Proračun tunela za zamrzavanje ribe

undergraduate thesis

• Title (english): Deep freezing tunnel for fish freezing
• Author: Luka Marin
• Mentor: Vladimir Soldo (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2018-07-12, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Process Energy Engineering

Abstract

Tuneli za duboko zamrzavanje koriste se prvenstveno u prehrambenoj industriji za brzo zamrzavanje hrane. Tim postupkom se održava maksimalna kakvoća hrane nakon odleđivanja. Prilikom “šok smrzavanja” se voda u proizvodu smrzava puno više inicijalnih kristala leda i tako se ne pojavljuju veliki kristali leda koji probijaju opnu stanice u proizvodu. Sami postupak provodi se pri niskim temperaturama isparavanja kako bi se ubrzalo smrzavanje. Ovakve metode se najčešće susreću u većim pogonima gdje je potrebno smrznuti i nekoliko desetaka tona robe u jednoj šarži. Za takve uvjete, za naš slučaj, je potreban isparivač ukupnog učina 80 kW po jednoj hladionici. Sustav je složen sa 3 vijčana kompresora, 1 za svaku hladionicu i vodom hlađenim kondenzatorom za sva 3 sustava. Kako bi sustav bio efikasniji isto tako je praćena dinamika temperature u tunelu i po tome podešavana temperatura isparavanja za maksimalni učin kompresora i isparivača. Korištena radna tvar je R449A ( Opteon XP40 ), koja je napravljena na bazi HFO i HFC radnih tvari. U radu su također obrađeni proračuni isparivača i kondenzatora i na kraju prikazan dispozicijski crtež i shema spajanja.

Abstract (english)

Deep freezing tunnels are used primarily in the food industry for quick freezing of food. This process maintains maximum food quality after defrosting. In a "freezing shock", the product's water freezes with a lot more initial ice crystals, so no large ice crystals that break down the cells membrane in the product appear. The procedure itself is carried out with extremely low evaporation temperatures to accelerate freezing. Such methods are most commonly found in larger plants where several tens of tons of goods in one batch need to be frozen. For such conditions, in our case, a vaporizer requires a total output of 80 kW per one refrigerator. The system is made up of 3 screw compressors, 1 for each freezer and a water-cooled condenser. In order to make the system more efficient, the temperature dynamics in the tunnel were monitored and the evaporation temperature adjusted accordingly for maximum compressor and evaporator performance. The working substance used is R449A (Opteon XP40), based on HFO and HFC groups of working substances. In this paper the evaporator and condenser calculations are also processed, and finally the disposition drawing and the coupling scheme are shown.

• Keywords: tunel; zamrzavanje; riba
• Keywords (english): tunnel; freezing; fish
• Language: croatian
• URN:NBN: urn:nbn:hr:235:685263
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 22:50:41