1,720,966 research outputs found
Life Cycle Assessment del processo di valorizzazione di rifiuti organici mediante l’utilizzo di insetti per l’ottenimento di bioplastiche
No full textL'aumento della produzione di rifiuti è una delle maggiori preoccupazioni in molte aree del mondo. Una rigida normativa sulla tracciabilità dei rifiuti, che ne impedisce usi alternativi e comporta costi non indifferenti, ed una crescente domanda di fonti rinnovabili per la produzione di energia, prodotti chimici, combustibili e materiali, sta portando ad una forte richiesta di tecnologie innovative per la gestione e la valorizzazione dei rifiuti, in particolare per deiezioni/scarti zootecnici e frazione organica dei rifiuti urbani.
Negli ultimi anni sono state proposte strategie alternative per la valorizzazione di tali materiali di scarto che comprendono approcci termochimici (ad esempio pirolisi e trattamento idrotermico), l'uso di fonti energetiche meno convenzionali come microonde, ultrasuoni o energia meccanica, fermentazione e digestione microbica insieme ad ulteriori bio-based strategy, tra cui la bioconversione per mezzo di insetti rappresenta sicuramente una delle tecniche più promettenti. In effetti la conversione delle biomasse di rifiuti organici in preziose biomolecole è una caratteristica peculiare di diversi tipi di insetti. Tra questi insetti l’Hermetia illucens (Linneus 1758, meglio noto come Black Soldier Fly - BSF) rappresenta un esempio eccellente, con numerosi vantaggi rispetto ad altre specie. BSF è una mosca non nociva (gli adulti vivono solo per pochi giorni, non si nutrono e non trasmettono agenti patogeni), le cui larve sono in grado di lavorare e svilupparsi molto rapidamente su substrati diversi tra cui sottoprodotti agricoli, escrementi di bestiame e rifiuti organici, limitando in modo significativo la crescita batterica e lo sviluppo di cattivi odori. Nonostante i problemi o le considerazioni ambientali e sulla salute umana, le prepupe di BSF sono buone fonti di lipidi, proteine e chitina, che sono state sfruttate negli ultimi anni nella produzione di biodiesel, mangimi e bioplastiche. In questo studio la pollina viene sfruttata per allevare prepupe di BSF che verranno frazionate in laboratorio per purificare la frazione proteica, lipidica e quella chitinosa. A partire dalle proteine si è individuata una appropriata miscela di componenti/additivi per l’ottenimento di bioplastiche funzionali ad un loro uso in agricoltura. In particolare lo scopo di questo lavoro è la valutazione ambientale mediante analisi LCA di tutti i diversi processi, dall'allevamento di BSF alla produzione di bioplastiche, passando attraverso la fase di isolamento, caratterizzazione ed estrazione della frazione lipidica, proteica e chitinosa.
Sebbene il numero di studi che hanno valutato la bioconversione dei rifiuti organici tramite insetti (in particolare BSF) sia cresciuto considerevolmente negli ultimi anni, solo alcuni di essi riportano l’applicazione della metodologia LCA, seppur limitatamente al solo processo di bioconversione, valutando solo l'impatto ambientale associato alla produzione di prepupe di BSF e confrontandolo con fonti di alimentazione più convenzionali. Il presente studio, applicando l'analisi LCA a un sistema complesso, che parte dall’allevamento fino ad arrivare alla produzione di bioplastiche, ha l'obiettivo di analizzare in modo sperimentale alcuni aspetti metodologici che non sono ancora stati approfonditi fino ad oggi. Il progetto rappresenta perciò una sfida da affrontare con l'approccio del Life Cycle Thinking, ma è anche una opportunità per studiare gli aspetti deboli degli attuali modelli di valutazione ambientale basati sull’analisi LCA, come ad esempio le emissioni locali e indoor, per le quali è stato proposto un framework di calcolo (per il comparto aria) sviluppato a partire dai metodi EcoIndicator99, USEtox e dal modello Gaussian Plume Modeling.The increasing in waste production is among the major concern in many areas around the world.
A strict regulations in relation to its traceability, which prevents any alternative uses and carries considerable costs, and the increasing demand for renewable sources for production of energy, chemicals, fuels and materials, is leading to a strong demand for innovative technologies for the management and valorisation of waste, particularly for livestock manure and organic fractions of municipal waste.
In the last years, alternative strategies for enhancing such waste materials have been proposed that include thermochemical approaches (for example pyrolysis and hydrothermal treatment), the use of less conventional energy sources such as microwaves, ultrasounds or energy mechanical, fermentation and microbial digestion together with additional bio-based strategies, among which bioconversion by insects is certainly one of the most promising techniques. Indeed conversion of organic waste biomasses into valuable biomolecules is a peculiar characteristic of several kinds of insects.
Among these insects Hermetia illucens (Linneus 1758, better known as Black Soldier Fly - BSF) represents an excellent example, possessing several advantages with respect to other species. Black Soldier Fly is a non-pest fly (adults live for a few days only, they do not feed and do not transmit pathogens), whose larvae are able to process and to develop very quickly on different substrates, including agricultural by-products, livestock excrements and organic waste, significantly restraining bacterial growth and bad odours development. Despite environmental and human health issues or considerations, BSFs prepupae are good sources of lipids, proteins and chitin, which have been exploited in recent years in the production of biodiesel, feed and bioplastics. In this study poultry manure is exploited to breed BSFs prepupae which will be fractioned in a laboratory in order to purify the protein, lipid and chitin fraction. Starting from BSF proteins an appropriate mixture of components and additives was identified to obtain bioplastics functional to their use in agriculture. Particularly the aim of this work is the environmental assessment through LCA analysis of all of the different processes from BSFs breeding to the bioplastics production, by passing through the phase of isolation, characterization and extraction of protein, lipid and chitinous fraction.
Although, the number of studies evaluating bioconversion of organic waste by insects (in particular by BSFs) has considerably grown during the recent years, only a few of them reported the application of LCA methodology, limitedly to the only bioconversion process, thus assessing the environmental impact associated with the production of BSF prepupae, and comparing it with more conventional feed sources. The present study, applying the LCA to a complex system, which starts from breeding up to the production of bioplastics, aims to experimentally analyze some methodological aspects that have not yet been studied in depth to date. The project is a challenge to be tackled with a Life Cycle Thinking approach, but it is also an opportunity to study the weak aspects of the current LCA-based environmental assessment models, for example the local and indoor emissions, for which, a calculation framework (for air compartment) was developed based on the EcoIndicator99 and USEtox methods and the model Gaussian Plume Modeling
ENVIRONMENTAL FOOTPRINT IN THE PRODUCTION OF RECYCLED WOOL
No full textWe computed the Product Environmental Footprint (PEF) to identify the environmental performance of recycled wool by means of data belonging to a real case study in Italy. First, we analyzed inventory data quality by computing the data quality rating (DQR) index, according to the criteria provided by the PEF protocol. Quality of specific and generic data (selected from the Ecoinvent database) was evaluated as excellent and good, respectively. We then quantified the impacts related to each relevant production process via Life Cycle Assessment (LCA). Specifically, we identified four main processes involved in the production of recycled wool for the selected case study: (i) clippings supply, (ii) clippings preparation, (iii) ragging, and (iv) dyeing. In the production of recycled wool, the rate of incoming materials subject to dyeing decreases to about 40%. Nevertheless, LCA revealed that this process is the most critical due to the high energy consumption and chemical substances employed. This result was confirmed by further analysis based on the Eco-indicator approach and the single point eco-indicator score. In particular, we found that environmental impacts associated with the production of recycled wool are mainly related to the following categories: (i) depletion of abiotic resources, (ii) inorganic particles released into the air, (iii) climate change, and (iv) human toxicity. We quantified that the contribution of the dyeing process to the relevant impact categories is higher than 75%. These results revealed how the use of recycled materials strongly increases the environmental performance associated with wool production, reducing the impact of the most environmental demanding processes
Life Cycle Assessment of an adhesive for the laying of ceramic tiles
No full textThe building sector is still largely dominated by recourse to natural resources with growing consumes: the necessary request of natural aggregates generate a strong impact on the territory because of extractive activities.
The growing attention and interest towards the environment led to a wider interest in reusing and recycling building materials. Consequently it is necessary to pay attention on the contribution that the secondary aggregates may lead to the satisfaction of the building society needs. For this reason it is necessary evaluate the environmental bounders associated to the necessary industrial operation to obtain the secondary raw materials, with respect the natural aggregates, obtained from extractive activities. To investigate the environmental performance of both secondary raw materials and natural aggregates it is important to adopt the life cycle approach. A product is usually defined as eco-friendly when it is solely composed by recycled materials, since the consumption of raw materials and the production of waste are limited. However, in this way, it cannot taken into account of the energy consumption during the reprocessing, that often reduces the advantage of the raw material savings
The environmental impact of cleaning materials and technologies in heritage buildings conservation
No full textHistoric buildings constitute a large amount of the European building stock and their preservation is of paramount importance for cultural, economic and also environmental reasons, as their conservation is regarded as more sustainable with respect to demolition and reconstruction. However, historic buildings require frequent repair and conservation works, whose environmental impact is still to be evaluated. In the present paper the sustainability of conservation intervention is evaluated by the LCA analysis method, focusing in particular on cleaning materials and technologies, with reference to conservation sites located in Bologna, Italy. After identifying the most used cleaning materials and technologies, the time necessary for achieving an equal cleaning effectiveness was selected as functional unit and the LCA analysis was carried out, along with a quantitative evaluation of some other key aspects of the different methods (workers’ health, acoustic impact and waste produced in the building site). The results highlight that the different technologies involve remarkably different environmental impacts, but that in some cases their impact could be easily reduced by substituting some secondary materials in the cleaning process, without affecting the effectiveness of cleaning. The results also show that the methods involving the lowest environmental impact are not necessarily the best ones in terms of safety and waste production in the building site
Analisi LCA comparativa di adesivi per posa ceramica tradizionali e innovativi
No full textL’obiettivo dello studio è la valutazione comparativa del danno ambientale dovuto al ciclo di vita di adesivo per posa ceramica ottenuto dalla lavorazione di scarto cotto e aggregati naturali al fine di valutare dal punto di vista ambientale, il processo industriale necessario per ottenere le materie prime secondarie e confrontarlo con la produzione di aggregati naturali. L’analisi ha evidenziato che il processo di produzione della sabbia mediante riciclo è più impattante a causa del consumo energetico richiesto per riprocessare gli scarti. Lo studio pone inoltre le basi per un nuovo approccio alla gestione del rifiuto. Nell’ambito dello studio, infatti, il rifiuto viene considerato non solo come tale ma come coprodotto della produzione di un prodotto che esce dal sistema che lo genera per produrre materiali secondari. Con questo criterio si attribuisce a chi usa il secondario (LCA contiguo) una parte del danno dovuto alla produzione del rifiuto (processo LCA che genera il coprodotto)
Sustainability analysis through life cycle assessment: over the only environmental impacts. Application at the case study: integrated waste management system in Baalbek (Lebanon)
No full textSustainable development has as primary aim to improve environmental, economic and social conditions, both at local territorial and global level. The sustainability represents a complex concept often confused with the environmental impact reduction. A complete sustainability investigation depends on the environmental impacts and also on its economic and social consequences, both in absolute and relative terms.
The research shows as the method of life cycle assessment (LCA) can be used to do a complete sustainability analysis of a case study.
Specifically the study has the objective to evaluate, through the LCA approach, the environmental impacts of an integrated waste management plant projected in Lebanon and also to estimate economic and social effects related to this plant. The plant was dimensioned to serve the population of Union of Commons of Baalbek. It consists of a sorting and composting plants, an anaerobic digester plant and a sanitary landfill located in the Caza of Baalbek.
The environmental analysis was conducted using the SimaPro 8.2 software and the IMPACT 2002+ evaluation method. The inventory analysis has been conducted using primary and secondary data whenever available. The remaining data have been obtained from the EcoInvent database v.2 - v.3. In the analysis have been included (i) the municipal solid waste collection, (ii) the waste separation (with different sorting process technologies to divide recyclable items, compostable material and not-differentiated inert waste) (iii) the pretreatment of recyclable material, (iv) anaerobic digestion of organic material, (v) composting of the remainder organic material and of the anaerobic digestion product, (vi) disposal in a landfill of not recyclable material, (vii) the use of anaerobic digestion biogas to produce electricity by cogeneration.
An economic quantification, differentiating incoming, investments and operation costs of the plant has been done. Finally, the social effects with an estimation of benefits deriving from the introduction of a new waste management system in a developing country have been considered. Three specific indicators to demonstrate (i) the occupation (jobs related to the waste management system), (ii) the function of the system (the management of municipal solid waste) and (iii) the management mode choice (that is representative of the combination introduced by the system of alternative waste treatment) have been used
COMPARATIVE LIFE CYCLE ASSESSMENT OF INNOVATIVE AND TRADITIONAL ADHESIVES FOR THE LAYING OF CERAMIC TILES
No full textThe mission of sustainable development exerted the pressure demanding for the adoption of proper methods to protect the environment across all industries, including construction. Waste management is considered an urgent problem that needs to be addressed by identifying favorable solutions to minimize its environmental burden. Recycling is one of the strategies inducing the minimization of waste directed to landfill sites, by promoting their reuse, along with reducing demand for new raw materials. In the construction field, the request of aggregates generates a strong impact on the territory because of a mining activity, which can be planned and regulated with great difficulty. It is more and more relevant to focus on the qualitative and quantitative evaluation of contribution that the secondary aggregates, obtained by valorization of waste, can lead to the fulfillment of the needs of the construction industry. For this reason it is necessary to assess, in terms of a technical and environmental point of view, the industrial processes to obtain the secondary raw materials available for use and to compare them with the production of natural aggregates by mining activity. This paper aims to compare the environmental impact due to the production of adhesive for the laying of baked clay, obtained by the manufacturing of baked waste and natural aggregates, by paying attention on the main environmental burdens which characterize the production of natural and recycled aggregates. As a result, the recycling process leads to an increase in environmental impact compared to the production of natural sand as the energy consumption in the recycling process reduces the benefits of saving raw materials. However, the ceramic waste recycling leads to a decrease of the overall potential damage of 44% compared to landfilling
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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