Juan M. Menendez-Aguado

• Doctor of Engineering
• Full Professor at University of Oviedo

Determining the Bond grindability test in a ball mill is one of the most commonly used methods in the mining industry for measuring the hardness of ores. The test is an essential part of the Bond work index methodology for designing and calculating the efficiency of mineral grinding circuits. The Bond ball mill grindability test has several restric...

This study evaluated two phytoremediation strategies at an active open-pit mining site within a dunite deposit, an ultramafic igneous rock rich in nickel. The strategies included phytostabilization for tailings, which are fine fractions resulting from rock processing, and phytoextraction for mining soil, composed of natural soil aggregates mixed wi...

Zinc processing tailings (ZPTs) of the Kharzet Youcef processing complex, Setif, Algeria, are mainly stockpiled in tailing dumps without use, occupying significant surfaces and negatively influencing the human environment and health. Incorporating ZPTs into building materials manufacturing is an effective solution to meet the dual objectives of env...

Here we describe two innovative approaches for remediating sediments contaminated with organotin compounds (OTCs, mainly TBT) and metal(loid)s. The first involves chemical stabilization through amendments with nanoscale zero-valent iron (nZVI), dunite mining waste, and coal tailings, materials that have not been previously studied for OTC remediati...

Mining is a crucial sector in the global economy, providing essential materials for various industries, including construction, electronics, and energy. However, traditional mining practices often have significant negative impacts on the environment. Therefore, integrating sustainable practices into mining has become vital. Grinding is a crucial st...

This paper summarises the evolution of the Water Poverty Index (WPI) application at different scales since its emergence. The review captures the main milestones and remarkable developments around the world. It sets the foundation for identifying the most appropriate version of the WPI, building on learning from previous versions. In addition, the...

According to the International Energy Agency, clean energy transitions significantly increase strategic minerals demand [...]

Metal(oid)es como el arsénico, cadmio, cobre, plomo y zinc, pueden suponer una amenaza medioambiental al presentarse en sedimentos marinos. Sin embargo, estos elementos también tienen valor económico, lo que ha generado un interés en su recuperación mediante el empleo de técnicas físico-químicas, aunque la separación magnética no ha sido empleada h...

In Ecuador, particularly in the El Oro province, gold mining has been historically hampered by arsenic contamination in the ores. This research addresses the persistent issue of arsenic in gold-bearing ores from Miraflores Mine in Cerro Azul, Atahualpa Canton, and the challenges it presents to mining operations. The study's purpose is to evaluate t...

Several metals and metalloids (e.g., As, Cd, Cu, Pb, Zn) are toxic at low concentrations, thus their presence in sediments can raise environmental concern. However, these elements can be of economic interest, and several techniques have been used for their recovery and some of them have been widely applied to mining or to industrial soils, but not...

We present the first application of electrostatic separation for soil washing. Soil samples were collected from the PTE-containing area of La Cruz in Linares, southern Spain. Using a single-phase high-tension roll separator with voltages ranging from 20 kV to 41.5 kV, we achieved yield values between 0.69% and 9%, with high recovery rates for certa...

Background and aim. The use of amendments to immobilize metals in polluted soils is a widely accepted remediation approach, and in the framework of the circular economy, amendments produced from mining and/or biomass waste have gained relevance. However, the application of such amendments can also mobilize metalloids. Here we propose the combinatio...

The aim of this research is the study of the WHIMS parameters on the improving process of a local (DD: Djebel Debbagh, East of Algeria) kaolin. The obtained results of performed XRF, SEM, and XRD characterization showed that this local material is an alumino-silicate containing kaolinite and halloysite with MnO and Fe2O3 impurities (respectively 39...

The removal of Cd2+, Zn2+ and Ni2+ from metal solutions onto waste toner power (WTP) was investigated. The influence of parameters such as pH, contact time, initial metal concentration and adsorbent dosage was studied in batch adsorption experiments. Batch equilibrium experiments showed that the highest removal efficiency for Zn2+ and Cd2+ occurs a...

The production and supply of raw materials in a global market are not without risks, and both the recent COVID-19 pandemic and the current one (Russia–Ukrania conflict) raised public awareness about the importance of multiple value chains [...]

A significant challenge in mineral raw materials comminution is the improvement of process energy efficiency. Conventional comminution techniques, although globally used, are far from being considered power-efficient. The use of high-voltage electric pulses in comminution is a concept that is worthy of study; despite its lack of industrial-scale va...

A population balance model is applied to a steel ball mill. Experimental data were obtained for two types of balls with different chemical compositions using a marked ball test in an industrial mill of a recognized cement producer company. The balls were marked since their manufacture by an international ball supplier who guided the entire experime...

There is no doubt about the practical interest of Fred Bond’s methodology in the field of comminution, not only in tumbling mills design and operation but also in mineral raw materials grindability characterization. Increasing energy efficiency in comminution operations globally is considered a significant challenge involving several Sustainable De...

Six different particle size distribution (Gates–Gaudin–Schuhmann (GGS), Rosin–Rammler (RR), Lognormal, Normal, Gamma, and Swebrec) models were compared under different metallurgical coke grinding conditions (ball size and grinding time). Adjusted R², Akaike information criterion (AIC), and the root mean of square error (RMSE) were employed as compa...

Over the years, alternative procedures to the Bond grindability test have been proposed aiming to avoid the need for the standard mill or to reduce and simplify the grinding procedure. Some of them use the standard mill, while others are based on a non-standard mill or computation techniques. Therefore, papers targeting to propose a better alternat...

As a continuation of a previous research work carried out to estimate the Bond work index (wi) by using a simulator based on the cumulative kinetic model (CKM), a deeper analysis was carried out to determine the link between the kinetic and energy parameters in the case of metalliferous and non-metallic ore samples. The results evidenced a relation...

It is a well-known fact that the value of the Bond work index (wi) for a given ore varies along with the grinding size. In this study, a variability bysis is carried out with the Bond standard grindability tests on different critical metal ores (W, Ta), ranging from coarse grinding (rod mills) to fine grinding (ball mills). The relationship between...

An evaluation of Relo grinding media (RGM, Reuleaux tetrahedron-shaped bodies) performance versus standard grinding media (balls) was made through a series of grinding tests, including a slight modification of the standard Bond test procedure. Standard Bond tests showed a reduction in the Bond ball mill work index (wi) of the mineral sample used in...

This paper presents the results of the characterization of alumina ball size distribution in the mill of a crushing and grinding plant. The mill was unloaded and the balls were sieved. Then, the results were adjusted to three kinds of models; two of them are the traditional models of Rosin-Rammler and Gates-Gaudin-Schumann. The third model applied...

Ta and Nb are considered critical raw materials due to their properties and potential applications in a wide range of sectors. This study deals with Sn-Ta-Nb minerals from the Penouta mine (Orense, Spain), the only active mine in Europe producing tantalum minerals. These minerals are obtained from mining waste accumulated during old mining operatio...

This study analyzes various regulatory framework mechanisms applied to prevent, minimize, and mitigate environmental accidents and disasters, within the extractive mining industry, in seven Latin American countries. The selected countries offer an ample view of the mining industry specter since each one of them is at the different development stage...

The European Commission (EC) maintains the consideration of tungsten as a critical raw material for the European industry, being the comminution stage of tungsten-bearing minerals an essential step in the tungsten concentration process. Comminution operations involve approximately 3–4% of worldwide energy consumption; therefore, grinding optimizati...

The optimization of processing plants is one of the main concerns in the mining industry, since the comminution stage, a fundamental operation, accounts for up to 70% of total energy consumption. The aim of this study was to determine the effects that ball size and mill speed exert on the milling kinetics over a wide range of particle sizes. This w...

The diamonds production has a great impact on the economy of the Republic of Angola, in which Catoca plant is of particular relevance. The autogenous grinding plays an important role in the technology of processing kimberlitic ores, as it has the purpose of achieving the release at the coarsest possible sizes. In order to evaluate the influence of...

Resumen La producción de diamantes tiene gran impacto en la economía de la República de Angola, en la que tiene especial relevancia la planta de Catoca, en la cual la molienda autógena juega un papel relevante en la tecnología del procesamiento de las menas kimberlíticas, pues tiene la finalidad de conseguir la liberación a tamaños lo más gruesos p...

In this work, we studied the soil washing of an As-polluted soil utilizing Wet High Intensity Magnetic Separation (WHIMS) after pre-treatment with nanoparticles. First, Fe-Ni nanoparticles of high saturation magnetization and appropriate size were synthesized. Soil samples were then pre-treated with a dose of nanoparticles before undergoing magneti...

Over the last decades, several reliable mathematical models have been developed for simulating ore comminution processes and determining the Work Index. Since Fred Chester Bond developed the Work Index standard procedure in 1961, numerous attempts have been made to find simpler, faster, and economically more advantageous alternative tests. In this...

The recent developments of steel and iron industries generated a huge consumption of iron ores which has attracted much attention for utilizing low-grade iron resources to satisfy this increasing demand. The present study focuses on the characterization and enrichment of the low-grade iron ores from Rouina deposit-Ain Defla-. Currently, the ore is...

The paper investigates the mineralogical composition of an iron ore issue of Rouina deposit -Ain Defla- Algeria and study the influence of washing on physic-chemical characteristics of samples

Hg and As mining-metallurgy plants have severely impacted environmental compartments. La Soterraña site (northern Spain) has been previously studied in this context. However, here we used a novel multi-purpose forensic approach to examine accumulations not only of mining-metallurgical waste (volumes above 80,000 t) but also C&D waste as a repositor...

The application of new learning methodologies in subjects related to engineering is required for students to develop their transversal skills, such as teamwork, creativity, problem-solving and the development of scientific thinking. On this account, Design Thinking was applied in the Mining Resources Prospecting module of the bachelor's degree in M...

The rheological behavior of mineral slurries shows the level of interaction or aggregation among particles, being a process control variable in processes such as slurry transportation, dehydration, and wet grinding systems. With the aim to analyze the effect of medium viscosity in wet grinding, a series of monosize grinding ball mill tests were per...

Mathematical models of particle size distribution (PSD) are necessary in the modelling and simulation of comminution circuits. In order to evaluate the application of the Swebrec PSD model (SWEF) in the grinding circuit at the Punta Gorda Ni-Co plant, a sampling campaign was carried out with variations in the operating parameters. Subsequently, the...

The circular economy seeks to minimize the use of raw materials and waste generation. In this context, here we addressed the use of dunite mining tailings and subproducts to stabilize metal(oid)s in polluted soils. We first characterized the dunite mining tailings and subproducts, and a paradigmatic polluted soil in depth to determine their chemica...

Mining activities in general, and quarrying processes in particular, generate huge amounts of tailings with a considerable presence of fine particles and with a variable composition of minerals, which could limit the direct application of those wastes. Under the paradigm of a circular economy, more effort has to be made to find adequate application...

The results of characterizing the alumina ball size distribution in two mills of a crushing and grinding plant are shown. The mills were unloaded and the ball charge was screened in order to establish the ball size distribution. For both mills, the balls retained during the unloading were compared to the balls retained at the beginning of the proce...

The area of Ponce Enríquez, Southern Ecuador, is one of the most important artisanal and small scale gold mining (ASGM) areas in the country, where informal mining operations can be found using amalgamation technique, even though it has been prohibited since 2010. Considering the potential impact of these mining operations, the present research foc...

Rouina is one of the oldest deposits exploited in Algeria and because the extracted materials contains high levels of silica and alumina it’s considered low-grade iron ore which make it intended for cement factories in central and western Algeria, where it is used as an adjuvant. These characteristics of Rouina iron ore raise the challenge for mine...

Soil washing is a remediation technology based on the adaptation of techniques habitually used in mineral processing to recover contaminants from polluted soils. Its main scope is the reduction of the total volume of contaminated soil, which could later be treated by biological, chemical, or thermal procedures. Since the contaminants are usually as...

The present study focuses on soil washing enhancement via soil pretreatment with nanoscale zero-valent iron (nZVI) for the remediation of potentially toxic elements. To this end, soil polluted with As, Cu, Hg, Pb and Sb was partitioned into various grain sizes (500-2000, 125-500 and <125 μm). The fractions were pretreated with nZVI and subsequently...

Crushing mathematical modeling using particles population balance method is a fundamental tool for process analysis, optimization and design. This paper deals with the evaluation of the fracture events and process in cone and rolls crushers. For that proposes, is taken as reference Whiten (1972) structural model modifying fragmentation distribution...

Abstract Crushing mathematical modeling using particles population balance method is a fundamental tool for process analysis, optimization and design. This paper deals with the evaluation of the fracture events and process in cone and rolls crushers. For that proposes, is taken as reference Whiten (1972) structural model modifying fragmentation dis...

Ball mills have a low efficiency rate partially due to the lack of a proper method to monitor the mill filling level, which makes it difficult to control the grinding process. The purpose of this paper is to explore the possibilities that DEM offers to characterize the load torque of tumbling ball mills in the frequency domain and, from this charac...

La modelación matemática con ayuda de los métodos de balance de población de partículas resulta imprescindible cuando se trata de la evaluación de los procesos y eventos de fracturas que tienen lugar en la trituración por impacto. Con el propósito de valorar la influencia de la energía de fragmentación y la razón de alimentación a la trituradora en...

A rheological modifier was used to prepare solutions with viscosities of 1, 4, 6 and 8 cp, which exhibited Newtonian behavior. These solutions were later used to prepare suspensions of monosize quartz (53, 45 and 38 microns) at 60 % in solids. Monosize grinding tests in a laboratory ball mill were performed to determine breakage parameters, with di...

Bond standard procedures are often used in design of comminution circuits, especially in the case of ball mill grinding circuits. Although it is usually considered as an industry standard, its procedure was not fully defined by Fred Bond, and sometimes sensible variations in test results can be obtained due to some undefined steps in the method. Th...

This paper describes a feasibility study of physical soil washing techniques to separate potentially toxic elements, such as As, Cu, Hg, Pb and Sb, in a brownfield affected by pyrite ash disposal. To this end, complete pedological and geochemical analyses were conducted in order to determine the properties of the soil. Afterwards exhaustive lab-sca...

As a result of the artisanal mining activities in Ecuador (specially in Ponce Enriquez mining area, province of Azuay), great quantities of mining wastes have been disposed, usually without adequate management standards. Consequent acid rock drainage has been responsible of surface and underground water and surface water bodies. The aim of this stu...

As a result of the artisanal mining activities in Ecuador (specially in Ponce Enriquez mining area, province of Azuay), great quantities of mining wastes have been disposed, usually without adequate management standards. Consequent acid rock drainage has been responsible of surface and underground water and surface water bodies. The aim of this stu...

Bond standard procedures are often used in design of comminution circuits, especially in the case of ball mill grinding circuits. Although it is usually considered as an industry standard, its procedure was not fully defined by Fred Bond, and sometimes sensible variations in test results can be obtained due to some undefined steps in the method. Th...

The present work deals with the impact crusher energy efficiency at San Andres Zeolitic Plant. Varying the operational parameters levels (rotor velocity, hammer row number and crusher capacity) were carried up two experimental series: First series was aimed to obtain the influence of the operational parameters on the power consumed by the crusher m...

The abandonment of Hg-As mining and metallurgy sites, together with long-term weathering, can dramatically degrade the environment. In this work it is exemplified the complex legacy of contamination that afflicts Hg-As brownfields through the detailed study of a paradigmatic site. Firstly, an in-depth study of the former industrial process was perf...

Purpose The development of mathematical models to accurately represent the particle size distribution (PSD) of sediment has been addressed by different authors. Here, we introduce the three-parameter Swrebec function as a tool to fit the PSD of sediments. Moreover, we also assess the physical meaning of the undulation parameter (b) in the function....

This article presents the results of applying a media selection methodology based on a population balance model to a ceramic ball mill; the experimental data were obtained through the marked ball test in a white-cement grinding pilot plant. Three types of balls from different suppliers (I,II and III) were used in order to study the wear occurring i...

Monosize quartz sand suspensions (53, 45 and 38 microns) were prepared in water at 60% solids weight and were ground for a fixed period of 10 min, in a lab ball mill (16cm diam x18 cm long), with steel balls of 4, 3, 2 cm in diameter. Resulting size distributions were fitted to the Swrebec function. This function was initially proposed to fit coars...

Ball mills can be frequently found in ore grinding facilities. These machines show high energy consumption together with a low efficiency. As a consequence, even a small improvement on the performance of the grinding process can have a huge impact in the operating costs of the plant and in the optimization of energy resources. One of the reasons fo...

The aim of this study was the optimization of the power consumption in a grinding plant of silica and the consequent reduction of CO2 emissions. The methodology used consisted on applying the Bond theory for the selection of raw materials to the plant, which operates at two different grinding sizes (100% passing 50 and 75 μm). The experimental tes...

The industrial history in the district of Linares (Spain) has had a severe impact on soil quality. Here we examined soil contaminated by lead and other heavy metals in "La Cruz" site, a brownfield affected by metallurgical residues. Initially, the presence of contaminants mainly associated with the presence of lead slag fragments mixed with the soi...

The ensuing lines correspond to the algorithm of attributive analysis which are used in the software COS. This software can be used for the optimization of concentration experiments in both mineral processing and soil washing studies.

Para el tratamiento del drenaje ácido de Mina Grande del Cobre ubicada en la provincia cubana de Santiago de Cuba, se realiza un estudio en columnas de flotación con la utilización del amilxantato de potasio como reactivo colector. La investigación se lleva a cabo con el objetivo de demostrar la aplicabilidad de esta técnica en la descontaminación...

Soils in abandoned mining sites generally present high concentrations of trace elements, such as As and Hg. Here we assessed the feasibility of washing procedures to physically separate these toxic elements from soils affected by a considerable amount of mining and metallurgical waste ("La Soterraña", Asturias, NW Spain). After exhaustive soil samp...

The subject of this paper is particle population balance models (PBM) that describe mineral impact crushing behavior; it is mainly concerned with the selection and fragmentation distribution function due to their importance in this context. The data obtained by Datta (1999) by applying impact pendulum testing to single limestone particles, used by...

A study was carried out to analyse the behaviour of internal flows in a closed grinding circuit. The study was performed through mathematical modelling, using the Cumulative Based Kinetic model and obtaining the necessary parameters at laboratory scale with various minerals. Particle size variations in all flows of the circuit were analysed with the...

Se modeló la trituración por impacto del mineral de zeolita del yacimiento San Andrés, Holguín, utilizando los modelos de Nikolov, basados en los métodos de balance de la población de partículas. Para ello se determinó el comportamiento de la función de clasificación y la de distribución de la fragmentación de este mineral utilizando una instalació...

A partir de establecer las características y parámetros físicos y fisicomecánicos de las tobas zeolitizadas del yacimiento Caimanes se elaboró una propuesta de variante tecnológica para la preparación mecánica. La composición granulométrica de los productos triturados se determinó mediante el análisis de tamizado por vía seco-húmeda. El índice de B...

Soil in a brownfield contaminated by pyrite ashes showed remarkably high concentrations of several toxic elements (Hg, Pb, Zn, Cu, Cd, and As). Initially, we assessed various physical, chemical and mineralogical properties of this soil. The data obtained, and particularly multivariate statistics of geochemical results, were useful to establish the...

Laboratory scale leaching tests were carried out in different experimental conditions, with monitoring of gold and silver recovery, the concentration of cyanide used in leaching, solution pH, and precious metal adsorption onto clay. Evidence for the adsorption or re-precipitation of gold from cyanide solutions onto clay minerals is conclusive and i...

The purpose of this paper is to outline the findings of the evaluation of the grinding process of limonite and serpentine minerals present in oxidized Ni–Co ores, which are contained in the lateritic soils of the north-eastern region of Cuba. The grindability study supporting this paper was based on the execution of various tests aiming to determin...

This investigation produced a model for impact crushing of a zeolite ore body in San Andrés, Holguín, by using Nikolov's models, which are based on particle population balance. To complete this, the performance of classification and ore fragmentation distribution variables were identified though a lab trial facility. The experimental results allowe...

In the current work the mineralogical composition of zeolitic tuffs of Caimanes deposit, in Moa region is characterized, with the pourpuse of its benefit. The characterization of the initial sample was carried out to determine the qualitative mineralogical composition and also to quantify the present phases, to establish the texture, the degree of...

Characterization based on physical and physico-mechanicalparameters of zeolitic tuffs from Caimanes deposit was done in order to obtain technological variants for its mechanical treatment. Granulometric composition of products of mechanical treatment was made by sieve analysis through the wet-dry way. Bond index, grinding kinetic and the selection...

This paper presents an analysis of the potential benefits of implementing energy sustainability concepts during comminution processes. The work is based on the classical comminution theory and on the theoretical postulates of the multi-component grinding. The assessment of the Punta Gorda grinding plant is presented as a case study. It applies fact...

In the present paper, some calculation methodologies applied to the simulation of Bond test in grinding processes were presented. A comparative analysis was made with simulation results, using various methodologies, of the ball mill Bond test based on real values of the work index. This analysis was carried out with various minerals in a wide range...

In this paper, the current profile of the environmental engineer and the programming of the subject “Environmental Engineering and Technology” corresponding to the studies of Mining Engineering at the University of Oviedo in Spain, is discussed. Professional profile, student knowledge prior to and following instruction as well as available teaching...

The Bond work index is one of the most useful and interesting parameters used in designing grinding equipment. However, it must be obtained under restrained conditions, especially in regards to the Bond standard lab mill. The main objective of this study is to show how this index can be obtained using a Denver ball mill, which is present in most mi...

The Bond work index is one of the most useful and interesting parameters used in designing grinding equipment. However, it must be obtained under restrained conditions, especially in regards to the Bond standard lab mill. The main objective of this study is to show how this index can be obtained using a Denver ball mill, which is present in most mi...

RESUMEN El presente trabajo tiene como objetivo la caracterización de las zeolitas de Caimanes para la propuesta de variante tecnológica de la preparación mecánica. La composición granulométrica de los productos fue determinada mediante el análisis de tamizado por vía seco-húmedo. El índice de Bond, la cinética de molienda y la función selección fu...

El presente trabajo tiene por objeto realizar la selección de los reactivos floculantes y coagulantes más adecuados para disminuir el contenido de sólidos de un efluente proveniente de las balsas de sedimentación de una planta de beneficio de mineral fluorita, que vierte a un cauce público, con un contenido de sólidos del 1 %. La alimentación a las...

The objective of this work is to carry out a selection study of the most adequate flocculation-coagulation reagents to reduce the solids content in the overflow from the settling lagoons of a fluorspar processing plant. This overflow has 1% solids content, clarified from a feed of 25% solids in the settling lagoons, and is pilled into a river. The...