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Drop weight tests (DWT) and rubber wheel abrasion tests (RWAT) were carried out on an ore containing haematite and quartz and a synthetic ore containing grout, epoxy and glass beads. The data were fitted to the parameters of the t(10)) model, where t(10) represents particles finer than one tenth of their particle size and is related to specific communication energy using an equation which includes the curve fitting parameters A and b. The product of A and b can be used to provide a single measure of the resistance to breakage by impact for a reasonable broad range of particle sizes. The t(10) model curves were also obtained from dry SWAT tests by finding the A and b values which minimise the least square of the objective function using Excel solver routines. Comparison of the A and b values for the two types of test showed considerable differences due to the large rocks and pebbles used in DWT and the small granular ores in SWAT. A modified t(10) model taking into account particle size was applied to the dry SWAT results and showed improved predictability. SWAT results obtained under wet conditions were fitted to the modified t(10) model and the model fitted the data more suitably than under dry conditions. The specific rate of breakage values were higher than for dry grinding. The SWAT results showed that the t(10) model can be fitted to data obtained from experimental tests using the modified t(10) model. SWAT requires significantly less test material than DWT., Drop weight tests (DWT) and rubber wheel abrasion tests (RWAT) were carried out on an ore containing haematite and quartz and a synthetic ore containing grout, epoxy and glass beads. The data were fitted to the parameters of the t(10)) model, where t(10) represents particles finer than one tenth of their particle size and is related to specific communication energy using an equation which includes the curve fitting parameters A and b. The product of A and b can be used to provide a single measure of the resistance to breakage by impact for a reasonable broad range of particle sizes. The t(10) model curves were also obtained from dry SWAT tests by finding the A and b values which minimise the least square of the objective function using Excel solver routines. Comparison of the A and b values for the two types of test showed considerable differences due to the large rocks and pebbles used in DWT and the small granular ores in SWAT. A modified t(10) model taking into account particle size was applied to the dry SWAT results and showed improved predictability. SWAT results obtained under wet conditions were fitted to the modified t(10) model and the model fitted the data more suitably than under dry conditions. The specific rate of breakage values were higher than for dry grinding. The SWAT results showed that the t(10) model can be fitted to data obtained from experimental tests using the modified t(10) model. SWAT requires significantly less test material than DWT.

The abrasion wheel test used to determine the contribution of abrasive wear and friction to the total wear of steel grinding media provides an opportunity to study ore breakage as well. Tests were carried out using standard Ottawa foundry sand. It is shown that the abrasive wheel test produces fine particles, that it can be used to determine the operating work index, the locked cycle work index and the t10 function for a given ore, that the amount of prepared ore to determine the breakage parameters varies with the test method used, that in conjunction with these tests steel media abrasive wear and friction can be determined, and that all test results indicate a relationship between steel wear, friction, and abrasive ore breakage. Implications of the work and further directions it may take are considered., The abrasion wheel test used to determine the contribution of abrasive wear and friction to the total wear of steel grinding media provides an opportunity to study ore breakage as well. Tests were carried out using standard Ottawa foundry sand. It is shown that the abrasive wheel test produces fine particles, that it can be used to determine the operating work index, the locked cycle work index and the t10 function for a given ore, that the amount of prepared ore to determine the breakage parameters varies with the test method used, that in conjunction with these tests steel media abrasive wear and friction can be determined, and that all test results indicate a relationship between steel wear, friction, and abrasive ore breakage. Implications of the work and further directions it may take are considered.

A pilot scale microwave treatment system capable of treating 10-150t/h of material at 10-200kW was designed, constructed and commissioned in order to understand the engineering challenges of microwave-induced fracture of ores at scale and generate large metallurgical test samples of material treated at approximately 0.3-3kWh/t. It was demonstrated that exposing more of the ore to a region of high power density by improving treatment homogeneity with two single mode applicators in series yielded equivalent or better metallurgical performance with up to half the power and one third the energy requirement of that used with a single applicator. Comminution testing indicated that A*b values may be reduced by up to 7-14% and that the Bond Ball Mill Work Index may be reduced by up to 3-9% depending on the ore type under investigation. Liberation analysis of the microwave-treated ore indicated that equivalent liberation may be achievable for a grind size approximately 40-70µm coarser than untreated ore, which is in agreement with laboratory scale investigations reported in the literature at similar or higher doses. Flow sheet simulations further indicated that reduced ore competency following microwave treatment could potentially yield up to a 9% reduction in specific comminution energy (ECS) at a nominal plant grind of P₈₀190µm, or up to 24% reduction at a grind of P₈₀290µm, for a microwave energy input of 0.7-1.3kWh/t. Throughput could also be increased by up to approximately 30% depending on grind size, ore type and equipment constraints. To date, approximately 900t of material has been processed through the pilot plant, approximately 300t of which was under microwave power. Metallurgical testing has demonstrated that comminution and liberation benefits are achievable at doses lower than that previously reported in the literature, which allow high throughputs to be sustained with low installed power requirements providing a pathway to further scale-up of microwave treatm

A test apparatus was developed to replicate the squeezing wear present in many rock crushers and experiments were carried out using silica sand of different size fractions between 0.725 and 2.03 mm and varying crushing loads. The results showed that the wear rate increased as the particle size increased. The size distribution range also affected wear rate. An alternative wear model for cone crushers was derived in which the wear is proportional to particle size and to the square root of the pressure. Results from the model are in good agreement with experimental data., A test apparatus was developed to replicate the squeezing wear present in many rock crushers and experiments were carried out using silica sand of different size fractions between 0.725 and 2.03 mm and varying crushing loads. The results showed that the wear rate increased as the particle size increased. The size distribution range also affected wear rate. An alternative wear model for cone crushers was derived in which the wear is proportional to particle size and to the square root of the pressure. Results from the model are in good agreement with experimental data.

In order to determine the contribution of abrasive wear to total steel media wear in mills as a function of charge motion, it is necessary to determine abrasive wear as a function of applied force and slippage speed. A modified abrasion wheel testing apparatus was developed and used under dry conditions to determine the relationship between abrasive wear, applied force and friction. Four different ores from North American mines were examined where the test specimens used with each abrasive were cut from grinding media supplied by the corresponding mines. The results showed an initial increase in wear, as measured by the volume (mass) loss, with increasing applied force. The mass loss became constant beyond a certain applied force. The friction remained relatively constant for each ore/media combination over the test range., In order to determine the contribution of abrasive wear to total steel media wear in mills as a function of charge motion, it is necessary to determine abrasive wear as a function of applied force and slippage speed. A modified abrasion wheel testing apparatus was developed and used under dry conditions to determine the relationship between abrasive wear, applied force and friction. Four different ores from North American mines were examined where the test specimens used with each abrasive were cut from grinding media supplied by the corresponding mines. The results showed an initial increase in wear, as measured by the volume (mass) loss, with increasing applied force. The mass loss became constant beyond a certain applied force. The friction remained relatively constant for each ore/media combination over the test range.

This work investigated abrasive friction and wear of steel media as a function of the energies/forces acting in abrasion in a given mill. A test was developed based on the ASTM G65 abrasive wheel test, with Ottawa foundry sand as the abrasive medium and the steels tested 1018 and 1045., This work investigated abrasive friction and wear of steel media as a function of the energies/forces acting in abrasion in a given mill. A test was developed based on the ASTM G65 abrasive wheel test, with Ottawa foundry sand as the abrasive medium and the steels tested 1018 and 1045.

A pilot scale microwave treatment system capable of treating 10-150t/h of material at 10-200kW was designed, constructed and commissioned in order to understand the engineering challenges of microwave-induced fracture of ores at scale and generate large metallurgical test samples of material treated at approximately 0.3-3kWh/t. It was demonstrated that exposing more of the ore to a region of high power density by improving treatment homogeneity with two single mode applicators in series yielded equivalent or better metallurgical performance with up to half the power and one third the energy requirement of that used with a single applicator. Comminution testing indicated that A*b values may be reduced by up to 7-14% and that the Bond Ball Mill Work Index may be reduced by up to 3-9% depending on the ore type under investigation. Liberation analysis of the microwave-treated ore indicated that equivalent liberation may be achievable for a grind size approximately 40-70µm coarser than untreated ore, which is in agreement with laboratory scale investigations reported in the literature at similar or higher doses. Flow sheet simulations further indicated that reduced ore competency following microwave treatment could potentially yield up to a 9% reduction in specific comminution energy (ECS) at a nominal plant grind of P₈₀190µm, or up to 24% reduction at a grind of P₈₀290µm, for a microwave energy input of 0.7-1.3kWh/t. Throughput could also be increased by up to approximately 30% depending on grind size, ore type and equipment constraints. To date, approximately 900t of material has been processed through the pilot plant, approximately 300t of which was under microwave power. Metallurgical testing has demonstrated that comminution and liberation benefits are achievable at doses lower than that previously reported in the literature, which allow high throughputs to be sustained with low installed power requirements providing a pathway to further scale-up of microwave treatm

A pilot scale microwave treatment system capable of treating 10-150t/h of material at 10-200kW was designed, constructed and commissioned in order to understand the engineering challenges of microwave-induced fracture of ores at scale and generate large metallurgical test samples of material treated at approximately 0.3-3kWh/t. It was demonstrated that exposing more of the ore to a region of high power density by improving treatment homogeneity with two single mode applicators in series yielded equivalent or better metallurgical performance with up to half the power and one third the energy requirement of that used with a single applicator. Comminution testing indicated that A*b values may be reduced by up to 7-14% and that the Bond Ball Mill Work Index may be reduced by up to 3-9% depending on the ore type under investigation. Liberation analysis of the microwave-treated ore indicated that equivalent liberation may be achievable for a grind size approximately 40-70µm coarser than untreated ore, which is in agreement with laboratory scale investigations reported in the literature at similar or higher doses. Flow sheet simulations further indicated that reduced ore competency following microwave treatment could potentially yield up to a 9% reduction in specific comminution energy (ECS) at a nominal plant grind of P₈₀190µm, or up to 24% reduction at a grind of P₈₀290µm, for a microwave energy input of 0.7-1.3kWh/t. Throughput could also be increased by up to approximately 30% depending on grind size, ore type and equipment constraints. To date, approximately 900t of material has been processed through the pilot plant, approximately 300t of which was under microwave power. Metallurgical testing has demonstrated that comminution and liberation benefits are achievable at doses lower than that previously reported in the literature, which allow high throughputs to be sustained with low installed power requirements providing a pathway to further scale-up of microwave treatm

A pilot scale microwave treatment system capable of treating 10-150t/h of material at 10-200kW was designed, constructed and commissioned in order to understand the engineering challenges of microwave-induced fracture of ores at scale and generate large metallurgical test samples of material treated at approximately 0.3-3kWh/t. It was demonstrated that exposing more of the ore to a region of high power density by improving treatment homogeneity with two single mode applicators in series yielded equivalent or better metallurgical performance with up to half the power and one third the energy requirement of that used with a single applicator. Comminution testing indicated that A*b values may be reduced by up to 7-14% and that the Bond Ball Mill Work Index may be reduced by up to 3-9% depending on the ore type under investigation. Liberation analysis of the microwave-treated ore indicated that equivalent liberation may be achievable for a grind size approximately 40-70µm coarser than untreated ore, which is in agreement with laboratory scale investigations reported in the literature at similar or higher doses. Flow sheet simulations further indicated that reduced ore competency following microwave treatment could potentially yield up to a 9% reduction in specific comminution energy (ECS) at a nominal plant grind of P₈₀190µm, or up to 24% reduction at a grind of P₈₀290µm, for a microwave energy input of 0.7-1.3kWh/t. Throughput could also be increased by up to approximately 30% depending on grind size, ore type and equipment constraints. To date, approximately 900t of material has been processed through the pilot plant, approximately 300t of which was under microwave power. Metallurgical testing has demonstrated that comminution and liberation benefits are achievable at doses lower than that previously reported in the literature, which allow high throughputs to be sustained with low installed power requirements providing a pathway to further scale-up of microwave treatm

A pilot scale microwave treatment system capable of treating 10-150t/h of material at 10-200kW was designed, constructed and commissioned in order to understand the engineering challenges of microwave-induced fracture of ores at scale and generate large metallurgical test samples of material treated at approximately 0.3-3kWh/t. It was demonstrated that exposing more of the ore to a region of high power density by improving treatment homogeneity with two single mode applicators in series yielded equivalent or better metallurgical performance with up to half the power and one third the energy requirement of that used with a single applicator. Comminution testing indicated that A*b values may be reduced by up to 7-14% and that the Bond Ball Mill Work Index may be reduced by up to 3-9% depending on the ore type under investigation. Liberation analysis of the microwave-treated ore indicated that equivalent liberation may be achievable for a grind size approximately 40-70µm coarser than untreated ore, which is in agreement with laboratory scale investigations reported in the literature at similar or higher doses. Flow sheet simulations further indicated that reduced ore competency following microwave treatment could potentially yield up to a 9% reduction in specific comminution energy (ECS) at a nominal plant grind of P₈₀190µm, or up to 24% reduction at a grind of P₈₀290µm, for a microwave energy input of 0.7-1.3kWh/t. Throughput could also be increased by up to approximately 30% depending on grind size, ore type and equipment constraints. To date, approximately 900t of material has been processed through the pilot plant, approximately 300t of which was under microwave power. Metallurgical testing has demonstrated that comminution and liberation benefits are achievable at doses lower than that previously reported in the literature, which allow high throughputs to be sustained with low installed power requirements providing a pathway to further scale-up of microwave treatm