Explore the vast range of titles available.

Explores the changing character of industrial relations and labour processes in two staple industries, potash and uranium mining, through an innovative case-analytic approach that compares the managerial strategies used by five transnational firms.

Potash mining is an important economic activity in the north-east of Spain. However, one of the main environmental issues produced for such type of mining is subsidence, which generates horizontal and vertical ground displacements. A Geographic Information System (GIS)-based model is proposed as a management system in a case study with two mines. This system is able to deal with subsidence data and its behavior over time. More than 1300 control points are included in the GIS, with data since 2007. These data processed by the GIS allowed determining the module, sense and direction of the displacements, the sinking velocity and the possible affectation of subsidence to infrastructures and buildings. Hence, the system created can be a useful tool to manage subsidence data, determine its evolution, predict future environmental and social impacts and control corrective measures.

The friction factor is an essential parameter to take into account for modelling the ventilation system. One of the principal features that define the friction factor is the roughness, which not only does it have influence on the airway resistance, but it has also a direct bearing on the rate of heat transfer between the rock and the airstream. In this paper, the characteristic friction factors of a potash mine exploited using a room and pillar method has been determined by means of the Chezy-Darcy and Atkinson equations. The results give an impulse to achieve standardized friction factor values in potash mines very useful for future mining ventilation surveys.

Increasing energy costs and the need to conserve energy compounded with low mineral prices have prompted some Canadian mines especially potash producers, to examine their operations and identify potential saving methods. Re-using or recirculating a fraction of ventilating air may enable these mines to reduce winter heating costs. Gas and dust concentrations were monitored in the intake and exhaust airways to assess the potential for recirculating exhaust air. The results indicate that the mine pollutant concentrations in potash mines are low and stable. Trial recirculation experiments returning 20-47% exhaust air into the fresh air airway did not cause signficiant increases in mixed intake pollutant levels. Two types of recirculation systems--namely variable and fixed quantity--are developed. Detailed designs of recirculation systems for Central Canada Potash of Noranda Minerals Inc. and Rocanville Division, Potash Corporation of Saskatchewan are discussed and recommendations made for the selection and positioning of on-line monitoring, control and telemetry systems. A controlled recirculation system conceptual design for the H-W mine is given. The economic payback periods for systems proposed for Rocanville Division and CCP are 2 and 3 years respectively. Recirculation percentages of 30%, 64.4% and 23% are feasible for CCP, Rocanville Division and the H-W mine. The recirculation percentages for the proposed systems were determined using Air Quality Index criteria. Dust deposition studies conducted at CCP in return airways indicate that 65% of dust by weight is deposited within a distance of 550 metres from the face. In terms of dust and other contaminant conditions in the return airways, it can be concluded that there is potential for use of recirculation in the face area. Guidelines for recirculation systems in gassy and dusty mines are developed. The main features for these recirculation system design guidelines are safety, economic gain, and system performance. The author's contribution to ventilation is in the use of controlled recirculation to reduce winter heating costs and increase underground airflow, also the guidelines developed for recirculation in gassy and dusty mines. The overall conclusion is that controlled recirculation is a practical method of reducing winter heating cost and/or increasing mine airflows. The financial potential and technology to implement a working system exist.

Humanity development is associated with higher spiritual and social behaviour and financial shape, which is an undeniable factor of urbanisation. Previously, in areas of georesource concentration, cities and settlements were formed with people exploiting these georesources. However, imperfect technologies lead to rapid depletion of reserves and industrial and environmental disasters, which affect the vulnerability of cities and the people living in them. The analysis of applied technologies has demonstrated that potash extraction is accompanied by a low recovery ratio, high mine accidents, and environmental problems. The principles of sustainable development of geo-resources for the creation of mining technologies that ensure industrial safety, environmental sustainability, and extending the life of the mining enterprise to save working places will reduce the vulnerability of cities. This article proposes the use of the room-and-pillar mining method with the replacement of natural supports with artificial ones. Three-stage stoping with backfill is considered. Numerical modelling has shown stabilisation of mining and geomechanical processes, which confirms the prospectivity of the method with backfill. For these purposes, this research presents a new backfill composition based on local industrial waste. Schemes of backfill preparation and feeding into the mined-out space are proposed. The proposed technology, based on the principles of sustainable development of georesources, is the foundation for an economically profitable, environmentally friendly, and socially responsible mining enterprise. The implementation of the principles of sustainable development of georesources will allow for the preservation of cities and reduce their vulnerability.

This paper investigates the flow performance and mechanical properties of underground gelled filling materials made from potash mine tailings, using lime as a gel. It demonstrates the feasibility of using lime as a gel, potash mine tailings as aggregate, and replacing water with potash mine tailings to create filling materials that meet design requirements for flow and compressive strength. The role of lime in the hardening process is explored through X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and infrared analysis. Results show that hydration products vary with lime dosage. With 9% lime (L9), the products are primarily ghiaraite (CaCl2·4H2O) and carnallite (KMgCl3·6H2O); with 5% lime (L5), tachyhydrite (CaMg2Cl6·12H2O) predominates, along with minor amounts of antarcticite (CaCl2·6H2O) and korshunovskite (Mg2Cl(OH)3·4H2O); and with 2.6% lime (L2.6), the products include tachyhydrite, ghiaraite, bischofite (MgCl2·6H2O), and korshunovskite. These hydration products form a dense, interwoven structure, enhancing the strength of the filling material. This study offers a theoretical foundation for using lime gel as a filling material in potash mining, with significant implications for sustainable mining practices.

Potash fertilizer production is one of the most important economic activities. Historically, potash mining has had a significant impact on the environment, often with catastrophic consequences. The purpose of this paper is to summarize the results of studies on the environmental impact of potash mining using the example of the Verkhnekamskoe potash deposit. The deposit is located in the central part of the Solikamsk depression in the Pre-Ural foredeep (Perm Krai, Russia). All the main features and problems of underground mining of water-soluble ores and potassium fertilizer production are considered using the example of one of the world’s largest potash deposits. This paper looks into the specifics of the material composition of waste, its disposal, underground mining issues associated with the solubility of salts, and the risks of groundwater inflow into the mine workings, which causes flooding of mines. The results of all surveys show that potash mining affects the atmosphere, surface water, groundwater, soil, and vegetation. The most effective measure to reduce the adverse environmental impact of potash mining at the Verkhnekamskoe Deposit is hydraulic backfilling of mine chambers, which protects the underground mines from flooding, minimizes ground subsidence, and reduces the area of potash waste.

To reduce intensity of deformation in rocks prone to buckling and plastic deformation, and sensitive to geo- and gas-dynamic phenomena, the authors propose a consolidated backfill technology using salt waste and processing reuse brine at the consumption limits of water-yielding capacity. A set of laboratory tests is carried out to find backfill mixtures adaptable to deep-level potash mining with estimation of deformation characteristics and strength properties of potash salt rocks. New principles and technologies of deep-level sylvinite extraction and backfill material transport by creating such geotechnical structures in stopes which ensure formation of consolidated backfill mass with the mined-out stope space factor close to one. This approach can enhance mine efficiency owing to increased extraction of sylvinite from rib and safety pillars.

The advent of digital mining has become a tangible reality in recent years. This digital evolution requires a predictive understanding of key elements, particularly considering the reliable communication infrastructures needed for autonomous machines. The LoRa technology and its underground propagation behavior can make an important contribution to this digitalization. Since LoRa operates with a high signal budget and long ranges in sub-GHz frequencies, its behavior is very promising for underground sensor networks. The aim of the development and series of measurements was to observe LoRa’s applicability and propagation behavior in active salt mines and to detect and identify effects arising from the special environment. The propagation of LoRa was measured via packet loss and signal strength in line-of-sight and non-line-of-sight configurations over entire mining sections. The aim was to analyze the performance of LoRa at the macroscopic level. LoRa operated at 868 MHz in the free band, and units were equipped with omni-directional antennas. The K+S Group’s active salt and potash mine Werra, Germany, was kindly opened as a distinctive experimental setting. The LoRa exhibited characteristics that were highly distinctive in this environment. The presence of the massive salt allowed the signal to bounce along drift edges with near-perfect reflection, which enabled travel over kilometers due to a waveguide-like effect. A packet loss of below 15% showed that LoRa communication was possible over distances exceeding 1000 m with no line-of-sight in room-and-pillar structures. Measured differences of Δ50dBm values confirmed consistent path loss across different materials and tunnel geometries. This effect occurs due to the physical structure of the mining drifts, facilitating the containment and direction of signals, minimizing losses during propagation. Further modeling and measurements are of great interest, as they indicate that LoRa can achieve even better outcomes underground than in urban or indoor environments, as this waveguide effect has been consistently observed.

Subsidence is one of the main environmental impacts of underground mining worldwide. Besides, the increasing complexity of underground mining due to greater depths and interaction with inhabited and environmentally sensitive areas can lead to challenges that may threaten the viability of mining due to phenomena such as subsidence. This research aims to increase the knowledge about surface subsidence due to underground mining, characterising the main factors that rule mining subsidence utilising an actual mine that extracts potash. The calculation methodology was based on 74 sections of the subsidence basin, using GPS measurements and the InSAR technique, with data collected over twelve nonconsecutive years from 1995 to 2021. Thus, three different active areas and one residual area were determined. Average boundary angles and their average distances of influence for the active regions have also been determined. Furthermore, using the least squares method, the subsidence basin curve was defined using a Gaussian function. The algorithm that governs the subsidence process has been successfully calculated, allowing the approximation of the deformation of any point within an area of interest. The novelty of this paper is twofold: the results obtained provide a detailed subsidence behaviour and a prediction model of the case study. Furthermore, the methodology implemented can be applied to other subsidence basins with mines in their area of influence. Hence improving the surface mining area’s safety levels and managing the environmental impacts.