Korišćenje otpadne toplote u prehrambenoj industriji primenom kompresorske toplotne pumpe

Abstract

Industrija hrane i pića je značajna industrijska grana u pogledu potrošnje energije. Ona učestvuje sa oko 30% u ukupnoj potrošnji finalne energije u sektoru industrije. Od ukupne količine energije koja se potroši u ovoj industrijskoj grani najviše se troši na konverziju u toplotnu energiju i na procese hlađenja. Prema istraživanjima čak 30% toplotnih tokova u prehrambenoj industriji gubi se na kraju procesa u vidu otpadne toplote, koja je najčešće relativno niske temperature. Utvrđivanjem postojanja izvora otpadne toplote adekvatnog energetskog potencijala i primenom toplotnih pumpi moguće je podići temperaturni nivo na vrednost koja zadovoljava zahteve procesa. Mapiranje izvora otpadne toplote, utvrđivanje energetskog potencijala tih izvora i izbor optimalne snage toplotne pumpe moguće je izvršiti samo sistematskim pristupom i detaljnom analizom postrojenja. U radu je predložena metodologija za mapiranje izvora otpadne toplote u prehrambenoj industriji i utvrđivanje mogućnosti za implementaciju kompresorske mehaničke toplotne pumpe za iskorišćenje otpadne toplote. Predložena metodologija je testirana na studiji slučaja, mlekari, u kojoj se prosečno prerađuje 100 tona/dan mleka, na 7 proizvodnih linija. Primenom razvijene metodologije mapirano je ukupno šest lokacija (izvora) otpadne toplote od kojih su dve pogodne za primenu toplotne pumpe. Nakon izvršene tehno-ekonomske analize utvrđeno je da se ukupna investicija u sistem za prikupljanje i akumuliranje otpadne toplote i nabavku toplotne pumpe isplati za oko 17 meseci. Ukupno smanjenje emisije CO 2 je 680 tona godišnje. The food and beverage industry is a significant global industry in terms of energy consumption. It participates with about 30% in the total energy consumption of the industrial sector. Most of that energy is spent on the conversion into thermal energy and for cooling processes. According to the current findings, 30% of the heat flow in the food industry is lost by the end of a production process. The waste heat obtained hereby has relatively low temperatures. However, it is possible to raise such temperatures to a useful degree, i.e. the one that meets the requirements of a production process, by locating the sources of waste heat with adequate energy potentials and by employing a heat pump. Only systematic approaches and detailed analyses of the plants’ features can result in successful mapping of the sources of waste heat, precise evaluations of their energy potentials, and adequate selection of the optimal power of a heat pump needed for such purposes. This paper proposes a methodology for mapping the sources of waste heat in the food industry and determining the possibility of implementing a compressor mechanical heat pump. The methodology developed here was tested on a dairy that processes 100 tons of milk per day on seven production lines. Six sources of waste heat were identified. Only two are suitable for the implementation of a heat pump. Techno-economic analysis indicates that the total investment into the systems for collecting and accumulating waste heat and the purchase of heat pumps should pay off in about 17 months. The total reduction of CO 2 emission is estimated at 680 tons per year.