Posredni sustav hlađenja jabuka u uvjetima kontrolirane atmosfere

master's thesis

• Title (english): Indirect refrigeration system for apple storage in ultra low oxygen atmosphere
• Author: Domagoj Gregorić
• Mentor: Vladimir Soldo (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-05-17, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Process Energy Engineering

Abstract

U ovom diplomskom radu prikazano je projektiranje rashladnog sustava koji se sastoji od 22 ULO (niskog sadržaja kisika) hladionice za hlađenje jabuka. Razina kisika se održava ubgranicama od 1,5-2,5% dok se količina ugljičnog dioksida nalazi između 1-3%, ovisno o sorti jabuke. Postrojenje se nalazi u kontinentalnoj Hrvatskoj, a sveukupni kapacitet hladnjače iznosi 2800 tona. Sustav je indirektni s radnom tvari R449A u primarnom krugu i mješavinom propilen glikola i vode u sekundarnom krugu. Temperaturni režim glikolne smjese iznosi -1/-4°C. Prikazan je i proračun toplinskih gubitaka hladionica, termodinamičkog procesa, zrakom hlađenog kondenzatora, pločastog isparivača te cjevovoda radne tvari. Na kraju rada izrađena je i shema spajanja i automatske regulacije te dispozicijski crteži rashladnih komora i strojarnice.

Abstract (english)

This graduate thesis will show the process of designing a cooling system that contains 22 ULO (ultra low oxygen) cold rooms for the storage of apples. Depending on the kind of apple inside the cold rooms, the oxygen level is maintained from 1,5-2,5% while the carbon dioxide levels are between 1-3%. The cooling plant is located in continental Croatia, and the total capacity of cold rooms amounts to 2800 tonnes. It is an indirect exchange system with R449A in the primary circuit and a mixture od propylene glycol and water in the secondary circuit. The chosen temperature regime of the glycol mixture is -1/-4°C. The thesis also contains a cold room heat loss calculation, thermodynamic process calculation, plate heat exchanger calculation, air cooled condenser calculation and refrigerant pipeline calculation. At the end of the thesis there is also a connection diagram, diagram of automatic control and a disposition drawing of the cold rooms.

• Keywords: ULO hladnjače; R449A; posredni sustav hlađenja; termodinamički proračun kondenzatora i isparivača
• Keywords (english): ULO cold rooms; R449A; indirect cooling system; thermodynamic calculation of condenser and evaporator
• Language: croatian
• URN:NBN: urn:nbn:hr:235:793484
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-23 00:55:36