Raymond Suglo

... in Ghana over the years and to suggest useful guidelines in mineral policy formulation to attract more foreign investment to ... to contract mining as most companies in Ghana have contracted out their mining operations to mining and service contractors. Ghana Mining Journal Vol. ...

... foreign-owned, have acquired prospecting licences. At least five new companies have started production, bringing the number of large-scale mining companies to nine. In addition, about 650 licensed small-scale mining groups are in operation. The economic and technological ...

Mineral processing is an essential component of a mine production chain and it accounts for significant proportion of the production cost. Over the past decade, significant research progress has been made in processing plant efficiency using theoretical, experimental and simulation modelling techniques. However, these studies are limited to process plant system as stand-alone units with no interactions with the mining units. In order to maximise the total mining system efficiency and more accurately simulate the system, the processing plant must be modelled as part of an integrated mining system. This becomes increasingly important in continuous surface mining systems, with limited ore processing capacity. In addition, plant efficiency is roughly estimated with known parameters or with simplistic statistical data, without regards to the stochastic processes governing these parameters, such as processing plant feed introduction. In this paper, a comprehensive model of the ore processing plant system is given and the object-oriented design (OOD) of the system is briefly introduced. The joint operation of ore processing plant system and haulage system is analysed. Numerical modelling is used to analyse the ore processing plant system under different conditions. Analysis of the results show that the optimum plant capacity is 0.7 tons/sec (2520 tons/hour). The results also show that the plant system resources cannot be fully utilised because the production rate is always less than the plant capacity. When plant capacity reaches an optimum value 0.7 tons/sec, the production rate is about 0.64 tons/sec. The underlying stochastic processes associated with plant and mine capacities cause this variability. In order to reduce this variability, there is the need to tightly set tolerances for the function variables

The coal mining industry is an important sector of Canada\u27s economy. The cost of mining and haulage of coal in Western Canada is a major focal point when compared to inexpensive coal from Australia. Spot coal price volatility affect contractual price arrangements and this creates pressure on companies\u27 profit margins and their competitive edge. In order to alleviate this pressure, companies may have to take short-term drastic measures that may hurt their strategic positions in the long-term. Companies must also create a mix of their products to ensure effective maintenance of profit margins given various quantity and quality constraints. In this paper the authors provide extensive analysis based on detailed probabilistic production systems for coal extraction and haulage in Western Canada. An optimization model is formulated for typical coal mining operations, processing and haulage from mine sites to the Vancouver Ports using linear programming algorithm. A stochastic model is also formulated to analyze the associated risks and uncertainties. These models are validated using data from five operating mines in Western Canada with varying quantity and quality products and uncertainties. The results show that the five mines studied have to produce between 180,000 and 2.10 million tonnes of metallurgical coal and between 70,000 and 2.16 million tonnes of thermal coal to enhance their profitability given the underlying constraints. The average expected probability of success associated with production capacities from these mines is about 66%. This results in a failure probability of 36%, which is extremely high under contractual arrangements. The results also show that management\u27s profit expectation of $83 million can be achieved at a zero percent failure probability. With a higher risk of failure of 10%, this expectation increases by 21% to $100.3 million

The evolution of surface mine layout configuration is a function of the schedules and sequence of material excavation within the optimized layouts. The production schedules and sequence of materials movement from multi-bench and multi-face operations are difficult to plan and execute. However, the ability to maximize the profit or net present value of an orebody is largely dependent on the mining schedule. The mining schedule will determine the life of the mine, the projected cashflows, and the investment requirements over the mine life. The pit geometries, pit expansion rates and the periodic volume of materials from different benches in a multi-bench, multi-face open pit mine determine the equipment requirements. The volume of materials excavated, as well as pit layout changes from circular and elliptical geometries of an oil sands mine were modeled using analytical geometric and parabolic partial differential equations (PDEs) and solved within Matlab. The results show that the geometric values are almost the same as those obtained from PDEs for different pit configurations. The economic analysis shows that both the current mining system (CMS) and the cyclic excavator conveyor belt control system (CycEx CBCS) are viable with high NPV (= $3.20 x 1010), PI (\u3e 19%) and IRR (\u3e 29.02%) with short discounted payback periods (= 3.24 months). The CycEx CBCS option is more economic than the CMS option. Its NPV is 1.27 times that of the CMS option. The PI and IRR for the CycEx CBCS option are respectively 2.24 and 1.13 times that of the CMS option. As well, the CycEx CBCS option has almost half the DPBP of the CMS option. The CMS option has an operating cost of $1.386 per tonne ($2.774/barrel) while that of the CycEx CBCS option is $0.779/tonne ($1.558/barrel). These results show that the CycEx CBCS option is the better option for mining companies working on oil sands deposits to invest in

In this paper, three mining operations are modeled using Visual SLAM with AweSim software. These operations involve a continuous surface miner-truck mining system in a strip coal mine, a continuous miner-shuttle car system and hoist scheduling system both in an underground coal mine. The ever-increasing cost of labor, energy and equipment together with low prices of most minerals on the market threaten the profitability of most mines. It is necessary to closely monitor the performance of the system drivers in mining operations to ensure maximum system efficiency. This paper investigates the performance of three mining models to determine the best equipment combinations and schedules that will enable the mines meet their production targets. The results show that in the CSM-truck model, the optimum fleet size is five 90-tonne trucks which produces 847,080 tonnes with 99.2% utilization of the CSM. When the number of parallel servers at the FB location is increased from one to two in the CM-shuttle car model, the production increases by 73% with shorter queue lengths, reduced number of balked units and an improvement in server utilization in all combinations. In the single hoist scheduling model, the number of loads moved through the system increased by 9% from 1617 to 1764 with scheduling, and the average time in the system fell from 725.844 min. to 104.922 min. The results also show that computer simulation is an excellent tool for evaluating mining models and for gaining a greater understanding of mining systems. 2. Continuous Surface Miner Truck Mining System 2.1 Problem Formulation In this scenario, it is desired to develop a Visual SLAM model to simulate the operation of a continuous surface miner (CSM) truck system that is employed to mine a thick coal seam in a strip mine. Extraction of the ore at the face is done by advancing the CSM which has a rotating cutter head which undercuts the layers of coal. The material cut by the CSM is loaded into 90-tonne capacity trucks by means of a pivot-mounted belt conveyor. After loading three trucks, the CSM must turn around to begin the next cutting strip of coal. The loaded trucks haul the material to a central stockpile location. The empty trucks then return to the CSM for loading. The model is designed such that the loaded trucks can dump their materials at multiple open dumping bays at the central stockpile (i.e. there is no spotting time at the central stockpile location). Initially, three 90-tonne rear dump trucks are allocated to the CSM. Fig. 1 a section of a strip mine with the blocks of coal exposed and numbered in layers. Each labeled block of coal is equivalent to three 90-tonne truckloads

The mechanization of mining operations in underground coal mines has led to faster cutting rates of coalfaces with increased levels of emission of gaseous and particulate contaminants in the workings. Consequently, the fresh air streams from the main ventilation systems reaching distant workings are often insufficient, ineffective or inadequate and have to be supplemented by auxiliary ventilation systems to create and maintain the required working environments underground. The efficiencies of auxiliary ventilation systems are largely affected by drivers of the system such as the type and capacity of the fan; the type, length, diameter and condition of the ventilation ducting and the distance from the discharge end of the intake ducting to the face. Traditionally, single point measurements of methane gas concentrations using either flame safety lamps or hand-held measuring instruments have been used to assess how safe underground coal workings were. Unfortunately, such occasional measurements of methane gas concentrations do not give an accurate picture of the real gas concentration in the working as they are often taken from the easily accessible locations in working. Continuous monitoring of the methane gas concentration in development headings enables a better assessment of the environmental conditions prevailing there. All variations in the methane concentrations are more easily captured on a continuous monitoring basis than by instantaneous single point measurements. The approach adopted in this work was to continuously monitor the concentration of methane very close to the face and about 60 m outbye in development headings, observe the types of auxiliary ventilation equipment and their sizes being used in the working as well as noting the lengths from the discharge ends of the forcing and exhaust ductings to the face. In this paper, empirical methods are used to calculate the mean efficiencies of the auxiliary ventilation systems in selected development headings in coal mines in North America. This enables the assessment of the effectiveness of the auxiliary ventilation systems and the identification of the system drivers in them. The result show that the efficiencies of the forcing systems ranged from 17.02% to 96.81% while the efficiencies of the overall systems varied from 6.04% to 54.16%. The distance from the discharge end of the intake ducting to the face appeared to be the strongest driver in the performance of the auxiliary ventilation systems studied. It was also noted that when the discharge end of the intake ducting to the face does not exceed 7 m, there were faster purging rates of methane at the face and the efficiencies of the overall auxiliary ventilation system were greater than 50%. These findings are very important in underground coal mining in North America as they will assist to avert calamities, such as the Westray coal mine disaster in 1992 which resulted from the explosion of methane gas, by identifying which components of the ventilation system need special attention to create safe working conditions underground.

The preparation of graduate talent for the mining industry is a challenging process, given the multifaceted and complex array of decisions mining engineers make in discharging their responsibilities. As leaders, mining engineers must manage operations, lead project teams, mentor junior engineers, chart the technological directions of companies and deal with several organizations for maintaining the technical and economic feasibility of operations within strategic and tactical framework. Traditionally, the completion of the bachelor of science degree curriculum, with a minimum cumulative grade point average (CGPA), has been used as a graduation measure by Missouri University of Science and Technology (Missouri S&T). Companies have long realized the limitations of the CGPA for recruiting graduates because mining engineering is an applied engineering discipline. Company recruiters have sought to correct the limitations by factoring experience and behaviors into the selection process when recruiting knowledgeable and well-rounded graduates. In this paper, the authors introduce a new metric, which combines the current CGPA (knowledge) with experience and attribute (KEA) metrics to gauge the job readiness of graduating engineers. The KEA metric, also called the job-readiness factor (JRF), is the sum of K (50%), E (30%) and A (20%). The KEA process has been applied to a graduating class in Missouri S&T to demonstrate the value of the new metric system. The results show a fairly positive correlation between CGPA and the KEA metric, with a coefficient of determination of about 70%. Overall, the KEA metric system provides a better picture of the capacity and job readiness of graduates entering the workforce. Copyright © 2013 by the Society for Mining, Metallurgy and Exploration, Inc

... Raymond Suglo has professional experience in teaching, research and underground mining operations. ... (AIME). Samuel Frimpong is an associate professor and the director of the Centre for Advanced Mine Design Research (CAMDeR) established at the University of Alberta. ...

Sewage generated in Ghana is commonly discharged into the environment without any form of treatment to reduce the degree ofcontamination and mitigate potential public health and environmental issues. Although some attempts have been made in someparts of Ghana to utilize the waste stabilization pond (WSP) system to treat domestic sewage, the ponds often fail to achievetheir purpose due to lack of basic maintenance and supervision. To assess the utility of the WSP system for treating sewage,wastewater samples were collected from the raw sewage, anaerobic, facultative and maturation ponds of WSPs at Obuasi inGhana, and analyzed for physicochemical and microbiological contaminants. The results show that the final pond effluent meetsrecommended microbiological and chemical quality guidelines. The waste stabilization pond system demonstrates high removalefficiencies of wastewater contaminants. The biochemical oxygen demand, total suspended solids, nitrate and faecal coliformsreduction efficiencies of 97.3%, 97.6%, 83.3% and 99.94% respectively are highly significant, and compare well with reportedremoval efficiencies in the literature. Additionally, the ponds have high reduction efficiencies for heavy metals and pathogenicmicroorganisms. The wastewater treatment system complies with standard wastewater management practices, and provides auseful method for treating and disposing wastewater in Ghana.

Morupule Coal Mine (MCM) classifies fines as coal particles that are less than 3.35 mm in size. Fines are one of the problems MCM is facing and have occasionally led to penalties from some customers. This paper quantifies the fines generated in MCM from the working face to the run-of-mine stockpile and its economic and environmental impacts. Data about the wash plant's production losses were collected through an examination of missed deadlines, stoppages due to tail-end blockages, and conveyor belt breakdowns using company reports. Data on coal dust concentrations were obtained from the mine. It was found that the overall haulage system generates about 27% of the fines of the coal produced monthly. The total monetary loss per shift from production and the wash plant is BWP 418,285. Coal dust concentration underground is kept within acceptable limits due to strict engineering control measures while it exceeds the required levels on the surface and is difficult to control as it is...

The shovel-truck system is commonly used in open-pit mining operations. Truck haulage cost constitutes about 26% of open-pit mining costs as the trucks are mostly powered by diesel whose cost is escalating annually. Therefore, reducing fuel consumption could lead to a significant decrease in overall mining costs. Various methods have been proposed to improve fuel efficiency in open-pit mines. Case-based reasoning (CBR) can be used to estimate fuel consumption by haulage trucks. In this work, CBR methods namely case-based reasoning using forward sequential selection (CBR-FSS), traditional CBR, and Naïve techniques were used to predict fuel consumption by trucks operating at Orapa Mine. The results show that the CBR method can be used to predict fuel consumption by trucks in open-pit mines; the predicted values of fuel consumption using the CBR-FSS technique gave much lower absolute residual values, higher standardised accuracy values, and effect sizes than those of other prediction t...

Surface mine production systems involve complex, multi-faceted and costly sequence of processes that must be planned, designed and evaluated to promote well-conditioned decision processes. Strategic and tactical mine plans are used to provide a long-term production vision and the resource requirements for meeting specific periodic mine and plant capacities. The schedule and sequence of material movement must respond quickly to changing technical, safety and economic constraints within the surface mining environment. Many production planning, scheduling and resource allocation methods are based on simplistic methodologies without rigorous technical and economic basis. These methods fail to consider the random processes governing critical production variables. With increasing demand for efficient schedules for low-cost bulk production requirements, the need for efficient tools is critical. In this study, the authors develop an innovative pit shell simulator to address these problems. Rigorous geometric formulations of the ellipsoidal approximations of the pit shells geometry, their planar expansions and vertical interactions are modeled to mimic material displacement dynamics in an open pit operation. Numerical simulation techniques are used to provide solutions to the time-dependent geometric models in random multivariate states. The pit shell simulator is used to solve the Pine Valley open pit mine production schedule for the first three years of production. The simulator provides the schedule and sequence of all the cuts from various quadrants in the four pit shells within the optimised pit layout. The simulator results show that, in order to maximize the mine value, the mine must produce 304,000, 180,000 and 140,000 tonnes of ore respectively for years 1, 2 and 3. The total materials within this period also include 72,000, 80,000 and 190,000 tonnes of stockpiles and 30,000, 80,000 and 30,000 tonnes of waste materials respectively for years 1, 2 and 3. This results in a maximum NPV of $27,000 at a discount rate of 12 percent over the 3-year duration.

When the final feasibility report on a new mine indicates that it is feasible under the prevailing technological and economic conditions to develop the project into an open pit mine, mine managers are often faced with the problem of determining the capacities, fleet sizes and how to match the materials handling equipment to ensure maximum production and profitability of the mine. One option is to use the results from other operating mines in similar geographic, geological and economic environments. Of late, most mine managements are increasingly depending on the results of computer simulations of their operations to determine the capacities, fleet sizes, for equipment matching. This paper uses the Visual SLAM with AweSim simulation software to determine the optimum fleet sizes of Kantaayele Goldfields Ltd., a gold mine in Ghana, which will enable the mine to meet its waste stripping and ore production targets. The use of simulation techniques as a tool in the modeling, formulation and testing of several models in the ore and waste mining operations of the mine are demonstrated. The results obtained from the simulation runs show that the mine cannot achieve its targets in ore mining and waste stripping with its initial fleets operating over 7.5-hour shifts per day. Using waiting times and queue lengths at the shovel and crusher locations as the determinants, the optimum fleet size for ore mining was found to be Option E with six 80-tonne trucks operating over 1350 minutes. For the waste stripping operations, the optimum fleet size was determined to be fourteen 80-tonne trucks. Ghana Mining Journal Vol. 9 2007: pp. 25-32

ABSTRACT Excavation methods depend on the rock conditions, location, etc. This paper investigated the penetration of an excavator blade into soil. Finite element modelling using the ABAQUS software and analytical methods were used to predict the horizontal forces due to blade movement with varying soil parameters such as friction angle, cohesion coefficient, and angle between soil and blade. The results obtained from the numerical and analytical models compare favourably with each other in the prediction of soil cutting resistance. The depth of soil, internal friction angle and cohesion coefficient were found to be directly related to the cutting resistance of soil.

Wastewater produced from many industrial operations has to be treated before being allowed to join the natural water body. Wastewater stabilization pond technology (WSPT) is an important natural and cost-effective wastewater treatment method
for the removal of pathogenic micro-organisms in tropical countries like Ghana, because of the intensity of the sunlight and temperature.

In Ghana, almost all the domestic sewages are discharged into the environment without treatment. To avoid polluting nearby streams and surface water body, sewage generated in the residential areas of Obuasi is managed by applying Waste
Stabilisation Ponds Technology. This paper studied the WSPT at Obuasi. Physico-chemical and microbiological analyses were done to the samples collected from wastewater ponds. The results showed that the wastewater quality parameters of the
effluent from the last pond meet the threshold values set by the Environmental Protection Agency (EPA), Ghana and can safely be discharged without any adverse effect to the environment. The Biochemical Oxygen Demand, Total Suspended
Solids, Nitrate and Faecal Coliforms removal efficiencies of the pond were 97.3%, 99.5%, 83.3% and 99.94% respectively. The wastewater management system was found to be effective and it is recommended to be introduced in all other parts of
the country.

Exergy analysis provides useful means to evaluate and identify the sources of thermodynamic inefficiencies within each system component. This paper tries to analyze the combustion in a simple gas turbine system by comparing the effect of variation of species concentrations in the combustion process. Both complete and equilibrium combustion models as well as gas equilibrium software are used to perform the exergetic evaluation of the simple gas turbine system with a rated output of 50 MW. The complete combustion model involved O 2 , N 2 , CO 2 and H 2 O while the equilibrium combustion model involved N 2 , O 2 , CO 2 , H 2 O, CO, H 2 , H, O, OH and NO as the species of combustion products. The results show that the thermo-mechanical exergy rate is higher in the equilibrium combustion model than that of the complete combustion model and this increase is caused by the addition of species in the combustion product. Exergetic evaluation gave the values of 49.993 MW and 56.467 MW for the thermo-mechanical exergy rate for the complete and equilibrium combustion models respectively.

The availability and the utilisation of drill rigs have great impact on the output of a mine. These can be optimised by reducing the downtimes and operational delays to ensure high availability and utilisation, and consequently higher productivities. In this paper, the causes of the numerous rig breakdowns at Kanjole Minerals Ltd. (KML) were investigated, the availability and utilisation of the rigs were estimated and the impact of the availability and utilisation of the rigs on the mine's production evaluated. Iron ore occurs on five hills at KML. Five drill rigs which are currently in operation at KML were studied in this work. The causes of the rig breakdowns observed include hose burst, overheating, shank adapter breakage and change out, rod breakage, low flushing, percussion and rotation pressures, track removal and breakage and drilling chain breakage. The operating data of the rigs were entered into drill log books during drilling operations. The period of study was from ...