Μαθηματική προσομοίωση συστήματος επεξεργασίας στραγγιδίων μέσω νιτρωδοποίησης - απονιτρωδοποίησης

Ανδριανόπουλος, Αλέξανδρος; Andrianopoulos, Alexandros

dc.contributor.author	Ανδριανόπουλος, Αλέξανδρος	el
dc.contributor.author	Andrianopoulos, Alexandros	en
dc.date.accessioned	2016-03-10T09:04:32Z
dc.date.available	2016-03-10T09:04:32Z
dc.date.issued	2016-03-10
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/42134
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.11282
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/gr/	*
dc.subject	Νιτρωδοποίηση	el
dc.subject	Στραγγίδια	el
dc.subject	Απονιτρωδοποίηση	el
dc.subject	Προσομοίωση	el
dc.subject	Μερική νιτροποίηση	el
dc.subject	Nitritation	en
dc.subject	Shortcut nitrification	en
dc.subject	Denitritation	en
dc.subject	SBR	en
dc.subject	Liquor	en
dc.title	Μαθηματική προσομοίωση συστήματος επεξεργασίας στραγγιδίων μέσω νιτρωδοποίησης - απονιτρωδοποίησης	el
dc.title	Mathematical simulation of liquor wastewater treatment system through nitritation - denitritation	en
heal.type	bachelorThesis
heal.classification	Sanitary engineering	en
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh85117279
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2015-11-04
heal.abstract	Στις μέρες μας, η συνεχώς αυξανόμενη ευαισθητοποίηση σε σχέση με τα περιβαλλοντικά ζητήματα, έχει καταστήσει αναγκαία την υιοθέτηση αυστηρών κριτηρίων λειτουργίας και εκροής στις μονάδες επεξεργασίας υγρών αποβλήτων. Στόχος της παρούσας εργασίας είναι η διερεύνηση του φαινομένου της μερικής νιτροποίησης ή αλλιώς νιτρωδοποίησης, και της απονιτρωδοποίησης, σε αντιδραστήρα εναλλασσόμενης λειτουργίας (SBR), χρησιμοποιώντας μαθηματική προσομοίωση. Για το σκοπό αυτό έγινε επέκταση του μαθηματικού μοντέλου ASM1 της IAWQ, ώστε να περιγράφονται αναλυτικά και τα δύο στάδια της διαδικασίας της νιτροποίησης. Στη συνέχεια έγινε προσπάθεια να αναχαιτιστεί η ανάπτυξη των βακτηρίων που οξειδώνουν τα νιτρώδη (ΝΟΒ) και να ευνοηθεί η ανάπτυξη αυτών που οξειδώνουν το αμμωνιακό άζωτο (ΑΟΒ). Αυτό κατέστει δυνατόν μέσω ενός υπομοντέλου αναχαίτισης που σχετίζεται με την ελεύθερη αμμωνία, όπου σε ορισμένες συγκεντρώσεις, ενεργεί ως ανασταλτικός παράγοντας στην ανάπτυξη των ΝΟΒ βακτηρίων. Λόγω του ανταγωνισμού μεταξύ ΑΟΒ και ΝΟΒ βακτηρίων, η αναχαίτιση των ΝΟΒ, είναι ζωτικής σημασίας για την επιτυχία της διαδικασίας της νιτρωδοποίησης. Η εφαρμογή του μοντέλου, ρυθμίστηκε και επαληθεύτηκε με βάση πειραματικά αποτελέσματα από εργαστηριακής κλίμακας σύστημα. Η ρύθμιση έγινε με τέτοιο τρόπο ώστε τα αποτελέσματα των εφαρμογών του προγράμματος, να προσεγγίζουν με πολύ μεγάλη ακρίβεια τα πειραματικά αποτελέσματα.	el
heal.abstract	Nowadays, the increasing awareness on environmental issues, has necessitated the adoption of stringent operational and discharge criteria in wastewater treatment plants. Since there is a constant demand for more and more economical and sustainable solutions to the operation of these systems, have been developed mathematical models that are valuable tools in their effort of optimization. The objective of this study is to investigate the phenomenon of partial nitrification or otherwise nitritation, and denitritation, in Sequence Batch Reactor (SBR), using mathematical simulation. For this purpose, an expansion of the mathematical model ASM1 of IAWQ was developed, in order to be described minutely both steps of the process of nitrification. Then, an attempt was carried out to wash out the growth of bacteria that oxidize nitrite (NOB) and to favor the growth of these who oxidize the ammonia nitrogen (AOB). This has become possible through sub model of interception, associated with the free ammonia, which in certain concentrations, acts as inhibitor of the growth of the NOBs. Because of the competition between AOBs end NOB, the inhibition of the NOB is vital for the success of nitritation. The simulation program that has been developed, gives the user a wide range of choices, as all the parameters of the model are variable. It also gives the user the opportunity to select between different numbers of operation cycles, different conditions that prevail in the reactor, to determine the duration of each step of the process, to regulate the supply of dissolved oxygen, the volume of the reactor, the daily flow etc. The application of the model was calibrated and verified on the basis of experimental results from laboratory scale systems. The calibration was such that the results of the application are very accurate compared with the experimental results. This became the basic scenario, and the various analyzes that were carried out, were based on it. It is understood that by verifying the results, the simulation program, gives reliable results that can help the design or the optimization of an SBR system that performs nitritation and denitritation. In applications made, was studied the effect of various parameters of the model and the SBR system, the effluent quality and the required amount of dissolved oxygen and external carbon source, with which the system is powered. These applications were divided into three groups, of which the first investigates the effect of various parameters related to the kinetic and stoichiometric parameters of the model, the second category studies the effect of liquor characteristics in the final concentrations of the variables of the model, and the third examines how the operational parameters of SBR system, affect the final results. VIΙI The main conclusions drawn from the above analysis are: − The solids retention time should be sufficient so as not to inhibit the growth of bacteria which oxidize the ammonia nitrogen (AOB). If the growth rate of AOB biomass for any reason is limited, it is necessary to increase the srt to ensure the growth of autotrophic biomass. − The speed of growth of autotrophic biomass that oxidizes nitrite (NOB) has no significant effect on the outflow results, as has been achieved an inhibition of NOBs through sub models of interception. − The conversion rate of AOB autotrophic biomass, has a significant impact on the growth of autotrophic biomass that oxidizes ammonia nitrogen (AOB) and consequently on the final concentration of ammonia nitrogen and nitrite. Typical values correspond to reality is around 0.20 g COD / g N. − The conversion rate of NOB autotrophic biomass, does not have any effect on the growth of autotrophic biomass that oxidizes nitrite nitrogen as it has been washed out, in order to favor to the development of AOB biomass. − Saturation coefficients of the concentration of autotrophic biomass Ki, NH3, AOB and Ki, NH3, NOB have a significant effect on the growth of autotrophic bacteria, as they are the ones who determine in which concentration of free ammonia interception will be occurred. − The concentration of ammonia nitrogen of wastewater liquor is crucial as in one hand determines the concentration of free ammonia through which is achieved the inhibition of NOB biomass, and on the other hand is used for synthesis of new cellular material of heterotrophic and autotrophic biomass. − The concentration of the organic load (COD) imported by the wastewater liquor, affects the growth of heterotrophic biomass but this occurs in very high concentrations of COD and in the majority of cases, this concentration is not available in the liquor. Fractionation incoming COD, due to the small concentration of organic, has no effect on the effluent quality. − The number of operating cycles affects the effluent concentrations and the required quantities of oxygen and external carbon source with which the system has to be supplied. The cycles generally improve the final results but larger amounts of oxygen and carbon are required which increases the operating costs. − It is necessary that the liquor have sufficiently high temperature and alkalinity so as not to inhibit the process of nitritation and denitritation. If this is not possible, it is necessary to make adjustment of pH and temperature in order not to obstruct the proceedings. − The number of operating cycles affects the effluent concentrations and the required quantities of oxygen and external carbon source with which the system has to be supplied. The cycles generally improve the final results but larger amounts of oxygen and carbon are required which increases the operating cost. IX − The amount of external carbon source imported SBR system in the beginning of anoxic phase, has a significant effect both on the process of denitritation, and the concentration of ammonium nitrogen in the effluent. By importing external carbon source, the heterotrophic biomass production is growing, and a large amount of ammonia nitrogen is used for the synthesis of new cell material. − The set point of dissolved oxygen should be determined with caution as inadequate values can lead to inhibition of the growth of heterotrophic and autotrophic bacteria. The increase in srt leads to lower oxygen set point, but this does not imply reduced oxygen consumption.	en
heal.advisorName	Νουτσόπουλος, Κωνσταντίνος	el
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Πολιτικών Μηχανικών. Τομέας Υδατικών Πόρων και Περιβάλλοντος	el
heal.academicPublisherID	ntua
heal.numberOfPages	214 σ.	el
heal.fullTextAvailability	true