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The effect of water quality change on copper flotation

Acuña Claudio, Aedo Camila, Leiva Claudio, Flores Víctor

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 186190

EN

Given the significant consumption and future demand for water resources, this paper intends to find the conditions for using a flotation process with different water quality. One of the alternatives is using water under secondary treatment with industrial water mixtures to partly recycle domestic wastewater and maximize metallurgical benefits. Results show that using wastewater (only with secondary treatment) in flotation is detrimental to copper recovery. However, molybdenum recovery is significantly improved. For mixtures with 50 [%] wastewater, 50 [ppm] frother, 20 [ppm] collector, and pH 10, copper recovery decrease amounts to 0.4 [%], while molybdenum shows a 2.4 [%] recovery increase. In addition, copper concentrate grade decreases by 1.4 [%], while molybdenum grade remains. Therefore, using wastewater is viable, particularly in the case of molybdenum. So, this study proposes using of water mixtures in the copper depression stage to improve molybdenum recovery.

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Flotation kinetic tracking of sand contaminated with hydrocarbons : image analysis of pulp color changes in time

Acuña Claudio, Humire José, Leiva Claudio

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 176307

EN

Hydrocarbon contamination in the environment poses a significant challenge, and various control methods have been explored. Soil remediation by flotation has been proposed as an effective approach. This method involves the separation of hydrophobic compounds, such as soil hydrocarbons, by introducing air into a stirred reactor containing the soil pulp designated for remediation. Experiments were conducted using a 5 L Batch flotation cell to evaluate operating conditions. These experiments focused on obtaining flotation kinetics with different organic mixtures, including fine sands measuring under 150 μm. The experimental design encompassed airflow, hydrocarbon concentration, and surfactant dosage. The research utilized a diluted pulp (3% solids) with a high organic concentration (8 and 17 g/L). Flotation kinetics were measured by developing an innovative technique based on pulp color and image processing software. This technique facilitated the tracking of concentration changes over time under Beer-Lambert's Law. Subsequently, the results were adjusted using kinetic models commonly employed in mineral flotation, including the first-order, Kelsall, and Klimpel models. This comprehensive analysis sought to elucidate the underlying phenomenology and assess the potential for industrial-scale implementation. The laboratory findings indicate the possibility of achieving recoveries of up to 87%, with a first-order kinetic constant of 0.7 (1/min). Both the gas flow rate and the addition of surfactant exert substantial influence on this constant, consistent with the observed phenomenology of this study. This study explores the integration of image analysis in flotation for hydrocarbon-contaminated soil remediation. The research aims to optimize remediation strategies by examining variables such as Beer-Lambert's law and prevalent kinetic models. The study focuses on scalable, eco-friendly decontamination methods, emphasizing enhanced process control and comprehension within soil flotation systems.

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Enhancing bubble bize prediction in flotation processes : a drift flux model accounting for frother type

Leiva Claudio, Acuña Claudio, Luukkanen Saija, Cruz Constanza

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 178234

EN

This communication presents a methodology, based on a modified drift flux model, to determine bubble size distribution in column flotation. The modified drift flux model incorporates a surfactant-type parameter. This parameter considers the impact of surfactant on bubble hydrodynamics. The methodology aims to improve the accuracy of bubble size distribution prediction, which presents deviation depending on surfactant type (i.e. polyglycolic based or alcoholic base). Many authors have proposed different mathematical improvements to reduce de experimental data deviations in the presence of different surfactants. However, from 1988 to 2022, the determination coefficient, or the quality of the adjustments, from the proposed mathematical models is, at the most, 92% (relative error). The proposed methodology improves the quality of the adjustments to 98.6, adding a single parameter for groups of surfactants. This methodology incorporates a single parameter in the terminal velocity calculation that can compensate for the impact of surfactant type in bubble hydrodynamic (bubble skin friction or drag coefficient, bubble wake, bubble shape, bubble rigidity). This parameter is a function of the gas holdup calculated from gas velocity measured and the bubble size distribution calculated (deviated) from gas holdup and gas velocity measured. The methodology is validated with reported experimental results and proposed modifications from various authors. The confidence interval (2 σ) is reduced from 0.11mm to 0.05mm in the case of (Yianatos, Banisi, Ostadrahimi). In the case of the recently reported experimental results from Maldonado and Gomez, the confidence interval is reduced from 0.31 mm to 0.09 mm. These results improve bubble size estimation based on drift flux in column flotation, contributing to a better understanding of surfactant impact on bubble swarm hydrodynamics.