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Mining activities are essential for a population's development; however, they also produce negative effects such as the production of waste, an impact on flora and water pollution. On the other hand, construction is one of the sectors which is most demanding of raw materials, with one of the main such materials being water. For this reason, this research evaluates the feasibility of incorporating water contaminated by mining waste into ceramic materials for bricks. In this way, the use of water is reduced and, on the other hand, the contaminating elements of the mining water are encapsulated in the ceramic matrix. To achieve this, the clay used and the contaminated water were first analysed, then different families of samples were conformed with different percentages of contaminated water. These samples were tested to determine their physical and mechanical properties. At the same time, leachate tests were carried out to determine that the ceramic material created did not cause environmental problems. The test results showed that the physical and mechanical properties of the ceramics were not influenced by the addition of contaminated water. On the other hand, the leachate tests showed that encapsulation of most of the potentially toxic elements occurred. However, the use of contaminated water as mixing water for ceramics could only be performed up to 60%, as higher percentages would leach impermissible arsenic concentrations. Accordingly, a new way of reusing water contaminated by mining activities is developed in this study, taking advantage of resources, avoiding environmental pollution and creating economic and environmentally friendly end products. [ABSTRACT FROM AUTHOR]

The construction sector is one of the most demanding sectors of raw materials in existence today. As a consequence, the extraction of these materials has a significant impact on the environment. At the same time, mining activities produce a series of wastes, in some cases with polluting elements, which must be treated to avoid pollution. Therefore, the use of mining waste for the conformation of new construction materials is an important environmental advantage, even more so when such waste is prevented from producing polluting leachates. Therefore, in this research, geopolymers are developed with mine tailings from the Linares lead mines, chemically activated with potassium hydroxide. For this purpose, different percentages of the alkaline activator were tested and the physical and mechanical properties of the conformed materials were evaluated. The analysis of the different conformed geopolymers determined the optimum percentage of potassium hydroxide for conforming the geopolymer with the best mechanical and physical properties. In addition, the concentration in the leachate of potentially contaminating chemical elements in the mining waste was estimated to be lower than those regulated by the regulations. Consequently, this research shows the development of a sustainable material for construction with mining waste and reduction of the environmental impact of traditional products. [ABSTRACT FROM AUTHOR]

Road construction is an activity that demands a significant amount of aggregates for bituminous mixtures. In addition, these aggregates must be of a suitable quality for use, even more so on high traffic roads. In response to this problem, and in order to avoid the extraction of new raw materials, research is being carried out using industrial waste as a substitute for conventional aggregates. In this way, the extraction of raw materials is reduced and landfilling of waste is avoided. However, these wastes must have certain properties and environmental advantages over natural aggregates. Otherwise, the use of waste would not be environmentally beneficial but would be more damaging to the environment. For this reason, this research evaluates the viability of using electric arc furnace slag as aggregates for bituminous mixtures, the main objectives being the determination of the characteristics of the by-product, the particularities and the critical points to be taken into account for its subsequent use in mixtures. At the same time, the environmental advantages of treating this waste to obtain a usable aggregate are evaluated in comparison with the processing of a natural aggregate. The results showed that electric arc furnace slags have a suitable chemical composition and excellent physical and mechanical properties for use in bituminous mixtures, even on high traffic roads. At the same time, it was determined that their use produces a considerable reduction in environmental afflictions. Therefore, it could be affirmed that the use of electric arc furnace slags in bituminous mixtures is recommendable as a way to develop more sustainable materials for construction. [ABSTRACT FROM AUTHOR]

The greater environmental awareness, new environmental regulations and the optimization of resources make possible the development of sustainable materials as substitutes for the traditional materials used in construction. In this work, geopolymers were developed as substitutes to traditional ceramics for brick manufacture, using as raw materials: chamotte, as a source of aluminosilicate, and biomass bottom ashes from the combustion of almond shell and alpeorujo (by-product produced in the extraction of olive oil composed of solid parts of the olive and vegetable fats), as the alkaline activator. For the feasibility study, samples were made of all possible combinations of both residues from 100% chamotte to 100% biomass bottom ash. The tests carried out on these sample families were the usual physical tests for ceramic materials, notably the compression strength test, as well as colorimetric tests. The freezing test was also carried out to study the in-service behavior of the different sample groups. The families with acceptable results were subjected to Fourier transform infrared (FTIR) analysis. The results of the previous tests showed that the geopolymer was indeed created for the final families and that acceptable mechanical and aging properties were obtained according to European standards. Therefore, the possibility of creating geopolymers with chamotte and biomass bottom ashes as substitutes for conventional ceramics was confirmed, developing an economical, sustainable material, without major changes in equipment and of similar quality to those traditionally used for bricks. [ABSTRACT FROM AUTHOR]

Cold in-place recycling with bitumen emulsion is a good environmental option for road conservation. The technique produces lower CO2 emissions because the product is manufactured and spread in the same location as the previous infrastructure, and its mixing with bitumen emulsion occurs at room temperature. Adding materials with cementitious characteristics gives the final mixture greater resistance and durability, and incorporating an industrial by-product such as ladle furnace slag (of which cementitious characteristics have been corroborated by various authors) enables the creation of sustainable, resistant pavement. This paper describes the incorporation of ladle furnace slag in reclaimed asphalt pavements (RAP) to execute in-place asphalt pavement recycling with bitumen emulsion. Various test groups of samples with increasing percentages of emulsion were created to study both the density of the mixtures obtained, and their dry and post-immersion compressive strength. To determine these characteristics, the physical and chemical properties of the ladle furnace slag and the reclaimed asphalt pavements were analyzed, as well as compatibility with the bitumen emulsion. The aforementioned tests define an optimal combination of RAP (90%), ladle furnace slag (10%), water (2.6%), and emulsion (3.3%), which demonstrated maximum values for compressive strength of the dry and post-immersion bituminous mixture. These tests therefore demonstrate the suitability of ladle furnace slag for cold in-place recycling with bitumen emulsion. [ABSTRACT FROM AUTHOR]

Scarcity of raw materials, reduction of greenhouse gas emissions and reduction of waste disposal in landfills are leading to the development of more sustainable building materials. Based on these lines, this work studies the incorporation of biomass bottom ashes into ceramic materials for brick manufacture, in order to reuse this currently unused waste and reduce clay extraction operations. To this end, different groups of samples were made with different combinations of clay and biomass bottom ashes, from 100% clay to 100% biomass bottom ashes. These samples were shaped, sintered and subjected to the usual physical tests in ceramics. In turn, the mechanical resistance, color and leaching of the contaminating elements present were studied. The physical and mechanical tests showed that the results of all the families were adequate, achieving compressive strengths of over 20 MPa and leaching of the contaminating elements acceptable by the regulations. Therefore, a sustainable range of ceramics was developed, with specific properties (porosity, density, resistance and color), with a waste that is currently unused and sustainable with the environment. [ABSTRACT FROM AUTHOR]