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Salvaging Buildings : reclaiming a livelihood from the excesses of Istanbul's mass urbanization
(2023)
Turkey’s demolition waste management is, to a great extent, dependent on çıkmacıs (reclaimers) who salvage condemned buildings for raw materials and architectural elements. Its urbanization history is full of key moments marked by building demolitions, which became a necessary material resource for informal urbanization. As early as the 1970s, the çıkmacıs helped the gecekondus [squatter houses] by supplying second-hand building materials and construction loans. They managed to turn a lack of infrastructure into an advantage and remain very adaptable to the ever-changing conditions of neo-liberalized urbanization. They depend on solidarity networks and other informal resources. Assemblage thinking helps to redefine the concept of informality, understand the relational dynamics between various actors, and focus on the agency of materials. The empirical data gained from ‘follow the thing’ ethnographic research in Turkey and Georgia reveals the double lives of çıkmacıs who move between village and city. Additionally, by following the example of a reclaimed window frame’s journey from Istanbul to Tbilisi, we can more clearly see the second-hand trade network in the context of urbanization and incremental architecture. In the context of waste’s materiality, the empirical part of the research shows the symbiotic relationship between çıkmacıs and the discarded demolition materials.
The present study deals with the phenomenological observation of the corrosion of the positive electrode foil of lithium-ion batteries containing LiNi0.6Co0.2Mn0.2O2 (NMC) as cathode material. Due to the presence of moisture, localized water accumulation is formed on the NMC surface. The water absorbed by the electrolyte reacts with the NMC under Li+/H+ exchange and the resulting pH increase leads to dissolution of the carrier foil and characteristic salt-like blooms on the NMC surface. With the increase in the relative area occupied by the holes in the aluminum foil per time, a sufficiently suitable parameter was found with which to quantitatively determine the extent of corrosion. The degree of degradation depends on time and ambient humidity. It was shown that functional recycling with the water jet method is no longer applicable for degraded foils, since the mechanical stability of the foils decreases as corrosion progresses. Lithium, aluminum, sulfur and oxygen were detected in the blooms using SEM–EDX and Laser-Induced-Breakdown-Spectroscopy (LIBS). The underlying NMC layer was found to contain mainly aluminum and significantly lower lithium content than the non-degraded material. SEM and Raman microscopy analyses also showed that the active material is also locally degraded and therefore no longer suitable for functional recycling.
Der vorliegende Review Artikel thematisiert die Rückführung von abgelagerten Ressourcen aus Deponien und es werden verschiedene Deponieklassen in Anlehnung an die deutsche Deponieverordnung erläutert. Deutschland dient als positives Beispiel für die Errichtung sicherer Deponien, welche je nach Ablagerungsmaterial in unterschiedliche Deponieklassen unterteilt werden. Trotz der fortschrittlichen Ablagerung im internationalen Vergleich ist der Unterhalt einer solchen Deponie als nicht nachhaltig einzustufen. Die Rückgewinnung von Ressourcen ist eine Möglichkeit, die Nachhaltigkeit zu erhöhen. Allerdings ist es umständlich, Deponien zurückzubauen und den Abfall zu sortieren sowie aufzubereiten. Durch verschiedene Aufbereitungsverfahren kann zwischen unterschiedlichen Abfallarten differenziert und so der Output an die gegebene Situation angepasst werden. Unter den verschiedenen Wertstofffraktionen versprechen insbesondere Metalle einen großen Erlös beim Weiterverkauf. Bei Nichtmetallen steht die energetische Nutzung im Vordergrund. Neben den betraglichen Erlösen sind Opportunitätskosten von großer Bedeutung. Neben vermiedenen Kosten für die Instandhaltung werden auch sozialen und ökologischen Folgen reduziert. So können Landflächen zurückgewonnen werden, die als Baugrund genutzt werden können. Die effektive Verwertung von Abfall führt zu einer Reduktion, wodurch die ökologischen Folgen von zu viel Abfall eingegrenzt werden. Deponiebergbau findet schon in vielen Regionen der Welt seine Anwendung. In Anbetracht der Tatsache, dass die Ressourcenknappheit und der steigende Bedarf eine Einschränkung im Konsum hervorrufen können, wird die weitere Erforschung und die technische Umsetzung des Deponiebergbaus zunehmend wichtig.
Aufgrund einer weltweit geringen Recyclingquote der Kunststoffe von 9% und Belastung von Luft, Wasser und Boden, ist es notwendig das Recycling und alles darum zu optimieren. Das Ziel der vorliegenden Arbeit war es unterschiedliche Methoden des Recyclings und Prozesse vor dem Recycling, wie die Sortierung und Reinigung zu analysieren und in Bezug auf ihre Effizienz zu bewerten. Im Rahmen dieser Untersuchung wurde das Sortierverfahren der Flotationstrennung mit diversen Ausgangsstoffen genauer untersucht. Hier beweisen experimentelle Ergebnisse eine maximale Rückgewinnungsrate von 99,34%. Zudem wurde auch die beste sensorgestützte Sortierungsmethode im Zusammenhang der verwendeten Literatur genannt. Dieser Mechanismus nennt sich VIP-Scores-Verfahren. Zur Thematik Reinigung von kontaminierten Kunststoffen gibt es ein neuartiges Verfahren zur wasserlosen Reinigung mit Flusssand. Diese Methodik erlaubt eine Reinigungsrate von bis zu 97% bei einer mittleren Partikelgröße. Dazu geht diese Arbeit auf Verfahren des mechanischen, chemisch und thermischen Recyclings ein. Mechanisches Recycling bringt eine hohe Energierückgewinnungsquote mit sich. Jedoch müssen für die Durchführung dieser Prozess einige Bedingungen erfüllt sein. Das thermochemische Verfahren der hydrothermalen Verflüssigung bietet dagegen Möglichkeiten auch gemischte Kunststoffe zu verarbeiten. Des Weiteren ist das Upcycling von Kunststoffen mittels enzymatischer Depolymerisation möglich. Der Stand der Forschung dieser Arbeit beschränkt sich auf den Zeitraum 01.01.2020- 14.11.2022.
Die Habilitationsschrift zielt darauf ab, den Erkenntnisstand zur Bauteilwiederverwendung (Produktrecycling) und zum Materialrecycling (stoffliches Recycling) aufzuzeigen. Wissenschaftlich fundiert und Impuls gebend werden unter Nachhaltigkeitsprämissen potenzielle Wiederverwendungsmöglichkeiten für großformatige Betonbauteile und Verwertungsmöglichkeiten für Bauschuttfraktionen herausgearbeitet. Die Untersuchungen konzentrieren sich auf die Rohbaukonstruktion industriell errichteter Wohnbauten der DDR-Zeit, die zum Rückbau anstehen. Bewertet werden baustoff-, -technische,- rechtliche, -technologische, wirtschaftliche, ökologische sowie logistische Kriterien für das Produkt- und Materialrecycling. Anhand von untersuchten Szenarien wird auch verdeutlicht, dass Ressourcen- und Energieeffizienz miteinander vernetzt sind. Im Rahmen des Materialrecyclings wird aus Ressourceneffizienzgründen vordergründig die Verwertung von rezyklierten Gesteinskörnungen zur Herstellung von Beton diskutiert. Des Weiteren werden hauptsächlich die in Plattenbauten anzutreffenden schadstoffhaltigen Baustoffe aufgezeigt inklusive deren gesundheitliche und abfallwirtschaftliche Auswirkungen und Behandlungsoptionen. Im Ergebnis der Analysen wird empfohlen, wie Bauten zukunftsorientiert zu errichten sind und dass sich das Lehrangebot an die sich verändernden Bedingungen, unter dem Aspekt nachhaltig zu bauen/Schließung von Stoffkreisläufen, verändern muss.
The significance in the production of bio-based products is enhanced with the abundance and renewability of biogenous raw and residue materials in comparison to the depleting fossil fuels especially in producing environment friendly products and their applications in energy (CO2-neutral) as well as material applications. This work concentrates mainly on the production of bio-based products through innovative processing and refinement of biogenous residues originating from agricultural (cereal straws), industrial (lignin from black liquors) and biotechnological (biogas residues) processes. The innovative processing and refinement of the processes and their end-products solve the challenges which were not possible within the conventional processes. The innovative processes improve the cascading as well as sustainable utilization possibilities with a simultaneous value addition of the residues. Converting biogenous residues into a valuable end-product requires various preprocessing of the raw materials and are material specific (physical and chemical compositions). Agglomeration of theses residues is chosen as one of the main innovative processes making the handling of the products easier. Agglomeration in this work is carried out using press / densification processes in case of cereal straws, build-up processes in case of black liquors and encapsulation processes in case of biotechnological residues.
Recycling and material recovery are gaining more grounds in applicability as viable options to sustainable solid waste management especially in Municipal Solid Waste Management (MSWM) schemes. In this dissertation a critical analyzes is made of the MSWM problem in Cameroon and an assessment of the role Small- and Medium-Size Enterprises have been playing in the area of recycling and material recovery. The main research methods applied in this research include: fieldwork, administration of questionnaires, interview and literature review. Using two case study localities (Limbe and Buea municipalities), the various practices in MSWM are elaborated, the constraints and challenges faced by management discussed and proposals for either expanding/upgrading existing schemes to be more sustainable as well as strategies to initiate new systems presented. Innovations within collection systems such as the introduction of household bins and specialized collection of specific waste could be quite beneficial to existing schemes. Waste Electrical and Electronic Equipment (WEEE) which constitute one of the fastest growing waste streams presents greater management challenges. Two case study localities (Buea and Kumba) are used to analyze the problem of WEEE in Cameroon. An overview of the handling of Electrical and Electronic Equipment (EEE) at end-of-life (EoL) in Cameroon is made with special focus on households and repair units. At household level, WEEE is disposed of alongside other waste arisings in the available disposal facilities for given household. Repair units represent a very vital connection between dysfunctional EEE and EoL forms as all users of EEE tend to bring these devices to these units for repairs. An inventory of the various EEE at repair units for these two localities shows that above 40% percent of such equipments are totally out of use. In Kumba, Classes 1 and 4 EEE (according to EU WEEE directive classification) dominate while class 3 is almost absent. In Buea, Class 3 and 4 are dominant. These results show that socio-cultural, economic and even climatic factors influence the choice of EEE that people in this area acquire. The intense level of repair activities and recovery of useful parts by repair units show that there exist adaptable options to handle WEEE in especially economically and environmentally beneficial ways. The recycling of aluminum for production of household utensils represents a very basic and adaptive industrial set-up, which can easily be operated and run at very cheap cost and with a little manpower. While this venture seems apparently successful in economic terms as an option to poverty alleviation through income generation, it is plagued by some problems which, if given due consideration will render it a prospective option for poverty alleviation (through small enterprise business development) and environmental sustainability (as an option to sustainable MSWM). In this dissertation, a model is thus presented, which can be utilized by stakeholders to improve on the sector. An assessment of efforts and constraints to implementing comprehensive recycling and recovery schemes in Cameroon was also carried out. Results show that there are existing practices on which comprehensive recycling and recovery can be built upon that would be beneficial to both councils and engaged schemes – mostly SMEs and NGOs. The challenges faced and likely to be faced and the way forward to implementing any broad scale recovery and recycling are presented. If municipal councils choose to operate existing MSWM schemes without significant changes, then collective collaboration will be highly required. Such collaboration will present benefits to both waste collection and disposal. On the other hand, if they wish to expand schemes or create new schemes, adaptive innovation would be highly recommended. Such adaptive innovation would have to incorporate local practices and approaches of MSWM as well as socio-economic considerations so as to ensure new or expanded schemes survive within local socio-economic context. A greater challenge in enhancing recycling and material recovery in particular and MSWM in general, in Cameroon is on the role the government takes on designing appropriate policies and legislative frameworks to cover such activities in economically and ecological beneficial ways. In the absence of these, SMEs, councils and NGOs (working in partnership with other specialized groups) concerned with activities related to recycling and material recovery may be left with the option of regulating activities within their sectors as such activities stand to alleviate poverty and also present ecological benefits.
Implementation of End-of-Life Vehicle’s Recycling for Developing Countries: Case Study, Mexico
(2008)
Currently, the Directive 2000/53/EC regulates the ELV management in 27 countries in Europe, and for the forthcoming years, more accession countries are foreseen. Since, the international nature of automotive industry, the Directive has affected industries beyond the EU. Hence, countries with important national-based automotive industry are moving towards the accomplishment of this legislation, in order to keep their competitiveness in European markets. The ELV chain in the EU is a complex system, which involves several commercial relationships between different sectors. The generation of ELV in the EU-15 was around 11.4 million units in 2005. The total number of ELV generated, considering the accessing countries, is still unknown. The number of treated ELV in the EU-15 was 7.7 million units. There are some obstacles to be overcome by ELV management already in implementation in the EU. The main difficulties are related to the reluctance of car-manufacture industry to implement Directive’s provisions related to: ban of use of specific substances in automotive applications, and about recycling quotas. Another obstacle is the export of ELV from the EU, which represents a loss in input material for the system. The case of the USA, regarding the ELV management, has very different connotations than the implemented system in the EU. The current ELV management in the USA does not have specific regulations regarding the collection and recycling of ELV. The structure of the ELV chain in the USA is similar to its counterpart in the EU. The main difference lies in dismantling and post-shredder sectors. The 80% of dismantling industry is composed of salvage/scrap yards performing no-standardized operations, and the remaining 20% is represented by high value parts dismantlers. One special feature of the system is the classification of ASR as no-hazardous waste which generates almost no incentives for further treatment. The current system of ELV management in the USA works with relative efficiency. However, there are still items to be improved, e.g. poor dismantling practices in a big number of dismantling facilities (scrap yards), use of hazardous materials in car-manufacture, disposal of ASR as non-hazardous waste, scrap tyres, etc. The ELV problem has different connotation in developing countries like Mexico, than in industrialized countries. Problems, like illegal introduction of used cars from the USA to Mexico and poor practices in the management of ELV, affect the Mexican economy, environment and society. In Mexico, there exists no specific legislation to regulate the Management of ELV. This kind of product, at its End-of-Life stage and wastes generated by its treatment, has been ruled by general laws before the year 2004. More recently a semi-specific law has been addressed to solid wastes, the LGPGIR. The structure of ELV chain in Mexico is similar to its counterpart in the USA and the EU, except for an additional stage. The present work depicts the available information about the number of Mexican operators, at every stage of ELV management. The described evidence presents a deficient management of ELV in Mexico. The current management allows a maximum recycling rate of 75%, which mainly corresponds to the ferrous fraction content in vehicles which enters to the management system. The present work develops a proposal for a suitable system to manage End-of-Life Vehicles (ELV) in a developing country, case study Mexico. This, is divided in three main parts. As a first step, the proposal estimates the future numbers of ELV generated in Mexico, which are estimated in a current ELV generation of around 687,000 vehicles by 2007, and by 2020 in the range of 1.1 to 1.3 million units per year. The second step is to propose a structure for the ELV chain in Mexico. The proposed structure describes the recommended operations, equipment and facilities’ configuration at every stage of the management. The third step of the proposal is the configuration of strategic facility network at every stage of ELV management in Mexico. The system is configured under assumption of three different scenarios, i.e. 100%, 90% and 75% of covered demand for ELV management. The algorithm is identified for this specific problem as a Fixed Charge Facility Location Problem. The algorithm is solved through Facility Location Software SITATION©. The results show the optimal number of facilities at every stage of the management, to cover the demand for ELV management considered in the different scenarios. The fourth part is to propose a model to finance the ELV management in Mexico. The main features of this scheme are explained, as well as its advantages, disadvantages and incentives thought to be triggered into the Mexican ELV chain.
Zielstellung war die wissenschaftliche Erarbeitung und Aufbereitung von Grundlagen für die Demontage von Plattenbauten mit anschließender Wiederverwendung ausgewählter Fertigteile. Die Arbeit enthält nachfolgende Schwerpunkte: prinzipielle Abbruch- und Rückbauverfahren, bestehende Bestimmungen, Erarbeitung von Rückbautechnologien, Entwicklung einer Abbruch- und Demontageanweisung, Vorbereitung der Baustellenprozesse, Untersuchungen zu Demontagehilfsmitteln, zu Trennverfahren sowie zum Hebezeugeinsatz und Transport, Eignung der Fertigteile zur Remontage, Modell zur Ermittlung der Restgebrauchswerteigenschaften, Handlungsanleitungen zur Vorbereitung und Durchführung von De- und Remontagen Es schließen sich die Auswertung der Demontage/Remontage eines Musterprojektes einschließlich Arbeitsstudien sowie Untersuchungen zu den Demontage- und Remontagekosten, zur Verallgemeinerung und Übertragbarkeit der Ergebnisse an.
Environmental consciousness of the modern society has projected recycling into the limelight as it has considerable potential for saving the earth’s limited resources, and potential offers opportunities for reducing environmental pollution. This dissertation presents a methodology developed for assessing the recycling-orientation of products in product design and a tool for carrying out the assessment. The design criteria for the recycling-orientation of products are formulated by investigating and analysing relevant product design constraints, including standards and regulations that facilitate and ease recycling. Essentially, this final dissertation comprises two parts: (1) the dissertation manuscript, (2) the assessment tool, “software.” The dissertation expatiates on the methodology employed and its implementation details for assessing the recycling-orientation of products both qualitatively and quantitatively at the design stage. Several recycling related product design standards were taken into account, including WEEE, RoHS, Eco-design, and DFR. The software comprises a series of decision stages; each stage controls different active facets of its functionalities. The assessment of the recycling-orientation of product design is achieved by virtually modeling a product from the product profile. The detail of how this works is demonstrated with a case problem. The opportunity for future development and software upgrading are discussed at the end.