Μελέτη υγρών αποβλήτων από την ξήρανση βιοαποβλήτων

Καβαλόπουλος, Μιχάλης

dc.contributor.author	Καβαλόπουλος, Μιχάλης	el
dc.date.accessioned	2020-12-01T07:57:53Z
dc.date.available	2020-12-01T07:57:53Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/52107
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.19805
dc.rights	Default License
dc.subject	Βιοαπόβλητα	el
dc.subject	VFA	el
dc.subject	Ξήρανση	el
dc.subject	Διατροφικά απορρίμματα	el
dc.subject	Ξηραντήρας	el
dc.title	Μελέτη υγρών αποβλήτων από την ξήρανση βιοαποβλήτων	el
dc.contributor.department	Εργαστήριο Γενικής Χημείας	el
heal.type	bachelorThesis
heal.classification	Περιβάλλον	el
heal.language	el
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2020-06-17
heal.abstract	Food waste constitute a very large portion of the municipal solid waste and they occupy a significant percentage of the total volume of the solid waste that end up in landfills. By drying them, their volume can decrease as low as 90%, due to their very high moisture content, and as a result the total volume that they occupy inside the landfill can decrease dramatically. Meanwhile, through the drying procedure food waste are stabilized, resulting in significantly fewer green house gas emissions during their digestion inside the landfill along with the eradication, to a substantial point, of unpleasant odors that are being produced during their decay. Many modern dryers, including various domestic dryers and the GAIA system of decentralized drying, incorporate systems for the condensation of vapors that are being produced during the drying procedure resulting in the creation of a liquid runoff that is much more easily manageable than the gaseous vapors. In this thesis, the condensate of the vapors produced during the drying procedure of various food waste was analyzed concerning their volatile fatty acids (VFA) content and total organic carbon (TOC) content. Volatile fatty acids are chemicals that have multiple applications (food industry, pharmaceutical industry, cosmetics etc.). By measuring their concentration in the aforementioned vapor condensate it is evaluated whether it can be used for the purpose of isolating these useful chemicals. Moreover, by measuring the concentration of the total organic carbon, it was determined what percentage of the total organic load of the vapor condensate is VFA. In this thesis, two different decentralized drying systems were studied: the domestic drying system Smart Cara CS 10 and the GAIA drying system. The samples were all food waste and the ones concerning the first drying system came from a day care in Drosia, Attiki and the ones concerning the second drying system came from the restaurant in National Technical University of Athens. Next, the samples were left in STP temperature for different retention times that varied between 0 to 30 days. This was done in order for the effect of the food waste retention time to the total production of VFA and TOC to be analyzed. Moreover, the effect of the drying time to the total production of VFA and TOC for the GAIA system and for all the samples with the different retention times was analyzed as well. Finally, well established equations for the description of drying curves were fitted to the drying curves of the samples that were studied in this thesis and the R2 was calculated for all of them in order to determine which equation best fits the actual drying curves of the food waste analyzed in this thesis. After analyzing the data it was observed that the quantity of VFA in the vapor condensate is significant and that the production of VFA and TOC is increased along with the increase of the retention time of the samples for both drying systems. Moreover, it became clear that for both drying systems the production of VFA and TOC in relation to the retention time follows a linear fitting model adequately. The production of VFA was considerably higher for the domestic drying system and the growth rate of the VFA in relation to the retention time is substantially higher as well. It was also observed that the TOC production was significantly higher for the GAIA drying system. However, the slope of the fitted lines in the retention time –TOC mass diagrams was the same for both drying systems which shows that the growth rate of the total production of TOC in relation to the retention time is the same for both drying systems. This fact indicates that the production mechanism of organic carbon in the condensate is controlled by reactions that take place during the storage of the samples. After the fitting of 10 drying equations at the origin program, the gauss equation had the best fit as it had an exceptional R2 value for all the experiments and in 8 out of 10 it had the highest value than any other equation. Therefore, it can be concluded that the gauss equation is exceptionally good for the description of the time evolution of the XR moisture in food waste, with the right adjustment of the parameters accordingly. Therefore, it was concluded that the quantity of VFA and TOC in the vapor condensate is significant and can be utilized, the domestic dryer had a significantly higher production of VFA per sample kg than the GAIA dryer, the retention time of the sample increases the production of both VFA and TOC in a way compatible to a linear model and the Gauss equation presents the best fit to the drying curves than all the other aforementioned equations.	el
heal.advisorName	Χαραλάμπους, Αικατερίνη	el
heal.committeeMemberName	Χαραλάμπους, Αικατερίνη	el
heal.committeeMemberName	Παπαδόπουλος, Γιώργος	el
heal.committeeMemberName	Κόλλια, Κωνσταντίνα	el
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Χημικών Μηχανικών. Τομέας Χημικών Επιστημών (I). Εργαστήριο Γενικής Χημείας	el
heal.academicPublisherID	ntua
heal.numberOfPages	120 σ.	el
heal.fullTextAvailability	false