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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.
1

Prefeasibility Study for a Waste-to-EnergyApplication in Gauteng Province, South Africa

Subasinghe, Gayan January 2013 (has links)
Waste-to-Energy concept becomes increasingly popular from the perspectives of the waste management and alternative energy. South Africa, which is a country heavily dependent on the fossil fuel, can explore the opportunities of Waste-to-Energy in order to deal with increasing amount of waste generated while reducing what is deposited at non-engineered landfills, thereby increase the renewable energy share. This prefeasibility study attempts to identify Waste-to-Energy potentials in Gauteng provinceso as to develop a Waste-to-Energy facility under the new renewable Independent Power Producer procurement programme of South Africa. The analysis identifies abundant Wasteto-Energy incineration and landfill gas opportunities linked with municipal solid waste in twomunicipalities. The prefeasibility study further evaluates environmental, socio-economic aspects of Waste-to-Energy initiative. The financial viability of a Waste-to-Energy incineration facility with the Feed-in-Tariff proposed by the government of South Africa isalso detailed analysed.
2

Human excreta treatment technologies : prerequisites, constraints and performance /

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

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).
4

NOx-reducering vid avfallsförbränning / NOx reduction at waste incineration plants

Löfgren, Helena January 2018 (has links)
Avfallsförbränning kan användas för att minska volymen hos avfallet, destruera farligt avfall och utvinna energi för el- och värmeproduktion. Umeå Energis kraftvärmeverk Dåva 1 förbränner hushålls- och verksamhetsavfall. Vid förbränningen bildas bland annat kväveoxider (NOx) vars utsläpp regleras dels av Förordning SFS 2013:253 om förbränning av avfall och dels av Lagen (1990:613) om miljöavgift på utsläpp av kväveoxider (NOx) vid energiproduktion (kväveoxidavgiften). Dåva 1 använder selektiv icke-katalytisk rening (SNCR) med ammoniakinsprutning för att rena rökgaserna från NOx. En del av ammoniaken förblir oreagerad (ammoniakslip) och bidrar troligen till korrosion på den kallare lågtrycksekonomisern nedströms rökgaskanalen. Umeå Energi vill minska sina utsläpp av NOx utan att öka risken för ammoniakrelaterad korrosion av lågtrycksekonomisern. I det här arbetet undersöktes om och hur NOx-bildningen kunde minskas och om det befintliga SNCR-systemet kunde optimeras. Vidare gjordes en utredning om användningen av selektiv katalytisk rening (SCR) på svenska avfallsförbränningsanläggningar samt om och var i Dåva 1 SCR skulle vara fördelaktig att installera. Effektiviteten hos SNCR-systemet testades genom att i perioder stänga av ammoniakdoseringen och logga rökgasinnehållet. Det visade sig vara mycket effektivt (80 %) om det kördes vid rätt temperaturintervall. Men det framkom också att temperaturgränserna för vilken tdoseringsnivå som används troligen kan behöva korrigeras för förbättringar i effektiviteten vid andra temperaturer. Det skulle kunna minska både NOx-utsläpp och ammoniakanvändningen. Användningen av SCR vid svenska avfallsanläggningar undersöktes genom intervjuer. Det visade sig vara bara fem anläggningar och där alla hade placerat katalysatorn i rengasposition, alltså efter elfilter och våt rening. Rökgasinnehållet vid tre olika positioner i Dåva 1 undersöktes för att se om det fanns höga halter av SO2, HCl och stoft, vilka i kombination med ammoniak kan skapa beläggningar som minskar effektiviteten hos en katalysator. Alla positioner låg efter slangfiltren och hade därmed låg stofthalt. Position A låg mellan slangfilter och högtryckseko1 hade den varmaste positionen (205℃) och position B efter ekopaketen (145℃). Position C var efter alla reningssteg i rengaspostion och svalaste positionen (65℃). Variationen hos temperaturerna för de olika positionerna medför en stor skillnad i behovet av att återvärma rökgaserna. Den säkraste positionen, med lägst innehåll av stoft, HCl och SO2 var rengaspositionen, men den krävde istället mest uppvärmning av rökgaserna. Med tanke på att SNCR-systemet visade sig ha förbättringspotential, borde det effektiviseras innan man överväger att installera ett SCR system. / Waste incineration is used to reduce the volume of waste, destruction of hazardous waste and to extract energy in combined heat and power plants (CHP). Umeå Energi’s CHP Dåva 1 incinerates municipal solid waste (MSW) and other hazardous waste. Nitrogen oxides (NOx) are formed in the combustion process. The emission of NOx is regulated in Sweden’s regulation SFS 2013:253 and law 1990:613. Dåva 1 uses selective non-catalytic reduction (SNCR) with ammonia as flue gas treatment, to reduce NOx in the flue gas. Some of the ammonia in the process remains unreacted (ammonia slip) and it probably contributes to corrosion in the colder economizer. Umeå Energi wants to reduce the NOx emissions without increasing the ammonia related corrosion of the economizer. In the present study, the possibility to reduce NOx formation by SNCR optimization was evaluated. Furthermore an investigation on the use of selective catalytic reduction (SCR) in waste incineration plants in Sweden, and whether it is beneficent to install in Dåva 1, was included. The current efficiency of the SNCR system was tested by switching of the ammonia in short periods of time and measuring and logging the flue gas composition. The efficiency (80 %) proved to be very high if operated at the optimal temperature. ButHowever, the test also showed that the temperature limits for the injection levels could be optimized for improved efficiency. Improved efficiency at all temperatures could reduce both NOx emission and ammonia use. The use of SCR in Swedish waste incineration plants was investigated through interviews. It was found that only five plants are equipped with SCR and they were placed in the clean gas position – after electrostatic precipitatorelectric filter and wet scrubber treatment. The contents of the flue gas was examined monitored at three positions at Dåva 1. The content of SO2, HCl and dust were measured, which in combination with ammonia can cause coating with reduces the efficiency of the catalyst. All three positions were located after the textile filters and had low contents of dust. Position A was located between the textile fabric filters and the economizers and was the hottest position with 205℃. Position B was located after the economizers and had the temperature of 145℃. Position C had the cleanest and thereby the safest position for a catalyst, due to its location after all the flue gas treatments, but the temperature was only 65℃ and requires most re-heating of the flue gas. Since the SNCR system proved to have potential to be more efficient, it should be optimized before considering an investment in a SCR system.
5

The Possibility of Energy Recovery from Waste Material in Arges County, Romania

Nordström, Emma, Enochsson, Evelina January 2009 (has links)
<p></p><h1>Abstract</h1><p>Waste disposal is a global problem contributing to the ongoing climate change by large emissions of greenhouse gases. By using waste material as a resource instead of landfilling, the greenhouse gas emissions from landfills are reduced. Waste material can be used for waste incineration with energy recovery, thus decreasing the greenhouse gas emission from energy utilization by changing from fossil fuels to a partly renewable fuel.</p><p>Arges County in Romania has severe problems with its waste material, mainly sewage sludge and waste from households and industries. As a consequence of the Romanian EU accession in 2007, Arges County is obliged to close its landfills for waste in a near future. A reconstruction of the wastewater treatment plant and an improved management of the sewage sludge residue are necessary in order to comply with EU standards. The requirements from the EU regarding waste disposal together with the existence of a district heating network in the residence city Pitesti, makes it interesting to investigate energy recovery from waste material in Arges County.</p><p>Therefore, the goal of the study is to evaluate the possibility to extract energy from co-incineration of the waste material, sewage sludge and waste generated in Arges County. In order to reach this goal, the composition and quantities of the waste material is investigated. A suitable technology for the waste-to-energy (WTE) plant is proposed, based on the data of the waste material as well as on   established WTE technologies and their costs. It is assumed that the WTE plant will be implemented in 2020 and that all the generated waste will be incinerated. Furthermore, an environmental analysis is carried out, which presents the reductions of greenhouse gas emissions with the proposed WTE plant in comparison with the present system; including the management of waste and sludge and the district heating production, which is based on fossil fuels.</p><p>The result shows that the waste material in Arges County has a calorific value of 7.5 MJ per kg, which is suitable for co-incineration of waste and sludge. The suggested WTE plant has the total power of 130 MW, annually recovering 620 and 330 GWh of heat and electric power respectively. The investment cost of the WTE plant is estimated to 226 million euro with a payback time of 8 years. The environmental analysis shows that the proposed system in comparison with the present system will decrease greenhouse gas emissions by 88 percent.</p><p>A WTE plant appears to be a sound investment in Arges County and would sharply reduce the emissions of greenhouse gases in the county. However, some obstacles exist. Waste management is a new field in Romania and currently there are no WTE plants. Furthermore, the data used in this study concerning the quantity and composition of the waste, is uncertain and further studies are necessary before a WTE plant can be established.</p><p> </p>
6

A System Perspective on District Heating and Waste Incineration

Holmgren, Kristina January 2006 (has links)
Energy recovery by waste incineration has a double function as waste treatment method and supplier of electricity and/or heat, thereby linking the systems of energy and waste management. Both systems are undergoing great changes, mainly due to new regulations. Important regulations within waste management in Sweden are a ban on landfill of combustible waste and organic waste, and a tax on landfill of waste. New waste incineration facilities are being built in order to increase capacity to meet these demands. The aim of this thesis is to investigate impacts on Swedish district heating systems of increased use of waste as a fuel in economic and environmental terms, the latter mainly by assessing emissions of carbon dioxide. Of importance is the influence of various policy instruments. To highlight the connection between the energy and waste management systems and how these influence each other is another goal, as well as the function of district heating systems as user of various waste heat supplies. An important assumption for this thesis is a deregulated European electricity market, where the marginal power production in the short term is coal condensing power and in the long term natural gas based power, that affects the conditions for combined heat and power in district heating systems. The method used is case studies of three Swedish municipalities that utilise waste in their district heating systems. In two papers, the scope is broadened from the energy utility perspective by comparing the energy efficiency of energy recovery and material recovery of various fractions, and the effect of including external costs for CO2 as well as SO2, NOx and particles. The ambition is that the results can be part of the decision making process for energy utilities and for policy makers in the energy sector and waste management. It is economically advantageous to use waste as a fuel in the energy sector and regulations in the waste management sector and high taxes on fossil fuels contribute to profitability. Waste incineration plants are base suppliers of heat because they derive revenue from receiving the waste. Economic conditions for waste incineration are altered with the introduction of a tax on incinerated municipal waste. A conflict may arise between combined heat and power production in district heating systems and waste incineration, since the latter can remove the heat sink for other combined heat and power plants with higher efficiencies. Combined heat and power is the main measure to decrease carbon dioxide emissions in district heating systems on the assumption that locally produced electricity replaces electricity in coal condensing plants. It can be difficult to design policy instruments for waste incineration due to some conflicting goals for waste management and energy systems. Comparing the energy efficiency of material recovery and energy recovery is a way to assess the resource efficiency of waste treatment methods. From that perspective, if there is a district heating system which can utilise the heat, biodegradable waste and cardboard should be energy recovered and plastics and paper material recovered. To put costs on environmental effects, so called external costs, is a way to take these effects into regard in traditional economic calculations, but the method has drawbacks, e.g. the limited range of environmental effects included and uncertainties in the monetary valuation of environmental effects.
7

The Possibility of Energy Recovery from Waste Material in Arges County, Romania

Nordström, Emma, Enochsson, Evelina January 2009 (has links)
Abstract Waste disposal is a global problem contributing to the ongoing climate change by large emissions of greenhouse gases. By using waste material as a resource instead of landfilling, the greenhouse gas emissions from landfills are reduced. Waste material can be used for waste incineration with energy recovery, thus decreasing the greenhouse gas emission from energy utilization by changing from fossil fuels to a partly renewable fuel. Arges County in Romania has severe problems with its waste material, mainly sewage sludge and waste from households and industries. As a consequence of the Romanian EU accession in 2007, Arges County is obliged to close its landfills for waste in a near future. A reconstruction of the wastewater treatment plant and an improved management of the sewage sludge residue are necessary in order to comply with EU standards. The requirements from the EU regarding waste disposal together with the existence of a district heating network in the residence city Pitesti, makes it interesting to investigate energy recovery from waste material in Arges County. Therefore, the goal of the study is to evaluate the possibility to extract energy from co-incineration of the waste material, sewage sludge and waste generated in Arges County. In order to reach this goal, the composition and quantities of the waste material is investigated. A suitable technology for the waste-to-energy (WTE) plant is proposed, based on the data of the waste material as well as on   established WTE technologies and their costs. It is assumed that the WTE plant will be implemented in 2020 and that all the generated waste will be incinerated. Furthermore, an environmental analysis is carried out, which presents the reductions of greenhouse gas emissions with the proposed WTE plant in comparison with the present system; including the management of waste and sludge and the district heating production, which is based on fossil fuels. The result shows that the waste material in Arges County has a calorific value of 7.5 MJ per kg, which is suitable for co-incineration of waste and sludge. The suggested WTE plant has the total power of 130 MW, annually recovering 620 and 330 GWh of heat and electric power respectively. The investment cost of the WTE plant is estimated to 226 million euro with a payback time of 8 years. The environmental analysis shows that the proposed system in comparison with the present system will decrease greenhouse gas emissions by 88 percent. A WTE plant appears to be a sound investment in Arges County and would sharply reduce the emissions of greenhouse gases in the county. However, some obstacles exist. Waste management is a new field in Romania and currently there are no WTE plants. Furthermore, the data used in this study concerning the quantity and composition of the waste, is uncertain and further studies are necessary before a WTE plant can be established.
8

Potential for Absorption Cooling Generated from Municipal Solid Waste in Bangkok : A Comparison between Waste Incineration &amp; Biogas Production with Combustion

Hedberg, Erika, Danielsson, Helén January 2010 (has links)
This master’s thesis has been performed in Bangkok, Thailand at the company Eco Design Consultant Co., Ltd. The aim is to investigate the possibilities to generate absorption cooling from municipal solid waste in the Bangkok area. The investigation includes a comparison between waste incineration and biogas production with combustion to see which alternative is preferable. During the investigation, a Swedish perspective has been used. The research for the report mainly consisted of published scientific articles from acknowledged sources as well as information from different Thai authorities. Also, experts within different areas were contacted and interviewed. In order to determine which of the two techniques (waste incineration or biogas production with combustion) that is best suited to generate absorption cooling, a model was designed. This model involved several parameters regarding e.g. plant efficiency, amount of treated waste and internal heat usage. As for the results of the model, three parameters were calculated: the generated cooling, the net electricity generation and the reduced greenhouse emissions. The overall Thai municipal solid waste generation in Thailand is estimated to approximately 15 million tons per year and the majority of the waste ends up at open dumps or landfills. There are only two to three waste incinerators in the country and a few projects with biogas generation from municipal solid waste. The main electricity is today generated from natural gas which makes the majority of the Thai electricity production fossil fuel based. As for absorption cooling, two applications of this technique has been found in Thailand during the research; one at the Naresuan University and one at the Suvarnabhumi airport in Bangkok. The model resulted in that the best alternative to power absorption cooling technique is waste incineration. This alternative has potential to generate 3200 GWh cooling per year and 1100 GWh electricity per year. Also, this alternative resulted in the largest decrease of greenhouse gas emissions, ‐500 000 tons per year. The model also showed that the same amounts of generated cooling and electricity can never be achieved from biogas production with combustion compared to waste incineration. Regardless, waste incineration has an important drawback: the citizens of Thailand seem to oppose further development of waste incineration in the country. The biogas technique seems more approved in Thailand, which benefits this alternative. Due to the high moisture and organic content in the municipal solid waste, a combination between the two waste handling alternatives is suggested. This way, the most energy can be withdrawn from the waste and the volume of disposed waste is minimized. Our overall conclusion is that the absorption cooling technique has great potential in Thailand. There is an increasing power‐ and cooling demand, absorption cooling generated from either or both of the alternatives can satisfy these demands while reducing greenhouse gas emissions. We also believes that the cost for using absorption cooling has to be lower than for the current compression cooling if the new technique is to be implemented further.
9

Treatment technologies for human faeces and urine /

Niwagaba, Charles, January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 5 uppsatser. "Based on joint research training between SLU and Makerere University"
10

Interaktioner mellan svavel, klor och kvicksilver vid avfallsförbränning / Interactions between sulfur, chlorine and mercury in waste incineration

Karolina, Bengtsdotter January 2018 (has links)
Kvicksilver har länge varit ett populärt ämne i flertalet olika produkter på grund utav dess unika egenskaper. Detta har lett till en stor mängd av ämnet går att finna i olika produkter som förbränns i avfallsförbränning. Ämnet är dock väldigt farligt för djur och människor och därav är det av hög prioritet att utsläppen till luft minimeras. Att oxidera kvicksilver från dess elementära form Hg0 till Hg2+ anses vara av största vikt på grund utav att den senare är i högre graden enklare att rena från rökgaserna. Syftet med detta examensarbete var att se om kvicksilver förekommer i högre halt som Hg0 istället för Hg2+ i rökgaserna vid ändrade förhållanden av klor och svavel. Där den förstnämnda är olöslig i vatten och därav svårfångad i dagens reningssystem. Den kan dessutom existera i luft en längre tid och anses vara ett av de mer miljöfarliga ämnena i världen. Examensarbetet har gjorts tillsamman med Umeå Energi AB. För att nå en slutsats har en omfattande litteraturstudie gjorts om ämnet samt mätningar av kvicksilver i rökgaserna från avfallsförbränningsanläggningen Dåva 1 utanför Umeå. Mätningarna utfördes med och utan tillsats av extra svavel i form av bildäck. Analys har även utförts av innehållet i aska ifrån partikelfiltret samt överhettaren för att få en överblick huruvida dess innehåll kan ha gjort någon påverkan.  Mätningarna påvisade att svavel gjorde en påtaglig påverkan på mängden kvicksilver. Vid tillsats av svavel så gavs det indikatorer på att halten av Hg0 ökade. Den mest troliga anledningen till detta tros vara den ökade mängden SO3 som uppmättes i rökgaserna vid det tillfälle då extra svavel var tillsatt. Den ökande mängden kan sedan ha absorberats av de aktiverade kolet som tillsätts innan rökgasreningen, som annars skulle ha absorberat Hg0. Detta är inget slutgiltigt resultat och vidare undersökning är att rekommendera. En annan möjlig teori är att tillsatts av svavel ökar mängden Na2SO4 i filtret. Vilket kan leda till minskad NaCl i filtret som kanske är effektivare vid oxidation av Hg0 än HCl. Mätningarna gav även antydan om att nuvarande reningssystem fungerar bra även vid ökade halter kvicksilver i rågasen. Ökning av kvicksilver i rökgaserna som tros ha orsakats av svaveltillsatsen gav ingen ökning av kvicksilverutsläpp i luft. / For a long time, mercury has been a very popular to use in different kinds of products due to its unique properties. Which has led to a lot of different things containing mercury ends up in waste plants to be incinerated. Mercury are also considered to be one of the most dangerous substances and therefore emissions needs to be kept at minimum. Oxidizing mercury from its form Hg0 to Hg2+ is considered to be extremely important due to the later are easier to remove from the flue gas. The main objective with this thesis was to investigate if mercury would exist more in its elementary form Hg0 than its oxidized state Hg2+ in the flue gas when the ratio between sulfur and chlorine was changed. The former is insoluble in water and therefore difficult to remove from the flue gas with today’s cleaning facility’s. It is also considered one of the more dangerous substances in the world. The project was done in collaboration with Umeå Energi AB. The method that was used to explore this was measuring the mercury content of the flue gas from the waste fired boiler Dåva 1 outside Umeå. The measurement was done with and without extra sulfur added to the fuel in the form of car tires. An additional analysis was done on the ash from the fabricfilter and from the superheater to see if there was something there to give some clarity on why there would be any change in the amount of mercury. The measurement did indeed indicate that sulfur increases the amount of mercury in the flue gas. The main theory to why this has occurred was the increased amount of SO3, which could be found in the flue gas when extra sulphur was added. SO3 is then absorbed by the activated carbon that is added to the flue gas that should have absorbed Hg0 instead. However, this result is not conclusive and further studies needs to be done. Another possible theory to why this has occurred could be that the increase of sulfur could lead to more Na2SO4 in the particle filter. Which could have led to a decrease of NaCl in the filter that could perhaps be a more efficient oxidizing agent of Hg0 than HCl. Another thing that has been revealed is that the cleaning systems that is used today is capable of cleaning mercury from the flue gas even though the added sulfur caused an increase in the amount.

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