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The recycling of fly ash from municipal solid waste incineration is currently a global issue. This work intends to examine the viability of a novel recycling alternative for fly ashes as a component of fire-resistant plates. To lessen the quantity of heavy metal leaching, the fly ash was utilized after being washed using a water/fly ash ratio of 2 for one hour. Subsequently, an inexpensive, straightforward molding and curing process was used to create a plate, with a composition of 60%wt of MSWI-FA, 30%wt of gypsum, 0.5%wt of glass fiber and 9.5%wt of vermiculite. The plate exhibited high fire resistance. Furthermore, it demonstrated compression, flexural strength and surface hardness slightly lower than the requirements of European Standards. This allows for manufacturing plates with a high washed MSWI-FA content as fire protection in firewalls and doors for homes and commercial buildings. A Life Cycle Assessment was carried out. The case study shows that a 60% substitution of gypsum resulted in an environmental impact reduction of 8–48% for all impact categories examined, except four categories impacts (marine eutrophication, human toxicity (cancer), human non-carcinogenic toxicity and water depletion, where it increased between 2 and 718 times), due to the previous washing of MSWI-FA. When these fly ashes are used as a raw material in fire-resistant materials, they may be recycled and offer environmental advantages over more conventional materials like gypsum

The aim of this study is to compare the mechanical and physical properties of different geopolymer mortars made with granulated blast furnace slag as a geopolymer source material, NaOH (8 M) as the activating solution, and three different types of fine aggregates (air-cooled blast furnace slag, biomass bottom ashes, and silica sand). The samples were made with an aggregate/geopolymer ratio of 3/1, and physical (density and mercury intrusion porosimetry), mechanical (compressive and flexural strength), and acid attack resistance were determined. When air-cooled blast furnace slag is used, the mechanical and acid attack properties are improved compared with silica sand and biomass bottom ashes because of the existence of amorphous phases in this slag, which increase the geopolymer reaction rate despite the particle size being higher than other aggregates. It can be highlighted that the use of ACBFS as a fine aggregate in geopolymer mortars produces better properties than in cement Portland mortar.

In this study is explored the use of construction and demolition waste as fine aggregate in mortars. The addition of nano-graphene oxide (0.1%wt) has also been evaluated. Tests were conducted to determine their density, humidity content, water absorption capacity and open void porosity (using water absorption) and the micro and nano-porosity using Hg intrusion and N2absorption techniques, as well as their flexural and compressive strength and resistance to acid attacks. The mechanical properties of mortars manufactured with standard sand were better (30%) than made with waste aggregate. Mortars with both aggregates can be classified as M20. Nano-Graphene oxide acts as a filler, reducing the volume of macro and micro pores, thereby increasing the mechanical performance, especially when recycled aggregates are used (30% the flexural strength for recycled aggregates and 4% for standard sand). The addition of nano-graphene oxide reduces the transmission channels of acid within mortar., Este estudio explora el uso de residuos de construcción y demolición como árido fino en morteros. Se ha evaluado la adición de nano-óxido de grafeno (0.1%p). Se ha analizado la porosidad abierta usando absorción de agua, micro-porosidad con intrusión de Hg y nano-porosidad por absorción de N2, así como su resistencia a la flexión, compresión y resistencia al ataque ácido. Las propiedades mecánicas con arena estándar fueron mejores (30%) que, con árido reciclado, aunque los dos morteros pueden ser clasificados como M20. El volumen de macro y micro-poros disminuyó con nano-oxido de grafeno, lo que aumentó las propiedades mecánicas, especialmente cuando se utilizan agregados reciclados (30 % de la resistencia a la flexión para áridos reciclados y 4 % para áridos estándar). La adición de nano-oxido grafeno reduce los canales de transmisión de ácido dentro del mortero aumentando la resistencia a compresión tras el ataque ácido.

Ladle slag, a byproduct of steel manufacturing, exhibits inherent reactivity and undergoes hydration when exposed to water. Nevertheless, these reaction byproducts often remain metastable, leading to microstructural alterations when incorporated into cementitious materials, thereby limiting the recycling potential of ladle slag. This study explores the fire insulating capacity and the physical, mechanical, and leaching characteristics of gypsum-based materials with substantial quantities of ladle slag in instead of gypsum. The mechanical strength of the specimens declines as the ladle slag content increases. Nevertheless, the percentage decrease in compressive strength at various temperatures (300 °C, 500 °C, and 700 °C) is less pronounced when higher amounts of ladle slag are used. Fire-resistant properties, assessed using the EN 1363-1 standards, diminish with increasing slag proportions; although the inclusion of ladle slag introduces certain endothermic processes that positively affect the fire insulating capacity, resulting in a 20% reduction when 60%wt of slag is employed. Notably, no gas emissions were observed during the fire test, indicating the absence of environmental hazards. In conclusion, ladle slag does not pose a leaching threat to the environment, making it a viable and sustainable alternative to gypsum in gypsum-based materials.

In this study, biomass ashes from different energy valorization processes and storage conditions were used to make fire-resistant materials. Some of the ashes were subjected to a carbonation process. An 80/20 ash/gypsum ratio was used in all compositions. The density and different mechanical properties (compressive and flexural strength, superficial hardness, and dynamic modulus of elasticity), as well as fire resistance properties (insulating capacity and heat absorption capacity), were evaluated at 28 days. The energy valorization had a great influence on the particle size and the Loss On Ignition (LOI) of the fly ash. By increasing both, materials with lower mechanical properties (90%) were produced. Fire resistance was similar for the different ashes tested, but 50% lower than the gypsum material. When the ashes of the materials were carbonated, the material increases compressive strength by 400% compared to ashes without the carbonation process, and the fire resistance was similar to those materials composed exclusively of gypsum, but also a source of CO₂ capture is produced.

This research analyzes whether a titanium dioxide waste (TiO2 waste) can be used as a source material for geopolymers with good fire resistance properties. Samples with differ ent proportions were prepared, replacing fly ashes with titanium dioxide waste on geopolymers (0, 20, 30, 40 and 100% w/w). The activating solution has a Na2O/SiO2 molar ratio of 0.98. Physical (bulk density, moisture content and water absorption) and mechanical (superficial hardness and compressive strength) characteristics have been evaluated. In addition, their thermal behavior at high temperatures (fire resistance, compressive strength at elevated temperature and absorbed energy) has also been evaluated to see if they can be used as fire insulating materials. This work also studies the radiological activity of geopolymer materials. The replacement of FA with WTiO2 increases the bulk density due to its higher specific bulk density. The highest compressive strength values were obtained with a TiO2 waste content between 30 and 40% w/w. The compressive strength decreases at high temperatures, especially when more TiO2 waste is added. When the amount of TiO2 waste is increased, so is the plateau of evaporation, and this, in turn, increases the resistance to fire. Geopolymers containing FA and TiO2 waste do not present radiological problems, although, when the TiO2 waste is increased, the activity index of the geopolymer also rises.

In this work, the recovery of valuable metals from Bayer red mud using hydrometallurgical techniques and the subsequent use of the solid remaining after leaching as the principal component of the fired bricks were analyzed. Water, sulfuric acid, and sodium hydroxide were used as leaching agents. Different L/S ratios and contact times were also tested. According to technical, economic, and environmental considerations, the optimal conditions to recover valuable elements from red mud were 2 M H2SO4, in contact for 24 h, with an L/S ratio = 5. Under these conditions, high leaching yields of valuable elements such as La (47.6%) or V (11%) were achieved. After the leaching process, the remaining solid was mixed with clay and water to produce bricks. Two doses of red mud (50 and 80% w) and two different sintering temperatures (900 and 1100 °C) were tested. When the proportion of treated RM in the mix was increased, the compressive strength of the bricks was reduced, but it was increased as the sintering temperature was increased. The environmental safety of the bricks manufactured (leaching of heavy metals and radionuclides) was also studied, and it was found that it was more favorable when red mud was treated instead of fresh red mud being used.

Geopolymer manufacturing by means a ready-mix procedure using powder sodium silicate as activator is described in this paper. Its characteristics are compared with conventional geopolymers using aqueous sodium silicate. Degree of reaction, mercury intrusion porosity and compressive strength were measured at different curing times. Three durability tests were carried out. The geopolymer obtained using powder activator showed slightly lower mechanical properties and better durability results than those found for geopolymers based on aqueous activators. In addition, the manufacture of geopolymers based on powder silicate was easier and simpler than the more common procedure using sodium silicate solutions, so the ready-mix manufacturing could be an alternative to produce geopolymers.

En nuestro entorno, todos los objetos que nos rodean están pintados. Desde las paredes de las viviendas, muebles, vehículos, hasta las carreteras que transitamos. Gracias a las pinturas se obtienen efectos estéticos a través de los objetos, además de la protección que éstas confieren a los materiales. Queda por tanto de manifiesto la importancia de la industria de la pintura en nuestras vidas. Un sector importante en el uso de pinturas es el sector de la construcción. Éste además es una de las actividades que más residuos produce, de hecho, los residuos de pintura forman parte de los denominados residuos de construcción y demolición. Otro problema ambiental a añadir, además de la cantidad de residuos que se generan en esta actividad, es el tratamiento que reciben, que en la actualidad no es en muchos casos lo suficientemente apropiado para su aprovechamiento. Este proyecto se plantea con el objetivo último de minimizar el impacto producido por los residuos de pintura, mediante la obtención de nuevos materiales constructivos que los incluyan, materiales que muestren unas propiedades destacadas, al tanto que reducen los efectos negativos de dichos residuos. En resumen, la incorporación de los residuos de pintura en nuevos productos pretende contribuir a orientar la economía hacia un modelo circular. Dichos objetivos se van a conseguir gracias al uso de geopolímeros. Estos materiales han ido evolucionando en las últimas décadas y son muy demandados por las bajas emisiones de CO2 durante su producción. Por lo tanto, en este estudio se pretende comprobar mediante diversos ensayos físicos y mecánicos si los nuevos materiales de construcción creados con geopolímeros y con pintura cumplen o no con las especificaciones de los materiales a los quieren sustituir., In our environment, all the objects that surround us are painted. From the walls of the houses, furniture, vehicles, to the roads we travel. Thanks to the different types of paint, aesthetic effects are obtained through the objects, in addition to the protection they give to the materials. The importance of the painting industry in our lives is therefore evident. An important sector in the use of paint is the construction industry. This is also one of the activities that produces the most waste, in fact, paint waste is part of the so-called construction and demolition waste. Another environmental problem to take into account in addition to the amount of waste generated in this activity is the treatment they receive, which in many cases is not appropriate enough for its use. This project is proposed with the ultimate objective of minimizing the impact produced by paint residues, by obtaining new construction materials that include them, materials that show outstanding properties, while reducing the negative effects of said residues. In summary, the incorporation of paint residues in new products aims to help orient the economy towards a circular model. These objectives will be achieved thanks to the use of geopolymers. These materials have been evolving in recent decades and they are in high demand due to the low CO2 emissions during their production. Therefore, in this study we will pretend to verify through various physical and mechanical tests if the new construction materials created with geopolymers and paint conform or not with the specifications of the material they want to replace.

El principal objetivo de este proyecto es analizar y evaluar las propiedades físicas y mecánicas de geopolímeros dopados con nanopartículas de óxido de grafeno. Se realiza una primera introducción, donde se comentará el origen, las estructuras y los diferentes métodos de síntesis para la obteción del grafeno, óxido de grafeno (GO) y óxido de grafeno reducido. También se mostará a gran escala como es el mercado, hoy en día, a nivel mundial del grafeno y algunas de las empresas dedicadas a este sector en España. En segundo lugar, se especificarán algunas de las aplicaciones del grafeno y óxido de grafeno para la adsorción de metales pesados, la creación de baterías de dispositivos electrónicos de bajo coste de óxido de grafeno y la modificación de las propiedades de pigmento azul. Otra de las aplicaciones discutidas, es la fabricación de supercondensadores debido a su amplia superficie específica, la alta conductividad eléctrica y la estabilidad química, así como las propiedades mecánicas, térmicas y ópticas. Además, se realizará un estudio sobre el efecto del óxido de grafeno modificado con amina orgánica sobre la resistencia al envejecimiento, la pérdida de rodadura y la resistencia al deslizamiento en húmedo de la solución caucho de estireno-butadieno polimerizado. Ante la diversidad de geoplímeros que existen, se hará una introducción sobre los mismos, se describirán las distintas cadenas y mecanismos de la reacción de geopolimerización, las materias primas utilizadas para fabricarlos, sus propiedades y características (física, química, mecánicas y medioambientales) y los campos potenciales de aplicación. Se explicarán las diferentes modificaciones que sufren los geopolímeros al ser dopados con nanopartículas, primeramente, con nanomateriales tales como la nano-sílice o la nano-alúmina y al añadirle el nanocompuesto de óxido de grafeno. Estas modificaciones serán medidas por diversos métodos. Por último, se detallarán algunas de las aplicaciones de los geopolímero, The main objective of this project is to review the state of the art the physical and mechanical property of geopolymers doped with oxide nanoparticles. A first introduction is made, where the origin, structures and different synthesis methods for obtaining graphene, graphene oxide (GO) and reduced graphene oxide will be discussed. It will also be shown on a large scale how is the market, today, worldwide for graphene and some of the companies dedicated to this sector in Spain. Secondly, some of the applications will be specified, such as the use of graphene and graphene oxide for the adsorption of heavy metals, the creation of low-cost electronic device batteries based on graphene oxide and the modification of pigment properties. blue. Another of the applications discussed is the manufacture of supercapacitors due to their wide specific surface, high electrical conductivity and chemical stability, as well as mechanical, thermal and optical properties. And a study on the effect of organic amine modified graphene oxide on aging resistance, rolling loss and wet slip resistance of the polymerized styrene-butadiene rubber solution. Next, given the diversity of geoplimers that exist, an introduction on geopolymerization will be made, fields of potential application, in general the raw materials from which these geopolymers are formed, and specifically the properties of the raw material used in the present bibliographical study. The different chains and mechanisms to obtain geopolymerization will be described and the properties and characteristics of this new material, both physical and chemical, and its applications are summarized. The different modifications that geopolymers undergo when introducing nanotechnology will be explained, firstly, with nanomaterials such as nano-silica or nano-alumina and later when adding the nanocomposite of graphene oxide. These modifications will be analysed using with various methods. Lastly, some of the applications of graphene oxide-do

En los últimos años, la descarga excesiva de fosfato al medio ambiente acuático se ha convertido en el principal problema ambiental que amenaza a todo tipo de organismos vivos. La alta concentración de fosfato en ríos y lagos acelera el crecimiento de plantas y organismos acuosos. Este crecimiento excesivo reduce el oxígeno disuelto y provoca la muerte de organismos acuáticos, y es conocido con el nombre de eutrofización. En consecuencia, se requieren técnicas eficientes para eliminar fosfatos y así evitar la eutrofización en las aguas residuales. Los procesos más utilizados para eliminar fosfatos son los tratamientos biológicos y los tratamientos físicoquímcios, siendo la precipitación química el procedimiento más usado. Pero estos métodos son demasiados caros o no son efectivos para eliminar fosfatos en bajas concentraciones. Sin embargo, los últimos estudios han demostrado que la adsorción, es una de las técnicas de eliminación más eficiente y económica en la eliminación de fosfato debido a su simplicidad y flexibilidad de diseño. La bentonita es un tipo de arcilla, la cual se compone de alúmina y sílice principalmente. Esta ha sido estudiada debido a las buenas propiedades adsorbentes, como consecuencia de su capacidad de intercambio catiónico y su alta superficie específica. Además de dispersarse fácilmente en medio acuoso, lo cual aumenta la eficacia del tratamiento. Debido al alto contenido en sílice y alúmina que presenta la zeolita, se ha querido comparar su capacidad de adsorción con la de la bentonita. Ádemas, la búsqueda actualmente de adsorbentes altamente eficientes, respetuosos con el medio ambiente y rentables, se ha querido comparar también con la geopolímeros basados en subproductos industriales o residuos, ya que estos se consideran similares a la zeolita en su estructura química y mineralógica. Por tanto, se ha llevado a cabo, un estudio bibliográfico de la adsorción de fosfato en aguas residuales a partir de distintos adsorbentes como son la ben, In recent years, the excessive discharge of phosphate into the aquatic environment has become the main environmental problem that threatens all kinds of living organisms. The high concentration of phosphate in rivers and lakes accelerates the growth of plants and aqueous organisms. This overgrowth reduces dissolved oxygen and causes the death of aquatic organisms, this is known as eutrophication. Consequently, efficient techniques are required to avoid eutrophication in wastewater. The most used processes to remove phosphates are biological treatments and physical-chemical treatments, with chemical precipitation being the most widely used procedure. But these methods are too expensive or ineffective at removing phosphate in low concentrations. However, the latest studies have shown that adsorption is one of the most efficient and economical removal techniques in phosphate removal due to its simplicity and design flexibility. Bentonite is a type of clay, which mainly consists of alumina and silica. This has been studied due to the good adsorbing properties, as a consequence of its cation exchange capacity and its high specific surface. In addition to being easily dispersed in an aqueous medium, which increases the effectiveness of the treatment. Due to the high content of silica and alumina, which zeolite present, this has been compare its adsorption capacity with that of bentonite. However, due to the current search for highly efficient, environmentally friendly and cost-effective adsorbents, it has also been comparate with geopolymers based on industrial byproducts or residues, since these are considered similar to zeolite in their chemical and mineralogical structure. Therefore, a bibliographic study of phosphate adsorption in wastewater from different adsorbents such as bentonite, zeolites and geopolymers has been carried out.

El amoniaco es uno de los principales contaminantes del agua y se produce en muchas actividades del ser humano. La eliminación de dicho compuesto de las aguas residuales es compleja, por lo que muchas técnicas se han desarrollado a lo largo del último siglo como la desnitrificación biológica y el stripping con aire. Sin embargo, estas tecnologías presentan la desventaja de ser incapaces de alcanzar bajas concentraciones, afectando así los cuerpos de agua donde se vierten, dañando el ecosistema de la zona. Además, son tecnologías dependientes de temperaturas óptimas y de una gran infraestructura para el realizar dicho tratamiento. Se han investigado nuevas tecnologías para la eliminación de amoniaco. Una de ellas es la oxidación electroquímica del amoniaco. Este proceso es capaz de eliminar el amoniaco de las aguas residuales, alcanzando bajas concentraciones y oxidándolo a nitrógeno gas. El nitrógeno gas es un compuesto inocuo que puede liberarse en la atmosfera, ya que el 79% volumétrico de ella está compuesta por N2. En este trabajo se presenta este último método de desnitrificación, comparando las diferentes formas de llevarlo a cabo y explicando cómo se podría escalar industrialmente. Además, también incluye el efecto que tiene la composición del agua residual en el proceso y cómo se podría adaptar para que la tecnología fuese válida para la misma., Water scarcity is a problem that affects heterogeneously all the world. Ammonia is one of the principal contaminants of water and is produced in many activities of the human being. The removal of ammonia from wastewater is complex, many techniques have been developed through time like biological denitrification and air stripping. However, they present the disadvantages of not being able to reach low concentrations, and are dependent on optimal temperature and big infrastructure to perform the treatment. New technologies for ammonia removal are researched. One of them is the use of electrochemical oxidation of ammonia. This process is capable to remove the ammonia in the wastewater, achieving low concentrations by oxidizing it to dinitrogen. Dinitrogen is an innocuous compound that can be released in the atmosphere since 79% of it is composed of N2. This thesis presents this last method of denitrification, comparing the different ways to perform it and explaining how the industrial scaling could be done. Additionally, it also includes the effect that the wastewater composition has in this process and how it could be adapted to make it valid for this technology.

More and more by-products are being used in certain materials, especially in the construction industry. Natural construction materials contain amounts of heavy metals and radionuclides, but when by-products are used in these kinds of materials, this could lead to a growth in their concentrations and have a negative impact on public health.In this paper, red mud was used as a raw material (as a clay substitute) to manufacture fired bricks. Physical, mechanical, radiological and heavy metal leaching properties of fired bricks with a replacement ratio of up to 80 wt% of clay to red mud are discussed. In addition, the effect of different sintering temperatures (1173K and 1373K) was analyzed, and results showed that the higher the temperature produced, the higher the mechanical strength.To environmentally characterize materials, they were subjected to two different leaching tests: a batch test for raw materials and a monolithic test for the bricks, respectively. The results obtained were compared with the limits stated for several heavy metals by the European Landfill Directive. Results showed that red mud gives leachate concentration values for Cr higher than the limits stated for non-hazardous by-products. Bricks do not exhibit the same problem in the samples containing a high RM proportion and manufactured at a low sintering temperature (1173K), although in the case of V, a high concentration is observed.The contents of radionuclides such as Ra-220, Th-232 and K-40 of the final construction materials were analyzed and compared with different indexes. This paper indicates the maximum amounts of RM that can be used to replace clay for the manufacture of fired bricks without environmental risk.

Este Trabajo de Fin de Grado tiene como objetivo principal hacer un estudio sobre el sector de la minería; sector que es considerado muy importante y en el que estoy dando mis primeros pasos en el mundo laboral. Mi propósito es exponer una comparación sobre los dos métodos distintos de extracción de cobre en las minas de Andalucía, situadas en la Faja Pirítica Ibérica, una concentración de sulfuros masivos que se extiende a lo largo de gran parte del sur de la península ibérica, de Sevilla a Portugal. Un tesoro con 350 años de antigüedad que tiene alrededor de 250 km de largo y de 30 a 50 km de ancho. Más concretamente, este trabajo se centrará en comparar el proceso productivo de Cobre las Cruces, (en adelante CLC), mina en la que trabajo desde julio de 2018. Mi primer contacto con este tipo de industria ha despertado en mí un gran interés, lo que me ha motivado a hacer este trabajo de fin de grado con el fin de adquirir mayor conocimiento sobre el sector, y más en particular sobre la extracción de cobre, ya que ha sido el proceso que más ha llamado mi atención por dos motivos principales: las diferentes maneras de extracción y la cantidad de usos diferentes que tiene y cómo está presente en nuestro día a día. Los minerales de cobre del mundo, y por tanto de la Faja Pirítica ocurren generalmente en depósitos de bajo grado (mineral primario) y requieren concentración antes de la fundición (Pirometalurgia). El método y el grado de concentración dependen de la ubicación de la fundición y programas de producción, junto con la naturaleza del yacimiento. Hay algún caso excepcional en los que se consigue mineral secundario cuya ley es en torno a 4 y 7 grados, este mineral de alto grado requiere un proceso de extracción totalmente distinto. (Hidrometalurgia) Los dos métodos de extracción que se diferencian son Hidrometalurgia y Pirometalurgia. La principal diferencia radica en que con el proceso minero- hidrometalurgico se llega de la mina al metal, lo que llamamos M2M (Mi

En este Trabajo Fin de Grado se realiza una ingeniería conceptual de una planta de valorización energética y eléctrica, con la obtención de biogás, a partir de una corriente final de agua residual procedente de una fábrica de zumos. Se diseña la planta de acuerdo a las características que tiene el agua, dimensionando cada equipo y proceso de la forma más óptima posible desde el punto de vista técnico y económico. De acuerdo con el diseño de la planta, se realiza el balance de materia de cada línea, y se efectúa un análisis económico para ver si es viable el proyecto planteado. Por último, se detalla los aspectos legislativos que existen desde el ámbito autonómico, hasta el europeo., In this Final Degree Project, a conceptual engineering of an energy and electrical recovery plant is carried out, obtaining biogas, from a final stream of wastewater obtained from a juice factory. Design the plant according to the characteristics of the water, sizing each equipment and process in the most optimal way possible from a technical and economic point of view. According to the design of the plant, the balance of the material of each line is made, and an economic analysis is carried out to see if the proposed project is viable. Finally, the legislative aspects that exist from the autonomous area to the European level are detailed.

Según el Banco Mundial, la cantidad de residuos sólidos urbanos está aumentando más rápidamente que la tasa de urbanización como consecuencia del aumento de la población, los patrones de consumo cambiantes, el desarrollo económico, la mejora de los ingresos de los hogares y la creciente urbanización e industrialización. A medida que una sociedad consume más materiales, exige más recursos y genera más contaminantes y desechos. Es por ello por lo que, en las últimas décadas, la Unión Europea ha implementado una amplia gama de legislaciones ambientales y ha desarrollado una serie de objetivos de obligado cumplimiento para los Esta-dos Miembros, con el fin de lograr una economía circular, donde no se desperdicia nada, y respetuosa con el medio ambiente. Este trabajo analiza los datos acerca de la gestión de residuos en Irlanda y España, con el fin de poder pronosticar cuan cerca están ambos países del cumplimiento de dichos objetivos., According to the World Bank, the amount of urban solid waste is increasing faster than the urbanization rate, as a result of population growth, changing consumption patterns, economic development, improved household income and increasing urbanization and industrialization. As a society consumes more materials, it demands more resources and generates more pollutants and waste. That is the reason WHY, in recent decades, the Eu-ropean Union has implemented a wide range of environmental legislation and has developed a series of man-datory objectives for Member States in order to achieve a circular economy, (where it is not wasted nothing, and respectful with the environment.) by wasting nothing and being respectful with the environment. This paper analyzes the waste management data provided by Ireland and Spain, in order to predict how close both countries are to meeting these objectives.

Debido a los problemas asociados al uso de plásticos convencionales, sobre todo aquellos destinados a un solo uso, y a la escasez de las materias primas necesarias para producirlos, en los últimos años diferentes alternativas han sido desarolladas para reemplazarlos. El ácido poliláctico (PLA), un polímero que se obtiene del ácido láctico ha demostrado ser una alternativa eficaz al uso de plásticos convencionales. Este Proyecto desarrolla y describe una planta de producción de PLA con una capacidad de 20 000 toneladas al año. El objetivo principal es obtener un polímero de alto peso molecular adecuado para el procesado de plástico. Para ello, se realiza un estudio de mercado para definir la capacidad de la planta, así como un estudio del polímero para escoger el método de producción adecuado. Además, se adjunta un diagrama del proceso, así como los balances de materia y energía de la planta para especificar los equipos principales y realizar un estudio básico de costes, Due to the problems associated with the use of conventional plastics, mainly those which are disposable, and the shortage in the near future of raw materials required to produce them, in recent years some alternatives have been developed in order to replace them. Polylactic acid (PLA), a polymer based on lactic acid, has proven to be an effective alternative to the use of conventional plastics. This Project aims to develop and describe a basic engineering of a PLA production plant with a capacity of 20 000 tonnes per year. The main goal is to obtain a high molecular weight polymer suitable for plastic processing. For that purpose, a market study is carried out in order to define the capacity of the plant, as well as a study of the polymer in order to choose the appropriate production process. In addition, a PFD is attached, as well as the mass and energy balances of the plant to specify the main equipment and conduct a basic cost study of the plant.

Paval, a solid waste stream from the aluminum industry, is used as a pore generation agent in geopolymers. Paval was mixed with coal combustion fly ash, as a geopolymeric precursor, and activated with alkaline solution with the aim of obtaining porous geopolymers to be used as noise barriers. Both geopolymeric and pore generation reactions happen simultaneously. Aluminum from Paval can react with water and OH from the geopolymerization activating solution, producing hydrogen. The hydrogen gas released generates a highly porous material. The influence of the fly ash-paval proportion and the setting temperature on open porosity, compressive strength and noise-absorbing properties were evaluated. To better understand these influences, the setting time, volume expansion and mineral composition were also studied. The obtained results showed that a higher Paval content (fly ash-Paval ratio 50:50) and setting temperature (70 C) produced a lower setting time and higher volume expansion, increasing the open porosity and improving acoustic properties, but reducing the compressive strength. The material manufactured under these conditions showed similar amorphous phase content to the non-porous geopolymers made without Paval. On the other hand, the obtained materials did not raise environmental concerns in a normalised leaching test.

The depuration of landfill leachate (LL) was evaluated by solar advanced oxidation processes (AOPs) (photo-Fenton + O3 and photo-Fenton + O2) and adsorption processes, using activated carbon made from fish scales, as either post-treatment or pre-treatment of advanced oxidation process. Also, the effect in the reduction of toxicity of LL depurated under these methods was evaluated. The activated carbon Brunauer-Emmett-Teller (BET) surface area is 1.8329 m2/g and the adsorption average pore width is 12.79833 nm, considered as a mesoporous material. When AOPs were used as treatment and adsorption was used as post-treatment of the LL, a removal of 67%, 98%, 98.9%, 83.3% and 99.6% of chemical oxygen demand (COD), colour, copper, iron and ABS254, respectively, was obtained. When the adsorption process was applied as AOP pre-treatment, the removal of organic matter was better in comparison to the results of the adsorption process as AOPs post-treatment. This resulted in a removal of COD, colour, copper, iron and ABS254 of 75.4%, 99.4%, 94.4%, 68.3% and 98.1%, respectively. When the AOPs were followed the adsorption process, a germination index (GI) of 126%, 122% and 116% was obtained. This was higher than the results obtained by LL treated with PF + O2 in a solution concentration of 1%, 3% and 10%, respectively. When PF + O3 was used at a concentration solution of 1%, 3% and 10%, similar GI values were obtained (122%, 113% and 114%, respectively). The EC50 is very low for raw LL, but this value increases as the LL is treated. A very high EC50 is obtained for the adsorption process and for AOPs following the adsorption process, going from 1.8 to 21.0 V/V. Adsorption as pre-treatment helps removing colour and metals from LL, thus enhancing the performance of solar AOPs.

A set of experiments were carried out in order to establish and evaluate the potential of activated carbon, produced from coffee waste in adsorption process, in the depuration of landfill leachate. Different reagents were studied in the activation of carbon: HCl, HCl + H2O2, H3PO4, H3PO4 + H2O2, all with an impregnation rate of 1:1. The activated carbon that showed the best global results was activated with H3PO4, obtaining a 51.0, 32.8, 66.0, 81.0 and 97.1% elimination of chemical oxygen demand, ammonia, total chlorine, bromine and copper, respectively. This activated carbon has a total pore area of 4.85 m2/g and a median pore diameter of 65.32 micrometers. When different loads of this carbon were placed in a stirrer system in contact with landfill leachate, with the aim of evaluating the effect of the adsorption load and contact time, the concentration of ammonia decreased from the beginning of the adsorption process to the end of it, and the removal of ammonia increased with the increase in the adsorbent load. However, the trend of the amount adsorbed per unit mass decreased with increased dosage. The model Freundlich equilibrium isotherm fits experimental data adequately, giving R2 values of 0.95, 1/n of 0.5183, and a K value of 7.08*10-5 L/g, being favourable for adsorption process., Foi realizada uma série de experimentos para estabelecer e avaliar o potencial de carvão ativado produzido de resíduos de café por meio de um processo de adsorção na depuração do lixiviado de aterro sanitário. Foram estudados diferentes reagentes para a ativação do carvão: HCl, HCl + H2O2, H3PO4, H3PO4 + H2O2, todos com taxa de impregnação de 1:1. O carvão que apresentou os melhores resultados foi ativado com H3PO4, obtendo uma eliminação de 51,0; 32,8; 66,0; 81,0; e 97,1% de demanda química de oxigênio e concentração de amônia, cloro total, bromo e cobre, respetivamente. O referido carvão ativado tem uma área total de poro de 4,85 m2/g e diâmetro médio de poro de 65,32 micrômetros. Com o objetivo de avaliar o efeito da carga de adsorção e do tempo de contato, foram colocadas diferentes cargas desse carvão em um sistema de agitação em contato com o lixiviado de aterro sanitário. Observou-se que a concentração de amônia diminuiu e que sua remoção foi maior à medida que a carga adsorvente aumentava. No entanto, a quantidade adsorvida por unidade de massa diminuiu com o aumento da dosagem. Os dados experimentais adequaram-se corretamente ao modelo de isoterma de Freundlich, obtendo-se valores de R2 de 0,95, 1/n de 0,5183, e um valor de K de 7,08*10-5 L/g, considerados favoráveis para o processo de adsorção.

This work evaluates the properties of geopolymer-composites based on blast furnace slag with additions of a carbon fiber waste coming from the aircraft industry. Two parameters were considered: slag/waste ratio (100/0, 80/20 and 60/40) and nature of activating solution (8 M NaOH and sodium silicate). Open porosity and compressive strength were analysed. Geopolymers were also subjected to a sulphuric attack and thermal resistance test (compressive strength after 105, 300, 500 and 700 C was assessed). Porosities increased and compressive strengths decreased as the slag was replaced by the carbon fiber waste. A positive effect of the carbon fiber waste on the acid attack was observed mainly due to the created porosity which could generate space to calcium-sulphate products precipitation. CFW incorporation improved the thermal resistance since higher porosity could provide channel to increase heat dissipation.

This paper focused on the germanium recovery from an Integrated Gasification with Combined Cycle fly ash (IGCC FA). The global process comprised the leaching of the IGCC fly ash with an aqueous solution containing tartaric acid, retention of the germanium-tartaric chelate onto a conventional anionic resin (IRA-900) and elution of germanium. The last step consisted of the germanium precipitation which was accomplished with tannic acid. The leaching experiments were performed with tartaric aqueous solutions and with the raffinate from the subsequent ion-exchange (IX) step. Raffinate from the IX step can be reintroduced in the process as leaching solution. When the contact between FA and leaching solution was maintained for 3 h at pH = 1, the Ge leaching efficiency achieved 86%. The effect of pH, resin dosage and tartaric acid dosage on the Ge retention onto the IRA-900 resin was investigated employing a centered composite rotatable design (CCRD) for experimental design and analysis of results. The retention of Ge-tartaric acid complex onto IRA-900 was optimized using design-expert software and the optimum predicted efficiency and loading capacity were 90–98% and 3.0–3.5 mg·g−1. The experimental affinities that IRA-900 showed for the elements extracted (leached) were: Ge >> Sb > V > Ni > As > Sn > B > Zn. Different eluting solutions were tested, and more than 90% of Ge elution was achieved with 2 M HCl. Final solutions contained Ge, Sb and V. Precipitation tests focused on the optimum pH for Ge precipitation adding tannic acid to the elution solutions. A 99.3% of Ge was precipitated from eluting solution, adding 33.3 g of tannic acid per g of Ge. V also precipitated in some extent along with Ge but the rest of elements practically remained in solution.

In the present study, a waste aluminate solution from the anodizing industry was used to synthesize coal fly ash- and blast furnace slag-based geopolymers as metal-immobilizing matrixes. Different alkali-activating agents such as NaOH and sodium silicate have also been used in order to achieve defined Si/Al or Na/Al ratios in the mixtures. Mixtures of simulated waste containing hazardous metals such as Pb, Cd, or Ni with the geopolymer materials have been processed to study the potential of geopolymers as waste immobilizing agents. The effects of composition on the compressive strength and metals leachability were assessed. Of the two aluminate geopolymers studied, those containing slag exhibited better mechanical performance. Concentrations of the metals leached from the stabilized products were strongly pH dependent, showing that the leachate pH was an important variable for the immobilization of metals.

The aim of this work is the development of a porous geopolymeric foam with sound absorbing properties using silica fume as the pore generation agent. The samples were manufactured using a coal combustion fly ash as source material for the geopolymerization reaction, an alkaline solution as activating solution and silica fume as pore forming agent. Three parameters were studied: silica fume proportion (0, 20 and 40 wt%), activating solution (potassium silicate and potassium hydroxide) and setting temperature (40 and 70 °C). Once the samples were prepared, the experimental study of the most important physical, mechanical and acoustic features were carried out. The increase in the proportion of silica fume in the mixture and setting temperature produced a reduction in setting time and a raise of open void porosity, reducing the compressive strength at 28 days up to a half but increasing the sound absorption. The influence of activating solution in open porosity and sound absorbing properties was not very important.

The main contribution of this paper relates to the development of a systematic study involving a set of parameters which could potentially have an impact on geopolymer properties: curing temperature, type of activating solution, alkali metal in solution, incorporation of slag (Ca source) and type of slag used. The microstructures, degrees of reaction, porosities and compressive strengths of geopolymers have been evaluated. Geopolymers prepared with soluble silicate presented a more compacted and closed structure, a larger amount of gel, lower porosity and greater compressive strength than those prepared with hydroxides. On the other hand, Na-geopolymers were more porous but more resistant than K-geopolymers. Although there is an inverse relation between degree of reaction and porosity, between compressive strength and porosity it is not always inversely proportional and could, in some cases, be masked by changes produced in other influencing parameters., Contribuciones al estudio de la porosidad de geopolímeros basados en cenizas volantes. Relación entre grado de reacción, porosidad y resistencia a compresión. La principal contribución de este documento es el desarrollo de un estudio sistemático implicando una serie de parámetros que podrían afectar a las propiedades de los geopolímeros: temperatura de curado, solución activadora, metal alcalino de la solución, incorporación de escorias (fuente de calcio) y tipo de escorias. Se han evaluado: microestructura, grado de reacción, porosidad y resistencia a compresión. Los geopolímeros preparados con silicatos presentaron un microestructura más densa y compacta, una mayor cantidad del gel geopolimérico, menor porosidad y mejores propiedades mecánicas que los preparados con hidróxidos. Los geopolímeros preparados con sales de sodio fueron más porosos pero más resistentes que los preparados con sales potasio. Aunque existe una relación inversa entre el grado de reacción y la porosidad, en algunos casos, la relación entre resistencia y porosidad es inexistente ya que puede estar enmascarada por cambios producidos por otros parámetros que afecten a la reacción.

This paper presents the results of a study about the effect of fire on geopolymer paste composed of fly ashes, metakaolin and sodium silicate. 2 cm thick, 28 cm high and 18 cm wide panels were filled with the paste obtained. After 28 days of curing at 20 °C and 45% of relative humidity, different tests were carried out in the geopolymers: physico-chemical (density, water absorption, porosity), mechanical (flexural and compressive strength), fire resistance and environmental (leaching and radioactivity). The panels manufactured have been compared with other commercial panels in order to determine the recycling possibilities of fly ashes in manufacturing new fire-insulating geopolymers. The panels obtained can be utilized for the production of interior wall materials, with a good physical, mechanical, fire resistant properties without any environmental problem.

The present investigation aims to analyse alternative uses of bottom ash and fly ash as part of construction materials for different applications: bottom ashbased ceramic bricks, pozzolanic material in the cement production, waste stabilisation/solidification of an electric arc furnace dust using ash-based geopolymers, and ashbased geopolymers used as hydraulic road binders. Different replacements of natural materials by different fly and/or bottom ashes have been studied in all the cases. This study has analysed various parameters influencing the manufacturing process, with the aim of reducing the energy consumption of these processes, as they have been, for example, the firing temperature of bricks and grind size of bottom ashes in cements. All materials are manufactured in a simple and economical way, in order not to increase the cost of the products, and the final products have been evaluated according to different European standards used in these applications, in order to assess their possible, actual technical feasibility. The results obtained in this study show that even higher ratios of replacement ([40 %) of ashes have properties similar to those commonly used.

En la presente tesis se ha realizado un estudio sobre las posibilidades que ofrecen los geopolímeros basados en cenizas volantes procedentes de la combustión de carbón pulverizado en Centrales Térmicas en su aplicación a la Estabilización/Solidificación (E/S) de residuos industriales que contienen metales pesados y otros elementos peligrosos. La aplicación de la tecnología de la geopolimerización a la E/S de residuos peligrosos es relativamente nueva y ha sido promovida por la amplia variedad de propiedades y características favorables de los geopolímeros, entre ellas su alta resistencia mecánica, resistencia a los ácidos, alta integridad estructural y baja permeabilidad. La primera parte de esta tesis ha ido dirigida a la preparación de geopolímeros usando distintas cenizas volantes. Las cenizas volantes de combustión son unos materiales frecuentemente utilizados como elemento precursor en la síntesis de geopolímeros, ya que poseen propiedades y características similares a las de los aluminosilicatos naturales y tienen buenas propiedades puzolánicas y de reactividad. Las principales cenizas usadas en esta tesis proceden, una de la combustión de carbón pulverizado en la Central Térmica de Los Barrios (Cádiz), y la otra de la Central Térmica de Compostilla (León), en la que el combustible utilizado ha sido carbón y coque de petróleo. Además, se han usado otros componentes activos tales como escorias de alto horno y otras escorias metalúrgicas, para favorecer la reacción de geopolímerización. Como soluciones activadoras se han utilizado silicatos sódico o potásico e hidróxidos sódico o potásico, solos o combinando cada silicato con su respectivo hidróxido. Los geopolímeros se han curado al ambiente en el laboratorio o en horno a 60 ºC. A todos los geopolímeros se les ha medido la resistencia a compresión, la porosidad, el grado de reacción y se les ha realizado un estudio microestructural mediante microscopía de barrido electrónico. En la segunda parte de la tesis se

Biomass gasification technology offers an attractive way to use low-grade fuels in energy production with high efficiency and low environmental impact. However, an issue calling for further development is the volume and quality of fly ash, since biomass gasification fly ash contains more un-reacted carbon compounds than fly ash from direct combustion of similar fuels. This restricts direct gasification ash utilisation for many applications and makes some pre-treatment necessary, representing a significant share of the overall operating cost of gasification-based systems for energy production. Therefore, economical methods for the management of this type of ash without any pre-treatment are attractive. In this paper, we present an initial study on the manufacture of bricks made of gasification ash. Our goal was to come up with a product which satisfies two basic requirements: (a) it has elevated percentages of fly ash; and (b) it enables utilisation of ash without any pre-treatment. We have manufactured bricks by means of conventional moulding and curing methods, using ash percentages of up to 20 wt.%. No special additives were added to provide the bricks with acceptable mechanical and/or insulating properties. The fly ash used was generated in a fluidised bed pilot plant for processing olive mill cake, a by-product of the olive oil industry produced in large quantities in several EU countries. Some mechanical and environmental properties of ash gasification bricks were studied and compared with typical values for commercial bricks. The results lead us to conclude that the bricks could be used commercially as low density clay masonry units with a good thermal insulating capacity and, therefore, the potential for commercial development is promising. In addition, the environmental benefit of waste gasification added to the ash utilisation makes the overall process more attractive.

Las capacidades pedagógicas representan una de las partes fundamentales para el desarrollo profesional del novel. El principal objetivo del trabajo era desarrollar el conocimiento pedagógico para mejorar la calidad de la enseñanza y e desarrollo del profesor. Este aspecto es particu­ larmente evidente en ingeniería, por lo que se ha llevado a cabo un estudio en algunas disciplinas relacionadas con la Ingeniería Química y Ambiental. En primer lugar, se hizo una valoración de la situación inicial. Esta revisión se dividió en dos partes. La primera definía el problema general, la segunda analizada los problemas específicos de cada asignatura. Se han realizado diversas actividades para evaluar el aspecto dual de la enseñanza de la ingeniería, es decir, la enseñanza en sí misma (aprender a enseñar) y la química (aprender química para enseñar): sesiones formativas, distintos tipos de reuniones, tests de conocimiento previo, ejercicios prácticos, grabaciones y, finalmente, un test sobre la calidad de la enseñanza realizado por los alumnos., Pedagogical skills represent one of the fundamental parts of a beginner professio­ nal development. This issue is particularly apparent in engineering, subsequently a study has been undertaken in several subjects related specifically to the Chemical and Environmental Engineering. The main aim of the work was to develop the pedagogical knowledge in order to improve the quality of the teaching and teacher development. Firstly, an assessment of the initial situation was completed. This review was divided in two parts. The first defines the general problem, the second analyses specific problems in each subjects. Several activities have been performed to asses the dual aspect of engineering teaching, namely teaching (learning to teach) and chemistry (learning chemistry for teaching): formative sessions, different kinds of meetings, previous knowledge tests, practical exercises, recordings, and finally, one test about the teaching quality that the students have made.