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Tesi en modalitat de compendi de publicacions, (English) Due to the fact that construction, maintenance, and operation of buildings consume almost 40% of global energy today, architects play a major role in the reduction of world energy consumption. Building’s façades can have a significant and measurable impact on the economic, environmental, and social performances by edifices, and their retrofit is seen as a key solution to the problem of today’s aging building stock. Concerning overheating and the potential loss of internal heat, transparent parts of the building façade have a large effect on the building’s energy consumption. Within this context, the use of intelligent systems on architecture envelopes can fulfill contemporary demands as promising solutions regarding energy efficiency, emissions, or the degree of visual contact in building environments. In Spain, boom periods of construction combined with typical building styles of each period, have resulted in a large stock of aging educational buildings at risk of structural vacancy and obsolescence. Despite their lack of insulation, high air infiltration, and solar gain, many such edifices from the 1970s-1980s are still in use today. Moreover, the majority of today's buildings will still be in use in 2050 based on the Spanish edifices' annual replacement rate of 3% according to the European Commission. The main objective of this Ph.D. thesis is to analyze, develop and promote intelligent services to existing façades to optimize these buildings' economic, environmental, and social sustainability performances through a holistic and innovative sustainability assessment model. To do so, the first phases of this thesis, the author carried out a deep documental investigation on more than 800 research articles regarding intelligent façade systems, advancements in material engineering, user demands, automations, and their sustainability performance following the preferred reporting items for systematic reviews and meta-analyses reporting standards. Based on the, (Català) La construcció, el manteniment i funcionament de edificis consumeixen quasi el 40% de l'energia actual, així que els arquitectes tenen un paper fonamental en la reducció del consum energètic. Les façanes poden tenir un impacte significatiu i mesurable en el rendiment econòmic, mediambiental i social dels edificis, i la rehabilitació es considera una solució clau per al problema de l'envelliment del parc immobiliari actual. Pel que fa al sobreescalfament i possible pèrdua de calor interna, les parts transparents de les façanes tenen un gran efecte en el consum energètic de l'edifici. Així, es poden satisfer les demandes actuals amb l'ús de sistemes intel·ligents a envolupants arquitectòniques, com ara solucions prometedores en eficiència energètica, emissions o grau de contacte visual en entorns construïts. A Espanya, els períodes d'apogeu de la construcció han donat lloc a nombrosos edificis educatius envellits que corren el risc de quedar obsolets. Tot i la manca d'aïllament, problemes d'infiltracions d'aire i guany solar, molts d'aquests edificis dels anys 70-80 segueixen en ús avui dia. A més a més, la majoria d'aquests edificis continuaran en ús el 2050, si es té en compte que la taxa de substitució anual dels edificis espanyols és del 3%, segons la Comissió Europea. “L'objectiu principal d'aquesta tesi doctoral és analitzar, desenvolupar i promoure serveis intel·ligents per a façanes existents per optimitzar les prestacions de sostenibilitat econòmica, mediambiental i social dels seus edificis mitjançant un model holístic i innovador d'avaluació de la sostenibilitat”. Per això, les primeres fases d'aquesta tesi, van investigar en profunditat més de 800 articles científics sobre sistemes de façanes intel·ligents, avenços en l'enginyeria de materials, demandes dels usuaris, automatitzacions i el seu rendiment global en matèria de sostenibilitat, seguint els ítems preferits per a la presentació d'informes de revisions sistemàtiques i metaanàlisi. Consider, Postprint (published version)

Efficient waste management, especially in relation to swaste reuse, has become a pressing societal issue. The waste bittern generated during salt production and discarded oyster shells present formidable environmental challenges and a waste of resources for some coastal regions. Therefore, this work developed a two-stage circular process for the environmentally friendly and efficient utilization of both waste materials. In the first stage, CO2 gas and an organic extraction phase comprising Tri(octyl-decyl)amine (R3N) and isoamyl alcohol were introduced into the waste bittern to obtain MgCO3·3H2O (s). The second stage involved reacting the reacted organic extraction phase with oyster shell powders to produce CaCl2·2H2O (s) and CO2 (g) and regenerate R3N. This work focused on investigating the yield of MgCO3·3H2O and the regeneration ratio of R3N, which are crucial indicators for the two stages involved in the process. The results indicate that, under optimal operating conditions, a maximum yield of 87% for MgCO3·3H2O was achieved, and the regeneration ratio of R3N reached 97%. Furthermore, the reaction mechanism and thermodynamic functions of the R3N regeneration process were elucidated as a crucial element in achieving a circular process. The findings of this work offer a sustainable solution to environmental pollution from waste bittern and oyster shells, and provide a promising avenue for green chemical production.

Saffron spices are composed of dehydrated stigmas of Crocus sativus L. A large amount of bio-residues (stamens, tepals, and stigmas) is generated during the production of this spice (~92 g of bio-residues per 100 g of flowers). These bio-residues are usually discarded losing the chance to obtain interesting bioactive compounds from them. In this work, we use the saffron bio-residues as possible source of natural bioactive compounds. Different extraction conditions were applied obtaining hydrophilic and lipophilic components. The antioxidant activity of the bioactive compounds in the different conditions were analysed using the ABTS method developed by our team. Furthermore, the total content of phenolic compounds and flavonoids present in the bio-residues were estimated. We demonstrated that bio-residues contain a high amount of both phenolic and flavonoid compounds with a strong antioxidant potential effect. Moreover, we compared the antioxidant activities of saffron bio-residues (obtained from stamens, tepals, and stigmas). The extraction was made at two different pH (4.5 and 7.5) and measured (antioxidant activity, flavonoid and phenol content) at pH 7.5. Another extraction done at pH 7.5 measured antioxidant activity, flavonoid and phenol content at time 0 (t = 0 h) and after 24 h (t = 24 h) at pH 4.5 and 7.5. We point out that bioresidues contain antioxidant activity (up to 8.42 µmoles Trolox/100 g DW), total phenols (up to 111.91 µmoles EG/100 g DW) and total flavonoids (up to 109.25 µmoles QE/100 g DW) as bioactive compounds. The applicability of bio-residues as additives is promising, both in the pharmaceutical and in the food industry as nutraceuticals and phytogenics. The variability in pH and the colour originating from it must be taken into account.

Marble waste, in the form of sludge obtained from the marble cutting industry, was incorporated in the mixture formulations of concrete block. The possibility of using Waste marble powders (WMP) as a substitute for limestone was investigated over a three-year period. The production of cement block from sludge was standardized in terms of process and content. Interpretation of the results have shown that appropriate incorporation of WMP can result in favorable characteristics in terms of compression strength 6-7 N/nm2 at 28 days, and water absorption (7%), anticipating a complimentary usage of sludge as a by-product instead of being waste.

Marble waste, in the form of sludge obtained from the marble cutting industry, was incorporated in the mixture formulations of concrete block. The possibility of using Waste marble powders (WMP) as a substitute for limestone was investigated over a three-year period. The production of cement block from sludge was standardized in terms of process and content. Interpretation of the results have shown that appropriate incorporation of WMP can result in favorable characteristics in terms of compression strength 6-7 N/nm2 at 28 days, and water absorption (7%), anticipating a complimentary usage of sludge as a by-product instead of being waste.

Marble waste, in the form of sludge obtained from the marble cutting industry, was incorporated in the mixture formulations of concrete block. The possibility of using Waste marble powders (WMP) as a substitute for limestone was investigated over a three-year period. The production of cement block from sludge was standardized in terms of process and content. Interpretation of the results have shown that appropriate incorporation of WMP can result in favorable characteristics in terms of compression strength 6-7 N/nm2 at 28 days, and water absorption (7%), anticipating a complimentary usage of sludge as a by-product instead of being waste.

Marble waste, in the form of sludge obtained from the marble cutting industry, was incorporated in the mixture formulations of concrete block. The possibility of using Waste marble powders (WMP) as a substitute for limestone was investigated over a three-year period. The production of cement block from sludge was standardized in terms of process and content. Interpretation of the results have shown that appropriate incorporation of WMP can result in favorable characteristics in terms of compression strength 6-7 N/nm2 at 28 days, and water absorption (7%), anticipating a complimentary usage of sludge as a by-product instead of being waste.

As coal combustion in thermal power plants generates huge amounts of waste such as bottom ash and fly ash, there is a need to find new applications for these materials. One of the ways of its reuse is chemical or thermal modification of the ash in order to obtain new materials, which can be further used as adsorbents of various pollutants from water. The subject of this research was the alkali modification and alkali activation of fly ash in purpose to increase the adsorption capacity towards heavy metal ions. The success of modification process and characterization of the obtained materials was monitored by Fourier transform infrared spectroscopy, X-ray fluorescence spectroscopy and scanning electron microscopy. The concentration of zinc and cadmium ions after adsorption was determinated by atomic absorption spectroscopy. The kinetics of the adsorption process on the most efficient adsorbent were examined and the experimental data were compared with pseudo-first and pseudo-second order models. The achieved results show a positive effect of alkaline modification of fly ash on adsorption efficiency of both metals, while alkaline activation gives an exceptionally effective adsorbent in the case of zinc.

Marble waste, in the form of sludge obtained from the marble cutting industry, was incorporated in the mixture formulations of concrete block. The possibility of using Waste marble powders (WMP) as a substitute for limestone was investigated over a three-year period. The production of cement block from sludge was standardized in terms of process and content. Interpretation of the results have shown that appropriate incorporation of WMP can result in favorable characteristics in terms of compression strength 6-7 N/nm2 at 28 days, and water absorption (7%), anticipating a complimentary usage of sludge as a by-product instead of being waste.

La industria de la acuicultura se está expandiendo debido a la demanda de alimentos por el crecimiento de la población. En 2019, en España, la producción alcanzó 342.867 toneladas y un valor de primera venta de 501 millones de euros (APROMAR 2020). Las principales especies producidas fueron los mejillones (77%), la lubina (8%) y la dorada (4%), todas especies cultivadas en zonas costeras. Las principales estructuras donde se cultivaban estas especies son bateas y long lines para mejillones (4.793 instalaciones) y jaulas flotantes para lubina y dorada (43 instalaciones) (APROMAR 2020). Ambos cultivos producen enriquecimiento por MO y acumulación de restos de valva de mejillón en los sedimentos marinos. Sin embargo, existe una falta de conocimiento para poder entender todas las consecuencias ecológicas de la interacción entre el enriquecimiento por MO y la acumulación de valvas de mejillón en los ecosistemas bentónicos, ya que aunque se ha estudiado en profundidad el efecto del enriquecimiento por MO sobre los sedimentos (Holmer et al. 2005a; Apostolaki et al. 2007; Holmer et al. 2007), los efectos de acumulación los restos de valva de mejillón en los ecosistemas de sedimentos apenas se han investigado (Newell 2004; Wilding 2012; Wilding and Nickell 2013). Por lo tanto, para mejorar el conocimiento de los impactos de la acuicultura y sus interacciones en los sedimentos, los objetivos generales de la presente tesis doctoral han sido: Capítulo 2) Analizar el efecto de la bioturbación en la capacidad metabólica de los sedimentos a lo largo de un gradiente de enriquecimiento por MO derivado de la acuicultura marina. Capítulo 3) Investigar la interacción entre el enriquecimiento por valva de mejillón y por MO derivado de la acuicultura en flujos biogeoquímicos de sedimentos marinos. Capítulo 4) Comprobar el efecto del enriquecimiento por valva de mejillón y por MO procedente de la acuicultura en la capacidad de bioturbación de la comunidad de la macrofauna de los sedimento

La industria de la acuicultura se está expandiendo debido a la demanda de alimentos por el crecimiento de la población. En 2019, en España, la producción alcanzó 342.867 toneladas y un valor de primera venta de 501 millones de euros (APROMAR 2020). Las principales especies producidas fueron los mejillones (77%), la lubina (8%) y la dorada (4%), todas especies cultivadas en zonas costeras. Las principales estructuras donde se cultivaban estas especies son bateas y long lines para mejillones (4.793 instalaciones) y jaulas flotantes para lubina y dorada (43 instalaciones) (APROMAR 2020). Ambos cultivos producen enriquecimiento por MO y acumulación de restos de valva de mejillón en los sedimentos marinos. Sin embargo, existe una falta de conocimiento para poder entender todas las consecuencias ecológicas de la interacción entre el enriquecimiento por MO y la acumulación de valvas de mejillón en los ecosistemas bentónicos, ya que aunque se ha estudiado en profundidad el efecto del enriquecimiento por MO sobre los sedimentos (Holmer et al. 2005a; Apostolaki et al. 2007; Holmer et al. 2007), los efectos de acumulación los restos de valva de mejillón en los ecosistemas de sedimentos apenas se han investigado (Newell 2004; Wilding 2012; Wilding and Nickell 2013). Por lo tanto, para mejorar el conocimiento de los impactos de la acuicultura y sus interacciones en los sedimentos, los objetivos generales de la presente tesis doctoral han sido: Capítulo 2) Analizar el efecto de la bioturbación en la capacidad metabólica de los sedimentos a lo largo de un gradiente de enriquecimiento por MO derivado de la acuicultura marina. Capítulo 3) Investigar la interacción entre el enriquecimiento por valva de mejillón y por MO derivado de la acuicultura en flujos biogeoquímicos de sedimentos marinos. Capítulo 4) Comprobar el efecto del enriquecimiento por valva de mejillón y por MO procedente de la acuicultura en la capacidad de bioturbación de la comunidad de la macrofauna de los sedimento

Actualment entenem la importància de la preservació de recursos naturals, de la reducció de la contaminació de l'aire, terra i aigua, de l'estalvi energètic, etc. Però el com aconseguir aquests objectius, és un dubte essencial. Aquest projecte creu en el canvi cap a la circularitat dels materials com a solució cap a la sostenibilitat. Mostra els beneficis de la reutilització de residus, sota el lema de "no és brossa". Els objectius principals del treball són el disseny d'un sistema de reutilització de residus amb la intenció de conscienciar als infants, i a les famílies en un segon pla, creant nous hàbits i millorant l'eficiència ecològica del centre educatiu. Per al desenvolupament del treball s'ha seguit la metodologia Design Thinking, per tal de fer una primera fase d'investigació dels usuaris i la relació entre les escoles i els seus residus. Després de la recerca i de representar de manera visual la investigació de l'usuari a través d'eines pròpies del disseny centrat en l'usuari, comença la fase de ideació i creació tenint en compte els resultats de la fase d’indagació. La proposta final es plasma en forma de quatre tallers per a infants de primària, que fan visible les possibilitats dels residus que generem., Now a days we can understand the importance of preserving natural resources, reducing air, land and water pollution, energy saving, etc. But how, it is an essential doubt. This project believes in the shift towards the circularity of materials as a solution to sustainability. It aims to show the benefits of waste reuse, under the slogan 'It is not trash. The main aims of the work are the design of a waste re-use system with the aim of raising awareness among children, and families in the background, creating new habits and improving the ecological efficiency of the educational center. The Design Thinking methodology has been followed for the development of work, in order to make an early phase of user research and the relationship between schools and their waste. After research and trying to visually represent the user's research through user-centered design tools, the design phase begins with the above observations. The final proposal is in the form of four workshops for primary children, which aims to make the possibilities of the waste we generate visible., Actualmente entendemos la importancia de la preservación de recursos naturales, de la reducción de la contaminación y del ahorro energético. Pero como alcanzar estos objetivos, es una duda esencial. Este proyecto cree en el cambio hacia la circularidad de los materiales como solución cercana a la sostenibilidad. Muestra los beneficios de la reutilización de residuos, bajo el lema de "no es basura". Los objetivos principales del trabajo son el diseño de un sistema de reutilización de residuos con la intención de concienciar a los niños, y a las familias en un segundo plano, creando nuevos hábitos y mejorando la eficiencia ecológica de los centros educativos. Para el desarrollo del trabajo se ha seguido la metodología Design Thinking, haciendo una primera fase de investigación de los usuarios y la relación entre las escuelas y sus residuos. Después del estudio y de representar de manera visual la investigación del usuario a través de herramientas propias del diseño centrado en el usuario, empieza la fase de ideación y creación teniendo en cuenta los resultados de la fase de indagación. La propuesta final se plasma en un formato de cuatro talleres para niños de primaria, que hacen visible las posibilidades de los residuos que generamos., Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables::12.8 - Per a 2030, assegurar que les persones de tot el món tinguin informació i conscienciació pertinents per al desenvolupament i els estils de vida sostenibles, en harmonia amb la natura

[EN] Alkali-activated cements are widely studied as alternative and sustainable binder in soil stabilization. In this research work, a mold was designed and constructed, which allowed small cubic specimens to be made (40 x 40 x 40 mm(3)). With the newly designed mold, cubic samples of soil stabilized with portland cement (OPC) and alternative AAC (based on spent fluid catalytic cracking catalyst FCC) were prepared from which compressive strength was obtained. Cylindrical specimens were also prepared using the same binders as in the previous case to obtain their compressive strength. The results obtained in both cases were compared. Greater resistances for cubic samples were achieved. The cubic specimens were selected for being better in terms of standard deviation of compressive strength for AAC stabilized soil. The obtained compressive strength and standard deviation results were compared between the soil specimens stabilized with different stabilizers cured at 7, 14, 28, and 90 days. The method allows small-sized cubic specimens to be prepared. It improves ergonomics. It also facilitates a large number of specimens being obtained with a small amount of sample. Soil stabilized with AAC yielded higher compressive strength after 90 days compared to that with OPC.

Nowadays, the original image and structure of the territory havebeen permanently changed, by human action, due to the intenseindustrialization. The quarries represent the industrial activity that causes more transmutations in the landscape, modifying it in a more invasive manner. The present research describes a case study in Portugal where is located the highest concentration of marble quarries, flanked by escombreiras, large waste heaps. The work highlights the importance of the waste reuse concept in landscape and architecture, preserving the industrial memory and the identity of the place. The research, through an exhaustive analysis of real examples of quarries rehabilitation, investigates innovative methods to regenerate the Portuguese abandoned landscape. The investigationis expected to prompt the implementation of projects to revitalize the discarded spaces, and toreuse the local waste material for the creation, in situ, of architectonic and landscape elements, and to increase the knowledge on waste reuse procedures., Peer Reviewed

Keratin extracted from wool fibers has recently gained attention as an abundant source of renewable, biocompatible material for tissue engineering and drug delivery applications. However, keratin extraction and processing generally require a copious use of chemicals, not only bearing consequences for the environment but also possibly compromising the envisioned biological outcome. In this study, we present, for the first time, keratin-PVP biocomposite fibers obtained via an all-water co-electrospinning process and explored their properties modulation as a result of different thermal crosslinking treatments. The protein-based fibers featured homogenous morphologies and average diameters in the range of 170–290 nm. The thermomechanical stability and response to a wet environment can be tuned by acting on the curing time; this can be achieved without affecting the 3D fibrous network nor the intrinsic hydrophilic behavior of the material. More interestingly, our protein-based membranes treated at 170 °C for 18 h successfully sustained the attachment and growth of primary human dermal fibroblasts, a cellular model which can recapitulate more faithfully the physiological human tissue conditions. Our proposed approach can be viewed as pivotal in designing tunable protein-based scaffolds for the next generation of skin tissue growth devices.

Nowadays, the original image and structure of the territory have been permanently changed, by human action, due to the intense industrialization. The quarries represent the industrial activity that causes more transmutations in the landscape, modifying it in a more invasive manner. The present research describes a case study in Portugal where is located the highest concentration of marble quarries, flanked by escombreiras, large waste heaps. The work highlights the importance of the waste reuse concept in landscape and architecture, preserving the industrial memory and the identity of the place. The research, through an exhaustive analysis of real examples of quarries rehabilitation, investigates innovative methods to regenerate the Portuguese abandoned landscape. The investigation is expected to prompt the implementation of projects to revitalize the discarded spaces, and to reuse the local waste material for the creation, in situ, of architectonic and landscape elements, and to increase the knowledge on waste reuse procedures., Peer Reviewed

The reuse of digested sludge from wastewater treatment plants (WWTPs) as soil fertilizer poses a risk for contamination of soil and water environments. The present study provides a new approach for investigating the exposure of hydrophobic organic chemicals in sewage sludge. The methodology of equilibrium sampling with multiple thicknesses of silicone was successfully validated and applied to complex sludge matrices. Polycyclic aromatic hydrocarbon (PAH) concentrations in silicone (Csilicone) were determined and compared across four WWTPs. Activity ratios (ARs), defined as Csilicone at equilibrium with digested sludge (final product) over Csilicone at equilibrium with secondary sludge (intermediate product), were in the range 0.85–20 with all except one AR>1. These ARs thus revealed increased thermodynamic potential of both parent and alkylated PAHs in digested sludge compared with secondary sludge, and thereby higher exposure of PAHs in sludge after digestion than before digestion. This observation can be explained by the concept of “solvent depletion” as organic matter decreased by a factor of 1.3 during digestion, resulting in reduced sorptive capacity and increased freely dissolved concentrations (Cfree). The PAHs with logKow > 6 had ARs close to 1.3, whereas PAHs with logKow < 6 showed higher ARs than the organic matter decrease factor of 1.3. Cfree in digested sludge were higher than reported in rural soil and generally consistent with levels reported for Baltic Sea sediment.

The reuse of digested sludge from wastewater treatment plants (WWTPs) as soil fertilizer poses a risk for contamination of soil and water environments. The present study provides a new approach for investigating the exposure of hydrophobic organic chemicals in sewage sludge. The methodology of equilibrium sampling with multiple thicknesses of silicone was successfully validated and applied to complex sludge matrices. Polycyclic aromatic hydrocarbon (PAH) concentrations in silicone (Csilicone) were determined and compared across four WWTPs. Activity ratios (ARs), defined as Csilicone at equilibrium with digested sludge (final product) over Csilicone at equilibrium with secondary sludge (intermediate product), were in the range 0.85-20 with all except one AR>1. These ARs thus revealed increased thermodynamic potential of both parent and alkylated PAHs in digested sludge compared with secondary sludge, and thereby higher exposure of PAHs in sludge after digestion than before digestion. This observation can be explained by the concept of "solvent depletion" as organic matter decreased by a factor of 1.3 during digestion, resulting in reduced sorptive capacity and increased freely dissolved concentrations (Cfree). The PAHs with logKow > 6 had ARs close to 1.3, whereas PAHs with logKow <6 showed higher ARs than the organic matter decrease factor of 1.3. Cfree in digested sludge were higher than reported in rural soil and generally consistent with levels reported for Baltic Sea sediment.

We studied the possibility of converting waste toilet paper (WTP) into electricity. WTP is a waste stream with continuous availability and negative cost, but it is difficult to handle, as it contains fecal matter. The process we explored had two stages: WTP gasification followed by direct conversion into electricity in a high-temperature solid-oxide fuel cell (SOFC). The process was studied on a 10 ktpa scale by using real-life parameter values obtained from industrial sources. We presented the basic system design, as well as its electricity yield and overall efficiency on the basis of detailed mass- and energy-balance calculations. By explorative technoeconomic analysis and sensitivity analysis, we found an electric efficiency of 57 %, which is similar to that of a natural gas combined cycle plant. The levelized cost of electricity (LCOE) was 20.3 ¢ kWh−1, which is comparable at present to that of residential photovoltaic installations. The system's capital costs are relatively high, mainly as a result of SOFC investment costs, but we expect these costs to decrease as the market of cells develops. The operating costs are relatively low, partly thanks to the high thermodynamic efficiency (≈70 %). Currently, the fuel costs are negative (because we use waste as a raw material), yet this could change if the value of WTP would increase as a result of this process. Learning effects could make the system more competitive in the future with an LCOE of approximately 11 ¢ kWh−1.

We studied the possibility of converting waste toilet paper (WTP) into electricity. WTP is a waste stream with continuous availability and negative cost, but it is difficult to handle, as it contains fecal matter. The process we explored had two stages: WTP gasification followed by direct conversion into electricity in a high-temperature solid-oxide fuel cell (SOFC). The process was studied on a 10 ktpa scale by using real-life parameter values obtained from industrial sources. We presented the basic system design, as well as its electricity yield and overall efficiency on the basis of detailed mass- and energy-balance calculations. By explorative technoeconomic analysis and sensitivity analysis, we found an electric efficiency of 57 %, which is similar to that of a natural gas combined cycle plant. The levelized cost of electricity (LCOE) was 20.3 ¢ kWh−1, which is comparable at present to that of residential photovoltaic installations. The system's capital costs are relatively high, mainly as a result of SOFC investment costs, but we expect these costs to decrease as the market of cells develops. The operating costs are relatively low, partly thanks to the high thermodynamic efficiency (≈70 %). Currently, the fuel costs are negative (because we use waste as a raw material), yet this could change if the value of WTP would increase as a result of this process. Learning effects could make the system more competitive in the future with an LCOE of approximately 11 ¢ kWh−1., Energy & Industry

1. Organic pollution is widespread in coastal areas and can have profound impacts on the seabed. Coastal sediments play an important role at a global scale in the recycling of organic matter, and this process is influenced by the habitat complexity of the sediments, among other factors. Mollusc shells are produced as a waste product from a range of anthropogenic activities, but we demonstrate that they can be used to increase the habitat complexity of sediments. 2. We studied the effect of mussel-shell debris (shell-hash) on the biogeochemical processes of marine sediments affected by organic pollution, using a mesocosm experiment simulating the bioturbation effects of macrofauna. 3. We found that shell-hash improved the ecological status of organically polluted sediments by reducing the accumulation of sulphide from anaerobic metabolic pathways. 4. Additionally, when shell-hash was present in an organically polluted sediment, there was a decrease in ammonium release to the water column, thus preventing the negative ecological consequences of eutrophication. 5. Synthesis and applications. Our study indicates that shell-hash debris can be used as a potential tool to mitigate the effects of organic enrichment on marine sediments. A density of shell-hash debris of 1900 g m-2 in the sediment can diminish toxic by-products (sulphides and ammonium) derived from the stimulation of anaerobic metabolic pathways by organic pollution, at levels that are biologically relevant. The mitigation effect of shell-hash is more pronounced in sediments where macrofauna is not present.

1. Organic pollution is widespread in coastal areas and can have profound impacts on the seabed. Coastal sediments play an important role at a global scale in the recycling of organic matter, and this process is influenced by the habitat complexity of the sediments, among other factors. Mollusc shells are produced as a waste product from a range of anthropogenic activities, but we demonstrate that they can be used to increase the habitat complexity of sediments. 2. We studied the effect of mussel-shell debris (shell-hash) on the biogeochemical processes of marine sediments affected by organic pollution, using a mesocosm experiment simulating the bioturbation effects of macrofauna. 3. We found that shell-hash improved the ecological status of organically polluted sediments by reducing the accumulation of sulphide from anaerobic metabolic pathways. 4. Additionally, when shell-hash was present in an organically polluted sediment, there was a decrease in ammonium release to the water column, thus preventing the negative ecological consequences of eutrophication. 5. Synthesis and applications. Our study indicates that shell-hash debris can be used as a potential tool to mitigate the effects of organic enrichment on marine sediments. A density of shell-hash debris of 1900 g m-2 in the sediment can diminish toxic by-products (sulphides and ammonium) derived from the stimulation of anaerobic metabolic pathways by organic pollution, at levels that are biologically relevant. The mitigation effect of shell-hash is more pronounced in sediments where macrofauna is not present.

We studied the possibility of converting waste toilet paper (WTP) into electricity. WTP is a waste stream with continuous availability and negative cost, but it is difficult to handle, as it contains fecal matter. The process we explored had two stages: WTP gasification followed by direct conversion into electricity in a high-temperature solid-oxide fuel cell (SOFC). The process was studied on a 10 ktpa scale by using real-life parameter values obtained from industrial sources. We presented the basic system design, as well as its electricity yield and overall efficiency on the basis of detailed mass- and energy-balance calculations. By explorative technoeconomic analysis and sensitivity analysis, we found an electric efficiency of 57 %, which is similar to that of a natural gas combined cycle plant. The levelized cost of electricity (LCOE) was 20.3 ¢ kWh−1, which is comparable at present to that of residential photovoltaic installations. The system's capital costs are relatively high, mainly as a result of SOFC investment costs, but we expect these costs to decrease as the market of cells develops. The operating costs are relatively low, partly thanks to the high thermodynamic efficiency (≈70 %). Currently, the fuel costs are negative (because we use waste as a raw material), yet this could change if the value of WTP would increase as a result of this process. Learning effects could make the system more competitive in the future with an LCOE of approximately 11 ¢ kWh−1., Energie and Industrie

To-date, sanitation has mainly been approached from a public and environmental health perspective and this implies that excreta and other organic waste streams are seen not only as a hazard to quickly get rid of but also as a very costly menace to manage. However, looking at sanitation management from a resource recovery perspective provides an avenue for solutions with multiple co-benefits. Revenues from sanitation end-use products can act as an incentive for improving sanitation infrastructure while also covering part or all of the investment and operation costs for the same. Until now, estimating the potential for resource recovery from sanitation systems and technologies has largely been done on a case by case basis according to project or geography with no standardized universal tools or methodologies being used across the world. This study is aimed at developing a generic model for the rapid estimation of the quantities of various resources that can be recovered from sanitary waste streams in urban areas. Key waste streams from sanitation systems in low and middle income countries were identified and their major characterization parameters identified. The mathematical relationships between key waste stream characterization parameters and the potential amounts of resource products derived from treatment were determined and then used to develop the model in MS Excel. The model was then tested with waste stream flow rates and characterization data (for faecal sludge, sewage sludge and organic municipal solid waste) from the city of Kampala with two scenarios; the current collection amounts (390 m3 of faecal sludge, 66 tonnes of sewage sludge and 700 tonnes of organic solid waste) and the potential amounts with increased collection efficiency and coverage (900 m3 of faecal sludge, 282 tonnes of sewage sludge and 2199 tonnes of organic solid waste). The results were shared with Kampala city authorities to obtain feedback. The results showed that there is significan

To-date, sanitation has mainly been approached from a public and environmental health perspective and this implies that excreta and other organic waste streams are seen not only as a hazard to quickly get rid of but also as a very costly menace to manage. However, looking at sanitation management from a resource recovery perspective provides an avenue for solutions with multiple co-benefits. Revenues from sanitation end-use products can act as an incentive for improving sanitation infrastructure while also covering part or all of the investment and operation costs for the same. Until now, estimating the potential for resource recovery from sanitation systems and technologies has largely been done on a case by case basis according to project or geography with no standardized universal tools or methodologies being used across the world. This study is aimed at developing a generic model for the rapid estimation of the quantities of various resources that can be recovered from sanitary waste streams in urban areas. Key waste streams from sanitation systems in low and middle income countries were identified and their major characterization parameters identified. The mathematical relationships between key waste stream characterization parameters and the potential amounts of resource products derived from treatment were determined and then used to develop the model in MS Excel. The model was then tested with waste stream flow rates and characterization data (for faecal sludge, sewage sludge and organic municipal solid waste) from the city of Kampala with two scenarios; the current collection amounts (390 m3 of faecal sludge, 66 tonnes of sewage sludge and 700 tonnes of organic solid waste) and the potential amounts with increased collection efficiency and coverage (900 m3 of faecal sludge, 282 tonnes of sewage sludge and 2199 tonnes of organic solid waste). The results were shared with Kampala city authorities to obtain feedback. The results showed that there is significan

The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80Mgha-1) in laboratory pots, and different times of incubation of samples were tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20Mgha-1, such as an excessive increase of the soil pH and an increase of copper in the soil solution.

Purpose – The growth of Indian economy has brought with it significant increase in construction activities. These increased construction activities have further highlighted the problem of waste generation on construction sites. The purpose of this paper is to provide important insights and highlight some issues related to the implementation of effective waste management practices on construction sites in India. Design/methodology/approach – This paper presents two cases and results from semi-structured interviews which shed light on some of the major issues, challenges and drivers associated with the implementation of waste management in construction in India. Findings – One of the key findings was that client preference and enforcement of existing laws could actually facilitate the implementation of waste minimisation effectively. Some of the practices being followed, and which are gaining more popularity, are waste quantification, waste segregation, and the implementation of 3Rs (reduce, recycle, and reuse). Congested construction sites, sites in heavily built-up areas with no ability to have an alternate storage or staging location for materials, lack of ownership of waste due to the presence of multiple contractors on the construction site and lack of awareness and education among the construction workforce were regarded as major challenges associated with the implementation of waste minimisation practices in India.Research limitations/implications – The cases and the interviewees chosen were through the authors' links with the Indian Green Building Council (IGBC). The cases were LEED registered projects therefore issues dealing with green construction had been taken into account. These cases might not be representative of the entire country, as there are significantly high proportions of construction projects that are not as green, especially in smaller cities in India. However, the two cases do provide important insights and highlight some issues related to th

One of the important environmental issues raised recently in regard to coal ash reuse for highway construction purposes (e.g., embankment development) is that of worker, and public, exposure to radiation which might possibly be emitted by these types of residuals. Radiation emission is, in fact, a natural phenomenon for most materials, both natural and man-made, but in the case of coal ash residuals the process of combustion produces an inevitable concentration of radionuclides from the original virgin coal. INDOT’s corresponding environmental concern consequently focuses on the following basic question: does this magnification of radionuclides found within these coal ash residuals cause sufficiently high levels of radiation to impose harmful effects due to exposure? This research project subsequently addressed the associated issue of radiation emission by coal ash residuals generated within the State of Indiana, covering both fly ash and bottom ash materials. Samples were obtained at sixteen (16) different coal-fired power generating facilities within Indiana and subjected to a quantitative analysis of their associated gamma-ray emission levels. After identifying the responsible radionuclides, a conservative approximation was then developed for the worst-case potential occupational exposure with construction employees working on this type of highvolume, coal ash embankment. In turn, these potential emission levels were compared to those of other traditional construction materials and other common sources. The observed results indicated that these coal ash residuals did contain levels of gamma-ray emitters that were, in fact, higher than those of traditional construction materials (i.e., clay, sand, brick, and limestone). However, these levels of gamma-ray emission were not excessively high, and considerably below the limits respectively promulgated for public exposure and occupational exposure by the Environmental Protection Agency (100 mrem/yr for a single man-mad

One of the important environmental issues raised recently in regard to coal ash reuse for highway construction purposes (e.g., embankment development) is that of worker, and public, exposure to radiation which might possibly be emitted by these types of residuals. Radiation emission is, in fact, a natural phenomenon for most materials, both natural and man-made, but in the case of coal ash residuals the process of combustion produces an inevitable concentration of radionuclides from the original virgin coal. INDOT’s corresponding environmental concern consequently focuses on the following basic question: does this magnification of radionuclides found within these coal ash residuals cause sufficiently high levels of radiation to impose harmful effects due to exposure? This research project subsequently addressed the associated issue of radiation emission by coal ash residuals generated within the State of Indiana, covering both fly ash and bottom ash materials. Samples were obtained at sixteen (16) different coal-fired power generating facilities within Indiana and subjected to a quantitative analysis of their associated gamma-ray emission levels. After identifying the responsible radionuclides, a conservative approximation was then developed for the worst-case potential occupational exposure with construction employees working on this type of highvolume, coal ash embankment. In turn, these potential emission levels were compared to those of other traditional construction materials and other common sources. The observed results indicated that these coal ash residuals did contain levels of gamma-ray emitters that were, in fact, higher than those of traditional construction materials (i.e., clay, sand, brick, and limestone). However, these levels of gamma-ray emission were not excessively high, and considerably below the limits respectively promulgated for public exposure and occupational exposure by the Environmental Protection Agency (100 mrem/yr for a single man-mad

Although the constructive reuse of foundry residuals represents a decidedly beneficial goal with distinct economic and environmental benefits, potential end-users are nonetheless reluctant to use these residuals, given an inherent concern about potential unforeseen environmental liabilities. Results of foundry residual leachate characterization to date strongly suggest that many ferrous foundries are discarding sands whose quality is fully amenable to their future use with embankment construction and related high-volume highway development activities. In order to provide additional assurance as to the environmental impact of foundry residual reuse, the MicrotoxTM bioassay has been used to quantify the response of living organisms (e.g., the microorganism, Vibrio fischeri) to ferrous foundry residual leachates. This response has been compared with the response of the organism to “virgin” sands used in the foundry industry and as construction materials. Leachates from the majority of the ferrous foundries tested caused less inhibition of light production by the MicrotoxTM bacteria than did virgin sands. Taken literally, it appears that these sands are truly, “cleaner than dirt.” Furthermore, for those sands, no real differences were seen between system sands and fresh or aged waste sands. In a limited number of instances, however, there were clear and consistent indications that the tested waste foundry sands had released a contaminating toxin or toxins into the leachate waters, thereby resulting in a quantifiable depression in observed microbial activity. This innovative bioassay test appears to offer an efficient and expedient approach to ‘fingerprinting’ foundry locations for which constructive waste sand reuse could subsequently be pursued without undue concern about negative environmental impacts. Additionally, there appears to be a correlation between casting process (e.g., core binders, casting size, and casting temperature) and bacterial impact, such that foun

Although the constructive reuse of foundry residuals represents a decidedly beneficial goal with distinct economic and environmental benefits, potential end-users are nonetheless reluctant to use these residuals, given an inherent concern about potential unforeseen environmental liabilities. Results of foundry residual leachate characterization to date strongly suggest that many ferrous foundries are discarding sands whose quality is fully amenable to their future use with embankment construction and related high-volume highway development activities. In order to provide additional assurance as to the environmental impact of foundry residual reuse, the MicrotoxTM bioassay has been used to quantify the response of living organisms (e.g., the microorganism, Vibrio fischeri) to ferrous foundry residual leachates. This response has been compared with the response of the organism to “virgin” sands used in the foundry industry and as construction materials. Leachates from the majority of the ferrous foundries tested caused less inhibition of light production by the MicrotoxTM bacteria than did virgin sands. Taken literally, it appears that these sands are truly, “cleaner than dirt.” Furthermore, for those sands, no real differences were seen between system sands and fresh or aged waste sands. In a limited number of instances, however, there were clear and consistent indications that the tested waste foundry sands had released a contaminating toxin or toxins into the leachate waters, thereby resulting in a quantifiable depression in observed microbial activity. This innovative bioassay test appears to offer an efficient and expedient approach to ‘fingerprinting’ foundry locations for which constructive waste sand reuse could subsequently be pursued without undue concern about negative environmental impacts. Additionally, there appears to be a correlation between casting process (e.g., core binders, casting size, and casting temperature) and bacterial impact, such that foun