sepa-ration of individual elements from complex REE systems suffers from high energy demands and the use of many haz-ardous chemicals that negatively impact the environment. With the growing trend toward a circular economy aim-ing to balance sustainability, efficiency, and environmental impacts, this research is focused on using deep eutectic sol-vents (DESs): a combination of a quaternary salt: Choline Chloride and five organic acids: Oxalic Acid, Urea, and Ethylene Glycol, Lactic acid and Glycerol for the selective leaching of REEs from their complex ore which is proven to be green, selective, non-toxic, biodegradable, and cheap. The effects of different DESs and leaching time on the REE leaching efficiency were determined, and the optimum DES media were found to be Oxaline and Lactic Acid at which a leaching efficiency of 25% and 15% was achieved at 80°C respectively for cerium.

Feb 1, 2025

By Thomas A. Wilson

Mountain Pass, California is located 96 km southwest of Las Vegas, Nevada, and has an exposed surface orebody within view of Interstate Highway 15. Mineral prospecting in this region dates back to about 1860 followed by the discovery and subsequent mining (1870-1895) of silver bearing veins on the north slope of nearby Clark Mountain. In contrast to the four lane divided interstate highway of today, all supplies needed for mining during this early history were transported by wagons from San Bernardino which is 320 km west. Many small lead mines were active in the area during 1917-20, and a small gold mine operated in 1941-42 within 100 m of the orebody presently being worked. In 1949 two prospectors searching for uranium with a Geiger counter discovered a radioactive vein outcrop at Mountain Pass. Further investigation revealed the presence of a large amount of a light-brown, heavy mineral to a depth of about 2 m. A sample of this unidentified mineral was submitted to the Boulder City, Nevada, U.S. Bureau of Mines where a spectroscope examination shoved high level rare earth oxides, carbon dioxide, and fluorine. These results indicated the mineral was bastnasite.

Jan 1, 1982

By R. R. Rollins

Field data combined with theoretical derivations were used to design a surface mining operation using explosive casting. Calculated casting results varied from 44 to 65% depending on bench height. This model was then applied to field tests at an eastern, contour, coal stripping operation. Results from five experimental casting shots are summarized and compared to conventional mining methods. The overburden material removed by casting ranged from 35 to 65% with an average of 50%. Fragmentation was improved and it was demonstrated that this procedure is economically attractive with a resultant cost savings of $.59/m3 or $5.93/t of clean coal.

Jan 1, 1987