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1

Estimation of grade and recovery in the concentration of barite tailings by the flotation using the MLR and ANN analyses

Deniz Vedat, Umucu Yakup, Deniz Orcun T.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 150646

EN

This study aimed to find optimal models in a comparative framework to estimate the recovery and grade of barite concentrate obtained from the rougher flotation of the barite tailings. Therefore, firstly, the effect of four operating parameters (flotation time, pH, collector dosage, and depressant dosage) on the rougher flotation of the barite tailings containing 37.23% BaSO4 was experimentally investigated. Secondly, two models called the multivariable linear regression (MLR) and the artificial neural network (ANN) were used for the estimation of the recovery and grade of the barite concentrate for the rougher flotation optimization. The R2 values found from the MLR and ANN models were 0.828 and 0.995 for the concentrate recovery, and 0.977 and 0.960 for the barite concentrate grade, respectively. In the comparison of the models determined, it was found that the ANN model expressed quite well than the MLR models, especially for the recovery of the rougher concentrate.

2

Beneficiation and concentration of feldspar from syenite ore in Medina, Saudi Arabia for industrial utilization

Gougazeh Mousa

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 155056

EN

The objective of this study was to reduce the contents of iron and titanium heavy minerals of feldspar from Medina syenite ore by a combination of magnetic separation and flotation to obtain the commercial scale of feldspar concentrate for glass and ceramics industries. For the first time, a process flowchart was provided in the light of this study to produce a high-quality K-feldspar product from syenite ore, which meets the requirements of feldspar for glass and ceramics productions. The results reflect that the best performance separation of iron and titanium contents was produced by a dry magnetic separator at 16.000 gauss. The produced feldspar concentrate by magnetic separation yielding 0.54% Fe2O3 with 87% Fe2O3 recovery and 0.57% TiO2 with 16% recovery. The flotation tests were performed on the non-magnetic fraction of the syenite ore. In this stage, the most effective for removal of Fe2O3 and TiO2 from syenite ore was obtained at a 300 g/ton dosage of a mixture of Aeromine 3030C and Aeromine 801 + Aeromine 825 as a collector in an acidic medium (pH 3). The final feldspar concentrate with 0.07% Fe2O3 and 0.06%TiO2 grades was obtained with 89% Fe2O3 recovery and 86% TiO2 recovery. The commercial scale of feldspar concentrate from syenite ore can meet the desired specification of grades 1 and 2 for glass, porcelain, and ceramics industries.

3

Investigation of the frother effect in two and three phases systems on bubble size, surface tension, recovery and grade in chalcopyrite flotation

Ceylan Adnan, Bulut Gülay

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 6

23--35

EN

In this study, the effect of frother was investigated in two and three phases in the systems of the flotation. While the two-phase system consisted of liquid and gas, the three-phase systems contained a chalcopyrite ore. The study of three-phase systems was performed with the ore on a laboratory and plant scale. Effect of the amount and type of the frothers, their mixtures, and pH were examined depending on the bubble size, grade of the concentrate, and the recovery of chalcopyrite flotation. The results showed that as the amount of frothers increased, there was a reduction in the bubble size in all experiments. Additionally, the frother mixtures gave a positive effect on the chalcopyrite flotation. One of the most important purposes of flotation frothers shrinks the air bubble. As can be understood from the tests this time reduction of the frothers bubble size has a positive effect on the flotation. Likewise, it increases the foam stable value. It is observed from this study that increasing the amount of frothers decreases the surface tension and bubble size at different pH.

4

Grade impact investigation during stopping sight distance determination on 3D road environment

Mavromatis Stergios, Matragos Vassilios

Journal of Sustainable Development of Transport and Logistics

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2021

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Vol. 6, No. 1

72--80

EN

In the present research, Stopping Sight Distance (SSD) adequacy is assessed through a three-dimensional approach, which associates road visibility in terms of grade effect. SSD adequacy is controlled through the difference between the available and the required SSD. The research is focused on a right turned, two lane rural road, associated with a crest vertical curve for a given speed value. The road design is in accordance with the Greek Road Design Guidelines (OMOE-X, 2001) by utilizing the control design parameters for a design speed of 80km/h and a wide range of grade values, where the vertex point of the crest vertical curve is positioned at fixed points along the road axis. The investigation is based on a vehicle speed exceeding the design speed by 20km/h. In total 1874 cases of compound alignments were examined and the results revealed that the available sight distance is decreasing while grade increases. The vehicle speed on the tangent sections was proved unacceptable in terms of providing SSD adequacy. However, it was found that SSD adequacy is granted when the vertical vertex falls inside the circular arc of the curve’s horizontal alignment, while the optimum area is defined shortly before the horizontal vertex point.

5

Grade uncertainty and its impact on ore grade reconciliation between the resource model and the mine

Parhizkar A., Ataei M., Moarefvand P., Rasouli V.

Archives of Mining Sciences

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2011

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Vol. 56, no 1

119-134

EN

Major differences between estimated grade and actual grade are a usual problem in many open pit mines. The estimated grade is predicted in exploration stage from data obtained from boreholes, whereas the actual grade would be determined only after the mining operation. The poor reconciliation between the values of estimated and actual grades can cause major economic losses to the mining industry. Many different factors affect the reconciliation process in a mining operation. The nature of the orebody, the random uncertainty and the systematic errors are three main sources affecting the reconciliation process in exploration stage of the orebody. In this paper each source of uncertainty is studied and a probabilistic model is presented to determine the role of each item in total uncertainty of the grade parameter. The model ability was investigated in the study of real data taken from an iron open pit mine in Iran. The results showed the systematic uncertainty, the nature of the orebody and the random uncertainty are the main causes of poor reconciliation in the case study respectively.

PL

Poważne rozbieżności pomiędzy szacowaną a rzeczywistą jakością złóż rudy stanowią typowy problem w wielu kopalniach odkrywkowych. Szacowaną jakość określa się na etapie prac poszukiwawczych, na podstawie danych z otworów zaś rzeczywistą klasę złóż określić można jedynie w trakcie prac wydobywczych. Niewielka zgodność pomiędzy danymi szacunkowymi a rzeczywistymi powodować może znaczne straty finansowe dla sektora wydobywczego. Wiele rożnych czynników ma wpływ na poziom zgodności pomiędzy tymi danymi: charakter złoża rudy, niepewność losowa i błędy systemowe to trzy główne czynniki warunkujące poziom zgodności na etapie prac poszukiwawczych. W artykule tym zbadano te trzy główne źródła i zaproponowano model probabilistyczny dla określania roli poszczególnych czynników przyczyniających się do powstania niepewności odnośnie parametrów jakości złoża. Możliwości modelu przebadano na podstawie danych rzeczywistych uzyskanych z kopalni odkrywkowej rud żelaza w Iranie. Wyniki wskazują, że niepewność systemowa, charakter złoża i niepewność losowa w tej kolejności stanowią trzy główne czynniki warunkujące niewielki poziom zgodności pomiędzy danymi prognozowanymi a rzeczywistymi.