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Hydrogen has the potential to become a powerful energy vector with different applications in many sectors (industrial, residential, transportation and other applications) as it offers a clean, sustainable, and flexible alternative. Hydrogen trains use compressed hydrogen as fuel to generate electricity using a hybrid system (combining fuel cell and batteries) to power traction motors and auxiliaries. This hydrogen trains are fuelled with hydrogen at the central train depot, like diesel locomotives. The main goal of this paper is to perform a techno-economic analysis for a hydrogen refuelling stations using on-site production, based on PEM electrolyser technology in order to supply hydrogen to a 20 hydrogen-powered trains captive fleet. A sensitivity analysis on the main parameters will be performed as well, in order to acquire the knowledge required to take any decisions on implementation regarding electricity cost, hydrogen selling price, number of operation hours and number of trains for the captive fleet.The main methodology considers the evaluation of the project based on the Net Present Value calculation and the sensitivity analysis through standard method using Oracle Crystal Ball. The main result shows that the use of hydrogen as an alternative fuel for trains is a sustainable and profitable solution from the economic, environmental and safety points of view.The economic analysis concludes with the need to negotiate an electricity cost lower than 50 €/MWh, in order to be able to establish the hydrogen selling price at a rate higher than 4.5€/kg. The number of operating hours should be higher than 4800 h per year, and the electrolyser system capacity (or hydrogen refuelling station capacity) should be greater than 3.5 MW in order to reach a Net Present Value of 7,115,391 € with a Return of Investment set to 9 years. The result of the multiparametric sensitivity analysis for the Net Present Value (NPV) shows an 85.6% certainty that the project will have a positive result (i.e. profitability) (NPV> 0). The two main variables with the largest impact on Net Present Value are the electrolyser capacity (or hydrogen refuelling station capacity) and the hydrogen selling price. Moreover, a margin of improvement (higher NPV) could be reached with the monetization of the heat, oxygen by-product and CO2 emission reduction.

Rendering the energy system more sustainable can only be achieved through a combination of low-carbon energy production, energy efficiency, and coupling of energy sectors. In this context, Power-to-Hydrogen concepts for managing supply and demand, providing seasonal storage, and being the linking element between different sectors (electricity generation, gas grids, transport and industry), has attracted significant interest during the last decade. However, the deployment of technology is subject to legal barriers, which may differ from one region to another. On the contrary, there may be incentives to facilitate market introduction of a new technology.In this paper, an international network of experts under the umbrella of Task 38 of the International Energy Agency's Hydrogen Technology Collaboration Programme assesses the legal framework in ten countries regarding power-to-hydrogen applications. The most frequently considered pathway, from a legal standpoint, is using hydrogen for mobility applications. Only a few countries are implementing legal frameworks for diverse hydrogen applications. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Even though semiautogenous grinding mills and ball mills are normally used in grinding processes, the industry is driven to decrease cost by increasing efficiencies and decreasing energy consumption. High Pressure Grinding Rolls (HPGR) are seen as an energy-efficient alternative but their developments in modeling and control have received relatively little attention. In this work a model and a control scheme for HPGR is presented that considers the total energy consumed as one of the main controlled variable. First, the model was generated by using literature-reported information of a specific manufacturer and lithology. The dynamic representation of the treatment capacity, product granulometric distribution (reported as 80% percentile), compression energy, and rolling energy were considered as the most important model output variables. Second, model validation was performed with considerable positive results (based on assessment of estimation errors). Finally, the model was used to generate a multiple input multiple output control scheme. As result, it was observed that the model had a correct representation of the phenomena involved and that the peripheral velocity and pressure used in the HPGR are useful manipulated variables to control the energy consumed by the equipment in an MPC scheme.

Chile cuenta con grandes ventajas para conformar una nueva economia industrial-minera, basada en energias limpias, procesos innovadores, rentables y con baja huella de carbono. Una de las alternativas energeticas a considerar es el hidrogeno. Con las condiciones de entorno de Chile, es posible producir hidrogeno renovable a precios muy competitivos. Este hidrogeno podria utilizarse a nivel nacional, como combustible limpio o como materia prima industrial para diferentes aplicaciones. El uso de este elemento permitira limitar las emisiones de gases de efecto invernadero y gases contaminantes a la atmosfera. Tambien, posibilitara la disminucion de la dependencia del pais de recursos energeticos externos y la reduccion de la dependencia externa del pais de materias primas quimicas, como es el caso del amoniaco.

Continual growing demand for metals in regular and emerging markets has led to an increasing use of chemicals and reagents in ore processing. This trend force to incur in an increasing use of commodities which inevitable leads to higher operational costs and environmental concern. The chemicals and reagents used in flotation processes especially invoke high costs of handling and disposal due to their hazardous nature, but until now, few studies have been carried out to seek possible alternatives. In order to develop a cheaper and greener processes, these hazardous materials should be replaced by more sustainable products, by-products, or wastes generated by other industries. Biosolids, cheaper and greener than chemical frothers and collectors, have been tested successfully in flotation processes. Studies of removal rates and froth flotation kinetics have been carried out independently, nevertheless a deeper understanding of the tradeoffs involved between the rates and kinetics should be obtained. This work evaluates the use of different collectors (conventional collector (CC), biosolids (and their main components), and mixtures of CC and biosolids main components) in the froth flotation of copper sulfide ores. Tests were carried out in Denver Cells, at fixed collector, frother, and pH levels, in order to estimate metallurgical and kinetic parameters. In rougher flotation tests, biosolids show to be the most efficient non-CCs, achieving Cu recoveries of 64.1%. CC achieved 76.2% Cu recoveries while none of the pure biosolids main components achieved Cu recoveries over 60%. In the kinetics studies, only the partial replacement of CC (by 50% of Humic Acids (HAs) or biosolids) allowed a similar copper recovery once compared with CC (~81% Cu to be obtained with a fast kinetic constant of ~0.88 min-1). For molybdenum, partial replacement of CC produced better recovery and kinetics constants (k of 0.83 min-1 and R∞ of 66.10% for 50% CC - 50% HAs; k of 0.90 min-1 and R∞ of 61.79% for 50% CC - 50% biosolids). Results show that different combinations of biosolids - CC or HAs - CC could achieve optimal flotation conditions. As evaluated, an optimal combinations would allow considerable reductions in energy and chemical consumption.

High Pressure Grinding Rolls (HPGR) technology has been considered as an alternative in the mining industry. This consideration has been given by its energy efficient characteristics (i.e. lower energy consumption compared to other types of technologies. such as semiautogenous technologies). Mathematical models that describe the behavior of this equipment are used to evaluate and predict yields (in terms of granulometric distribution), nevertheless their use and consideration for control processes is scarce. The present work focuses in the development of a dynamic representation of a HPGR unit, and the control of it, by considering a first order kinetic representation of the grinding process and the total energy consumed by the HPGR as the main controlled variable. The model considers a dynamic evaluation of the rolls peripheral velocity, the operational gap, and the feed mass flow as manipulated variables (the first two can be directly correlated to energy) while the density in the extrusion zone and the 80% size percentile were selected as the controlled variables. As result, it was observed that the model has a correct representation of the phenomena involved and that the selected variables are useful manipulated variables to control the energy consumed by the equipment.

The productivity of the mining industry in Chile, currently the main driver of Chilean economy, is closely tied to foreign demand for ores. Ore-processing is known for involving energy–intensive processes, such as comminution, concentrating and cathodic processes. As mining activities take place in the arid north of Chile, they are affected by water scarcity. Water shortage has forced the industry to pump desalinated seawater up to mining sites over 2000 m above sea level, further increasing electricity consumption. Given these energy needs, and the fact that electrical energy supply in the north of Chile is based on fossil fuels, it is important to consider the use of renewable energies as environment-friendly and economic alternatives. The aim of this work is to evaluate, by an optimized techno-economic analysis, the use of photovoltaic and a novel wind-based technology to supply at least 10% of the current and the predicted electrical energy requirements of the mining industry in the Antofagasta region. A combination of an optimization problem and technical evaluation was performed using Matlab to obtain the optimal number of solar and wind-based technology units in a case study. Total energy generation from a novel wind-based technology unit is 67,616 MWh/y, corresponding to 14.45·10 6 Nm 3 (1298 t) of hydrogen and 7.41·10 6 Nm 3 (10,323 t) of oxygen after electrolytical transformation. Considering a 65% efficiency of the combined cycle fed with hydrogen and oxygen, 28,133 MWh/y of electrical energy would be obtained. For the cases studied the cost of energy from the combined system was estimated to be between 0.255 US$/kWh and 0.273 US$/kWh, slightly higher than the average energy regional cost. According to the analysis, the renewable energy system could be a sustainable alternative to supply economic green energy to the mining industry in Chile.

There are currently two technologies that dominate the current trends of electric vehicles: fuel cell and battery. Both options generate electricity to drive electric motors, eliminate pollution and improve vehicle efficiency. Fuel cells derive their energy from hydrogen stored in the vehicle, while the batteries get the energy from grid. The two forms of electricity generation have advantages and disadvantages in terms of power density and energy density, dynamic response, refueling time, autonomy and the possibility of regenerative braking, infrastructure for recharging.The electric vehicle configuration will consist of a series of blocks that must give the system a performance similar to the conventional configuration in the same terms of speed, acceleration, time of refueling and comfort.This paper develops the analysis of current technology in the propulsion system of electric vehicles for further optimal sizing of components and systems that make the same fundamental, a study of the most appropriate for the use of either technology .