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This article deals with the productivity of the economy of Paraná, seeking its measurement, evaluation of its sector profile and verification of the status of innovation activity. The modality under analysis is the labor productivity, to which the shift and share method is applied as a way to decompose its growth over the last two decades, in the structural and intra-sectoral components. The results indicate the increase in productivity given mainly by agriculture, along side the stagnation in the industry and the reduced expansion in the service sector. Specifically for the extractive and processing industries, the exercises also show general levels of stagnant productivity. In these industries, the low growth in shift and share analysis results mainly from intra-sectoral gains, concentrated in some branches of activity. In final section, the work points out expressive spaces of expansion of the innovation process across the Paraná production. [ABSTRACT FROM AUTHOR]

Starches are depressant reagents used in mineral flotation in order to confer selectivity to the process. For this, they need to be previously gelatinized, with the alkaline method being the most used technique in the mineral industry. In Brazil, NaOH is used as alkali and the flour/NaOH ratio is a parameter analyzed in this process. Although they are important, studies on this topic are scarce in the literature. That said, the work consisted in determining the ideal flour/ NaOH ratio for the gelatinization of depressants based on corn, sorghum and millet and in proving the effectiveness of the process under optical microscopy with polarized light. Subsequently, flotation tests with niobium ore using corn, millet and sorghum flours and their respective mixtures as depressants were carried out and the results were compared with industrial corn starch. The results showed that the new proposed depressants used smaller amounts of NaOH to be gelatinized in relation to corn starch. The optical microscopy stage confirmed the disruption of Maltese crosses for all flours, indicating complete gelatinization. The best pyrochlore depressant was sorghum flour and the results showed statistical similarity with corn starch. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) technology has been receiving a lot of attention since the 1990s because it has been chosen as an option for mitigating climate change. The legal and regulatory frameworks necessary for the broad development of this technology are considered incipient in most countries, as in Brazil. This study showed that Brazil doesn't have specific laws for the regulation of CCS. It can be concluded that Brazil can build on existing regulation in the mining and oil industry to develop a specific regulation on CCS. It was possible to observe, based on the existing regulations in the U.K., the E.U., Denmark, Australia, the USA, and Canada, that for regulation to be effective, consideration of factors such as clarity and efficiency of the administrative process of applying for and obtaining approval for CCS projects and long-term liability for closure, monitoring, and accidental releases of CO2 is essential. [ABSTRACT FROM AUTHOR]

Over the past decade, the extraction of ores in Brazil has increased vertiginously, driven by the neodevelopmental program of the governments of the Workers' Party. In order to get a better view of the facts, state investments in the sector, from 2011 to 2016, were over US $ 66 billion. In 2014, only the state of Minas Gerais, which historically constitutes the country's most important mineral production center, produced a mineral balance of US $ 14 billion. This scenario, however, has been responsible for a set of contradictions to great extent, as it has been demonstrated in the case of Paracatu, a municipality of Minas Gerais. Our research sought to identify the social and environmental impacts that have been provoked by the mining industry in this municipality. In methodological terms, we set up the politicaleconomic conditions under which the mining activity gained centrality in Brazil. Then, based on the available literature, we identified some contradictions on the expansion of this economic activity in the municipality of Paracatu, manifested in the form of socioenvironmental conflicts. Finally, we presented the public health situation, based on the report given to us by a distinguished local scientist in the area. [ABSTRACT FROM AUTHOR]

The mineral industry generates large amounts of tailings, and because of many accidents that have occurred with conventional dams, studies focus on tailings dewatering before their disposal. This study evaluates the properties of the red mud to determine their rheological behavior and stability for disposal in dams. For this, the red mud was flocculated with commercial cationic polymer and thickened. The thickened tailing was submitted to rheological tests with the vane rotor and slump test, in order to obtain information about yield stress and slump height of the tailings. The results show a strong influence of the initial solids concentration in particle aggregation, which could be noticed by the increase in particle cohesion and yield stress of thickened tailings; besides reduction of the slump height with the increase of initial solids concentration. It was possible to produce thickened tailings, reaching τ0 = 160 Pa, very close to the value specified for mineral paste, besides up to 90% water recover. [ABSTRACT FROM AUTHOR]

Studies involving tailings have raised mineral industry awareness because of its potential to increases in production as well as a reduction of the environmental liabilities. The main material of this study is an iron ore tailing from the Mineração Usiminas-MG-Brazil dam, collected through probe holes and characterized by size, chemical e mineralogical analyses. Flotation assays were also carried out, evaluating the ground corn (Flotamil75 and Flokit415) and cassava flour (FF01 and FF73) depressant action, aiming at achieving a concentrate adequate for use in the metallurgical industry. The size distribution of the tailing indicated 25% passing 10 μm and 15% above 297 μm, which was adjusted by classification and desliming. The Fe and SiO2 contents were 44.3% and 30.9%, respectively. The main mineral identified were hematite and quartz, and to a lesser extent, ferruginous earthy aggregates. In the analysis of the depressants, the cassava flour presented higher water absorption index and lower pH, compared to ground corn. The cassava flour FF73 reached the best performance in the flotation: metallurgical recovery 75.88% and 2.24% sio2 in concentrate. [ABSTRACT FROM AUTHOR]

This paper analyses the territory of the southeastern mesoregion of the Pará State, as one of the preferential locus of conflicts that involves different social actors and the mining companies, besides contesting analytically the form of the economic and social development adopted by the Brazilian government in the Amazon of the Pará State at the dawn of the 21st century. The southeastern mesoregion of the Pará State is the most affected by the mining activities of the principal mineral company of the State, the Valle Company. These social and territorial impacts have brought into debate if the mining is the only way of regional development. The conflicts of interests among the populations directly affected and the mineral policy in the Amazon region, have raised a broad debate in the affected societies in the last 30 years of the mineral exploration in the region, confronting the richness and poverty as a remarkable regional landscape, and proposing to reflect about the effects of the mining activities in the mining towns of the Pará State. [ABSTRACT FROM AUTHOR]

The article offers mining news briefs of Brazil. Mining engineer Francisco Sette Bicalho died on April 14, 2015 in Belo Horizonte, Brazil. The Brazilian Navy received the hydrographic research vessel "Vital de Oliveire" on July 23, 2015 to be used for water prospecting of mineral resources. The Instituto Brasileiro de Mineração (IBRAM) will be holding the 16th Brazilian Mining Congress and the International Mining Exhibition from September 14-17, 2015 in Belo Horizonte.

This study aim to analyze the structure of a Local Productive Arrangement (LPA) in the mining sector in one Brazilian Microregion, through the description of their origin, the mapping of productive agents and institutions involved, the explanation of its structure, based on variables related to external economies and internal economies, and identify their stage of evolution. This is a qualitative, descriptive, exploratory and documentary, in the form of case study, which used as a tool for data collection a semi structured interview guide used with the managers of the mining cooperatives. Data were analyzed using the technique of content analysis, under a closed procedure, and document analysis. The main result of the research is that the LPA is in transition from the embryonic stage to growth, once, according to the model adopted in the study, their structure has characteristics of both stages. The study demonstrates to be relevant for treating strategic improvements in the way we manage our business, proposed by forming partnerships between organizations or interorganizational relations of productive cooperation, with an objective to obtain competitive advantages. [ABSTRACT FROM AUTHOR]

The traditional method for the disposal of slurry in tailing dams requires large areas, with large environmental impact and therefore makes it difficult to acquire new licenses. The proximity of urban areas, together with public pressure, has raised the need to seek alternatives for this methodology. A viable solution to this issue will contribute to the environmental licensing process for new projects, ensuring the survival of mining in the Iron Quadrangle. Laboratory-scale filtration tests were conducted with tailing's samples using the main filtering technologies: vacuum filtration, pressure, hyperbaric and capillary filters. The results showed that with the exception of the slimes, it is possible to filter the tailings from the processing plants with a good filtration rate and residual moisture suitable for stacking. The filtration of slimes under pressure resulted in low filtration rate and high residual cake moisture (around 20%). The resulting cake could be mixed with the coarse tailings and / or mine waste to facilitate its stacking, although it requires further geotechnical studies. [ABSTRACT FROM AUTHOR]

Hydrocyclones are devices worldwide used in mineral processing for desliming, classification, selective classification, thickening and pre-concentration. A hydrocyclone is composed by one cylindrical and one conical section joint together, without any moving parts and it is capable of perform granular material separation in pulp. The mineral particles separation mechanism acting in a hydrocyclone is complex and its mathematical modelling is usually empirical. The most used model for hydrocyclone corrected cut size is proposed by Plitt. Over the years many revisions and corrections to Plitt's model were proposed. The present paper shows a modification in the Plitt's model constant, obtained by exponential regression of simulated data for three different hydrocyclones geometry: Rietema, Bradley and Krebs. To validate the proposed model literature data obtained from phosphate ore using fifteen different hydrocyclones geometry are used. The proposed model shows a correlation equals to 88.2% between experimental and calculated corrected cut size, while the correlation obtained using Plitt's model is 11.5%. [ABSTRACT FROM AUTHOR]

The article discusses various aspects of promotion of mining industries in Ouro Preto, Brazil which provides several opportunities to generate revenue. It highlights that the collected revenues can help in providing quality services to the public. It also analyzes dependency of residents in Ouro Preto, Brazil for their financial income that comes through the mining industries.

This study presents the results obtained using geostatistical simulation techniques combined with pit optimization and sequencing to assess the grade uncertainty impact in mine planning and reserve assessment. Traditional approaches use an estimated model by geostatistical methods (Ordinary Kriging, Indicator Kriging) or even classical methods of estimation (IPD, polygons, moving average). In the same manner, to evaluate mining projects, analyses considering economical sensitivity aspects were made, disregarding the uncertainty of the geological model. This study demonstrates that grade estimation can have a relevant impact on the uncertainty over mining projects, even in the open pit design, i.e. in the feasibility study. [ABSTRACT FROM AUTHOR]

This paper discusses the results of a mixed grinding simulator application based on an artificial neural network (multiple-layer perceptron using a back-propagation-like algorithm with moment). The data used came from a previous paper entitled "Selective grinding of dolomite and quartz mixes". The Shewhart control chart for individual values was used in order to verify the statistical stability of the simulation process results, which was useful for testing acceptance. The results have displayed good performance of this tool related to mix grinding simulation, a common issue in the mining and metallurgical sectors. [ABSTRACT FROM AUTHOR]

Logistics has become a decisive process for the survival of companies. Logistic aspects are responsible for the flow of materials and information from the supplier to the consumer, and have a direct impact on the performance of companies, as well as on the costs of the products and services they offer. This is enough to justify the addition of logistic aspects as tools for analysis and material selection. This work aims at presenting the development of a model for the selection of metallic material, which considers the logistic aspects on the decision process. For this reason, we have used an adaptation of the PERT net (Program Evaluation and Review Technique), relating indicators of variables from material selection with those from logistics. For the purpose of validation, we then implemented the model and presented it to experts of the mining-metallurgical sector. These experts had previously reported a lack of management systems that support the selection process relating to material and logis-tic information. As a result, they considered the proposed model to be an important instrument for undertaking managerial decisions. [ABSTRACT FROM AUTHOR]

Women are gaining space in the public sphere, in relation to the labor market and social representations. In this context, the mineral extraction sector stands out, as it has been accepting women in all its functional extensions. Given this, we intend to analyze the process of gender relations in the organizational context of a mining company. Discussions that guide the study of gender relations and subjectivity in work are used as reference. Research methodology is based on social phenomenology as conceived by Alfred Schütz. We conclude that women have managed gains in the mining industry, but these achievements are due to masculinization, as in fact there is no respect and appreciation for their differences. The legitimacy of women's work occurs only according to existing standards of male performance. Thus, this work is relevant in its contribution to scientific research on gender, and to study the relationships between men and women in an environment with such unique characteristics as the mining industry. In addition, the work features a unique use of phenomenology in social research on gender and might serve as a reference for future investigations. [ABSTRACT FROM AUTHOR]

Underground mine planning is an important element for achieving project re-alization in the current highly competitive scenario. This is due to the peculiarities of the underground mines, where it is difficult to obtain profound knowledge about the body and location of the underground excavations. Computer applicationsspatially visualize the ore body with its geological sec-tions and mineral formation contours. This visual is in 3D that facilitates the alloca-tion of major mine development services. Although such resources are available, their mining applications are generally developed for open pit mining methods, and is still incipient for underground mine-development methodologies. With the use of applications for mine development and planning, and the simi-larity of existing mines, it was possible to prepare the infrastructure project for a specific underground mine, and a 3D view of its underground openings. It was also possible to develop a methodology for drawing the galleries described. This paper deals with the selection of mining methods for a major simulated mineral deposit and describes breakthroughs of underground mine development de-sign using a commercial mining application. [ABSTRACT FROM AUTHOR]

In underground mining, daily a fleet of LHDs must be allocated to a haulage network of drifts for extracting ore according to a plan-driven strategy. This plan is hierarchically decided by a higher management level and it contains the number of ore bucketfuls to be extracted from each drawpoint within a drift for each working shift. In this paper, an integer programming (IP) model for minimizing the makespan of drift workload is formulated and a polynomial time optimal algorithm for its resolution is proposed. Next, a set of decision rules obtained from the algorithm above is integrated into the decision-making process (DMP). This DMP is simple to execute for LHD operators, determines the optimal makespan, and whether or not it can be carried out in the working shift. Finally, a comparative analysis between the DMP proposed and the DMP used in El Teniente copper underground Chilean mine is studied. The results show that the cumulative operators experience has converged to solutions near to optimal makespan. [ABSTRACT FROM AUTHOR]

Varieties of kaolin ore were sampled from a sedimentary deposit in Pará state and processed in a pilot plant for spectrocolorimetry studies. The aim was to provide a tool for the mining and processing operations. Ores like that contain textural and mineralogical variations that define whether the ore blocks may or may not be processed. The decision making depends, first, on the ore color subjective analysis: reddish blocks are inappropriate, but the whitish ones are appropriate. The ore color depends on the mineral paragenesis contaminant. Fifteen representative samples of five varieties of kaolin were analyzed under different parameters. These samples were visually defined by the ore color. The reflectance curves of the sandless product defined seven spectrocolorimetric groups, four of which were appropriate for generating a quality product for the market. This study presents both the analyses and the results for each group, what they represent as a tool to support the mining and processing operations, and some considerations about the blending among the kaolin groups. [ABSTRACT FROM AUTHOR]

Reconciliation can be divided into stages, each stage representing the performance of a mining operation, such as: long-term estimation, short-term estimation, planning, mining and mineral processing. The gold industry includes another stage which is the budget, when the company informs the financial market of its annual production forecast. The division of reconciliation into stages increases the reliability of the annual budget informed by the mining companies, while also detecting and correcting the critical steps responsible for the overall estimation error by the optimization of sampling protocols and equipment. This paper develops and validates a new reconciliation model for the gold industry, which is based on correct sampling practices and the subdivision of reconciliation into stages, aiming for better grade estimates and more efficient control of the mining industry's processes, from resource estimation to final production. [ABSTRACT FROM AUTHOR]

Several mining companies operating in Brazil have been preparing mine closure plans describing end of life actions to ensure long term physical stability, land rehabilitation and, to a certain extent, socioeconomic measures. Most Brazilian and international guidelines, however, skip early closure and only feature guidance to closure planning after reserve depletion. In this paper, two cases of early closure in Australia are reviewed, causes for early closure are explored, criteria to evaluate preparedness to early mine closure are proposed and tested in two mines. It concludes that, despite recent advances, planning for mine closure seldom take account of early closure risks. [ABSTRACT FROM AUTHOR]

This work addresses open-pit mining operational planning with dynamic truck allocation. The problem involves determining the number of trips that each mining truck would do to each mining face, as well as deciding to which face the shovels are to be allocated, in order to meet the production and quality targets, and to achieve the best utilization of the available fleet. Due to the combinatorial complexity of the problem, it is solved using a heuristic algorithm based on the Iterated Local Search metaheuristic. The proposed algorithm is tested using real data and the results are compared against those produced by a LINGO-based mathematical programming model. [ABSTRACT FROM AUTHOR]

Even with the financial crisis of 2008, the steel consumption forecast for the BRIC countries - Brazil, Russia, India and China - is for a significant increase over the next decades, due to their present low per-capita consumption level. The start up of new mines to supply this increase in demand is likely to be limited due to legal and practical restrictions related to environmental, social, manpower and energy issues. Therefore, most of the new demand for iron ore will be supplied by increasing the productivity of mines currently in operation. The main challenges for managing mine productivity are related to the choice of the estimation method, due to the difficulties in collecting appropriate information and to the establishment of a representative model. This article presents an estimation approach for mine productivity estimation through multiple regressions over the operational database of the mine. The approach is proposed through a Mine Productivity Estimation and Management tool (MPEM) which can deliver savings related to increased production efficiency by the identification and removal of losses in the mine production flow. Production improvement has been actually achieved in practical applications by managing the discrepancies in the KPIs of different operating shift crews. The operational variables have been identified directly over the operational database of the mine and the model has been developed in a simple and easy-to-use fashion, with excellent levels of correlation between the estimated and actual values of the mine's productivity. The article describes the development approach as well as the application of the model in a case-study. [ABSTRACT FROM AUTHOR]

The water absorption of ceramic tiles is a basic parameter for its classification. In this paper the water absorption was studied in red clays of the Corumbataí Formation to verify the influence of the particle size distribution and mineralogical composition in four different samples of clays through the evolution of the sintering with the increase of the temperature. Mixtures of raw materials were prepared by the contribution of each one. It was based on the individual absorption of water to get prefixed water absorption for the mixture. The causes of the experimental variations were analyzed in relation to the expected value, to make corrections in the composition or temperature, allowing larger control on the products. The acquired packing for a constant compaction density of the test specimens and the mineralogical composition, responsible for the content of fluxing compounds, were effective to justify the observed ceramic behavior. [ABSTRACT FROM AUTHOR]

The Brazilian Mining Code defines mining as the set of operations required for the industrial exploitation of a mineral deposit, which includes mining and processing. In order to obtain a Mining Permit, such operations should be presented in an Economic Exploitation Plan (EEP) which should demonstrate the technical and economic feasibility of mining a deposit. Since 2002, the inclusion of a mine closure plan in the EEP has been a requirement, as the NRM-20. This study investigated the applicability of this requirement's inclusion in the EEP from proposals presented to DNPM. Thirty EEPs were analyzed after the publication of the NRM. Although it is a requirement of NRM-20, this study demonstrates that no one of the studied mines had a closure plan included in the EEP, or thereafter, as an update. And, that those EEPs were approved and the mining permit granted. Even with no closure plans included, 14 EEPs presented some closure cost for economic analysis. In these, the Estimated Closure Cost (ECC) had greatly dispersed values. On the other hand, in 16 EEPs there was no cost estimate associated with mine closure. This study highlights the lack of government guidelines for the evaluation of EEPs focused on a mine closure plan. And, that the mining companies fail to consider the hiring of consultants for closure plan design as a mine closure cost. [ABSTRACT FROM AUTHOR]

The mining and processing industries of laminated calcite tile are an important economic sector in the State of Ceará. However, they generate a large amount of wastes, which are a source of contamination and environmental pollution. This study aimed to characterize the laminated calcite tile sawing waste and evaluate its suitability as an alternative ceramic raw material for the production of bricks and roof tiles. The waste was characterized by chemical composition determination, X-ray diffraction, differential thermal analyses, particle size distribution determination, and morphological analysis by electronic scanning microscopy. Several formulations were prepared and sample bodies were prepared by uniaxial pressing. The sample bodies were fired at different temperatures. Sintered samples were characterized in terms of water absorption and mechanical strength. The results showed that the waste is composed of calcite and dolomite, that presents a high level of fines. As such, it is possible to incorporate up to 10% for the production of ceramic bricks and roof tiles. [ABSTRACT FROM AUTHOR]

This study investigates geophysical logging as a tool to predict coal quality. Some of the coal's chemical parameters were determined by laboratory analysis and were compared against values derived from geophysical logging correlation (natural gamma radiation and resistivity versus ash content, specifically). The results showed a strong correlation between the coal's natural gamma emissions and their ash content. From this correlation, a simple linear model was obtained and used to estimate ash grades, directly from geophysical logging records. The error of these predictions is less than ± 5%. Additionally, results showed no correlation between the sulphur grade, or volatile matter, and the geophysical records. Ash grades derived from natural gamma ray values can be usedas secondary information to evaluate coal quality during resource estimation, when combined with lab analysis and appropriate geostatiscal methods. The methodology is illustrated by means of a case study at a coal deposit located in southern Brazil. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the respiratory protective device selection process and to identify changes in this process when an exposure limit value is updated. Two previous studies conducted in mining industries in the metropolitan area of São Paulo were put through the respiratory protective device selection process. The protection factors of the equipment provided by the companies were compared with the required protection factors and with the FUNDACENTRO's respiratory protection program. The results showed that until 2005, some companies were providing inadequate protection, and after the change in crystalline silica exposure limit value in 2006, all the analyzed companies were providing inadequate respirators. This study suggests that there is an opportunity to create a web portal, where the selection process can be done by the companies with updated information. [ABSTRACT FROM AUTHOR]

Located in the valleys of the Ribeira de Iguape and Paranapanema Rivers, where karst features and a large number of caves can be found, the Intervales State Park and its buffer zone lie within an area of Proterozoic carbonate rocks that are of great interest to the mining industry. Based on geomorphological and geological studies, the characterization of the karst was performed in order to develop a management plan for the Intervales State Park and its buffer zone. With this, it was possible to define the degree of vulnerability of the karst aquifer to contamination. The areas of greatest vulnerability are those that facilitate injection of contaminants directly into the aquifer, being characterized by such karst features as caves and sinks. In regions where recharge occurs exclusively via diffuse infiltration, and runoff convergence with surface watercourses, the degree of vulnerability is lower. Considering this analysis, areas with the greatest impact potential were identified and recommendations made regarding management of the park and its buffer zone. [ABSTRACT FROM AUTHOR]

One of the major challenges for the mining industry is to supply the processing plant with ore that meets its specifications for maximizes production. This can only be achieved if proper knowledge of the geological domains of the orebody is acquired. However, this condition is not sufficient: once the geological domains of the orebody are properly known, it is also necessary to model the geological grades using estimation techniques such as kriging. The challenge for mining companies is to establish sampling processes and techniques that allow the appropriate estimation of the geological grades of the mined out ore. This paper presents a comparative analysis between three sampling methods and their impact on the estimation of the geological grade at the mine face in a case study carried out at the Cajati mine of Bunge Fertilizantes S/A, located in Sao Paulo, Brazil. [ABSTRACT FROM AUTHOR]

The effectiveness of environmental reclamation measures implemented in limestone mines is reviewed. An assessment procedure developed by Neri and Sánchez (2008) was used. This tool comprises a set of statements of good practice grouped in three categories (essential, important and accessory practices) which are assessed through (i) carrying out field technical inspections guided by a series of protocols especially designed for this purpose; (ii) classifying inspection evidences according to previously defined categories (totally applied or satisfactorily adapted, partially applied, not applied or not applicable); and (iii) calculating conformity indexes. The results showed that: planning activities featured the lowest performance (low conformity indexes), operational practices reached the most satisfactory results and management practices medium conformity indexes. A general conclusion is that in these mines, current practices are partially effective in establishing favorable conditions for long-term success of rehabilitation. Improvements in planning practices could significantly enhance performance and reduce risks. [ABSTRACT FROM AUTHOR]

Recent investments in mineral exploration and production projects such as those of petroleum, copper, iron and manganese have been financed by two or more companies. This is essentially a strategy of financial risk diversification, by sharing a portion of the investment, but on the other hand, getting also a portion of the net profit. This paper is focused on a model for estimating the optimal working interest considering in an integrated way the project risk, the corporate financial condition and the risk attitude of decision-maker by the use of utility functions, a tool for choices under uncertainty. Results from traditional approach are divergent from those of this methodology, especially in the case of risky cash flows and if the project investment is high compared to the corporation budget. The methodology present in this paper is an important step in the process of an efficient resource allocation and value creation for corporation's stockholders, regarding their risk tolerances. [ABSTRACT FROM AUTHOR]

The article offers information about the risk management software RISKGATE for mineral industries developed by the Sustainable Minerals Institute/Minerals Industry Safety and Health Centre of the University of Queensland, Australia.

An introduction is presented in which editor discusses the publication of the journal.