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Chilean mining is one of the main productive industries in the country. It plays a critical role in the development of Chile, so process planning is an essential task in achieving high performance. This task involves considering mineral resources and operating conditions to provide an optimal and realistic copper extraction and processing strategy. Performing planning modes of operation requires a significant effort in information generation, analysis, and design. Once the operating mode plans have been made, it is essential to select the most appropriate one. In this context, an intelligent system that supports the planning and decision-making of the operating mode has the potential to improve the copper industry’s performance. In this work, a knowledge-based decision support system for managing the operating mode of the copper heap leaching process is presented. The domain was modeled using an ontology. The interdependence between the variables was encapsulated using a set of operation rules defined by experts in the domain and the process dynamics was modeled utilizing an inference engine (adjusted with data of the mineral feeding and operation rules coded) used to predict (through phenomenological models) the possible consequences of variations in mineral feeding. The work shows an intelligent approach to integrate and process operational data in mining sites, being a novel way to contribute to the decision-making process in complex environments.
Manuel Saldaña; Purísima Neira; Víctor Flores; Pedro Robles; Carlos Moraga. A Decision Support System for Changes in Operation Modes of the Copper Heap Leaching Process. Metals 2021, 11, 1025 .
AMA StyleManuel Saldaña, Purísima Neira, Víctor Flores, Pedro Robles, Carlos Moraga. A Decision Support System for Changes in Operation Modes of the Copper Heap Leaching Process. Metals. 2021; 11 (7):1025.
Chicago/Turabian StyleManuel Saldaña; Purísima Neira; Víctor Flores; Pedro Robles; Carlos Moraga. 2021. "A Decision Support System for Changes in Operation Modes of the Copper Heap Leaching Process." Metals 11, no. 7: 1025.
Determining the uniaxial compressive strength of intact rock is the primary objective of a geomechanical project, and a reliable estimate in the early phases saves time and costs for more sophisticated laboratory tests. The problem is knowing which of the correlations between the resistance to uniaxial compression and point load index are reliable, those that cover one or several types of rock (depending on the type of statistical adjustment). In this work, they were evaluated with respect to limestone and travertine from experimental results, and the statistical models of the scale effect of the point load index were determined, and the uniaxial compressive strength being estimated from correlations reported in literature. The limestone model was ascending (strength increases as diameter increases), while the travertine model was descending (strength decreases as diameter increases), obtaining similar exponents for the scale effect equations modeled from the uniaxial compressive strength and point load index in both cases.
Solange Contreras; Manuel Saldaña; Norman Toro; Ignacio Pérez-Rey; Manuel González; Javier González. Scale Effect and Correlation between Uniaxial Compressive Strength and Point Load Index for Limestone and Travertine. Applied Sciences 2021, 11, 3672 .
AMA StyleSolange Contreras, Manuel Saldaña, Norman Toro, Ignacio Pérez-Rey, Manuel González, Javier González. Scale Effect and Correlation between Uniaxial Compressive Strength and Point Load Index for Limestone and Travertine. Applied Sciences. 2021; 11 (8):3672.
Chicago/Turabian StyleSolange Contreras; Manuel Saldaña; Norman Toro; Ignacio Pérez-Rey; Manuel González; Javier González. 2021. "Scale Effect and Correlation between Uniaxial Compressive Strength and Point Load Index for Limestone and Travertine." Applied Sciences 11, no. 8: 3672.
Stabilization of synthetic clay-rich tailings in seawater with sodium polyacrylate (NaPA) has been studied by measurements of yield stress, viscoelastic moduli, zeta potential, and particle chord length distribution. The tailings are kaolin-quartz and sodium montmorillonite-quartz mixtures in seawater at pH 8 at which all surfaces are anionic. The yield stress of both tailings decays exponentially with the dose of NaPA. Reducing the initial value of yield stress to a preset fraction (1-1/e) requires 52 g/ton NaPA for kaolin-quartz and 31 g/ton NaPA for montmorillonite-quartz tailing. At these dosages, in the linear viscoelastic range, both tailings respond similarly to the presence of NaPA, increasing their liquid-like character and suspension stability. The stabilizing action of NaPA is supported by a slight increase of the negative zeta potential and a clear shift of the particle size distribution to the finer sizes. The underlying stabilizing mechanism involves steric-electrostatic repulsion of the clay particles. These results suggest an alternative to improve the management of clay-rich tailings in processes that use raw seawater at natural pH.
Matías Jeldres; Pedro Robles; Pedro G. Toledo; Manuel Saldaña; Luciano Quezada; Ricardo I. Jeldres. Improved dispersion of clay-rich tailings in seawater using sodium polyacrylate. Colloids and Surfaces A: Physicochemical and Engineering Aspects 2020, 612, 126015 .
AMA StyleMatías Jeldres, Pedro Robles, Pedro G. Toledo, Manuel Saldaña, Luciano Quezada, Ricardo I. Jeldres. Improved dispersion of clay-rich tailings in seawater using sodium polyacrylate. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2020; 612 ():126015.
Chicago/Turabian StyleMatías Jeldres; Pedro Robles; Pedro G. Toledo; Manuel Saldaña; Luciano Quezada; Ricardo I. Jeldres. 2020. "Improved dispersion of clay-rich tailings in seawater using sodium polyacrylate." Colloids and Surfaces A: Physicochemical and Engineering Aspects 612, no. : 126015.
Crime analysis represents a great challenge to law enforcement considering that the sources to use for generating intelligence are diverse in content and/or structure. However, in recent years, techniques such as natural language processing, a field of computing, artificial intelligence and linguistics have been developed that allow to study the interactions between computers and human language, and that in turn can be used effectively in the analysis of large amounts of texts and in the subsequent derivation of interesting analytical results. This paper presents a model for analysis of criminal events from online newspapers, identifying the areas with the highest crime rates through the detection and geographical mapping of critical points and the analysis of the nature of the criminal event. The evaluation of the proposed model to estimate the perception of crime in the domain of the proposed communes indicates that it is efficient in categorizing the news and the nature of these (validated by the performance indicators).
Manuel Saldaña. An Empirical Study of the Perception of Criminality through Analysis of Newspapers Online. Journal of Information Systems Engineering and Management 2020, 5, em0126 .
AMA StyleManuel Saldaña. An Empirical Study of the Perception of Criminality through Analysis of Newspapers Online. Journal of Information Systems Engineering and Management. 2020; 5 (4):em0126.
Chicago/Turabian StyleManuel Saldaña. 2020. "An Empirical Study of the Perception of Criminality through Analysis of Newspapers Online." Journal of Information Systems Engineering and Management 5, no. 4: em0126.
In the rock mechanics and rock engineering field, the strength parameter considered to characterize the rock is the uniaxial compressive strength (UCS). It is usually determined in the laboratory through a few statistically representative numbers of specimens, with a recommended minimum of five. The UCS can also be estimated from rock index properties, such as the effective porosity, density, and P-wave velocity. In the case of a porous rock such as travertine, the random distribution of voids inside the test specimen (not detectable in the density-porosity test, but in the compressive strength test) causes large variations on the UCS value, which were found in the range of 62 MPa for this rock. This fact complicates a sufficiently accurate determination of experimental results, also affecting the estimations based on regression analyses. Aiming to solve this problem, statistical analysis, and machine learning models (artificial neural network) was developed to generate a reliable predictive model, through which the best results for a multiple regression model between uniaxial compressive strength (UCS), P-wave velocity and porosity were obtained.
Manuel Saldaña; Javier González; Ignacio Pérez-Rey; Matías Jeldres; Norman Toro. Applying Statistical Analysis and Machine Learning for Modeling the UCS from P-Wave Velocity, Density and Porosity on Dry Travertine. Applied Sciences 2020, 10, 4565 .
AMA StyleManuel Saldaña, Javier González, Ignacio Pérez-Rey, Matías Jeldres, Norman Toro. Applying Statistical Analysis and Machine Learning for Modeling the UCS from P-Wave Velocity, Density and Porosity on Dry Travertine. Applied Sciences. 2020; 10 (13):4565.
Chicago/Turabian StyleManuel Saldaña; Javier González; Ignacio Pérez-Rey; Matías Jeldres; Norman Toro. 2020. "Applying Statistical Analysis and Machine Learning for Modeling the UCS from P-Wave Velocity, Density and Porosity on Dry Travertine." Applied Sciences 10, no. 13: 4565.
Manuel Saldaña; Christian Escobar; Edelmira Galvez; David Torres; Norman Toro. Mapping of the Perception of Theft Crimes from Analysis of Newspaper Articles Online. 2020 15th Iberian Conference on Information Systems and Technologies (CISTI) 2020, 1 .
AMA StyleManuel Saldaña, Christian Escobar, Edelmira Galvez, David Torres, Norman Toro. Mapping of the Perception of Theft Crimes from Analysis of Newspaper Articles Online. 2020 15th Iberian Conference on Information Systems and Technologies (CISTI). 2020; ():1.
Chicago/Turabian StyleManuel Saldaña; Christian Escobar; Edelmira Galvez; David Torres; Norman Toro. 2020. "Mapping of the Perception of Theft Crimes from Analysis of Newspaper Articles Online." 2020 15th Iberian Conference on Information Systems and Technologies (CISTI) , no. : 1.
Black coppers are mineraloids with a high content of Cu and Mn. These have an amorphous crystalline structure that makes them refractory to conventional leaching processes. For this reason, these mineral resources are not incorporated in industrial leaching heap processes and are taken to dumps. In the present study, an agglomerate pretreatment process incorporating NaCl is evaluated, and a curing stage, followed by acid-reducing leaching for Cu and Mn dissolution from a high-grade black copper mineral. For this, an experimental design was developed both to evaluate the impact of the dependent variables on the response, to generate analytical models that represent the copper and manganese recoveries under the set of sampled conditions. The models indicate that the curing time and the NaCl concentration have a primary effect on the recovery of both elements. In contrast, the optimization model suggests that the optimal operating levels are reached at relatively high levels of time (>130 h) and of NaCl concentration (>22 kg/t).
Manuel Saldaña; Edelmira Gálvez; Ricardo I. Jeldres; Catalina Díaz; Pedro Robles; Manish Kumar Sinha; Norman Toro. Optimization of Cu and Mn Dissolution from Black Coppers by Means of an Agglomerate and Curing Pretreatment. Metals 2020, 10, 657 .
AMA StyleManuel Saldaña, Edelmira Gálvez, Ricardo I. Jeldres, Catalina Díaz, Pedro Robles, Manish Kumar Sinha, Norman Toro. Optimization of Cu and Mn Dissolution from Black Coppers by Means of an Agglomerate and Curing Pretreatment. Metals. 2020; 10 (5):657.
Chicago/Turabian StyleManuel Saldaña; Edelmira Gálvez; Ricardo I. Jeldres; Catalina Díaz; Pedro Robles; Manish Kumar Sinha; Norman Toro. 2020. "Optimization of Cu and Mn Dissolution from Black Coppers by Means of an Agglomerate and Curing Pretreatment." Metals 10, no. 5: 657.
The authors wish to make the following corrections to this paper
David Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316. Metals 2020, 10, 506 .
AMA StyleDavid Torres, Luís Ayala, Manuel Saldaña, Manuel Cánovas, Ricardo I. Jeldres, Steven Nieto, Jonathan Castillo, Pedro Robles, Norman Toro. Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316. Metals. 2020; 10 (4):506.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. 2020. "Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316." Metals 10, no. 4: 506.
Covellite is a secondary copper sulfide, and it is not abundant. There are few investigations on this mineral in spite of it being formed during the leaching of chalcocite or digenite; the other investigations on covellite are with the use of mineraloids, copper concentrates, and synthetic covellite. The present investigation applied the surface optimization methodology using a central composite face design to evaluate the effect of leaching time, chloride concentration, and sulfuric acid concentration on the level of copper extraction from covellite (84.3% of purity). Copper is dissolved from a sample of pure covellite without the application of temperature or pressure; the importance of its purity is that the behavior of the parameters is analyzed, isolating the impurities that affect leaching. The chloride came from NaCl, and it was effectuated in a size range from –150 to +106 μm. An ANOVA indicated that the leaching time and chloride concentration have the most significant influence, while the copper extraction was independent of sulfuric acid concentration. The experimental data were described by a highly representative quadratic model obtained by linear regression (R2 = 0.99).
Kevin Pérez; Norman Toro; Manuel Saldaña; Eleazar Salinas-Rodríguez; Pedro Robles; David Torres; Ricardo I. Jeldres. Statistical Study for Leaching of Covellite in a Chloride Media. Metals 2020, 10, 477 .
AMA StyleKevin Pérez, Norman Toro, Manuel Saldaña, Eleazar Salinas-Rodríguez, Pedro Robles, David Torres, Ricardo I. Jeldres. Statistical Study for Leaching of Covellite in a Chloride Media. Metals. 2020; 10 (4):477.
Chicago/Turabian StyleKevin Pérez; Norman Toro; Manuel Saldaña; Eleazar Salinas-Rodríguez; Pedro Robles; David Torres; Ricardo I. Jeldres. 2020. "Statistical Study for Leaching of Covellite in a Chloride Media." Metals 10, no. 4: 477.
The marine nodules are an attractive alternative source for the extraction of manganese due to the scarcity of high-grade metals on the surface. In the present investigation, working parameters (Fe2O3/MnO2 ratio and sulfuric acid concentration) were optimized for the dissolution of Mn from marine nodules using foundry slags. Finally, it is concluded that the optimum MnO2/Fe2O3 proportion is 1/2, while the optimum concentration of H2SO4 is 0.3 mol/L for a leaching time of 20 minutes achieving solutions of 70% Mn.
Kevin Pérez; Ángelo Villegas; Manuel Saldaña; Ricardo I. Jeldres; Javier González; Norman Toro. Initial investigation into the leaching of manganese from nodules at room temperature with the use of sulfuric acid and the addition of foundry slag—Part II. Separation Science and Technology 2020, 56, 389 -394.
AMA StyleKevin Pérez, Ángelo Villegas, Manuel Saldaña, Ricardo I. Jeldres, Javier González, Norman Toro. Initial investigation into the leaching of manganese from nodules at room temperature with the use of sulfuric acid and the addition of foundry slag—Part II. Separation Science and Technology. 2020; 56 (2):389-394.
Chicago/Turabian StyleKevin Pérez; Ángelo Villegas; Manuel Saldaña; Ricardo I. Jeldres; Javier González; Norman Toro. 2020. "Initial investigation into the leaching of manganese from nodules at room temperature with the use of sulfuric acid and the addition of foundry slag—Part II." Separation Science and Technology 56, no. 2: 389-394.
Multivariate models are a useful tool when studying the effects of independent variables on one or more dependent variables, since this approach allows modeling of the dynamics of complex systems based on simple analytical models with considerable certainty. Due to the decrease in the copper oxide mineral grades, leaching of copper sulfide minerals (secondary sulfides) has positioned itself as a benchmark of operation for the Chilean mining industry. The present work proposes the study of the effects of sulfuric acid, chloride concentration and time on the extraction of copper from sulfuric minerals (chalcocite), considering an experimental design, the surface optimization methodology and the adjustment of a quadratic model. The experimental data were adjusted by multiple regression analysis and were statistically analyzed. A model was developed to represent the copper extraction from the Cu2S mineral as a function of the statistically significant variables (chloride concentration and time) that contribute to explain the variation of the response variable under the set of parameters sampled.
Manuel Saldaña; Freddy Rodríguez; Anyelo Rojas; Kevin Pérez; Palma Angulo. Development of an empirical model for copper extraction from chalcocite in chloride media. Chemical Industry 2020, 74, 285 -292.
AMA StyleManuel Saldaña, Freddy Rodríguez, Anyelo Rojas, Kevin Pérez, Palma Angulo. Development of an empirical model for copper extraction from chalcocite in chloride media. Chemical Industry. 2020; 74 (5):285-292.
Chicago/Turabian StyleManuel Saldaña; Freddy Rodríguez; Anyelo Rojas; Kevin Pérez; Palma Angulo. 2020. "Development of an empirical model for copper extraction from chalcocite in chloride media." Chemical Industry 74, no. 5: 285-292.
Modeling of flotation processes is complex due to the large number of variables involved and the lack of knowledge on the impact of operational parameters on the response(s), and given this problem, machine learning algorithms emerge as an alternative interesting when modeling dynamic processes. In this work, different artificial neural network (ANN) architectures for modeling the mineral concentrate in a rougher-cleaner-scavenger (RCS) circuit based on the main process variables are generated (variables as the recovery of the rougher, cleaner and scavenger cells, along with disaggregated variables). Analysis of the global sensitivity was performed to study the importance of the individual and joint performances of the stages of the flotation circuit, reflected by sensitivity indicators that allow to infer the impact that the stages and operational parameters produce on the dependent variables (mineral concentrate in rougher, cleaner and scavenger cells, in addition to the global concentration in the RCS circuit). It should be noted that the ANN is a useful tool for modeling dynamic systems such as flotation, while sensitivity analysis shows that the operation of the three threads turns out to be crucial for the subsequent evaluation of the circuit, while the Unbundled variables that most interact with the overall recovery are gas flow rate, bubble and particle diameters, bubble velocity, particle density, and surface tension.
Manuel Saldaña; Luis Ayala; David Torres; Norman Toro. Global sensitivity analyses of a neural networks model for a flotation circuit. Chemical Industry 2020, 74, 247 -256.
AMA StyleManuel Saldaña, Luis Ayala, David Torres, Norman Toro. Global sensitivity analyses of a neural networks model for a flotation circuit. Chemical Industry. 2020; 74 (4):247-256.
Chicago/Turabian StyleManuel Saldaña; Luis Ayala; David Torres; Norman Toro. 2020. "Global sensitivity analyses of a neural networks model for a flotation circuit." Chemical Industry 74, no. 4: 247-256.
Norman Toro; Manuel Saldaña; Jonathan Castillo; Ricardo I Jeldres. MnO2 Dissolution from Marine Nodules with Tailings. Minerals: Technology and Advances 2020, 1 .
AMA StyleNorman Toro, Manuel Saldaña, Jonathan Castillo, Ricardo I Jeldres. MnO2 Dissolution from Marine Nodules with Tailings. Minerals: Technology and Advances. 2020; ():1.
Chicago/Turabian StyleNorman Toro; Manuel Saldaña; Jonathan Castillo; Ricardo I Jeldres. 2020. "MnO2 Dissolution from Marine Nodules with Tailings." Minerals: Technology and Advances , no. : 1.
Currently, there is a large amount of mineral resources not being exploited in large copper minings, a clear example are black copper minerals. These resources are generally not incorpo-rated into the extraction circuits or are not treated, either in stocks, leach pads, or debris. These exotic minerals have considerable amounts of Cu and Mn, which are commercially very attractive. They are refractory to conventional leaching processes, therefore, the use of reducing agents is necessary for treatment of these minerals in order to dissolve the present MnO2, which in turn allows Cu extraction. In this research, iron scrap Fe0 was used as a reducing agent for the dissolution of Mn from a black copper mineral in an acidic medium and compared to previous studies of the use of Fe2+ under the same conditions. In addition, the effects of a pretreatment process (agglomeration and curing) by adding NaCl are investigated in order to favor the reduction of MnO2. Finally, it was discovered that there is a higher kinetics of dissolution of Mn when working with Fe0 in short periods of time, although similar extraction efficiencies are obtained after prolonged times. The pretreatment process by adding NaCl resulted in increased Mn extraction in short periods of time (30 min). At applying high concentrations of the reducing agent, the effect of particle size on the dissolution rate of MnO2 was shown to be insignificant.
Norman Toro; Kevin Pérez; Manuel Saldaña; Eleazar Salinas-Rodríguez; Pía Hernández. Treatment of black copper with the use of iron scrap - part I. Chemical Industry 2020, 74, 237 -245.
AMA StyleNorman Toro, Kevin Pérez, Manuel Saldaña, Eleazar Salinas-Rodríguez, Pía Hernández. Treatment of black copper with the use of iron scrap - part I. Chemical Industry. 2020; 74 (4):237-245.
Chicago/Turabian StyleNorman Toro; Kevin Pérez; Manuel Saldaña; Eleazar Salinas-Rodríguez; Pía Hernández. 2020. "Treatment of black copper with the use of iron scrap - part I." Chemical Industry 74, no. 4: 237-245.
Mauricio Villanueva; Christian Calderón; Manuel Saldaña; Norman Toro. Modelling a SAG Grinding System through multiples regressions. METAL 2020 Conference Proeedings 2020, 1 .
AMA StyleMauricio Villanueva, Christian Calderón, Manuel Saldaña, Norman Toro. Modelling a SAG Grinding System through multiples regressions. METAL 2020 Conference Proeedings. 2020; ():1.
Chicago/Turabian StyleMauricio Villanueva; Christian Calderón; Manuel Saldaña; Norman Toro. 2020. "Modelling a SAG Grinding System through multiples regressions." METAL 2020 Conference Proeedings , no. : 1.
The deposits of Fe-Mn, in the seabed of the planet, are a good alternative source for the extraction of elements of interest. Among these are marine nodules, which have approximately 24% manganese and may be a solution to the shortage of high-grade ores on the surface. In this investigation, an ANOVA analysis was performed to evaluate the time independent variables and MnO2/reducing agent in the leaching of manganese nodules with the use of different Fe reducing agents (FeS2, Fe2+, Fe0 and Fe2O3). Tests were also carried out for the different reducing agents evaluating the MnO2/Fe ratio, in which the Fe0 (FeC) proved to be the best reducing agent for the dissolution of Mn from marine nodules, achieving solutions of 97% in 20 min. In addition, it was discovered that at low MnO2/Fe ratios the acid concentration in the system is not very relevant and the potential and pH were in ranges of −0.4–1.4 V and −2–0.1 favoring the dissolution of Mn from MnO2.
David Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316 .
AMA StyleDavid Torres, Luís Ayala, Manuel Saldaña, Manuel Cánovas, Ricardo I. Jeldres, Steven Nieto, Jonathan Castillo, Pedro Robles, Norman Toro. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals. 2019; 9 (12):1316.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. 2019. "Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents." Metals 9, no. 12: 1316.
Rock mechanics and rock engineering projects require determining, among other parameters, the uniaxial compressive strength (UCS) of rock. For such a purpose, it is not uncommon to perform ultrasonic pulse laboratory tests. Many researchers have found experimental relationships between strength and P-wave velocity, but these relationships are based mainly on dry conditions and without considering any other physical or chemical characteristics of the studied rock. Specifically, for limestone, there are 11 correlations reported in the literature, eight of which are simple and the remaining three are multiple, and, among the latter, only two of them consider the saturation. In order to evaluate the combined effect of P-wave velocity, density, and porosity on the UCS of saturated limestone, simple and multiple regression analyses were carried out on the test results of 13 saturated limestone specimens to determine the parameters of both previously mentioned predictive models. The results showed that density is not correlated with strength.
Javier González; Manuel Saldaña; Javier Arzúa. Analytical Model for Predicting the UCS from P-Wave Velocity, Density, and Porosity on Saturated Limestone. Applied Sciences 2019, 9, 5265 .
AMA StyleJavier González, Manuel Saldaña, Javier Arzúa. Analytical Model for Predicting the UCS from P-Wave Velocity, Density, and Porosity on Saturated Limestone. Applied Sciences. 2019; 9 (23):5265.
Chicago/Turabian StyleJavier González; Manuel Saldaña; Javier Arzúa. 2019. "Analytical Model for Predicting the UCS from P-Wave Velocity, Density, and Porosity on Saturated Limestone." Applied Sciences 9, no. 23: 5265.
Chalcopyrite is the most abundant copper ore and, consequently, the most utilised to produce metallic copper. The main route of treatment is through pyrometallurgical processes, but these emit significant quantities of SO2 into the atmosphere (e.g. 182,000 t/year among all Chilean smelters), producing mighty concern in the community. In this context, hydrometallurgy is presented as an alternative that may be more environmentally friendly; however, the difficulties of processing sulphide minerals prevent achieving sustainable efficiencies for the industry. In this research, a pure chalcopyrite mineral is leached at 25 °C with the addition of manganese nodules as an oxidizing agent, and wastewater with a high concentration of chloride that both enhances the dissolution and avoid the passivation of the chalcopyrite. The high concentrations of MnO2 (4/1 and 5/1) allows that the potential values can be between 580 and 650 mV, which favors the dissolution of CuFeS2. The XRD showed the formation of non-polluting species and, besides, they do not cause obstacles to the copper dissolution. High concentrations of chloride enable increasing copper solutions from CuFeS2, attaining favorable outcomes when working with wastewater instead of seawater.
Norman Toro; Kevin Pérez; Manuel Saldaña; Ricardo I. Jeldres; Matías Jeldres; Manuel Cánovas. Dissolution of pure chalcopyrite with manganese nodules and waste water. Journal of Materials Research and Technology 2019, 9, 798 -805.
AMA StyleNorman Toro, Kevin Pérez, Manuel Saldaña, Ricardo I. Jeldres, Matías Jeldres, Manuel Cánovas. Dissolution of pure chalcopyrite with manganese nodules and waste water. Journal of Materials Research and Technology. 2019; 9 (1):798-805.
Chicago/Turabian StyleNorman Toro; Kevin Pérez; Manuel Saldaña; Ricardo I. Jeldres; Matías Jeldres; Manuel Cánovas. 2019. "Dissolution of pure chalcopyrite with manganese nodules and waste water." Journal of Materials Research and Technology 9, no. 1: 798-805.
Multivariate analytical models are quite successful in explaining one or more response variables, based on one or more independent variables. However, they do not reflect the connections of conditional dependence between the variables that explain the model. Otherwise, due to their qualitative and quantitative nature, Bayesian networks allow us to easily visualize the probabilistic relationships between variables of interest, as well as make inferences as a prediction of specific evidence (partial or impartial), diagnosis and decision-making. The current work develops stochastic modeling of the leaching phase in piles by generating a Bayesian network that describes the ore recovery with independent variables, after analyzing the uncertainty of the response to the sensitization of the input variables. These models allow us to recognize the relations of dependence and causality between the sampled variables and can estimate the output against the lack of evidence. The network setting shows that the variables that have the most significant impact on recovery are the time, the heap height and the superficial velocity of the leaching flow, while the validation is given by the low measurements of the error statistics and the normality test of residuals. Finally, probabilistic networks are unique tools to determine and internalize the risk or uncertainty present in the input variables, due to their ability to generate estimates of recovery based upon partial knowledge of the operational variables.
Manuel Saldaña; Javier González; Ricardo I. Jeldres; Ángelo Villegas; Jonathan Castillo; Gonzalo Quezada; Norman Toro. A Stochastic Model Approach for Copper Heap Leaching through Bayesian Networks. Metals 2019, 9, 1198 .
AMA StyleManuel Saldaña, Javier González, Ricardo I. Jeldres, Ángelo Villegas, Jonathan Castillo, Gonzalo Quezada, Norman Toro. A Stochastic Model Approach for Copper Heap Leaching through Bayesian Networks. Metals. 2019; 9 (11):1198.
Chicago/Turabian StyleManuel Saldaña; Javier González; Ricardo I. Jeldres; Ángelo Villegas; Jonathan Castillo; Gonzalo Quezada; Norman Toro. 2019. "A Stochastic Model Approach for Copper Heap Leaching through Bayesian Networks." Metals 9, no. 11: 1198.
Multivariable analytical models provide a descriptive (albeit approximate) mathematical relationship between a set of independent variables and one or more dependent variables. The current work develops an analytical model that extends a design of experiments for the leaching of manganese from marine nodules, using sulfuric acid (H2SO4) in the presence of iron-containing tailings, which are both by-products of conventional copper extraction. The experiments are configured to address the effect of time, particle size, acid concentration, Fe2O3/MnO2 ratio, stirring speed and temperature, under typical industrial conditions. The recovery of manganese has been modeled using a first order differential equation that accurately fits experimental results, noting that Fe2O3/MnO2 and temperature are the most critical independent variables, while the particle size is the least influential (under typical conditions). This study obtains representative fitting parameters, that can be used to explore the incorporation of Mn recovery from marine nodules, as part of the extended value chain of copper sulfide processing.
Manuel Saldaña; Norman Toro; Jonathan Castillo; Pía Hernández; Emilio Trigueros; Alessandro Navarra; Toro. Development of an Analytical Model for the Extraction of Manganese from Marine Nodules. Metals 2019, 9, 903 .
AMA StyleManuel Saldaña, Norman Toro, Jonathan Castillo, Pía Hernández, Emilio Trigueros, Alessandro Navarra, Toro. Development of an Analytical Model for the Extraction of Manganese from Marine Nodules. Metals. 2019; 9 (8):903.
Chicago/Turabian StyleManuel Saldaña; Norman Toro; Jonathan Castillo; Pía Hernández; Emilio Trigueros; Alessandro Navarra; Toro. 2019. "Development of an Analytical Model for the Extraction of Manganese from Marine Nodules." Metals 9, no. 8: 903.