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The paper presents an experimental study on the formation process of burden surface texture on the blast furnace throat and its influence on the radial distribution of gas flow. The study was performed with the application of blast furnaces equipped with a bell-type charging device using radio-isotope means for the control of burden surface texture (profile) and burden surface level, i.e., gamma locators for burden surface texture. The study was carried out under the conditions of an operating blast furnace in an iron and steel plant using a unique GEOTAPS system for automated control of geometric and temperature parameters of burden material surface on the blast furnace throat. The influence of the surface texture on the gas flow distribution was also investigated. The possibility of a self-stabilization effect for burden surface texture and gas flow in an operating blast furnace under suitable conditions was experimentally proven. As a result of the experimental study performed, four ways of energy-saving technology implementation were determined for the control of blast furnace melting based on the data on the burden surface texture and previously unknown regularities of surface layer formation of burden material on the throat of an operating blast furnace with a bell-type charging device. The main idea of the paper is the development of automated control for the radial distribution of burden material and gas flow using actual or predicted surface texture parameters as important intermediate factors that both describe the process and have a significant simultaneous influence on it.

Environmental pollution as the result effluents discharged by industry is increasing, principally owing to mixtures of pollutants, including dyes. The objective of the present study was to evaluate the adsorption process of the bicomponent mixture of Tartrazine (Y5) and Brilliant Blue FCF (B1) dyes in a dynamic regime (fixed-bed column), using rice husks (RH) as adsorbent material. A 3-level response surface design of experiments was employed to evaluate the adsorption process of the dyes in the mixture at the following initial concentrations: 0.0216, 0.0739, 0.1261, 0.1477 (mmol L−1). The response surface analysis of the experimental design made it possible to identify a competitive adsorption of both dyes. RH had higher affinity for B1, although the adsorption capacity changed depending on the concentration of each dye in the mixture. The highest RH adsorption capacity was 3.4 mg g−1 for B1 and 1.45 mg g−1 for Y5, respectively, under a monocomponent condition. It was considered that the interactions in the mechanism proposed for the adsorption process occurred because of the formation of hydrogen bonds between the sulfonate groups of the dyes and the –OH groups present on the surface of the adsorbent. B1 had a higher affinity towards RH because it had one more sulfonate group than Y5. The multiple-response optimization results make it possible to recommend the use of RH beds with low concentrations of B1 and Y5 in the same feed.

The Galapagos Islands have been declared a World Heritage site due to their unique biodiversity, which makes them a living museum and a natural laboratory for humankind. However, to fulfill the energy needs of its habitants and foreign visitors, the islands have depended on fossil fuel energies that have produced levels of lead and chemical agents that are affecting the islands’ air quality, flora, and fauna. Therefore, zero-carbon initiatives have been created to protect the islands, wherein solar and wind power plants have been studied as reliable alternatives. In this way, Geographical Information Systems based on Multicriteria Decision Methods constitute a methodology that minimizes the destruction and disturbance of nature in order to assess the best location for the implementation of these alternative energy sources. Therefore, by exploring the geographical information along with the Analytical Hierarchical Processes and the Ordered Weighted Average methods, it was possible to identify the potential for solar power plants of 10 MW on each island; likewise, for wind power plants, it was found that the islands possess implementation potential that has been analyzed in the field, showing that the best location is on Baltra Island, but is not limited to it.

The growing demand for electric power and the need for an energy transition that contributes to the reduction of global greenhouse gas emissions have driven the development of various energy generation, storage, and offset technologies. These technologies are known as distributed energy resources. Their integration into distribution power systems not only contributes to improving operating aspects, but also allows supplying electricity to areas that do not have access to large-scale power systems. Therefore, the integration and management of these resources has become a topic of interest, and several studies seek to optimize their impact on technical, economic, and environmental aspects. However, this optimization poses specific challenges related to the type and number of variables related to the operation of a distribution power system. This review article aims to describe the main challenges posed by three-phase AC three-phase distribution power systems under scenarios involving the integration of distributed energy resources. In addition, it presents some approaches proposed by different authors to improve the technical, economic, and environmental aspects of power grids. It can be stated that the strategies presented in the literature fail to consider scenarios that simultaneously integrate different types of technologies and optimize them while following a multi-objective approach and considering three-phase systems in a context of variable generation and demand. Therefore, future work in this field should address these aspects in a holistic manner, taking into account the computation efforts and processing times required by intelligent algorithms.

We examine the possibility of making useful climate extrapolations in inner basins. Stressing the role of the local geographic features, for a practical example we focus our attention on the Red Sea. We observe that in spite of being an enclosed and relatively small Sea, its climate conditions are heavily affected by those of the larger neighboring regions, in particular the Mediterranean and the Arabian Seas. Using existing high-resolution information of the recent decades, we use both reasoned extrapolation and knowledge of, past and future, longer term general climatic information to frame what is presently possible to assess for the Red Sea. Specifically, the northern part, influenced by the Mediterranean Sea, shows a clear decreasing trend of both the meteorological and wave conditions in the recent decades. However, within a longer span record of 100 years, this decrease appears to be part of a 70-year cycle, which may be overturning, partly at least, in the coming decades. These trends are consistent with the expectations inferred from regional climatic indices, such as North Atlantic Oscillation and Atlantic Multidecadal Oscillation. No similar long term trend has been found for wave, hence implicitly the wind, conditions in the southern part of the basin. As expected, some correlation exists with the typical patterns of the Indian Ocean, but without any specific indication of a future trend. We suggest that, suitably adapted for the specific local conditions and dominant patterns, similar correlation and physical patterns may exist in several of the enclosed areas of the world, opening the possibility of exploring their possible trends in the future decades.

The use of environmentally friendly deep eutectic solvents (DES) in green synthesis of different types of nanoparticles has garnered increasing interest in recent years. The application of these materials in water treatment, mainly by adsorption or degradation, is emerging as a sustainable alternative to conventional methodologies. However, the information about the green synthesis of nanoparticles (NPs) using DES is dispersed in the literature. This review is focused on compiling and systematizing information regarding DES-mediated NP synthesis, the application of these NPs in water treatment, and future perspectives of these technologies. DES represent an excellent alternative to traditional solvents in NP synthesis due to their low toxicity, low cost, and being environmentally friendly. The possible NP surface functionalization with DES is also attractive as it plays a pivotal role in processes related to water treatment. Modification and synthesis of carbon nanotubes, graphene oxides, magnetic iron oxides, among others, for the adsorption and degradation of organic dyes, pharmaceuticals, metal ions, herbicides, pesticides, and other water contaminants found in recent literature are presented in this work. Finally, the possibility to control NP size and shape can be helpful in the design of new materials for a specific application.

Solar photovoltaic (PV) energy systems are one of the most widely deployed renewable technologies in the world. The efficiency of solar panels has been studied during the last few decades, and, to date, it has not been possible to displace the production of energy using crystalline silicon wafer-based technology whose efficiency has reached values around 26.1%. Moreover, using solar tracking PV systems has become a feasible alternative to increase the electric output of PV silicon technologies instead of using the conventional fixed PV installation on a flat or sloping surface. The following study has compared fixed and dual-axis sun-tracking PV panels in order to quantify the enhancement associated with the amount of energy harvested when using dual-axis tracking PV systems in the city of Manta, located in a coastal region of Ecuador. In order to carry out this study, an IoT monitoring system based on Raspberry Pi3 and Arduino platforms was used. Measurements of solar radiation (W/m2), light intensity (Lux), temperature (°C), short-circuit current (A), and open-circuit voltage (V) were taken every minute for both systems. The results prove that the dual-axis tracking PV system produces, on average, 19.62% more energy than the static PV system. These results present an 8.62% energy increase with respect to a previous study carried out in an equatorial region with similar characteristics to those of the city of Manta, where a one-axis tracking PV system was used.

Sustainable development reached a new energy paradigm in recent decades, by promoting renewable generation technologies. The present study performs a techno-economic analysis of several hybrid energy systems that combine wind generators, photovoltaic systems, hydrokinetic turbines, lead acid batteries, and diesel generators in southern Ecuador. From real data, the sizing optimization of each renewable system was done under three proposed energy control algorithms. Then, the combinations of renewable systems are compared based on costs, energy, and environment. Additionally, this study includes several sensitivity analyzes varying the cost of the components and fuel, minimum state of charge in batteries, scaled electric load and time step to better understand the impact caused in each renewable hybrid system. The results show that a system composed of three renewable sources under load following and cycle charging energy controls, is cheaper and less polluting with respect to any combination of sources proposed. In addition to this, the systems that include photovoltaic systems and diesel generators present lower cost, 0.36 US$/kWh in the best case. To reduce the operability of the diesel generator, load following energy control is recommended. However, if diesel generator is removed, the resulting cost of 100% renewable systems increases considerably, reaching 0.88 US$/kWh. The results also show that, the variation in the capital cost of the components is directly proportional to the net present cost and cost of energy variation. Moreover, it is possible to reduce the cost of the system by discharging the batteries below their minimum state of charge. Finally, the results are more accurate when using a time step of 5 minutes.