The document discusses pioneering large diamond recovery at the Karowe Diamond Mine using X-ray transmission (XRT) sorting technology. Some key points:
- XRT sorting was selected for its ability to detect diamonds based on atomic number, without needing clean or reflective particle surfaces like other technologies.
- The XRT circuit was designed to sort material into different size fractions for processing. This included bins, feeders and XRT machines to match throughput to material size.
- Commissioning involved testing the XRT machines using tracer diamonds and optimizing settings without material first, then ramping up production with material feed.
- Performance data is provided on throughput capacities, water cooling requirements, compressed air use and tracer
The document summarizes the commissioning and operation of an autogenous mill at the Karowe Diamond Mine in Botswana. An autogenous mill, a first for African diamond processing, was selected over traditional crushing circuits to process the mine's ore. During early commissioning, challenges arose from operating in an unfamiliar environment without precedents to benchmark against. These challenges were overcome, and the mill was optimized to liberate diamonds while minimizing damage. While more work is required to improve processing of fine diamonds, the autogenous mill has performed well overall in handling the mine's varied ore types.
This document discusses technologies and techniques for upgrading coarse and fine iron ore, including dense media separation, jigging, magnetic separation, flotation, and x-ray processing. It describes how the selection of a beneficiation method and flowsheet depends on the ore mineralogy. Common beneficiation techniques are reviewed for different particle size ranges. Examples of global iron ore plants employing various processing methods are provided for different deposit types. Beneficiation characteristics that are important to consider, such as recovery, are also outlined.
This document summarizes a study on optimizing ball mills for clinker grinding in cement plants. It presents empirical equations relating particle size reduction to specific energy requirements. Data from plant operations and lab experiments on grinding various materials to the superfine and nanoscale are used. Equations are proposed to estimate parameters like particle size, surface area, and energy consumption quickly. Calculations are performed to quantify design parameters that can significantly reduce energy for clinker grinding, such as selecting optimal ball size and configuration. The use of additives like fly ash and grinding aids is also investigated for improvements to grinding efficiency and cement strength.
This document discusses improving fines recovery in mineral processing by grinding finer. It begins by noting the conventional view is that fine particles have low flotation recovery, but some plants achieve high recovery of fine particles by grinding finer. The key points are:
1) Whether fines can be recovered well depends on mineralogy - if minerals are not fully liberated, grinding finer is needed. Plants with coarse-grained ores do not need to grind as fine.
2) Circuit design and operating strategy must suit the needs of fine particles. Narrow particle size distributions in flotation and avoiding overgrinding of coarse particles helps recovery.
3) Case studies at Mount Isa Mines show improving recovery 5-10
This document discusses the determination of the Bond work index of limestone samples from Lucky Cement Limited in Pakistan. The Bond work index test involves grinding limestone samples in a ball mill and measuring the grindability over multiple cycles. Test results found that 6 of 7 limestone samples had a Bond work index over 20 kWh/t, qualifying them as "hard rock." However, one sample from Face-4A had a Bond work index under 20 kWh/t, indicating it was less energy intensive to grind and had higher grindability than the other samples. This study aims to help optimize energy efficiency in limestone grinding operations at Lucky Cement.
IRJET- Experimental Investigation on Partial Replacement of Fine Aggregate by...IRJET Journal
- The document experimentally investigates partially replacing fine aggregate with foundry sand in concrete mixtures.
- Tests were performed on concrete mixtures with 0-50% replacement of fine aggregate by foundry sand. Results showed compressive strength increased up to 30% replacement for M20 concrete and 40% replacement for M25 concrete.
- Higher replacements led to strength decreases. Therefore, foundry sand can partially replace fine aggregate in concrete, improving strength and providing an outlet for the waste foundry sand.
IRJET- An Experimental Study on Air Entrained Mortar by Utilising Lather AgentIRJET Journal
This document presents research on producing an air-entrained mortar utilizing sugarcane ash and a lather agent. Mortar samples were produced with 10%, 30%, and 50% cement replaced by sugarcane ash. The samples were tested for compressive strength and water absorption at 7, 14, and 28 days. Results showed compressive strengths of 11.2 MPa, 8.5 MPa, and 7.3 MPa respectively for the 10%, 30%, and 50% sugarcane ash replacements compared to 12.5 MPa for a conventional mortar. Water absorption also increased with higher sugarcane ash content. The study concludes the mortar produced is beneficial due to lower cost and weight while being
This document provides an overview of cement mill operations, including definitions, types of grinding circuits, mill dimensions, operating speeds, structure of the mill components, grinding media, ventilation, heat generation and cooling, power consumption calculations, air separators, fineness control, and storage of materials. It describes the key components of a cement mill, such as the shell, liners, partition screens, grinding balls, and separators. It also explains concepts like critical speed, power calculations, and efficiency formulas for air separators.
The document summarizes the commissioning and operation of an autogenous mill at the Karowe Diamond Mine in Botswana. An autogenous mill, a first for African diamond processing, was selected over traditional crushing circuits to process the mine's ore. During early commissioning, challenges arose from operating in an unfamiliar environment without precedents to benchmark against. These challenges were overcome, and the mill was optimized to liberate diamonds while minimizing damage. While more work is required to improve processing of fine diamonds, the autogenous mill has performed well overall in handling the mine's varied ore types.
This document discusses technologies and techniques for upgrading coarse and fine iron ore, including dense media separation, jigging, magnetic separation, flotation, and x-ray processing. It describes how the selection of a beneficiation method and flowsheet depends on the ore mineralogy. Common beneficiation techniques are reviewed for different particle size ranges. Examples of global iron ore plants employing various processing methods are provided for different deposit types. Beneficiation characteristics that are important to consider, such as recovery, are also outlined.
This document summarizes a study on optimizing ball mills for clinker grinding in cement plants. It presents empirical equations relating particle size reduction to specific energy requirements. Data from plant operations and lab experiments on grinding various materials to the superfine and nanoscale are used. Equations are proposed to estimate parameters like particle size, surface area, and energy consumption quickly. Calculations are performed to quantify design parameters that can significantly reduce energy for clinker grinding, such as selecting optimal ball size and configuration. The use of additives like fly ash and grinding aids is also investigated for improvements to grinding efficiency and cement strength.
This document discusses improving fines recovery in mineral processing by grinding finer. It begins by noting the conventional view is that fine particles have low flotation recovery, but some plants achieve high recovery of fine particles by grinding finer. The key points are:
1) Whether fines can be recovered well depends on mineralogy - if minerals are not fully liberated, grinding finer is needed. Plants with coarse-grained ores do not need to grind as fine.
2) Circuit design and operating strategy must suit the needs of fine particles. Narrow particle size distributions in flotation and avoiding overgrinding of coarse particles helps recovery.
3) Case studies at Mount Isa Mines show improving recovery 5-10
This document discusses the determination of the Bond work index of limestone samples from Lucky Cement Limited in Pakistan. The Bond work index test involves grinding limestone samples in a ball mill and measuring the grindability over multiple cycles. Test results found that 6 of 7 limestone samples had a Bond work index over 20 kWh/t, qualifying them as "hard rock." However, one sample from Face-4A had a Bond work index under 20 kWh/t, indicating it was less energy intensive to grind and had higher grindability than the other samples. This study aims to help optimize energy efficiency in limestone grinding operations at Lucky Cement.
IRJET- Experimental Investigation on Partial Replacement of Fine Aggregate by...IRJET Journal
- The document experimentally investigates partially replacing fine aggregate with foundry sand in concrete mixtures.
- Tests were performed on concrete mixtures with 0-50% replacement of fine aggregate by foundry sand. Results showed compressive strength increased up to 30% replacement for M20 concrete and 40% replacement for M25 concrete.
- Higher replacements led to strength decreases. Therefore, foundry sand can partially replace fine aggregate in concrete, improving strength and providing an outlet for the waste foundry sand.
IRJET- An Experimental Study on Air Entrained Mortar by Utilising Lather AgentIRJET Journal
This document presents research on producing an air-entrained mortar utilizing sugarcane ash and a lather agent. Mortar samples were produced with 10%, 30%, and 50% cement replaced by sugarcane ash. The samples were tested for compressive strength and water absorption at 7, 14, and 28 days. Results showed compressive strengths of 11.2 MPa, 8.5 MPa, and 7.3 MPa respectively for the 10%, 30%, and 50% sugarcane ash replacements compared to 12.5 MPa for a conventional mortar. Water absorption also increased with higher sugarcane ash content. The study concludes the mortar produced is beneficial due to lower cost and weight while being
This document provides an overview of cement mill operations, including definitions, types of grinding circuits, mill dimensions, operating speeds, structure of the mill components, grinding media, ventilation, heat generation and cooling, power consumption calculations, air separators, fineness control, and storage of materials. It describes the key components of a cement mill, such as the shell, liners, partition screens, grinding balls, and separators. It also explains concepts like critical speed, power calculations, and efficiency formulas for air separators.
Influence of using white cement kiln dust as a mineral filler on hot asphaltIAEME Publication
This document discusses using white cement kiln dust (WCKD) as a mineral filler in hot asphalt concrete mixtures. WCKD is a byproduct of cement production that is usually disposed of, but can provide economic and environmental benefits if used in asphalt mixtures. The document reports on a study that used various percentages of WCKD, alone and combined with cement and limestone, to prepare asphalt mixtures. Standard tests showed that mixtures with WCKD met specifications and performed similarly to mixtures with traditional fillers. The results indicate that using WCKD as a filler can reduce waste and costs for asphalt producers while maintaining quality.
IRJET- Comparative Study of Different Strength for Different Mixer by using F...IRJET Journal
The document presents a comparative study on the mechanical properties of concrete with different mixtures using fly ash, quarry dust, and 6mm coarse aggregate as replacements for cement, fine aggregate, and coarse aggregate respectively. Seven different mixtures were tested for properties like compressive strength, split tensile strength, and modulus of rupture at 21 and 28 days. The results showed that a mixture with 30% replacements of cement with fly ash, fine aggregate with quarry dust, and coarse aggregate with 6mm chips achieved 90% of the compressive strength of normal concrete. The study aims to utilize waste materials like fly ash, quarry dust, and stone chips in concrete production.
IRJET- Experimental Analysis of M-25 Grade Concrete with Usage of Waste F...IRJET Journal
This document presents an experimental study on the use of waste foundry sand as a partial replacement for fine aggregate in concrete. M-25 grade concrete was prepared by replacing fine aggregate with 0%, 10%, 20%, 30%, 40%, 50%, and 60% waste foundry sand. The compressive strength was found to initially decrease and then increase with 40% replacement achieving the maximum strength. The split tensile strength was found to decrease with increasing waste foundry sand content. Using waste foundry sand provides benefits such as reducing the cost of concrete by 20 times and providing an eco-friendly solution for disposal of waste from foundries.
Nil Waste Process Evolution for a Low Grade LimestoneIRJET Journal
This document summarizes research on developing a nil waste process for beneficiating a low-grade limestone using reverse cationic flotation.
The limestone sample contained mainly calcite and quartz and was analyzed to contain 45% CaO and 80% total carbonates. Grinding and flotation tests were conducted varying parameters like mesh of grind, collector type and dosage. The optimum conditions found were a mesh of grind of D80 400 microns, using 0.4 kg/t of cationic collector SOKEM565C. This produced a cement-grade concentrate assaying 90% total carbonates at an 88% weight yield. The non-float fraction assaying 80.30% Al
IRJET- Evaluation of Compressive Strength of Mortars Containing Stone Dust as...IRJET Journal
This document presents the results of a study that evaluated the compressive strength of mortar mixes containing stone dust as a partial replacement for river sand. Mortar cubes were prepared with 0%, 25%, and 50% replacements of sand by stone dust. The cubes were tested for compressive strength at 3, 7, and 28 days. The results showed that mortar mixes with up to 50% replacement of sand with stone dust met the minimum compressive strength standards. Therefore, the study concluded that stone dust can partially replace river sand in mortar mixes without negatively affecting compressive strength.
Recent growth of construction
industry has increased the demand of cement.
Increase of the cement utilization demands for
higher production efficiency and ultimately low
production cost. The efficiency of the cement
production depends greatly upon the efficiency of
a grinding mill which consumes 60-70% of the
total electricity consumption of the cement
plant[12]. A grinding mill (Ball Mill) is used to
grind the cement clinker into fine cement powder.
Grinding Aids are used to improve the grinding
efficiency and reduce power consumption. This
paper discusses the grinding aids mechanism and
improvement in grinding efficiency due to various
grinding aids viz .polyols, amines . This paper also
focus on the effects of grinding aids on the
mechanical properties of cement such as setting
time, specific surface, compressive strength at various ages.
Debranning has the aim to remove the outer layers of the pericarp from wheat kernels (Figure 1). Increasing number of industrial and research studies reports the advantages of debranning Durum wheat prior to milling:
Effect on Compressive and Tensile Strength of Cement Concrete Road Pavements ...IRJET Journal
This document summarizes a study on using iron ore tailings to partially replace fine aggregate in cement concrete used for road pavements. Concrete cubes and cylinders were cast with 0-50% replacement of sand with iron ore tailings. Compressive and flexural strength were tested at 7, 21, and 28 days. Results showed that compressive and flexural strength increased up to 30-40% replacement, but then started decreasing at 50% replacement. The study concluded that iron ore tailings can effectively replace a portion of fine aggregate in concrete, improving utilization of this waste material without compromising strength.
IRJET- Experimental Investigation on Partial Replacement of Rice Husk Ash as ...IRJET Journal
The document experimentally investigates the use of rice husk ash as a partial cement replacement and coconut shell as a partial coarse aggregate replacement in producing lightweight concrete. Seven concrete mixes were prepared with coconut shell replacing conventional aggregates at 0%, 5%, 10%, 15%, 20%, and 25% and rice husk ash kept constant at 10% cement replacement. The mechanical and durability properties of the mixes were then evaluated. The results showed that the mix with 10% rice husk ash and 10% coconut shell replacement provided good mechanical properties while also offering the advantages of utilizing waste materials and reducing natural resource depletion, suggesting coconut shell could be a feasible aggregate replacement in concrete production.
This document discusses optimizing cement grinding circuits through pre-crushing of clinker using a Barmac crusher prior to grinding in a two-compartment ball mill. Bond calculations and population balance modeling are used to analyze the potential benefits. Modeling suggests the total energy consumption for grinding can be reduced up to 10% by pre-crushing clinker to a finer size before ball milling. A case study of a cement plant found pre-crushing could lower the required ball mill power by 9-15% and increase grinding circuit capacity with relatively low capital investment compared to alternatives like high-pressure grinding rolls.
An Investigation on Strength and Durability of Cement Concrete Partially Repl...IRJET Journal
This document investigates using granite slurry as a partial replacement for cement in concrete. Granite slurry is a waste material from rock quarrying and crushing. The study tested concrete mixtures with 5-20% cement replacement using granite slurry under 75 microns. Tests found compressive and flexural strength were maintained with up to 10% replacement after 28 days. Higher replacements showed strength decreases. The study concluded granite slurry can be used for partial cement replacement, providing both economic and environmental benefits by reducing costs and waste. Up to 5% replacement provided optimal strength properties.
IRJET- Studies on Geopolymer Concrete with GGBS as Partial Replacement to...IRJET Journal
This document presents a study on geopolymer concrete with ground granulated blast furnace slag (GGBS) as a partial replacement for fly ash. Various mixtures of geopolymer concrete were prepared by replacing fly ash with GGBS at percentages from 0% to 100%. Sodium silicate and sodium hydroxide solutions at molarities of 8M, 10M and 12M were used as alkaline activators. Specimens were oven cured and tested for mechanical properties like compressive strength, flexural strength, and split tensile strength at 14 and 28 days. Test results showed that mechanical properties were highest for a mixture with 12M alkaline activator concentration and 100% GGBS replacement of fly ash. The
This thesis developed a virtual environment for simulating cone crusher performance using the discrete element method (DEM). Industrial scale experiments were conducted on a Svedala H6000 cone crusher to collect pressure, power and particle size data. The crusher liner geometries were 3D scanned. Two DEM simulations were performed using a bonded particle model to represent rock breakage. The first simulation did not match experiments well but the second, using a closer setting, showed good agreement with experimental pressure and throughput values, validating the DEM model. Further work is needed to calculate particle size distributions from the unbroken clusters.
IRJET- An Experimental Study on Performance of Ternary Blended High Strength ...IRJET Journal
This study experimentally investigates the performance of ternary blended high strength fiber reinforced concrete. Various mixtures were tested by replacing cement with ground granulated blast furnace slag and metakaolin at different percentages, and adding steel and glass fibers at amounts up to 2% by weight. The results showed that ternary blended fiber reinforced concrete exhibited higher compressive strength, tensile strength, and improved stress-strain behavior compared to normal concrete without additions.
IRJET-Experimental Study on Corn Cob Ash Powder as Partial Replacement of Cem...IRJET Journal
1) The study experimentally evaluates using corn cob ash (CCA) as a partial replacement for cement in concrete. Various percentages (0%, 10%, 20%, 30%) of CCA replacement were tested.
2) Results showed that compressive, flexural, and split tensile strengths were initially lower for CCA concrete but surpassed the control concrete at later ages, indicating the pozzolanic effect of CCA over time.
3) The 10% CCA replacement mixture achieved higher strengths at 90 days compared to the control, suggesting 10% CCA is a suitable partial replacement for cement.
IRJET- An Experimental Study on Strength of Concrete with Partial Replacement...IRJET Journal
This document presents an experimental study on using copper slag and quarry dust as partial replacements for fine aggregate in concrete. Various concrete mixes were tested with copper slag and quarry dust replacements ranging from 0-45%. Specimens were cured for 7-28 days and tested for compressive, split tensile, and flexural strengths. The results showed that concrete with a 40% fine aggregate replacement achieved the highest compressive strength of 41.87 MPa. Split tensile strengths were also higher than the control mix for replacements up to 15%. Thus, the study demonstrates that using industrial wastes like copper slag and quarry dust as partial replacements for fine aggregate in concrete can improve strength properties while providing environmental and economic benefits.
Laboratory Investigation of Conventional Asphalt Mix Using Shell Thiopave for...IJERA Editor
The characteristic performance of asphalt pavement always depends on the properties of bitumen, volumetric properties of asphalt mixtures. Bitumen is visco– elastic material where the temperature and rate of load application have a great influence on its behavior. There are different solutions to reduce the pavement distress such as using Thiopave (binder extender and asphalt mixture modifier) in the mix design. Thiopave can significantly alter the performance properties of the mix and it is helpful to extend the life span of pavement. In this study, investigating use of thiopave and the change in the performance properties is dependent both on the percentage of virgin binder using VG-30 bitumen that is substituted with thiopave with different percentages. The study indicated that 10%, 20%, 30% and 40% replacement of binder was done with thiopave. The most notable impact of the addition of thiopave to a bituminous mixture is an increase in the stiffness of the mixture for better resistance to fatigue cracking and rutting. Thiopave materials can have a positive impact on laboratory mixture performance. The addition of thiopave has been shown to significantly increase Marshall Stability. From this study it is observed that thiopave can be utilized up to 30% to 40% as replacement to bitumen.
The document describes an XRT intelligent ore sorter that uses X-ray technology and sensors to identify and separate ore from waste rock. It has the highest precision and can process the largest range of particle sizes of any raw ore sorting equipment. The sorter improves mining efficiency by increasing ore grades, reducing waste, and allowing for recovery from tailings and slag. It has applications in sorting a wide variety of metal and non-metal ores.
Xrt x ray transmission ore sorter intelligent dry separation-hot mining_serenaSerena Fu
The document describes an XRT intelligent dry sorter produced by Beijing Hot Mining Tech Co Ltd. It has the highest precision, can process the largest particle sizes, and is the most stable system. The sorter uses X-ray technology and AI algorithms to sort raw ore, improving ore grades and reducing waste. It has applications in mining a variety of minerals like gold, silver, and copper. The sorter provides benefits like lower processing costs, improved efficiency and profits, and extended mine life.
Influence of using white cement kiln dust as a mineral filler on hot asphaltIAEME Publication
This document discusses using white cement kiln dust (WCKD) as a mineral filler in hot asphalt concrete mixtures. WCKD is a byproduct of cement production that is usually disposed of, but can provide economic and environmental benefits if used in asphalt mixtures. The document reports on a study that used various percentages of WCKD, alone and combined with cement and limestone, to prepare asphalt mixtures. Standard tests showed that mixtures with WCKD met specifications and performed similarly to mixtures with traditional fillers. The results indicate that using WCKD as a filler can reduce waste and costs for asphalt producers while maintaining quality.
IRJET- Comparative Study of Different Strength for Different Mixer by using F...IRJET Journal
The document presents a comparative study on the mechanical properties of concrete with different mixtures using fly ash, quarry dust, and 6mm coarse aggregate as replacements for cement, fine aggregate, and coarse aggregate respectively. Seven different mixtures were tested for properties like compressive strength, split tensile strength, and modulus of rupture at 21 and 28 days. The results showed that a mixture with 30% replacements of cement with fly ash, fine aggregate with quarry dust, and coarse aggregate with 6mm chips achieved 90% of the compressive strength of normal concrete. The study aims to utilize waste materials like fly ash, quarry dust, and stone chips in concrete production.
IRJET- Experimental Analysis of M-25 Grade Concrete with Usage of Waste F...IRJET Journal
This document presents an experimental study on the use of waste foundry sand as a partial replacement for fine aggregate in concrete. M-25 grade concrete was prepared by replacing fine aggregate with 0%, 10%, 20%, 30%, 40%, 50%, and 60% waste foundry sand. The compressive strength was found to initially decrease and then increase with 40% replacement achieving the maximum strength. The split tensile strength was found to decrease with increasing waste foundry sand content. Using waste foundry sand provides benefits such as reducing the cost of concrete by 20 times and providing an eco-friendly solution for disposal of waste from foundries.
Nil Waste Process Evolution for a Low Grade LimestoneIRJET Journal
This document summarizes research on developing a nil waste process for beneficiating a low-grade limestone using reverse cationic flotation.
The limestone sample contained mainly calcite and quartz and was analyzed to contain 45% CaO and 80% total carbonates. Grinding and flotation tests were conducted varying parameters like mesh of grind, collector type and dosage. The optimum conditions found were a mesh of grind of D80 400 microns, using 0.4 kg/t of cationic collector SOKEM565C. This produced a cement-grade concentrate assaying 90% total carbonates at an 88% weight yield. The non-float fraction assaying 80.30% Al
IRJET- Evaluation of Compressive Strength of Mortars Containing Stone Dust as...IRJET Journal
This document presents the results of a study that evaluated the compressive strength of mortar mixes containing stone dust as a partial replacement for river sand. Mortar cubes were prepared with 0%, 25%, and 50% replacements of sand by stone dust. The cubes were tested for compressive strength at 3, 7, and 28 days. The results showed that mortar mixes with up to 50% replacement of sand with stone dust met the minimum compressive strength standards. Therefore, the study concluded that stone dust can partially replace river sand in mortar mixes without negatively affecting compressive strength.
Recent growth of construction
industry has increased the demand of cement.
Increase of the cement utilization demands for
higher production efficiency and ultimately low
production cost. The efficiency of the cement
production depends greatly upon the efficiency of
a grinding mill which consumes 60-70% of the
total electricity consumption of the cement
plant[12]. A grinding mill (Ball Mill) is used to
grind the cement clinker into fine cement powder.
Grinding Aids are used to improve the grinding
efficiency and reduce power consumption. This
paper discusses the grinding aids mechanism and
improvement in grinding efficiency due to various
grinding aids viz .polyols, amines . This paper also
focus on the effects of grinding aids on the
mechanical properties of cement such as setting
time, specific surface, compressive strength at various ages.
Debranning has the aim to remove the outer layers of the pericarp from wheat kernels (Figure 1). Increasing number of industrial and research studies reports the advantages of debranning Durum wheat prior to milling:
Effect on Compressive and Tensile Strength of Cement Concrete Road Pavements ...IRJET Journal
This document summarizes a study on using iron ore tailings to partially replace fine aggregate in cement concrete used for road pavements. Concrete cubes and cylinders were cast with 0-50% replacement of sand with iron ore tailings. Compressive and flexural strength were tested at 7, 21, and 28 days. Results showed that compressive and flexural strength increased up to 30-40% replacement, but then started decreasing at 50% replacement. The study concluded that iron ore tailings can effectively replace a portion of fine aggregate in concrete, improving utilization of this waste material without compromising strength.
IRJET- Experimental Investigation on Partial Replacement of Rice Husk Ash as ...IRJET Journal
The document experimentally investigates the use of rice husk ash as a partial cement replacement and coconut shell as a partial coarse aggregate replacement in producing lightweight concrete. Seven concrete mixes were prepared with coconut shell replacing conventional aggregates at 0%, 5%, 10%, 15%, 20%, and 25% and rice husk ash kept constant at 10% cement replacement. The mechanical and durability properties of the mixes were then evaluated. The results showed that the mix with 10% rice husk ash and 10% coconut shell replacement provided good mechanical properties while also offering the advantages of utilizing waste materials and reducing natural resource depletion, suggesting coconut shell could be a feasible aggregate replacement in concrete production.
This document discusses optimizing cement grinding circuits through pre-crushing of clinker using a Barmac crusher prior to grinding in a two-compartment ball mill. Bond calculations and population balance modeling are used to analyze the potential benefits. Modeling suggests the total energy consumption for grinding can be reduced up to 10% by pre-crushing clinker to a finer size before ball milling. A case study of a cement plant found pre-crushing could lower the required ball mill power by 9-15% and increase grinding circuit capacity with relatively low capital investment compared to alternatives like high-pressure grinding rolls.
An Investigation on Strength and Durability of Cement Concrete Partially Repl...IRJET Journal
This document investigates using granite slurry as a partial replacement for cement in concrete. Granite slurry is a waste material from rock quarrying and crushing. The study tested concrete mixtures with 5-20% cement replacement using granite slurry under 75 microns. Tests found compressive and flexural strength were maintained with up to 10% replacement after 28 days. Higher replacements showed strength decreases. The study concluded granite slurry can be used for partial cement replacement, providing both economic and environmental benefits by reducing costs and waste. Up to 5% replacement provided optimal strength properties.
IRJET- Studies on Geopolymer Concrete with GGBS as Partial Replacement to...IRJET Journal
This document presents a study on geopolymer concrete with ground granulated blast furnace slag (GGBS) as a partial replacement for fly ash. Various mixtures of geopolymer concrete were prepared by replacing fly ash with GGBS at percentages from 0% to 100%. Sodium silicate and sodium hydroxide solutions at molarities of 8M, 10M and 12M were used as alkaline activators. Specimens were oven cured and tested for mechanical properties like compressive strength, flexural strength, and split tensile strength at 14 and 28 days. Test results showed that mechanical properties were highest for a mixture with 12M alkaline activator concentration and 100% GGBS replacement of fly ash. The
This thesis developed a virtual environment for simulating cone crusher performance using the discrete element method (DEM). Industrial scale experiments were conducted on a Svedala H6000 cone crusher to collect pressure, power and particle size data. The crusher liner geometries were 3D scanned. Two DEM simulations were performed using a bonded particle model to represent rock breakage. The first simulation did not match experiments well but the second, using a closer setting, showed good agreement with experimental pressure and throughput values, validating the DEM model. Further work is needed to calculate particle size distributions from the unbroken clusters.
IRJET- An Experimental Study on Performance of Ternary Blended High Strength ...IRJET Journal
This study experimentally investigates the performance of ternary blended high strength fiber reinforced concrete. Various mixtures were tested by replacing cement with ground granulated blast furnace slag and metakaolin at different percentages, and adding steel and glass fibers at amounts up to 2% by weight. The results showed that ternary blended fiber reinforced concrete exhibited higher compressive strength, tensile strength, and improved stress-strain behavior compared to normal concrete without additions.
IRJET-Experimental Study on Corn Cob Ash Powder as Partial Replacement of Cem...IRJET Journal
1) The study experimentally evaluates using corn cob ash (CCA) as a partial replacement for cement in concrete. Various percentages (0%, 10%, 20%, 30%) of CCA replacement were tested.
2) Results showed that compressive, flexural, and split tensile strengths were initially lower for CCA concrete but surpassed the control concrete at later ages, indicating the pozzolanic effect of CCA over time.
3) The 10% CCA replacement mixture achieved higher strengths at 90 days compared to the control, suggesting 10% CCA is a suitable partial replacement for cement.
IRJET- An Experimental Study on Strength of Concrete with Partial Replacement...IRJET Journal
This document presents an experimental study on using copper slag and quarry dust as partial replacements for fine aggregate in concrete. Various concrete mixes were tested with copper slag and quarry dust replacements ranging from 0-45%. Specimens were cured for 7-28 days and tested for compressive, split tensile, and flexural strengths. The results showed that concrete with a 40% fine aggregate replacement achieved the highest compressive strength of 41.87 MPa. Split tensile strengths were also higher than the control mix for replacements up to 15%. Thus, the study demonstrates that using industrial wastes like copper slag and quarry dust as partial replacements for fine aggregate in concrete can improve strength properties while providing environmental and economic benefits.
Laboratory Investigation of Conventional Asphalt Mix Using Shell Thiopave for...IJERA Editor
The characteristic performance of asphalt pavement always depends on the properties of bitumen, volumetric properties of asphalt mixtures. Bitumen is visco– elastic material where the temperature and rate of load application have a great influence on its behavior. There are different solutions to reduce the pavement distress such as using Thiopave (binder extender and asphalt mixture modifier) in the mix design. Thiopave can significantly alter the performance properties of the mix and it is helpful to extend the life span of pavement. In this study, investigating use of thiopave and the change in the performance properties is dependent both on the percentage of virgin binder using VG-30 bitumen that is substituted with thiopave with different percentages. The study indicated that 10%, 20%, 30% and 40% replacement of binder was done with thiopave. The most notable impact of the addition of thiopave to a bituminous mixture is an increase in the stiffness of the mixture for better resistance to fatigue cracking and rutting. Thiopave materials can have a positive impact on laboratory mixture performance. The addition of thiopave has been shown to significantly increase Marshall Stability. From this study it is observed that thiopave can be utilized up to 30% to 40% as replacement to bitumen.
The document describes an XRT intelligent ore sorter that uses X-ray technology and sensors to identify and separate ore from waste rock. It has the highest precision and can process the largest range of particle sizes of any raw ore sorting equipment. The sorter improves mining efficiency by increasing ore grades, reducing waste, and allowing for recovery from tailings and slag. It has applications in sorting a wide variety of metal and non-metal ores.
Xrt x ray transmission ore sorter intelligent dry separation-hot mining_serenaSerena Fu
The document describes an XRT intelligent dry sorter produced by Beijing Hot Mining Tech Co Ltd. It has the highest precision, can process the largest particle sizes, and is the most stable system. The sorter uses X-ray technology and AI algorithms to sort raw ore, improving ore grades and reducing waste. It has applications in mining a variety of minerals like gold, silver, and copper. The sorter provides benefits like lower processing costs, improved efficiency and profits, and extended mine life.
Application Prospect of XRT Intelligent X-ray Transmission Ore Sorter for Dry...Serena Fu
HOT Mining XRT X-ray transmission intelligent ore sorter is a very good dry separation choice for pre-concentration of run-of-mine and discard ores, including but not limited to coal, gold, copper, lead-zinc, tungsten, antimony and etc. It can not only improve recovery efficiency, but also reduce unit production cost at the same time.
This document provides information on industrial cleaning equipment from Nido Machineries Pvt. Ltd., including specifications for various products. The document includes sections on vacuum cleaners, sweepers, scrubbers, scrubber dryers, aerial work platforms, outdoor sweeper attachments, high pressure washers, authorized dealers, and exclusive partnerships. Product lines cover economy, performance, and industrial ranges. Information provided includes model names and numbers, capacities, dimensions, power ratings, and intended applications.
The document discusses CAD/CAM systems used in dentistry. It begins by defining CAD as using computers to create or modify designs, and CAM as using computers to automate manufacturing processes. CAD/CAM systems digitally scan teeth, use software to design restorations, and mill restorations from materials like ceramics, metals, and resins. The document describes various CAD/CAM systems, materials, milling techniques, and advantages of the technology for producing dental restorations with greater accuracy and efficiency compared to traditional methods.
This slide contains theoritical and analytical study about "about abrasive water jet machining process" and it has also discription about " OMAX 60120 abrasive water jet machine.Here analytical stydy is done with mainly ss-304 material.
Sahajanand Laser Technology Ltd. (SLTL Group) is the
largest manufacturer of laser systems in India and world's
first manufacturer of fiber laser cutting machine for sheet
metal application such as Laser cutting, Marking, Welding,
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Pioneering Large Diamond Recovery at Karowe Diamond Mine_Ref Comments_11-12-2015
1. PIONEERING LARGE DIAMOND RECOVERY AT
KAROWE DIAMOND MINE
ABSTRACT
Historically, large diamond recovery in conventional treatment plant flowsheets has been associated
with dense media separation (DMS) as an ore beneficiation technique. This is mainly attributed to its
highly efficient and proven track record as a successful method in the concentration and separation of
ores with variable solids densities. In most instances, dense media separation has been recognised and
utilised as a pre-concentration step ahead of any Recovery plant due to its ability and versatility in
reducing DMS feed ore within a specific size range to manageable volumes required for downstream
X-Ray processing and subsequent diamond recovery. The benefit of using carbon signature based
detection equipment in retrieving large stones upfront in the flowsheet not only equates to earlier
beneficiation of diamonds from the system, but also promotes the reduction of diamond-bearing ore
exposure to additional materials handling, pumping and/or crushing which has been known to damage
or even break product and decrease revenue as part of the overall value chain.
INTRODUCTION
The selection of X-ray transmission (XRT) for kimberlite sorting lies in the advantage of the material
presentation. Detection with XRT is dependent on the atomic number of the material to be the detected.
The sorting ability and effectiveness of X-ray transmission lies in variance of the atomic number of
material A and B that need to be separated from each other. The advantage of this technique is that the
presentation of the material is of lesser importance. Unlike Near-Infrared (NIR) and X-ray
Luminescence (XRL), XRT is not dependant on a clean, visibly colour different or reflective particle
surfaces. XRT technology has a significantly higher detection of Type II diamonds compared to
traditional XRL sorters with an order of magnitude lower yield percentage. XRT sorters delivers a
significantly lower percentage yield than traditional DMS plants with a vastly reduced running cost
relating to consumables and utilities.
Figure 1: Sensor technology applications
2. A broad-band electrical X-ray source is applied to the material to be sorted while it is moving along the
belt.
Figure 2: XRT sorter material discrimination
The X-ray sensor system below the material produces a digital image of the material being sorted, using
two different energy bands. The X-ray attenuation through the material is different between the two
bands and depends on both the material's thickness and density. An image transformation of the density
images of the two bands then enables the classification of each pixel according to its average atomic
density.
Figure 3: Dual XRT sensing
Figure 4: XRT imaging
3. Figure 5: XRT automated sorting principle
Classification of each pixel proceeds relative to a reference density against which the system has been
calibrated. A complete particle will then be classified according to the overall classification of the pixels
within the particle. Depending on the classification, the selected particles are either “ejects”, diverted
upwards by air jets out of the overall material stream (material stream B) or “accepts” in the other stream
(material stream A). It is important to note that “eject” refers to the material that the system has been
configured to blow out of the material stream, this can be either the waste or the product.
XRT CIRCUIT DESIGN, COMMISSIONING & PERFORMANCE
XRT Layout (including Audit XRT): The Karowe XRT section, as part of the greater Karowe Plant
Upgrade circuit, is found post autogenous (AG) milling where a DMS/Bulk Sorter Sizing Screen is
utilised to separate the XRT feed envelope from the -8 mm DMS feed and also any -1.5 mm fine effluent
generated in the circuit due to particle breakdown via materials handling, transfers and recycling.
The DMS/Bulk Sorter Sizing Screen is key to the circuit in Figure 6 due to its central positioning in
receiving milled ore, tertiary crusher product and also pebble crusher “bleed” fraction (i.e. pebble
crusher recycle by-pass not re-directed back to mill feed for load management requirements). From the
DMS/Bulk Sorter Sizing Screen, the feed is split into the following three streams:
• -60 +8 mm fraction is wet screened and fed to the XRT section.
• -8 +1.5 mm fraction is wet screened and fed to the existing DMS for gravity concentration.
• -1.5 mm envelope is removed as effluent to the degrit circuit for grits removal and dewatering
purposes. There is little to no value in the effluent stream hence the reason for removal and
dewatering.
Moving away from the DMS/Bulk Sorting Sizing Screen and down to the XRT section, the -60 +8 mm
is further separated via Bulk Sorter Sizing Screen at the top of the XRT building into the following
streams:
• Large Diamond Recovery (x 1 stream) -60 +32 mm
• Coarse XRT (x 2 streams) -32 +14 mm
• Middles XRT (x 2 streams) -14 +8 mm
5. Figure 8: Karowe’s XRT section during construction (Q2 2015)
To recover large diamonds in the various XRT size fractions as set out above, each individual size
fraction stream’s processing route utilises bin(s) and variable speed belt feeder(s) to “match” each
associated XRT’s size-specific throughput application. Feed presentation ahead of each XRT machine
was a critical factor evaluated during the design phase: a vibrating feeder ahead of the XRT machine
accepts feed from the upstream belt feeder and introduces an evenly distributed mono layer feed to the
XRT feed belt typically running at speeds of up to ~3 m/s. The following table below best illustrates the
throughput-size fraction relationship applicable to Karowe’s Bulk Sorting section:
Table I: XRT Throughput vs size fraction treatment
Maximum Machine Throughput – Karowe Plant Specific
Description Size Fraction Throughput (tph)
Large Diamond Recovery
(LDR) XRT Bulk Sorting
-60 +32 mm 150
Coarse XRT Bulk Sorting -32 +14 mm 100
Middles XRT Bulk Sorting -14 +8 mm 60
Feed moisture content (percentage solids by weight) from upstream washing/sizing was also
instrumental to the design, as any value in excess of 8 percent surface moisture (by weight) will cause
unnecessary fines build-up in the Bulk Sorting section and detrimentally impact on machine
performance. Supporting utility services were also crucial for each and every XRT performing to its
optimum efficiency; by utilising compressed air and chilled water as essential services to the machines,
diamond concentrate could be adequately “ejected” from each sized stream with chiller water
effectively cooling down the respective x-ray tubes for continuous successful operation. Tables II and
III capture the chiller water and compressed air services data. The data were required during design
and subsequent operation of the Karowe XRT sorter machines.
6. Table II: Chiller water requirements per Karowe XRT sorter
Description Value / Comment
Water Circuit Flowrate (l/min) 10
Water Pressure at Machine Inlet (bar) 4.5
Maximum Operating Temperature (˚C) 40
Water Inlet Temperature (˚C)
(Chiller pipes require isolation lagging to keep fluid temperature
down to a minimum before feed entry into machines)
25
Cooling Capacity Required (kW, accumulated heating energy)
4 kW X-Ray Source
4 kW Generator
8
Coolant
High Glycol content;
≤ 10 percent concentration
Table III: Consumed air requirements per tonne of feed ejected
Description Value
Large Diamond Recovery (LDR) XRT Bulk Sorting (m3/hr)
20
(Based on 1% material ejection rate)
Coarse XRT Bulk Sorting (m3/hr)
25
(Based on 1% material ejection rate)
Middles XRT Bulk Sorting (m3/hr)
50
(Based on 1% material ejection rate)
Cold commissioning (C3) with regards to the Karowe XRT machines were completed on the 15th of April
2015. These included the following vendor-specific activities:
• Splicing of new sorter belts.
• Electrical wiring of the sorters.
• Sorter calibrations and sorting algorithms.
• Tracer testing without material.
• Diamond testing without material.
During the tracer and diamond testing without material, the following tracer and diamond quantities
with associated specifications were adopted and utilised to calibrate, set up and test individual machine
performances. Aspects requiring set up and testing included white balance, nozzle to pixel mapping,
divergence, and establishing the various calibration curves.
Table IV: Karowe XRT tracer and diamond specifications used during cold commissioning
Material Size Fraction (mm)
Number & of Cubic
Carbon Tracers Used
Tracer
Dimensions (mm)
Minimum Diamond
Size Range (mm)
LDR: -60 +32 mm
@ 150 tph
500 @ 98% expected
recovery
50 x 50 x 50
24.26 x 20.12 x 24.12
(tracer diamond #52)
Coarse: -32 +14 mm
@ 100/200 tph
(Throughput per sorter /
Overall throughput)
500 @ 98% expected
recovery
15 x 15 x 15
11.14 x 11.03 x 9.51
(tracer diamond #25)
Middles: -14 +8 mm
@ 43/86 tph
(Throughput per sorter /
Overall throughput)
500 @ 98% expected
recovery
10 x 10 x 10
6.54 x 6.83 x 6.99 (tracer
diamond #52)
Following the cold commissioning activities that concluded on the 15th of April, the project moved into
a hot commissioning phase (C4) with the following listed activities that occurred soon after:
7. • Tracer testing with material feed.
• Production ramp-up.
• Production optimisation.
Tracer results obtained during hot commissioning of the XRT sorters can be viewed in Tables V to IX.
Table V: Karowe LDR (-60 +32 mm) XRT sorter tracer test results
Tracer Test No.
Totaliser
Start
(tonnes)
Totaliser
Stop
(tonnes)
Tonnes Treated
during Tracer
Test
Number of
Tracers added
to Ore Feed
% Tracer
Recovery
1 5.8 14.0 8.2 100 100
2 14.0 26.2 12.2 100 100
3 26.2 33.9 7.7 100 100
4 33.9 46.5 12.6 100 100
5 46.5 54.3 7.8 100 100
Total / Average - - 48.5 (total) 500 (total)
100
(average)
Average Throughput Range during
all Tracer Test Runs (tph)
100 – 153
% VSD Setting on Belt Feeder
Feeding XRT Sorter
20 (Tests 1, 2) & 38 – 42 (Tests 3, 4 & 5)
Table VI: Karowe Coarse 1 (-32 +14 mm) XRT sorter tracer test results
Tracer Test No.
Totaliser
Start
(tonnes)
Totaliser
Stop
(tonnes)
Tonnes Treated
during Tracer
Test
Number of
Tracers added
to Ore Feed
% Tracer
Recovery
1 12.4 18.6 6.2 100 100
2 18.6 24.1 5.5 100 100
3 24.1 29.0 4.9 100 100
4 29.0 33.6 4.6 100 100
5 33.6 37.4 3.8 100 100
Total / Average - - 25.0 (total) 500 (total)
100
(average)
Average Throughput Range during
all Tracer Test Runs (tph)
100 – 120
% VSD Setting on Belt Feeder
Feeding XRT Sorter
25
Table VII: Karowe Coarse 2 (-32 +14 mm) XRT sorter tracer test results
Tracer Test No.
Totaliser
Start
(tonnes)
Totaliser
Stop
(tonnes)
Tonnes Treated
during Tracer
Test
Number of
Tracers added
to Ore Feed
% Tracer
Recovery
1 3.0 8.8 5.8 100 100
2 8.8 13.8 5.0 100 100
3 13.8 18.6 4.8 100 100
4 18.6 24.8 6.2 100 100
5 24.8 29.4 4.6 100 100
Total / Average - - 26.4 (total) 500 (total)
100
(average)
Average Throughput Range
during all Tracer Test Runs (tph)
90 – 130
% VSD Setting on Belt Feeder
Feeding XRT Sorter
25
8. Table VIII: Middles 1 (-14 +8 mm) XRT sorter tracer test results
Tracer Test No.
Totaliser
Start
(tonnes)
Totaliser
Stop
(tonnes)
Tonnes
Treated
during Tracer
Test
Number of
Tracers added
to Ore Feed
% Tracer
Recovery
1 34.8 38.3 3.5 100 100
2 38.3 41.0 2.7 100 98
3 41.0 44.3 3.3 100 100
4 44.3 47.0 2.7 100 100
5 47.0 49.4 2.4 100 99
Total / Average - - 14.6 (total) 500 (total)
99.4
(average)
Average Throughput Range
during all Tracer Test Runs
(tph)
40 – 43
% VSD Setting on Belt Feeder
Feeding XRT Sorter
13
Table IX: Karowe Middles 2 (-14 +8 mm) XRT sorter tracer test results
Tracer Test No.
Totaliser
Start
(tonnes)
Totaliser
Stop
(tonnes)
Tonnes Treated
during Tracer
Test
Number of
Tracers added
to Ore Feed
% Tracer
Recovery
1 46.9 50.9 1.3 100 100
2 50.9 52.1 1.2 100 100
3 52.1 53.3 1.2 100 99
4 53.3 54.6 1.3 100 100
5 54.6 55.8 1.2 100 100
Total / Average - - 6.2 (total) 500 (total) 99.8 (average)
Average Throughput
Range during all Tracer
Test Runs (tph)
41 – 44
% VSD Setting on Belt
Feeder Feeding XRT
Sorter (on SCADA)
13
Average yields achieved during above tracer tests in material feed were in the order of ~ 1.3 to
8.0 x 10-5 % with an associated calculated product yield range of ~0.3 to 1.2 kg/day. Hot commissioning
ceased on the 27th of April 2015 where the XRT sorters were subsequently handed over to the Boteti
client for normal production running. Continued production performance monitoring also occurred
post XRT handover for another period of 28 days until this was completed on the 25th of May 2015.
Further XRT optimisation was required and completed on the challenges experienced post production
running. These challenges were:
• Low air consumption and air inlet pressure: mitigating action involved separating the LDR XRT
separator from the rest of the XRT compressed air circuit with its own dedicated stand-alone
compressor unit.
• Low chiller water inlet flow: matter resolved on site through small system adjustment.
• Occasional fines carry-over from DMS/Bulk Sorter Sizing Screen: this was alleviated by optimising
the spray and wash water requirements associated upstream with the DMS/Bulk Sorter Sizing
Screen.
On 18 November 2015, Karowe mine made history when Lucara Diamond Corporation reported the
recovery of an 1111 carat, white Type IIa stone weighing 222 grams and measuring 65 mm x 56 mm x
40 mm. This is the second largest gem quality stone in history – beaten only by the massive Cullinan
9. diamond discovered in 1905 and weighing 3106 carats. Karowe mine also recovered an 813 carat, white
Type IIa diamond soon after the 1111 carat find - which is the sixth largest gem quality stone also ever
recovered.
FUTURE XRT UPGRADES ENVISAGED AT KAROWE MINE
Due to the prevalence of very large diamonds at Karowe, the mine has opted to evaluate the possibility
of a very large diamond recovery (VLDR) section close to the current secondary crushing area. A
potential design is to investigate keeping the sorting and comminution aspects separate from a process
perspective so that the undersize scalping associated with comminution purposes can be changed
independently of the VLDR sorter. In a nutshell, a proposed design will consider:
• All primary crusher ROM product to be scalped at 60 or even 50 mm with the -60/50 mm undersize
reporting directly to the AG mill.
• Inclusion of a 125 mm grizzly screen ahead of secondary crushing to treat the oversize fraction from
the scalping screen: with the -125 +50 mm middles envelope directed to the VLDR sorter(s) for
diamond recovery.
• Tailings from the new VLDR sorter(s) will subsequently recombine with the +125 mm grizzly
oversize material and subjected to the existing proportional splitter ahead of the secondary crushing
section: undergoing the same crusher/bypass operational split flexibility of 25, 50, or 75 % as is
currently the case.
REFERENCES
Riedel, F., Dehler, M. (2010). Recovery of unliberated diamonds by X-ray transmission sorting.
Proceedings of the fourth Diamonds: Source to Use Conference. The South African Institute of Mining and
Metallurgy. Gaborone, Botswana. pp. 193-200.
Von Ketelhodt, L. (2012). Tomra Sorting Solutions. Regional Meeting. The South African Institute of Mining
and Metallurgy. Johannesburg. South Africa. Presentation.
Van Niekerk, L.M., Ndlovu, G.N., Sikwa, N.A. (2013). Commissioning and Operating an Autogenous
Mill at Karowe Diamond Mine. Proceedings of the fifth Diamonds: Source to Use Conference. The South
African Institute of Mining and Metallurgy. Muldersdrift, South Africa. pp. 175-192.
Morgan, P., Van Niekerk, L.M., Underwood, G., Paz, A. (2015). Introduction of Turbo-lifter System at
Karowe Diamond Mine & Comminution Circuit Upgrade. Proceedings of the Sixth International Conference
on Semi-autogenous & High Pressure Grinding Technology. Vancouver, Canada. Extended abstract for
poster presentation.
Financial Post. (2015). Canadian miner Lucara finds 1,111-carat diamond – believed to be second largest
ever.
http://business.financialpost.com/news/mining/canadian-miner-lucara-uncovers-1111-carat-
diamond-believed-to-be-second-largest-ever-found [accessed 14 Dec. 2015].
ACKNOWLEDGEMENTS
The authors are grateful to the following individuals:
• William Lamb, Lucara Diamond Corp;
• Paul Day, Lucara Diamond Corp;
• Gerald Ndlovu, Boteti Mining;
• John Maketo, Boteti Mining;
10. • Boteti Process, Lab and Security teams;
• Fabien Riedel, Tomra Sorting Solutions;
• Geoffrey Madderson, Tomra Sorting Solutions;
• Gavin Underwood, Minopex Botswana;
• Paul Morgan, DRA Mineral Projects;
• Matthew Duddy, DRA Mineral Projects;
• Bennie Viljoen, DRA Mineral Projects;
• Reuben Moalosi, DRA Mineral Projects;
• Cornelius Ntsomeng, DRA Mineral Projects;
• Gavin Outhwaite, DRA Mineral Projects;
• DRA Construction and Commissioning teams.