Sources, sinks and transformations of plastics in our oceans: review, management strategies and modelling

Currently, 60–80 % of litter is plastic, and almost 10 % ends up in the ocean directly or indirectly. Plastics often suffer from photooxidation producing microplastics and these microplastics derived from the breakdown of larger plastics are called secondary microplastics. These compounds simply cannot be extracted from the oceans, and once mixed, they enter the food chain and may have toxic effects. This work reviews the current existing information on the topic in the scientific literature. Then, the current plastic management strategies in the marine environment are analysed, with the objective of identifying possible needs and improvements from a sustainable point of view, and to define new approaches. Simultaneously, a material flows analysis in different media of the marine environment is carried out using system dynamics. A preliminary model of plastics mobilization into the ocean to other media of the marine environment (like sediments and biota) is developed and validated with the existing data from the previous steps of the work. This work expands the current knowledge on the plastics management, their transformations and accumulation in the marine environment and the harmful effects on it. Likewise, preliminary dynamic model of mobilization of plastics in the ocean is implemented, run, and validated. The developed model can be used to predict trends in the distribution of the plastics in the ocean with time. In addition, the most important reservoirs of plastics in the ocean can be observed. Although plastics undergo transformations in the marine environment, it is not a means of disposal since most of them are non-biodegradable. Most plastics accumulate on the seabed. The proportion of microplastics found in sediments is higher than that of macroplasticsS

Design of a sustainable house including the requisites of the Spanish Regulation

Abstract: Green Building is a philosophy aiming to maintain a high quality of the built environment while optimizing the use of resources, both materials and energy. Related to green building, sustainable construction consists in the creation and operation of a healthy built environment giving rise to high-performance green buildings. These building concepts have already been taken into account by the European Union (EU) that has promoted the use of alternative energies, thermal insulation and responsible consumption programs, among others. The Directive 2002/91/EC came into force to regulate energy efficiency in new buildings. Member States transposed this text to their legal systems, considering the particularities of to their territories, geography, economy and society. In Spain, the Spanish Technical Building Code (CTE-Código Técnico de Edificación) promotes sustainable building. Other regulations regarding energy buildings certification, energy efficiency or renewable energy promotion have already been adopted. This work presents a house designed taking into account some aspects of the sustainable house design, and compares it with a reference house. These aspects include the thermal requirements of the house following a simplified option established in the basic documents HE1 (Limitation of the energetic demand) and HE4 (Minimal solar contribution for heating domestic water) of the Spanish Building Technical Cod

Black Holes and Objectivity

La primera imatge directa d’un forat negre, presa l’abril de 2019, representa un canvi de paradigma no solament pel que fa a les imatges científiques, sinó també en l’apreciació cultural del desconegut. Per a aconseguir aquesta fita va caldre comptar amb una col·laboració tecnològica global a una escala mai vista, i també l’aplicació de noves i rigoroses formes d’objectivitat. Aquest text vol reflexionar sobre la necessitat que els complexos i esotèrics aparells i les observacions científiques de la ciència fonamental més recents vagin acompanyats d’una major consciència de l’objectivitat i de la implementació de la transdisciplinarietat.The first ever direct image of a black hole, released in April 2019, was a paradigm shift not just in scientific imaging, but also in the cultural appreciation of the unknown. Its realisation demanded a global technological collaboration on hitherto unseen scales and also the application of new and rigorous forms of objectivity. This text discusses how complex and esoteric planet-wide scientific apparatus and observations at the cutting edge of fundamental science demand a heightened awareness of objectivity and the implementation of transdisciplinarity.La primera imagen directa de un agujero negro, tomada en abril de 2019, representa un cambio de paradigma no solo en lo que respecta a las imágenes científicas, sino también en la apreciación cultural de lo desconocido. Para lograr este hito fue necesario contar con una colaboración tecnológica global a una escala nunca vista, así como la aplicación de nuevas y rigurosas formas de objetividad. Este texto quiere reflexionar sobre la necesidad de que los complejos y esotéricos aparatos y las observaciones científicas de la ciencia fundamental más recientes vayan acompañados de una mayor conciencia de la objetividad y de la implementación de la transdisciplinariedad

Black Holes and Objectivity

The first ever direct image of a black hole, released in April 2019, was a paradigm shift not just in scientific imaging, but also in the cultural appreciation of the unknown. Its realisation demanded a global technological collaboration on hitherto unseen scales and also the application of new and rigorous forms of objectivity. This text discusses how complex and esoteric planet-wide scientific apparatus and observations at the cutting edge of fundamental science demand a heightened awareness of objectivity and the implementation of transdisciplinarity

Development and Application of a Thermal Comfort Model in Buildings

Buildings are one of the systems that more energy consumed in the European Union. The study of the thermal envelope is interesting in order to reduce the energy losses. For that, a mathematical model able to predict the system response to external temperature variations is developed. With the mathematical model, different thermal envelope elements of a building based on the lag and the cushioning of the resultant wave can be characterized. In addition, it is important to analyse where the insulation is placed, because when the insulation is outside and the thermal mass is inside, the system produces a response with smooth temperature variations than when the insulation is inside. Therefore, placing the outside insulation generates more steady indoor temperatures, increasing the thermal comfort inside the building. To complete the mathematical model that allows predicting the temperature inside a building taking into account the solar inputs and the thermal inertia of the building. This study will help to establish the optimum design parameters in order to build sustainable and comfortable buildings. Furthermore, it will take one step forward in the construction of nearly Zero-Energy Buildings

The Role of a Hazardous Waste Intermediate Management Plant in the Circularity of Products

Zero-pollution goals and the reduction in environmental pressures related to production and consumption have become a priority in recent environmental policies such as the 8th European Environment Action Program proposal. Adapting current industrial processes is essential to this transition towards a regenerative economy. This work presents a redesign plan for an industrial system that includes mechanical workshops and a hazardous waste intermediate management plant, covering all management activities (both off-site and on-site), such as collection, transport, and treatment. The waste management hierarchy is modified/amplified considering the original definition and the circular economy focus. This includes the improvement of existing processes and/or the design of new sustainable processes from waste to energy and useful materials, with different foci (integrated pollution prevention and control, industrial ecology, the circular economy, system dynamics, and life-cycle thinking (LCT)) and different tools employed (Best Available Techniques inventory (BAT), process simulation, BAT analysis, industrial symbiosis, dynamic material and energy flow analysis, and LCT tools). These tools help us to improve the sustainability of waste to energy and useful materials processes and improve symbiotic behaviour in the industrial system. This study shows the real possibility of achieving the circularity of products, transforming the waste sector into a productive one. Meanwhile, it contributes to the extinction of the traditional concept of waste

Analysis of biowaste-based materials in the construction sector: evaluation of thermal behaviour and life cycle assessment (LCA)

The objective of the work is to evaluate the thermal behaviour and the environmental impact of selected building biowaste-based materials, mainly biomass from agrowaste. An evaluation of the state of the art of the materials used from waste or biomass in the construction of buildings is carried out. The selected building materials are based on data availability: hemp concrete, isotex, bricks with olive core flour (OCF), bricks with wheat straw (WS). Subsequently, thermal behaviour is evaluated as a function of decrement factor, time lag and as an application in the thermal envelope of a building. Finally, a life cycle assessment of each material is carried out, including the calculation of the following indicators: non-renewable energy, cumulative energy demand and global warming potential. Hemp concrete and isotex are the materials with better thermal behaviour (lower decrement factor and greater time lag) like conventional materials, but with lower environmental impact. Regarding bricks, mixtures of 8% OCF and 7%WS generate more stable indoor temperatures than 4% OCF and 3%WS. Compared with conventional materials, building materials with incorporated biomass have better thermal behaviour and allow the construction of buildings with lower life cycle impactOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research did not receive any specific grant from funding agencies in the public, commercial, or not for-profit sectorsS

Contribution to understanding the influence of fires on the mercury cycle: systematic review, dynamic modelling and application to sustainable hypothetical scenarios

Mercury (Hg) mobilization and accumulation in the environment is directly related to forest fires. Biomass burning accounts for about 13% of the total contribution of Hg from natural sources. The aim of this work is to contribute to the knowledge of how wildfires modify mercury compounds behaviour and the effects it has in the Hg cycle, based on a systematic bibliographic review and analysis. Systems dynamics is an adequate focus to analyze the mobilization of Hg due to wildfires, which meets all the requirements to be studied by multimedia modelling. The development and application for the first time of a dynamic multimedia model of Hg taking into account specifically the influences of wildfires is one of the novelties of this work. Different scenarios show that an increase in the number of fires will consequently increase the mercury emitted into the atmosphere, modifying its natural cycle, producing a long-term modification of Hg compositions and concentrations in the different media. Hg movement caused by wildfires can cause complications in living beings and alter the ecosystems. This study found that the Hg soil content could as well be an indicator to measure the impact of fire on the environment. This model can also be generalized to conduct additional studies under comparable conditions, helping to understand the importance of forest fires in global Hg cyclesOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer NatureS

Towards sustainable re-construction systems: from waste ruins to eco-efficient buildings

Building reconstruction projects are mainly motivated by social factors, without a deep evaluation of the Best Available Techniques. The main aim of this work is to analyze the advantages of defining sustainable retrofitted buildings, previously building the edifice, by using methodologies towards sustainable systems. A real re-constructed building is considered as a case study. Three scenarios are investigated to analyze its sustainability, including the waste ruins of the old building (Scenario 1), the current re-constructed building (Scenario 2), and a hypothetical sustainable retrofitted building (Scenario 3). Firstly, the current energy consumption is studied including heating flow through walls (thermal bridges and condensation risk) as well as operational costs. Secondly, a new scenario is proposed adding passive solutions to this existing building, to improve its energy efficiency; also, energy consumption and costs of the refurbishment are analyzed. Results show that Scenario 1 leads to a bad image of a city involving the environment and social fields. Scenario 2 entails expensive operational costs. On the other hand, Scenario 3 results in approximately 90% of cost savings in heating energy demand, which would be traduced on high economic savings. Taken into account not only economic factors but environmental and social ones, it can be concluded that it is more sustainable and profitable constructing an efficient building from the beginning by using waste ruins and simulation software despite refurbishing a re-built edifice