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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Human excreta treatment technologies : prerequisites, constraints and performance /

Niwagaba, Charles, January 2007 (has links) (PDF)
Licentiatavhandling (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2007. / Härtill 3 uppsatser.
32

Behavior and Control of Mercury in Sewage Sludge Thermal Treatment Process / 下水汚泥熱処理プロセスにおける水銀の挙動と排出制御

Cheng, Yingchao 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22430号 / 工博第4691号 / 新制||工||1732(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 米田 稔, 准教授 大下 和徹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
33

Koncepce termického zpracování odpadů z komunální sféry / Conception of Thermal Treatment of Waste from Municipal Sector

Frýba, Lukáš January 2019 (has links)
European Union and states of European Union legislation are updated according new information about the composition and content of danger compounds in the sewage sludge from municipal waste water treatment plants. It has the effect on using of modern technologies for disposal in sewage sludge treatment. These methods are designed for sewage sludge hygienization, amount reduction, material transformation for next using or sludge incineration for energy production and utilization. The thesis is focuses on the effective thermal treatment of sewage sludge from waste water treatment plants. An important part of the line for sewage sludge incineration is pre-treatment and reduction of water content. The water content reducing is a high energy consumption process which is helpfull to use waste heat from energy plants where it would be loosed without using.
34

Control of Volatile Organic Compound (VOC) Air Pollutants

Hunter, Paige Holt 16 June 2000 (has links)
A variety of methods exist to remove volatile organic compound (VOC) air pollutants from contaminated gas streams. As regulatory and public opinion pressures increase, companies are searching for more effective methods to control these emissions. This document is intended as a guide to help determine if existing systems are adequate and to provide additional information to improve the efficiency of the systems. It explores conventional methods of controlling VOC emissions, as well as innovative technologies including membrane separation, plasma destruction, and ozone catalytic oxidation. The conventional technologies covered include condensation, adsorption, absorption (or scrubbing), thermal incineration, flaring, catalytic incineration, and biofiltration. Each chapter includes a description of the technology, a discussion of the types of systems available, notes on the design of the system, economic estimates, an explanation of potential problems, and a list of considerations for installation and maintenance concerns. The final chapter is dedicated to the preparation and characterization of metal catalysts which were developed to improve the reaction rate of VOCs using ozone as an oxidant. / Ph. D.
35

Climate Change Implications for Health-Care Waste Incineration Trends during Emergency Situations

Raila, Emilia Mmbando 01 January 2015 (has links)
Healthcare waste (HCW) incineration practices in the global South countries are among the major sources of black carbon (BC) emissions or smoke. This study analyzes HCW incineration trends during emergency situations and smoke from HCW incineration processes in Haiti. The study was prompted by the current arguments about the climate change and the growing health effects associated with BC emissions. The conceptual framework was based on both adverse health effects from BC emissions exposure and climate change potential of BC emissions. Therefore, the goal was to determine whether cardboard HCW sharps containers emit lower BC emissions to the atmosphere during the incineration process, relative to the plastic sharps containers, and the pattern of emergency HCW incineration before and after the 2010 earthquake and cholera emergencies in Haiti. This was an observational study conducted with secondary data on HCW incinerated weights from January 2009 to December 2013 and primary data on average smoke densities. Linear regression analysis of the pattern of HCW incinerated weights revealed a relatively linear pattern (R2 = 0.164) with fluctuating scenarios (peak sharp rise in 2012). Independent samples t-tests demonstrated significantly lower smoke emission during the incineration processes of cardboard sharps HCW containers as compared to plastic containers (95 % CI, p = 0.003). Implications for positive social change include provision of quantitative evidence of the benefits of cardboard sharps HCW containers in reducing smoke during incineration activities, potential data for policy formulation, suggestions for review of existing HCW guidelines, and additional research on potential health impacts of emergency HCW disposal and BC emissions.
36

Η ένταξη της καύσης στην ολοκληρωμένη διαχείριση των αστικών στερεών αποβλήτων της περιφέρειας Δυτικής Ελλάδας

Μουγκογιάννης, Νικόλαος 08 May 2012 (has links)
Στην παρούσα εργασία διερευνάται η καύση των Αστικών Στερεών Αποβλήτων (ΑΣΑ) και η δυνατότητα δημιουργίας Εγκατάστασης Καύσης των ΑΣΑ (ΕΚΑΣΑ) στην Περιφέρεια Δυτικής Ελλάδας (ΠΔΕ). Στο 1ο κεφάλαιο δίνεται η περιγραφή της διαχείρισης των ΑΣΑ σε χώρες του εξωτερικού. Εδώ δίνονται στοιχεία για πρωτοπόρες χώρες στην καύση των ΑΣΑ και η γενικότερη διαχείριση των ΑΣΑ τους. Διερευνάται αρχικά η κατάσταση στην Ευρώπη, στον υπόλοιπο κόσμο και στις αναπτυσσόμενες χώρες. Η καύση των ΑΣΑ είναι μια μέθοδος που χρησιμοποιείται ευρέως σε μεγάλες, βόρειες και πλούσιες χώρες της Ευρώπης. Αυτή η τεχνολογία επεξεργασίας των ΑΣΑ σε πολλές χώρες φτάνει έως και το 50% (π.χ. Ελβετία και Δανία) της συνολικής διαχείρισης των ΑΣΑ. Τέλος παρουσιάζεται η πρόσφατη οδηγία του Ευρωπαϊκού Κοινοβουλίου 2008/98/EΚ, η οποία ταξινομεί τους τρόπους διαχείρισης των ΑΣΑ και κατατάσσει την καύση των ΑΣΑ με ενεργειακή ανάκτηση πάνω από την εφαρμοζόμενη στην Ελλάδα ταφή των ΑΣΑ και κάτω από την ανακύκλωση. Επίσης καθορίζεται πότε η καύση των ΑΣΑ θεωρείται ανάκτηση και όχι διάθεση, σύμφωνα με τον συντελεστή R1 που εξετάζεται στο 5ο κεφάλαιο. Τέλος παρουσιάζεται και η οδηγία του Ευρωπαϊκού Κοινοβουλίου 99/31/ΕΚ η οποία προβλέπει την σταδιακή μείωση των βιοαποδομήσιμων αστικών αποβλήτων που οδηγούνται στους ΧΥΤΑ, κάτι που μπορεί να γίνει με την καύση. Στο 2ο κεφάλαιο δίνεται μια σύντομη παρουσίαση της ΠΔΕ. Γίνεται μια ανασκόπηση του πληθυσμού, του τουρισμού, των οικονομικών και των μεταφορών της ΠΔΕ. Επίσης δίνονται στοιχεία για τα φυσικά χαρακτηριστικά της ΠΔΕ (κυρίως ύδατα), του κλίματος και των προστατευόμενων περιοχών της ΠΔΕ. Στο 3ο κεφάλαιο γίνεται πρόβλεψη της ποσότητας και της ποιοτικής σύστασης των ΑΣΑ που παράγονται στην ΠΔΕ για το έτος έναρξης λειτουργίας της ΕΚΑΣΑ, το 2020. Σύμφωνα με στοιχεία των απογραφών του 1991 και του 2001 και τον εποχικό πληθυσμό του 2009 που πάρθηκε από την Ελληνική Στατιστική Αρχή, (ΕΛ.ΣΤΑΤ) υπολογίζεται ο ισοδύναμος πληθυσμός της ΠΔΕ σε περίπου 850.000 κατοίκους. Έπειτα λαμβάνεται ο ρυθμός παραγωγής ΑΣΑ ανά κάτοικο και ημέρα από τον Παναγιωτακόπουλο, [Παναγιωτακόπουλος, 2008] και υπολογίζεται η ετήσια συνολική παραγωγή των ΑΣΑ για την ΠΔΕ το 2020 σε περίπου 372.000 τόνους. Ακολούθως λαμβάνεται η ποιοτική σύσταση των ΑΣΑ από τον Οικονομόπουλο, [Οικονομόπουλος, 2009] καθώς και ότι το 10% της συνολικά παραγόμενης ποσότητας ΑΣΑ ανακυκλώνεται το 2020. Τέλος αφού αφαιρεθεί η ποσότητα των ΑΣΑ που ανακυκλώνεται εκτιμάται η συνολική ποσότητα των ΑΣΑ που δύναται να καεί σε περίπου 335.000 τόνους. Στο 4ο κεφάλαιο επιλέγεται η θέση της ΕΚΑΣΑ στην Βιομηχανική Περιοχή της Πάτρας (ΒΙΠΕ). Η ΕΚΑΣΑ είναι βιομηχανική μονάδα, παράγει ατμό για άλλες βιομηχανίες και είναι σε κοντινή απόσταση από τον κύριο παραγωγό ΑΣΑ της ΠΔΕ, τον Δήμο Πατρέων. Παρουσιάζονται οι Σταθμοί Μεταφόρτωσης Απορριμμάτων (ΣΜΑ) και οι διαφορετικές μέθοδοι σχεδιασμού τους. Με τους ΣΜΑ θεωρείται ότι μπορεί να επιτευχθεί οικονομικότερη μεταφορά και μεταφόρτωση των ΑΣΑ στην ΕΚΑΣΑ σε σχέση με την μεταφορά με απορριμματοφόρα (Α/Φ). Εδώ ελέγχεται η οικονομία που επιτυγχάνουν ανά Καλλικρατικό Δήμο. Ο ΣΜΑ τοποθετείται στο κέντρο του Καλλικρατικού Δήμου και οι Πηγές Παραγωγής ΑΣΑ (ΠΠΑΣΑ) θεωρούνται οι Καποδιστριακοί Δήμοι με ποσότητες που εκτιμώνται στο 3ο κεφάλαιο. Στοιχεία κόστους λαμβάνονται μερικώς από εμπειρικά στοιχεία των Περιφερειών της Δυτικής Μακεδονίας και της Ανατολικής Μακεδονίας και Θράκης καθώς και από βιβλιογραφικές αναφορές. Συμπεραίνεται ότι η χρήση των ΣΜΑ ρίχνει το μεταφορικό κόστος των ΑΣΑ, στους περισσότερους Δήμους της ΠΔΕ, με ελάχιστες εξαιρέσεις. Ελέγχονται επίσης μέθοδοι επιχειρησιακής έρευνας και εκτιμάται αδυναμία εφαρμογής τους αφού προϋποθέτουν σαφείς θέσεις χωροθέτησης των ΣΜΑ, κάτι που είναι δύσκολο και πολύπλοκο να εκτιμηθεί. Στο 5ο κεφάλαιο αρχικά παρουσιάζονται οι τεχνικές καύσης των ΑΣΑ και επιλέγεται ως τεχνική καύσης των ΑΣΑ της ΠΔΕ η μαζική καύση των ΑΣΑ σε εστία με εσχάρες. Η τεχνική αυτή είναι η πιο διαδεδομένη και με πιο αξιόπιστα στοιχεία. Έπειτα εκτιμάται η Κατώτατη Θερμογόνος Δύναμη (ΚΘΔ) των ΑΣΑ βάσει των μετρήσεων του Καραγιαννίδη, [Karagiannidis et al., 2010] για την θερμική αξία των ΑΣΑ της Θεσσαλονίκης και της εκτιμώμενης σύστασης των ΑΣΑ από τον Οικονομόπουλο. Η ΚΘΔ εκτιμάται σε 10,885 Mj/kg ΑΣΑ, τιμή ίση και μεγαλύτερη από αυτή που έχουν τα ΑΣΑ σε μεγάλες ευρωπαϊκές χώρες. Ακόμα λαμβάνεται ένα απλό θερμικό δίκτυο για την ΕΚΑΣΑ από το βιβλίο του Κ.Χ. Λέφα, [Λέφας, 1982] για παραγωγή ηλεκτρικής και θερμικής ενέργειας και εκτιμώνται οι βαθμοί απόδοσης της ΕΚΑΣΑ. Τέλος εξετάζεται αν η ΕΚΑΣΑ μπορεί να θεωρηθεί διαχείριση ανάκτησης (ισοδύναμη με την μηχανική και βιολογική επεξεργασία) ή διάθεσης (ισοδύναμη των ΧΥΤΑ) των ΑΣΑ, βάσει του συντελεστή R1 που εισάγει η οδηγία 2008/98/EΚ και στατιστικών στοιχείων της Ευρωπαϊκής Συνομοσπονδίας των ΕΚΑΣΑ (CEWEP). Η ΕΚΑΣΑ πετυχαίνει R1 μεγαλύτερο του 0,65 για παραγωγή μόνο ηλεκτρικής ενέργειας και για συμπαραγωγή ηλεκτρικής και θερμικής ενέργειας. Στο 6ο κεφάλαιο αρχικά παρουσιάζονται οι αέριες εκπομπές, τα υγρά απόβλητα και τα στερεά υπολείμματα των ΕΚΑΣΑ. Οι αέριες εκπομπές των ΕΚΑΣΑ, με χρήση σύγχρονων συσκευών ελέγχου των αέριων εκπομπών, παραμένουν αρκετά κάτω από την όρια που θέτει η οδηγία 2000/76/ΕΚ. Οι ΕΚΑΣΑ παράγουν τέφρα που είναι αδρανές υλικό και διατίθεται με ασφάλεια σε ΧΥΤΥ. Η ιπτάμενη τέφρα που παράγεται μετά από επεξεργασία σταθεροποιείται και έπειτα μπορεί να διατεθεί σε ΧΥΤΥ. Δίνονται στοιχεία για την μέση σύσταση των παραπάνω καθώς και τα όρια που θέτει η Ευρωπαϊκή Ένωση (ΕΕ) και η Αμερικανική Υπηρεσία Περιβάλλοντος (EPA). Τέλος παρουσιάζονται τα συστήματα ελέγχου των αέριων εκπομπών. Στο 7ο κεφάλαιο εκτιμάται το κόστος κατασκευής της ΕΚΑΣΑ και τα αναμενόμενα έσοδα που μπορούν να προκύψουν από την πώληση της παραγόμενης ηλεκτρικής και θερμικής ενέργειας. Το κόστος εκτιμάται από την βιβλιογραφία. Ένα ποσοστό εσόδων μπορούν να υπολογιστούν βάση της επιδότησης που δίνει ο ν.3851/2010 για το βιοαποδομήσιμο κλάσμα των ΑΣΑ που θεωρείται βιομάζα και η ηλεκτρική ενέργεια που παράγεται από αυτό θεωρείται ανανεώσιμη (ΑΠΕ). Τα υπόλοιπα έσοδα που προκύπτουν από την παραγωγή ηλεκτρικής ενέργειας από το μη βιοαποδομήσιμο κλάσμα δεν δύναται να τιμολογηθούν. Επίσης τα έσοδα από την πώληση θερμότητας, θεωρείται ότι καλύπτουν την κατασκευή συστήματος τηλεθέρμανσης ως ανταποδοτικό όφελος για την τοπική κοινωνία που φιλοξενεί την ΕΚΑΣΑ. Το κόστος της ΕΚΑΣΑ συγκρίνεται με το παρόν κόστος της απόθεσης των ΑΣΑ σε ΧΥΤΑ και προκύπτει μικρότερο. Το κόστος του ΧΥΤΑ εκτιμάται σε 8-35 €/τόνο ΑΣΑ, ενώ της ΕΚΑΣΑ σε 10,5 – 26,125 €/τόνο ΑΣΑ. Καταλήγοντας, σε αυτή την εργασία, προτείνεται για πρώτη φορά η καύση των ΑΣΑ στην ΠΔΕ. Σύμφωνα με την σύγχρονη τεχνολογία, η καύση είναι μια οικονομική λύση με ελάχιστες περιβαλλοντικές επιπτώσεις, οι οποίες περιορίζονται σε τοπικό επίπεδο, σε αντίθεση με την διάθεση σε ΧΥΤΑ, όπου οι επιπτώσεις είναι αφενός τοπικές και αφ’ετέρου παγκόσμιες και ο έλεγχος των εκπομπών περιορισμένος. Η μεγάλη μείωση στον όγκο των ΑΣΑ (90%) που επιτυγχάνεται, ελαχιστοποιεί τις απαιτήσεις μεγάλων χώρων διάθεσης και αμβλύνει τις κοινωνικές και περιβαλλοντικές επιπτώσεις. Η δυνατότητα ανάκτησης ηλεκτρικής και θερμικής ενέργειας, καθώς και μετάλλων, καθιστούν βιώσιμη την καύση των ΑΣΑ. Τέλος, σημαντικό είναι και το γεγονός ότι η ενέργεια αυτή σε μεγάλο ποσοστό της (55,4%) θεωρείται ΑΠΕ. Επομένως, η ένταξη της καύσης των ΑΣΑ στην ολοκληρωμένη διαχείριση τους θα προσφέρει στην επίτευξη του στόχου της Ελλάδας για 40% ηλεκτρική ενέργεια από ΑΠΕ μέχρι το 2020 (ν.3851/2010). / This paper studies the combustion of municipal solid waste (MSW) and the possible creation of MSW incineration plant (each) in Western Greece (RWG). In the first chapter is to describe the management of MSW in foreign countries. Here are figures for leading countries in the combustion of MSW and the overall management of the MSW. Investigated initially the situation in Europe, the world and developing countries. The combustion of MSW is a method widely used in large and wealthy northern countries of Europe. This technology for processing MSW in many countries at up to 50% (eg Switzerland and Denmark) the overall management of MSW. Finally presents the recent directive of the European Parliament 2008/98/EK, which classifies the management of MSW and ranks MSW incineration with energy recovery over the applied in Greece burial of MSW and bottom of recycling. It also determines when the combustion of MSW is recovery and not disposal, in accordance with the R1 factor considered in chapter 5. Finally presented and Directive 99/31/EC of the European Parliament which provides for the gradual reduction of biodegradable municipal waste going to landfills, which can be done by burning. In the second chapter gives a brief introduction of the EDP. Is an overview of population, tourism, finance and transport of the EDP. Also given of the physical characteristics of the PDE (mainly water), climate and protected areas of the EDP. In the third chapter is predicting the quantity and qualitative composition of MSW produced in the EDP for the initial year of operation of each, in 2020. According to data from the censuses of 1991 and 2001 and the seasonal population of 2009 was taken from the Greek Statistical Authority (EL.STAT) estimated the equivalent population of EDP of 850,000 inhabitants. Then take the production rate of MSW per inhabitant and day by Panagiotakopoulos [Panagiotakopoulos, 2008] and calculate the total annual production of MSW in the EDP in 2020 to around 372,000 tonnes. Then take the qualitative composition of MSW by Economopoulos, [Economopoulos, 2009] and that 10% of the total produced quantity of MSW recycled in 2020. Finally, subtracting the amount of MSW recycled estimated the total amount of MSW that can be burned to about 335,000 tonnes. In the fourth chapter the chosen position EKAS the Industrial Area of ​​Patras (Industrial Zone). Each being the plant produces steam for other industries and is walking distance from the main MSW producer of the EDP, the Municipality of Patras. Presented the Waste Transfer Station (WTS) and different methods of design. With STDs considered to be achievable economical transport and transfer of MSW to EKAS in relation to transport garbage (M / F). This controlled the economy achieved by Kallikrates City. The STD is placed in the center Kallikaratous Municipality and the sources of MSW (PPASA) are the Kapodistrian Municipalities with quantities estimated in the third chapter. Cost data obtained in part by empirical evidence of the Regions of Western Macedonia and Eastern Macedonia and Thrace as well as bibliographic references. It is concluded that the use of STD throws the transport costs of MSW in most municipalities of EDP, with few exceptions. Also controlled methods of operational research and assess their inapplicability as clear positions require siting of STDs, which are complex and difficult to assess. In the fifth chapter presents the first technical combustion of MSW and selected as a technique of combustion of MSW PIP mass burning of MSW fireplace with grills. This technique is the most widespread and most reliable data. After assessing the Low Calorific Value (KTHD) of MSW based on measurements of Karagiannidis, [Karagiannidis et al., 2010] for the heat value of MSW in Thessaloniki and the estimated composition of MSW by Economopoulos. The KTHD estimated at 10,885 Mj / kg MSW, a price equal to and greater than that which the SMR in major European countries. Even taking a simple thermal network for EKAS from the book of CE Lefas [Lefas, 1982] to produce electricity and thermal energy and the estimated yield of each. Finally considering whether EKAS can be considered administration recovery (equivalent to the mechanical and biological treatment) or disposal (equivalent of landfills) of MSW, the rate R1 introduced by the Directive 2008/98/EK and statistics of the European Confederation of EKAS (CEWEP). The R1 gets EKAS than 0.65 for only electrical energy and combined heat and power. In the sixth chapter first presents the air emissions, effluents and solid residues each. Gaseous emissions from each, using modern equipment to control air emissions remain well below the limits set in Directive 2000/76/EC. The EKAS produce ash is an inert material and safely disposed of in landfills. The fly ash produced after treatment stabilizes and then can be placed in landfills. Given of the average composition of the above and the limits set by the European Union (EU) and the U.S. Environmental Agency (EPA). Finally put the control of gaseous emissions. In chapter 7 the estimated construction cost of each and the expected revenue can be derived from the sale of electricity and thermal energy. The cost is estimated from the literature. A percentage of revenue can be calculated based on the subsidy given by the n.3851/2010 the biodegradable fraction of MSW is biomass and electricity produced from it is renewable (RES). The remaining proceeds from the production of electricity from non-biodegradable fraction can not be billed. Also, revenue from the sale of heat, are deemed to cover the construction of district heating system as a contributory benefit for the local community hosts each. The cost of EKAS compared with the present cost of disposal of MSW in landfills and less apparent. The cost of landfill is estimated at 8-35 € / tonne of MSW, while the EKAS at 10,5 - 26,125 € / tonne of MSW. In conclusion, this work proposed for the first time the combustion of MSW in the EDP. According to modern technology, combustion is a cost effective solution with minimal environmental impacts, which are limited locally, as opposed to disposal in landfills, where the impact is both local and global, and on the other hand the control of emissions limited. The large decrease in the volume of MSW (90%) achieved, minimizing the requirements of large disposal sites and mitigate the social and environmental impacts. The recoverability of electricity and thermal energy and metals, making sustainable combustion of MSW. Finally, important is the fact that energy is a large percentage of (55.4%) is considered renewable. Therefore, the inclusion of the combustion of MSW in the integrated management will provide the objective of Greece's 40% electricity from renewables by 2020 (n.3851/2010).
37

Transfer těžkých kovů při spalování odpadů / Heavy Metals Transfer during Waste Incineration

Karásek, René January 2011 (has links)
The municipal solid waste (MSW) is a heterogeneous material that consists mainly of organic and mineral substances, metals and water. After thermal treatment this waste redistributes into individual incineration products. This also holds for the metals contained in the waste. This thesis deals with the behaviour of heavy metals and their compounds during the incineration process. Determining the percentage content of heavy metals from the waste entering the process of thermal utilization is practically impossible. The principal aim is to determine the amount of each heavy metal in the MSW from the incineration products. The opening sections of the thesis deal with waste, options of incineration, flue gas cleaning processes and also with the problems of the heavy metals in the environment. The next section introduces recent developments, what possibilities there are for determining the heavy metals in the waste and methods of data evaluation. The experimental part of the thesis introduces of a four-day measuring process that was conducted at the MSW incineration plant SAKO, Inc. The samples of the individual products of incineration were taken and after the laboratory analysis the results for the selected heavy metals were processed. The results include statistical data analysis.
38

Pyrolysis of chlorinated hydrocarbons using induction heating.

Pillay, Kruben. January 2004 (has links)
Chemical and allied industries produce significant quantities of chlorinated wastes each year. Thermal treatnent of these chlorinated wastes has a long and controversial history. The most common and contentious method of waste destruction is incineration. Although waste incinerators are designed to provide greater control over the combustion process, toxic products are inevitably formed from incomplete combustion and released in stack gases and other residues. The most notable group belonging to the products of incomplete combustion (PICs) are dioxins and furans. The fact that oxygen is an integral part of the molecular structure of dioxins and furans suggests that the formation of these particular PICs may be reduced or avoided by minimizing or completely excluding oxygen from thermal waste treatment. Pyrolysis using induction heating is a relatively new technology that has shown much promise from the initial work performed by Pillay (2001). This research was an extension of that study, and investigated equipment and process optimization as well as macroscopic modeling of different systems. The objective of this study was to establish the technology of pyrolysis using induction heating as a competitive alternative to existing waste destruction systems. The novel approach of pyrolysing compounds using induction heating was demonstrated by destroying chlorinated aliphatic, aromatic and a mixture of these compounds. These experiments were conducted at atmospheric pressure in a tubular laminar flow reactor (5.2cm I.D) under a thermally transparent argon atmosphere. In this system heat was generated in an embedded graphite tube using induction heating. Thermal degradation occurred through the bombardment of the compounds by the photons emitted from the heated graphite tube. The compounds were pyrolysed at temperatures ranging from 330°C to 1000°C and at mean residence times from 0.47s to 2.47s. In addition to these process variables the effects of reactant concentration and additives were investigated The major species formed from this thermal treatment were solid carbon black and gaseous hydrogen chloride. Destruction efficiencies (DE) of the order of 99.9999% (six nines) and greater were obtained for the different feed mixtures at their respective operating conditions. A minimum DE of six nines adequately satisfies the regulation set by the Environmental Protection Agency (EPA) for successful waste destruction. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2004.
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SYSTEM IDENTIFICATION OF A WASTE-FIRED CFB BOILER : Using Principal Component Analysis (PCA) and Partial Least Squares Regression modeling (PLS-R)

Hassling, Andreas, Flink, Simon January 2017 (has links)
Heat and electricity production along with waste management are two modern day challenges for society. One of the possible solution to both of them is the incineration of household waste to produce heat and electricity. Incineration is a waste-to-energy treatment process, which can reduce the need for landfills and save the use of more valuable fuels, thereby conserving natural resources. This report/paper investigates the performance and emissions of a municipal solid waste (MSW) fueled industrial boiler by performing a system identification analysis using Principle Component Analysis (PCA) and Partial Least Squares Regression (PLS-R) modeling. The boiler is located in Västerås, Sweden and has a maximum capacity of 167MW. It produces heat and electricity for the city of Västerås and is operated by Mälarenergi AB. A dataset containing 148 different boilers variables, measured with a one hour interval over 2 years, was used for the system identification analysis. The dataset was visually inspected to remove obvious outliers before beginning the analysis using a multivariate data analysis software called The Unscrambler X (Version 10.3, CAMO Software, Norway). Correlations found using PCA was taken in account during the PLSR modelling where models were created for one response each. Some variables had an unexpected impact on the models while others were fully logical regarding combustion theory. Results found during the system analysis process are regarded as reliable. Any errors may be due to outlier data points and model inadequacies.
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Análise econômica e ambiental do processamento da vinhaça com aproveitamento energético / Economic and environmental analysis of vinasse processing with energy recovery.

Poveda, Manuel Moreno Ruiz 21 January 2015 (has links)
A vinhaça é o principal resíduo da produção de etanol de cana-de-açúcar e, no Brasil, são gerados aproximadamente 250 milhões de m3 de vinhaça por safra. Atualmente, este efluente é usado para fertirrigação dos canaviais em sua forma in natura, ou seja, sem tratamento prévio. Devido à sua grande quantidade de matéria orgânica e de sais, a disposição inadequada no meio ambiente pode ser causa tanto de impactos no solo e na água, como de emissões de gases de efeito estufa. O objetivo geral deste estudo é comparar diferentes alternativas de processamento para o aproveitamento energético da vinhaça, em busca daquela com maior desenvolvimento tecnológico, que mitigue os possíveis impactos ambientais da fertirrigação com vinhaça in natura e que esteja associada a um menor custo. Para esta finalidade, foram configurados cinco cenários que representam as tecnologias mais estudadas atualmente. Como cenário de referência, foi estabelecido a fertirrigação com vinhaça in natura e, como suas alternativas, consideraram-se: 1.concentração, 2.biodigestão e 3.incineração com produção de energia elétrica, bem como 4.combinação da biodigestão com a concentração e com o uso veicular do biogás. Uma vez feita a avaliação, concluiu-se que todas as alternativas melhoram o desempenho ambiental da gestão do resíduo e, ao mesmo tempo, permitem o aproveitamento e a economia de energia. Entretanto, o sistema de concentração é a única opção que se mostra viável economicamente na situação atual. Para ser atrativo o investimento nas demais tecnologias, seria necessária a introdução de medidas que premiem monetariamente os serviços ambientais, tais como a mitigação de emissões de gases de efeito estufa, a redução do consumo de água e a produção de energia a partir de fontes renováveis. A combinação da biodigestão com a posterior concentração pode ser a opção que reúne o maior número de vantagens com respeito ao cenário de referência. Com esta combinação, o biogás produzido é utilizado para suprir o consumo de energia do processamento e para substituir o diesel na frota usada na produção da cana-de-açúcar. Relativo aos impactos ambientais, esta configuração tecnológica diminui o volume da vinhaça, facilita sua distribuição a longas distâncias, evita a concentração de nutrientes no entorno das usinas, elimina o odor da decomposição da vinhaça e as emissões de metano, possibilita a reutilização da água e permite a substituição de combustíveis fósseis. Além disso, a vinhaça biodigerida e concentrada tem boas qualidades como fertilizante. / The vinasse is the main residue of ethanol production from sugarcane. In Brazil, around 250 million m3 of vinasse are generated per harvesting season. Currently, this effluent is used in natura, ie, without previous treatment, for sugarcane fertirrigation. Due to its large amount of organic matter and salts, inadequate disposal in the environment may cause impacts on soil and water, as well as greenhouse gases emissions. This study aims to compare different alternative process for vinasse energy recovery, searching which ones have the highest technological development nowadays, mitigate the possible environmental impacts of fertirrigation using in nature vinasse and involve the lowest cost. For this purpose, five scenarios were configured, representing the most widely studied technologies. As the baseline scenario it was established fertirrigation using in nature vinasse and, as alternatives scenarios, the following ones were considered: 1. concentration, 2. digestion and 3. incineration with electricity generation, and 4. digestion plus concentration with vehicular use of biogas. It was concluded that all the alternatives improve the environmental performance of vinasse management since they also allow energy recovery and savings. However, only vinasse concentration system is economically feasible nowadays. For the other technologies to become an attractive investment, it would be necessary to include an economic valuation of environmental services, such as greenhouse gas emissions mitigation, reduction of water consumption and renewable energy production. The combination of digestion and subsequent concentration may be the option that brings together the largest number of advantages comparing to the baseline scenario. In this solution, the biogas produced is used to supply the process power consumption and to replace diesel in the fleet used for sugarcane production. Regarding the environmental impacts, this technology configuration reduces vinasse`s volume, facilitates its distribution to long distances, prevents nutrient concentration around mills, eliminates decomposition odor and methane emissions, enables water reuse and allows fossil fuels replacement. Furthermore, digested and concentrated vinasse has good qualities as fertilizer.

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