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Hybrid systems for wastewater treatment in the framework of circular economy : coupling biological and membrane technologies for a sustainable water cycle
Get PDFThe increasing water demand coupled to the depletion of natural water sources has raised the need to investigate and develop in wastewater treatment and reuse. Even more, the application of circular economy principies to water cycle has highlighted the need to see wastewater as a source of water and resources. Therefore, hybridization of already developed technologies can help achieve circular economy goals. Moreover, these hybrid systems that take the best of each technology are capable to gain to the limitations of current conventional treatments. Thus, in this thesis, different hybrid systems have been developed and tested (at bench and pilot scales) for wastewater treatment, both urban and industrial.
On one hand, three upflow anaerobic sludge blanket (UASB) reactors with different configurations: flocculent biomass, flocculent
biomass and membrane solids separation and granular biomass and membrane solids separation (UASB-AnMBR), were operated to compare start-up, solids hydrolysis and effluent quality. The challenges of this work were both the low temperature and the low COD content. A really quick start-up was observed for the three reactors and was attributed to the previous acclimation of the seed sludge. The UASB configurations with membrane retained the solids in the reactor increasing solids hydrolysis efficiency. Moreover, flocculent biomass promoted slightly higher hydrolysis than granular one. Therefore, a configuration based on flocculent UASB-AnMBR was appropriate for the treatment of urban wastewater with low COD content at 10°C. '
On the other hand, a single-stage AnMBR for the treatment of cheese whey and its co-digestion with cattle slurry was investigated with the aim of potentially recovering water and energy. High COD removal (91% ± 7%) was achieved with a biogas production of 0.2-0.9 m3 biogas/kg COD removed. Therefore, high energy recovery could be obtained when using this process with a mean value of 2.4 kWh/kg COD removed. Although energy recovery was directly validated, severallimitations were detected regarding water reuse. Those limitations comprised high salt concentration in the permeate, which should be removed prior to its reuse.
Moreover, petrochemical wastewater pre-treatment was optimised with the final objective of water recycling. lt consisted in a coagulation-flocculation (CF) step followed by a moving bed biofilm reactor (MBBR) aimed to decrease suspended solids (SS) and organic content. In this case, only the first part of the hybrid system was optimised, membrane units were not included in this work. CF tests showed a decrease in wastewater turbidity but no significant DOC removal. Wastewater was then treated by MBBR. In MBBR, high sCOD removal efficiency (80-90%) was maintained. The MBBR proved to be also effective when treating raw wastewater as well as when feed wastewater effluent proportions were changed. The obtained results showed that MBBR was a suitable technology for petrochemical wastewater pre-treatment.
Finally, a novel treatment strategy for landfillleachate aimed to decrease its environmental impact was studied. The system consisted in a membrane bioreactor (MBR) pre-treatment aimed to remove COD, N and SS. lt was followed by a combined reverse osmosis-electrodialysis reversa! (RO-EDR) treatment aimed to remove salts and decrease brine volume. MBR decreased inorganic carbon by 92 ± 8% and achieved N removal of 85%. RO achieved a recovery of 84% and rejections of above 95%. EDR unit treating RO brine achieved a recovery of 67%. Thus, average recovery of the whole system was above 90%. lt is important to highlight that end-of-life RO regenerated membranes were used in this study. This fact, together with the low volume of brine (<10%) helped decrease the environmental impact of leachate treatment.
Hence, this thesis was conducted from an applied research approach, aimed to reduce the gap between basic technology development and industrial implementation.La creixent demanda d'aigua i l'esgotament de les fonts naturals ha generat la necessitat d'investigar i desenvolupar nous tractaments d'aigua així com la seva reutilització. L'aplicació dels principis de l'economia circular al cicle de l'aigua ha posat de manifest la necessitat de percebre les aigües residuals com a font d'aigua i recursos. Així dones, la hibridació de tecnologies ja desenvolupades pot ajudar a complir els objectius de l'economia circular. A més, aquests sistemes híbrids són capaços de superar les limitacions deis tractaments convencionals. Així dones , en aquesta tesi, s'han desenvolupat i provat diferents sistemes híbrids (a escala de banc de proves i pilot) per al tractament d'aigües residuals urbanes i industrials. D'una banda, s'han operat tres configuracions de reactors UASB (Upflow Anaerobic Sludge Blanket) per comparar la posada en marxa, la hidrólisi dels sòlids i qualitat de l'efluent. Aquestes configuracions eren: biomassa flocular, biomassa flocular amb separació per membrana i biomassa granular amb separació per membrana (UASB-AnMBR). Els reptes d'aquest treball han estat tant la baixa temperatura com el baix contingut en DQO. La posada en marxa ha estat molt ràpida per als tres reactors, atribuïda a l'aclimatació prèvia dels fangs . Els resultats mostren que una configuració basada en UASB-AnMBR amb biomassa flocular ha estat adequada peral tractament d'aigües residuals urbanes amb baix contingut en DQO a 10°C. D'altra banda, s'ha investigat un AnMBR per al tractament de xerigot i la seva codigestió amb purí amb l'objectiu de recuperar aigua i energia . S'ha aconseguit una elevada eliminació de DQO (91% ± 7%) amb una producció de biogàs de 0,2 a 0,9 m3 de biogàs/kg de DQO eliminada. Per tant, es calcula que es podria obtenir una elevada recuperació d'energia amb un valor mitja de 2,4 kW/kg de DQO eliminada. Tot i que s'ha validat directament la recuperació d'energia, s'han detectat diverses limitacions en relació amb la reutilització de l'aigua. Aquestes limitacions inclouen una elevada concentració de sal en el permeat, que caldria eliminar abans de la seva reutilització. A més, s'ha optimitzat el pretractament pera aigües residuals petroquímiques amb l'objectiu de reciclar l'aigua. Aquest ha consistit en una coagulació-floculació (CF) seguida d'un MBBR (Moving Bed Biofilm Reactor) per tal de disminuir els sòlids en suspensió (SS) i el contingut orgànic. En aquest cas, només s'ha optimitzat la primera part del sistema híbrid ja que no s'han inclòs les etapes de membrana en aquest treball. Les proves de CF han mostrat una disminució de la terbolesa de les aigües residuals sense eliminació significativa de DQO. Aquest efluent s'ha tractat per MBBR. A I'MBBR s'ha mantingut una elevada eficiència d'eliminació de DQOs (80-90%). Els resultats obtinguts mostren que el MBBR és una tecnologia adequada per al pretractament de les aigües residuals petroquímiques. Finalment, s'ha estudiat una nova estratègia de tractament de lixiviats d'abocador per disminuir el seu impacte ambiental. El sistema s'ha basat en un pretractament amb bioreactor de membrana (MBR) pera l'eliminació de DQO, Ni SS seguit d'un tractament combinat d'osmosi inversa-electrodiàlisi reversible (01-EDR) pera l'eliminació de sals i disminució el volum de salmorra . L'MBR ha disminuït el carboni inorgànic en un 92 ± 8% i ha aconseguit una eliminació de N del 85%. Gracies a les etapes d'OI i EDR, la recuperació mitjana de tot el sistema ha superat el 90%. És important destacar que en aquest estudi s'han utilitzat membranes regenerades d'OI al final de la seva vida útil. Aquest fet, juntament amb el baix volum de salmorra {<10%) ha contribuït a disminuir !'impacte ambiental del tractament de lixiviats. Per tant, aquesta tesi s'ha dut a terme des d'un enfoc de recerca aplicada, amb l'objectiu de reduir la bretxa entre el desenvolupament tecnològic basic i la implementació industrialDOCTORAT EN ENGINYERIA AMBIENTAL (Pla 2012
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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