diplomska naloga
Katarina Lavtar (Author), Violeta Bokan-Bosiljkov (Mentor), Mojca Šraj (Thesis defence commission member), Tanja Ljubič-Mlakar (Co-mentor)

Abstract

Zaradi naravnanosti potrošnikov in ekonomije je odpadkov vse več, kar ima za posledico vse večjo potrebo po ravnanju z njimi. Premišljeno ravnanje jim daje dodatno vrednost in s tem onemogoča, da bi pristali na že tako zapolnjenih deponijah. Reciklaža in ponovna uporaba odpadkov predstavljata vrh hierarhije ravnanja z odpadki in tako ponujata različne možnosti njihove uporabe. Po končani uporabi proizvodov iz odpadkov, ko le ti niso več primerni za reciklažo ali ponovno uporabo, je mnoge še vedno mogoče energijsko izrabiti. Na ta način lahko količino odpadkov zmanjšujemo, hkrati pa zmanjšamo uporabo naravnih virov, tako fosilnih goriv, kot surovin za izdelke. V diplomski nalogi sem preučevala ustreznost plošč iz odpadne embalaže, za sosežig v cementarni. Zanimala me je energijska izraba po končani življenjski dobi le teh. Sosežig odpadkov bi bil lahko brez ustrezne tehnologije škodljiv za okolje, zlasti zaradi emisij v zrak, zato je to področje še posebej regulirano z mrežo različnih predpisov in zakonov. Kot posledica Direktive IED, je Slovenija prenovila Uredbo o vrsti dejavnosti in naprav, ki lahko povzročajo onesnaževanje okolja večjega obsega, ki je stopila v veljavo julija 2015. Na izvedbeni ravni je v skladu z določili Uredbe investitorjem in obstoječim upraviteljem izdano okoljevarstveno dovoljenje, v katerem so zajete mejne vrednosti emisij, mejne količine vhodnih odpadkov in njihova sestava, morebitna vsebnost težkih kovin in halogenih elementov ter tehnološke zahteve. Mogoče je na prvi pogled sosežig odpadkov sporen, vendar je cementarna take vrste industrijski obrat, kjer je zaradi visokih temperatur in več kot petdeset metrov dolge rotacijske peči, omogočen dolg zadrževalni čas dimnih plinov. Ti se gibljejo v nasprotni smeri vhodnih surovin in jih s tem predhodno segrevajo. Na ta način so emisijske vrednosti takšne, kot če bi v cementarni uporabljali samo fosilna goriva. Prav tako ima surovinska moka moč absorpcije določenih žveplovih in halogenih spojin in deluje v ciklonskem izmenjevalniku kot dober filter. Pri tem pa se vse anorganske snovi in težke kovine vgradijo v klinker. Zadnje očiščenje dimnih plinov pred izpustom poteka v vrečastih filtrih. Ti so v referenčnih dokumentih Evropske unije podani kot najboljša razpoložljiva tehnika. Prah iz filtra se vrne nazaj v proces žganja klinkerja, zato je to suh proces, ki ne potrebuje pranja dimnih plinov in s tem ne nastajajo odpadne vode, za katere bi bilo treba dodatno poskrbeti. Cementarna je obrat, ki potrebuje velike količine vhodne energije, da vzdržuje konstantno temperaturo v rotacijski peči, zato je trdno gorivo iz odpadkov kot sekundarni energent dobrodošel v smislu zmanjšanja že tako prevelike porabe fosilnih goriv in hkrati prispeva k bolj ekonomičnemu obratovanju cementarne.

Keywords

gradbeništvo;diplomska naloga;UNI;VOI;trdno alternativno gorivo;kurilna vrednost;energijska izraba;mešani komunalni odpadki;ponovna uporaba;sosežig;ravnanje z odpadki;cementarna;izpusti;okolje;toplogredni plini;onesnaževanje;

Data

Language: Slovenian
Year of publishing:
Typology: 2.11 - Undergraduate Thesis
Organization: UL FGG - Faculty of Civil and Geodetic Engineering
Publisher: [K. Lavtar]
UDC: 502/504:666.9.01(043.2)
COBISS: 8111713 Link will open in a new window
Views: 1557
Downloads: 606
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Other data

Secondary language: English
Secondary title: Boards made of packaging waste as alternative fuel in cement plant
Secondary abstract: Due to economy politics and consumer demand, waste has become a problem. The solution to this problem can be waste valorization. Giving waste a value, maintaining a hierarchy of waste management on all levels, recycling, reusing and processing as energetic use in a cement plant and not dumping waste in overloaded landfills is a way by which not only do we reduce the volume of waste, we also reduce usage of natural sources such as fossil fuels and raw materials. My Graduation thesis is based on how to co-process boards made from packaging waste at the end of their lifespan. Incineration of waste without adequate technology and strict supervision can be harmful to the environment because of air pollution. That is why it is regulated by various legislation acts. In The Republic of Slovenia the fundamental environmental law is Environmental protection act, followed by several different regulation acts. Within the borders of the European Union the most important act is The Industrial emission directive that contains best available techniques reference documents for each field of industry including waste incineration in a cement plant. To comply with the regulation Slovenia adopted a practice of issuing environmental permits. This restricts emissions, limits the waste volume for incineration and deals with the restrictions regarding waste composition in order to eliminate potential heavy metals, halogens and sulphur contents. The incineration of waste in a cement plant may at first seem harmful to the environment, however, the type of industry offers optimal circumstances for such waste treatment. The technology used is a more than fifty meters long rotary klin containing very high temperatures needed for raw materials to be transformed into a cement clinker which renders the technology more than sufficient for the process. This gives a very long retention time for flue gases to stay in high temperature for longer periods needed for burning out. They move in an opposite direction as raw materials entering the rotary klin. This heats up raw materials before entering the burning process. Consequently, this saves energy and also works like a natural filter in a preheating process. The basic nature of raw materials has the ability to absorb acid pollutants, for example sulphur and halogen elements. Before flue gases leave the chimney, they are treated in bag filters. This technique is currently listed as best available technique according to the European Union legislation. Energy consumption in cement plants to maintain high temperatures in rotary klin is enormous. Therefore, the usage of solid recovered fuels with its high calorific values as a secondary energy source contributes not only to the waste management field, but also to reducing fossil fuels overuse thus turning a cement plant operation more economical.
Secondary keywords: graduation thesis;solid recovered fuel;calorific value;energetic use;municipal waste;reuse;waste management incineration;cement plant;emissions;environment;greenhouse gases;pollution;
Type (COBISS): Bachelor thesis/paper
Study programme: 0
Embargo end date (OpenAIRE): 1970-01-01
Thesis comment: Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo
Pages: XV, 56 str.
ID: 10847768