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By S. Lin

A new hydrogen production process, named the HyPr-RING, has been proposed. Fundamental concept of the HyPr-RING is integration of water carbon reaction, water-gas shift reaction and CO2 absorbing reaction in a single reactor. Firstly, thermodynamic analysis was done to judge the possibility to realize the process. It was found that high pressure and temperature condition, such as 20 MPa and 1000 K, is required to promote this integrated reaction. Next, experimental verification of the new process was done under the high pressure and temperature reaction conditions. As the results, integration of above three reactions in a single reactor can be done successfully and produced a large amount of hydrogen as estimated by thermodynamic analysis. Experiments showed that organic materials including coal, heavy oil, biomass, plastics can be used in this process. In the gaseous phase, no pollutants such asH2S, SO2, COS are detected so that gas cleanup system is not required for power generation when this process is used. Finally, a process design was made to estimate process efficiency. Theoretically, 1 mole of carbon can generate 2 moles of hydrogen and cold gas efficiency of this process estimated as more than 80 per cent. The process potentially reduces hydrogen production cost compared with the conventional hydrogen production methods. Keywords: Hydrogen, Fossil fuel, Energy, Process, Supercritical water

Jan 1, 2001

By Brian A. Ferguson, Raynald O. Vezina, Marielle Gaudet, Raoul R. Boissonneault

"Kiena has been committed to developing a fresh management and employee relations approach since the commencement of production in 1981. The functional organizational structure encourages joint participation and commitment on the part of all employees to common goals in safety and production. The results over the last four years have been extraordinary. Kiena won the John T. Ryan Canada Trophy for 1983 for its safety record and has experienced a steadily increasing productivity through the application of new mining equipment and technology in the hands of a well-trained and motivated team of employees.This paper serves to highlight the fact that productivity, safetyand technical innovation are closely linked to employee participationand involvement which are likely to be the key to theCanadian mining industry's survival in the years ahead.This presentation follows up on an earlier unpublished paper, given at the 84th Annual Meeting of CIM in Quebec City in April, 1982, which discussed the philosophy and the planning which took place before implementation of the management and employee relations system at Kiena. This present paper reviews and expands on material given in the earlier work. IntroductionThe mining industry, which has always been considered as rather conservative in its approach, has experienced with some regularity, cyclical periods related to metal prices. These cycles, previously foreseeable to some extent have become less coherent over recent years during which time the industry has had to face fierce international competition. The issue to productivity is without doubt the major concern of the mining industry in Canada today and it represents the greatest challenge facing us during the present decade. Developments that have been made in mining technology over the precious two decades have failed to completely produce the significant advancements in higher over-all productivity that were expected."

Jan 1, 1987

By Qi Wang, Zengzhu Kang, Jianguo Liu, Guanglei Liu

"Due to the increase of automotive vehicles, available parking spaces become a new type of limited resource in central cities of China, especially in those old districts without visionary urban planning. Additional mechanical parking in underground space is an efficient solution to provide parking spaces under the situation where the urban space is constrained. Shichahai district is an old protected zone in Beijing which is close to the Forbidden City and there are many Hutong (alleyway) and Quadrangles (courtyard house). No spaces are available for car parking on the ground and all vehicles are parking in Hutong without order currently. The local government plan to do renovation work for this district and improve the residential environment. Several innovative solutions are studied including parking in deep shafts, parking under existing buildings by under-pinned method, parking under buildings by covered excavation method, parking under roads built together with utility tunnel etc. 5000 difference types underground parking spaces are planned to be constructed in the following three years. Project examples are also introduced in this paper. INTRODUCTIONCar parking resources are very limited in central cities, especially in old districts without planning for increasing automotive vehicle volume. Traffic get worse when cars park on the side of the roads or move slowly to find parking spaces. Investigation shows the normal (parking space/ automotive vehicle volume) ratio is about 1.2 in most big cities such as New York, Tokyo and Hong Kong, while this ratio is only 0.5 in Beijing. One solution is to move cars out of central cities. But there are still huge parking requirements for the citizens living in central cities. Shichahai district is an historic protected zone in Beijing which is close to the Forbidden City and there are many Hutong and Quadrangles (refer to Figure 1 for project location). No spaces are available for car parking on ground and all vehicles are parked in Hutong without order currently. The local government had a plan to do renovation work of this district and improve the residence environment. 5000 different types of underground parking spaces are planned to be constructed in the following three years. One project designed and to be constructed by Zhongyan Technology will be introduced in this paper. Other innovative solutions will be introduced briefly as well."

Jan 1, 2017

With the ever increasing problems of narrowing profit margins, and increased liability, a solution/option to SEE members is needed. It is essential that all members understand the benefits of utilizing explosives in combination with other methods of achieving the required result on difficult rock or concrete removal projects.

Jan 1, 1995

By Donald Leroux, Jean-François Wilhelmy, Ahmed Bouajila

"A young private R & D organization, COREM celebrated its 10th anniversary in 2009. Managed by a consortium of nine mining and metallurgical companies, COREM has the mandate of increasing the competitiveness of its member companies through the development and transfer of mineral processing innovations. Typical technologies developed by COREM include alternative mineral processing techniques, novel operating strategies, innovative sensors and process simulation software. Many of them were developed in partnership with universities and selected research organizations.Because the COREM membership base is broad (from ferrous to base, to precious metal industries), its R & D program must deliver technologies with applications within a wide spectrum of mineral processes. Comminution, physical (gravity and magnetic) separation, flotation, cyanidation, pelletizing and thermal processes are the main topics of the R & D program. A number of new technologies have been developed and transferred to the plants of member companies. These examples of transferable technologies demonstrate the capability of COREM to impact the bottom-line of its member companies.INTRODUCTIONCOREM is a private mineral-processing R & D organization that operates from its own laboratories and pilot-plant with its own staff of professionals and technicians (about 95 persons). It is managed and financially supported by a consortium of nine mining and metallurgical companies and three provincial and federal ministries. The very ‘down-to-earth’ mission statement of COREM is to increase the competitiveness of the mineral processing plants of its members. The eighteen plants upon which the COREM technology development program is currently based can be found in Québec, Newfoundland and Labrador, New Brunswick, the Netherlands and Botswana."

Jan 1, 2010

By Steve Kral

Commodity price down cycles are a fact of life in the mining industry. And companies pre-pare for them as best they can. Evenso, operations are still curtailed or closed during those cycles, profits shrink, layoffs are inevitable and many companies do not survive. However, one of the few good things that occurs during down cycles is the new, innovative exploration, mining and processing technologies that come about during hard times. To survive the lean times, the mining industry turns to improved technology to decrease costs and hold the bottom line. And, because mining is a cyclical business, each down cycle brings about technology improvements that carry over into the good times.

Jan 1, 2004

By Rudi Toba

Several areas at the DOZ haulage were observed for the crusher’s location. Initially the new crusher designed position was west of the crusher 1, but due to concerns of the mine crack zone (deep MLZ) the crusher position moved to the south. The new crusher location is situated in a diorite rock massive between 3053 – 3079 levels, with the overall excavation of 2500 cum and dimension of 14m long, 14 m wide and 14 m high. Main Crusher chamber itself excavated by development jumbo in three lifts. Development of access to the bottom crusher was developing the same time as chambering the top crusher. The pocket of the crusher mined with vertical crater retreat system which is initiated in one time after middle slot raise. Collaboration between production and perimeter blast holes to be obtaining in control the actual cuts as per the design shape.

Jan 1, 2007

By G. Goellner

The thick alluvial sand and gravel deposits along the base of the San Gabriel mountain range in Southern California area have been mined for construction aggregates for over 100 years. Encroachment of high-density urban populations in this area has led to concentrated mining in a handful of open pit mines with single production faces reaching up to 55 m (175 ft) in height, and long transportation distances from the pit to the processing plant. Aggregate producers have responded to these challenges by developing innovative mining systems which enable low-cost, full-face mining of the alluvial material, and low cost delivery of this material to the plant.

Jan 1, 2004

By Axel Nitschke, Josef Arnold

Bochum’s Underground Lot 306 was characterised by a confined site and unique tunnelling methods. A highly mechanized construction concept was developed to achieve high progress rates. Bespoke backup systems for muck disposal and material supply were used. For the first time in suburban tunnelling, wet shotcrete, batched onsite, was applied. A three-storey underground car park had to be undermined with only1.5 m of overburden and had to be lifted several times by “compensation grout in.” An existing operational two-lane metro tunnel was enlarged without any major impact on train operation.

Jan 1, 2005

By Thomas Marcher

Stanford Linear Accelerator Center (SLAC) is located in Menlo Park, CA. In order to allow for enhanced experiments, the current facilities required expansion. Tunnels were excavated through very weak sedimentary rock interspersed with uncemented zones (Ladera Sandstone) employing the principles of the NATM. The overburden var-ied from 10 to 80 feet. The paper addresses the characterization of Ladera Sandstone that can exhibit the properties of dense sand and weak rock. The paper focuses on the challenges that were encountered during the NATM initial support design and the construction phase including the geotechnical instrumentation, monitoring and design verification process in particular the excavation of the junction between access tunnel and the FEH cavern (49 ft wide by 32 ft high).

By Rick Moignard

Relationships between Information Technology providers and their clients are often segmented according to job specific tasks. As a consequence, technology providers tend to focus on automating repetition and complexity, resulting in software that improves individual productivity while failing to address the interdependency of mining functions. For this reason, technology vendors like Gemcom are following partnership approaches with their clients, engaging corporate and operational stakeholders to better understand mining business objectives. This presentation examines some of the approaches that help foster the development of solutions that leverage the information produced during mine operations to improve downstream process control and tactical decision support.

May 1, 2006

By H. A. Oliveira, A. Azevedo

Physical and chemical characterization and solid/liquid separation of turbid waters from a river affected by an iron tailing rupture disaster (Gualaxo do Norte River, Brazil) were studied at bench scale. Parameters such as turbidity, pH, surface tension, electrical conductivity, total suspended solids (TSS), particle size distribution (micro- and nanoparticles), and zeta potential were analyzed from samples collected at three different river depths. The results in all samples showed the presence of micro- and nanoparticles, ranging in diameters from 100 nm to 200 μm. Best results for flocculation and settling were obtained at pH 7.5, through an innovative combination of eco-friendly reagents: (i) ferric hydroxide precipitates (10 mg L−1 Fe3+) to sweep (enmesh) the dispersed solids and (ii) gelatinized starch (5 mg L−1 ) to form large flocs. The results showed removals between 90 and 100% of total suspended solids (micro- and nanoparticles), resulting in clear water with residual turbidity < 7 NTU. It is believed that this innovative alternative has a high potential for flocculating and treating the turbid water at Gualaxo do Norte River, assisting the water treatment stations.

By H. A. Oliveira, A. Azevedo

Physical and chemical characterization and solid/liquid separation of turbid waters from a river affected by an iron tailing rupture disaster (Gualaxo do Norte River, Brazil) were studied at bench scale. Parameters such as turbidity, pH, surface tension, electrical conductivity, total suspended solids (TSS), particle size distribution (micro- and nanoparticles), and zeta potential were analyzed from samples collected at three different river depths. The results in all samples showed the presence of micro- and nanoparticles, ranging in diameters from 100 nm to 200 μm. Best results for flocculation and settling were obtained at pH 7.5, through an innovative combination of eco-friendly reagents: (i) ferric hydroxide precipitates (10 mg L−1 Fe3+) to sweep (enmesh) the dispersed solids and (ii) gelatinized starch (5 mg L−1 ) to form large flocs. The results showed removals between 90 and 100% of total suspended solids (micro- and nanoparticles), resulting in clear water with residual turbidity < 7 NTU. It is believed that this innovative alternative has a high potential for flocculating and treating the turbid water at Gualaxo do Norte River, assisting the water treatment stations.

By G. C. Smith

Process control applications in the minerals processing industry have grown extensively over the years due to the many benefits derived, both financially and operation-wise. Although control theory is widely known, conventional control does not address many of the problems posed by minerals processing circuits. Some of these problems include interactions between process units, large dead times, few and sometimes unreliable measurements of process variables, non-linear systems, disturbances entering the process, processes with varying dynamics, and many more. For the past 26 years Mintek has been active in the field of providing specific, customized solutions for the minerals processing industry. This paper focuses specifically on applications in milling and flotation control. The underlying control principles have been applied to a wide range of other processes including submerged arc furnaces. Advanced control application is implemented on a common advanced control platform, called the PlantStar. Much innovation has been brought to the fore in terms of adapting theoretical techniques and developing new methods to resolve specific milling and flotation circuit issues by using process control. The general approach adopted by Mintek when implementing advanced control is to enforce stabilization of the process as a solid foundation for optimization strategies to be built upon. In doing this, a robust control solution is presented, and the end result is flow and level stability, better product quality regulation, increase in throughput and a stable feed to downstream processes. The MillStar advanced milling control system ensures that the milling circuit is at all times easy to operate while achieving optimum product quality and throughput. Stabilization should include product size regulation and sump level control. Another important aspect of stabilization control is the handling of milling circuit constraints without introducing cyclical behaviour and with minimal disturbance to the final product quality. Process constraints may include factors such as process water limitations, cyclone feed density, and cyclone underflow angle. An optimization strategy should be developed to increase the mill throughput without affecting product quality or introducing mill overloads. The relationship between solids feed and power draw is examined and manipulated for optimization. The interactive nature of flotation circuits and the presence of recirculating streams tend to make satisfactory control almost impossible with conventional techniques such as PI (Proportional plus Integral) or PID (Proportional, Integral and Derivative) control. The FloatStar Level Stabilizer simultaneously considers all the flotation levels in a circuit by use of a multivariable algorithm, and takes compensating action in anticipation of disturbances. The FloatStar Flow Optimizer is an optimization strategy that controls the concentrate flow rate between various sections of a flotation circuit (e.g. Rougher ?Cleaner; Cleaner ?Recleaner). By controlling the concentrate flow between the sections, the mass pull, circulating loads and residence times of the circuit can be stabilized, thereby enhancing the performance of the flotation process. Optimizing grade and recovery are coupled with the dynamic optimization of circulating flows. The FloatStar Grade-Recovery Optimizer will maximize the grade in a section, whilst ensuring that recovery or any other process specific limits remain within predefined limits. With successful applications on several milling and flotation plants worldwide processing amongst others PGMs, gold, copper and nickel, Mintek has shown that it is a leader in milling and flotation control innovation

Jan 1, 2004

By B. J. Schat, A. W. O. Bots, O. S. Langhorst

Amsterdam City Council is building a new metro line, the North–South Line. The line passes under Amsterdam Central Station (a listed building) about 18m below street level. The retaining wall that has to be built underneath the existing building is an innovative construction consisting of two rows of steel piles interspersed with a solid mass of overlapping jet grout columns: a composite ‘sandwich’ wall. This paper gives an overview of the approach taken to designing (computational models) and building the retaining wall. Special attention is paid to the observational method used for the construction of the jet grout columns.

Jan 1, 2007

By Tracy Brettmann, Will Bohlen

An innovative retaining wall design consisting of tangent drilled shafts with supplementary seal piles was used to limit continuing bank erosion along the Brazos River in Southeast Texas. The riverbank erosion had progressed to where it was threatening the stability of both the bridge abutment and corresponding approach embankment of the heavily travelled Highway 99 bridge at this location. A tangent pile design was selected because it was both much faster to install and more cost effective than a secant pile system. The design included both 5.5-ft and 10-ft diameter shafts with depths up to 130-ft and comprised both anchored and cantilevered sections. Supplementary seal shafts were also installed between the structural tangent drilled shafts to help plug any gaps between the tangent shafts. The plumbness and diameter of the shafts were tested using a sonic caliper to make sure the shafts were installed within the specified tolerance. The initial design had to be revised when a record flood from Hurricane Harvey impacted the site during construction. Introduction The Fort Bend Grand Parkway Toll Road Authority (Owner) needed to protect the north bridge abutment with a retaining wall system due to rapidly eroding conditions of the Brazos River banks within the 300- feet-right-of-way of the State Highway 99 Jodie Stavinoha Bridge. The extent of the local scour and erosion along the north bank of the Brazos River has caused concern for the structural integrity of the bridge. The magnitude of the erosion along the north bank at the location of the bridge has been measured at about 120 feet over three recent hydrologic flood events locally referred to as Memorial Day 2015, Memorial Day 2016, and Tax Day 2016. During construction, a new record flood level occurred due to Hurricane Harvey in August of 2017 that resulted in a portion of the retaining wall needing to be redesigned due to even more erosion occurring. The Brazos River is an actively eroding and meandering alluvial river plain that naturally meanders and migrates over time. The processes of bank erosion and meander migration were ongoing before the bridge was constructed and will continue in the future. These recurring major flood events, however, rapidly increased the rate of erosion in just a few years. Background. Due to the need to protect the bridge as soon as possible, the Owner selected a project team consisting of the designer, general contractor and specialty deep foundation contractor prior to final design to work together in developing a cost-effective design that could be implemented rapidly. The project team initially considered both a secant pile and tangent pile retaining wall system using drilled shafts. After reviewing various alternative designs, a tangent pile wall with seal piles was selected based on both cost effectiveness and speed of installation. The tangent pile with seal pile option was approximately 20 percent lower in cost and 50 percent faster to install.

Jan 1, 2018

By Renwick MT

Two innovative ground reinforcement products have been developed for use in the mining industry. One of these products is a high strength polyethylene (HOPE) bar for use as a rib bolt in underground coal mining and as a corrosion proof tendon in open pit mines. The other product is a cable bolt (Ultrastrand) which demonstrates enhanced load transfer and is available in continuous lengths. Ultrastrand&apos;s exceptional in- situ performance and versatility makes it ideal for mechanised installation in both underground and surface mining operations. Details of these products are presented and results from labortaory and field trials are discussed.

Jan 1, 1992

By S. C. Tadolini

Roof support systems have evolved from standing posts and timbers to a generation termed ?big nails? where steel bars are inserted into boreholes and anchored with expansion shells and/or resin cartridges. These systems have been effective but are limited to mining height. Additionally, the properties of steel do not resists shear forces or have the flexibility being required in difficult ground conditions. The next generation of roof support systems is coupling the best parts of the ?big nail? and resin grouted cable bolt systems. This paper will present the advanced technical solutions of the next generation of cable systems that includes an indented high-capacity PC-strand used with a variety of fixtures. Case histories of support applications will be presented.

Jan 1, 2012

By Thomas M. Barczak

With the development of the shield support, the primary requirement for successful ground control in longwall mining is to provide stable gate road and bleeder entries. Wood cribbing has been the dominant form of secondary support. However, the cost and limited availability of timber, along with the poor performance of softwood crib supports, has forced western U.S. mines to explore the utilization of other support systems. The recent success of cable bolts has engendered much interest from western operators. Several innovative freestanding support systems have been developed recently including: (1) "The Can"&apos; support by Burrell Mining Products International, Inc., (2) Hercules and Link-N-Lock wood cribs and Propsetter by Strata Products (USA) Inc., (3) Variable Yielding Crib and Power Crib supports by Mountainland Support Systems, (4) the Confined Core Crib developed by Southern Utah Fuels Corporation; and (5) the MEGA prop by MBK Hydraulik. This paper assesses design considerations and compares the performance and application of these alternative secondary support systems.

Jan 1, 1996

By T. Lux, H. -J. Krassnig, I. Filzwieser, E. Hecker, R. Degel, A. Filzwieser

Non-ferrous metals find their applications in smartphones, tablets and computers. These materials with their particular properties are the basis of our modern life. SMS group is well prepared for this huge market and for growing future challenges. A large contribution here is the new joint venture PolyMet Solutions that was founded by SMS group and Mettop, an Austrian engineering company, with the objective to develop new technical solutions for the primary copper production lines as well as for non-ferrous metals starting with the primary smelting of concentrate and ending with the electrolysis. PolyMet Solutions provides the process know-how whereas SMS group supplies the plants and equipment and Mettop the key components. SMS group and Mettop also cooperate in the field of tankhouse technology. Together with Montanwerke Brixlegg AG, Mettop has developed together with a parallel flow technology (METTOP-BRX Technology), allowing a current efficiency of above 98 % at a current density of 420 A/m², which is a milestone in copper electrolysis. For the secondary copper production route, SMS group and PolyMet Solutions developed an innovative refining furnace (PolyRefine) for the smelting and refining of copper scrap. The refined copper is directly charged to the Contirod line to produce copper rods and wires. The innovative cooling solutions of SMS and PolyMet Solutions come into play where furnaces have to stand the highest loads and stresses, for instance in areas of very high temperatures or temperature fluctuations, aggressive exhaust gases and slags, or at critical spots such as taphole areas. Custom-tailored cooling systems for furnace vessels make sure varying loads are compensated in a targeted and effective manner. The solutions include air cooling, spray cooling, cooling technologies with integrated copper elements such as CFM (Composite Furnace Modular) cooling systems, plate and finger coolers. The major innovation in the field of furnace cooling is the ILTEC (Ionic Liquid Cooling) Technology which paves the way for increased plant safety. This revolutionary, patented cooling technology is jointly marketed by Mettop and SMS group. It permits water-free cooling to be implemented and thus makes operation safe wherever it is applied. INTRODUCTION Non-ferrous metals or NF metals are changing the world. There is no modern industrial sector that can do without these valuable metals. Non-ferrous metals find their applications in smartphones, tablets and computers. These materials with their particular properties are the basis of our modern life. The importance of the non-ferrous metals market is reflected by two figures. In 2018, the production of non-ferrous metals was worth more than 237 billion Euros. This contrasts with 255 billion Euros of the value of iron and ferro- alloy production in the same year (International Organizing Comittee for the World Mining Congresses, 2018). Hence, the NF metal industry is almost as important as the iron and steel industry. SMS group is well prepared for this huge market and for growing future challenges. A large contribution here is the new joint venture PolyMet Solutions that was founded by SMS group and Mettop, an Austrian engineering company, with the objective to develop new technical solutions and to enhance customer value. The prices of nearly all metals have come under pressure during the past few years. Therefore, competitive technologies are regarded a crucial factor to achieve success in this critical market situation respectively to stabilize the market position.

Jan 1, 2019