Analiza efikasnosti rada sistema toplotne pumpe za hlađenje svežeg mleka sa predhlađenjem i mogućnošću iskorišćenja otpadne toplote za dogrevanje potrošne vode

Contemporary livestock production implies production of highly valuable, biologically and chemically safe products. Dairy production has no exception too. On the contrary, the quality standards for raw milk are highly increased. The quality of raw milk is defined by its chemical composition and the total count of microorganisms in control volume. In this paper we discussed the performance of advanced system for heat recovery from raw milk and its application in the process of preheating and preparation of process water. The energy and exergy efficiency of one of such systems were analyzed. It was determined that the implementation of the system for milk cooling with precooling and using the waste heat for preheating process water could achieve significant savings. The system consists of 'milk to water' heat pump, pre-cooler for milk cooling and storage tank for process water with heating possibility. Values of exergy efficiency of each component of system and potential improving of components performances were determined. Also, the exergy efficiency and potential improvement of complete system were determined.Savremena stočarska proizvodnja podrazumeva proizvodnju visoko vrednih, biološki i hemijski bezbednih proizvoda. Proizvodnja mleka nije izuzetak, naprotiv, norme kvaliteta sirovog mleka su sve strožije. Kvalitet sirovog mleka je određen njegovim hemijskim sastavom i ukupnom brojnošću mikroorganizama u kontrolnoj zapremini. U ovom radu biće razmatran rad naprednog sistema za rekuperaciju toplote iz svežeg mleka koja se potom koristi u procesu dogrevanja i pripreme potrošne vode. Primenom sistema za hlađenje mleka sa predhlađenjem i korišćenjem dobijene toplote za zagrevanje potrošne vode mogu se postići značajne uštede. U radu je analizirana energetska i eksergetska efikasnost rada jednog ovakvog sistema. Sistem se sastoji od toplotne pumpe 'mleko-voda', predhladnjaka za hlađenje svežeg mleka i skladišnika potrošne tople vode sa mogućnošću njenog dogrevanja. Ustanovljene su veličine eksergetske efikasnosti komponenata sistema i potencijal poboljšanja svake od komponenata u sistemu. Takođe, ustanovljena je eksergetska efikasnost celokupnog sistema i potencijal njegovogpoboljšanja

Uticaj različitih režima rada krovnih ventilatora na raspored koncentracija prašine u objektu za vezano držanje krava

Analysis of roof cooling fans function in several working regimes is presented. The main goal of the research was to define the influence of fan working regime on airborne dust particles concentration. Dust concentration is significant microclimate parameter in the livestock building. Increased dust concentration affects the animal and workers health. During the different fan speeds, the measurements were conducted in characteristic building sections. There were 48 measuring points selected, in 4 height levels, which totally covered the room. Comparative analysis of air flow velocities and dust concentrations showed that this fan setup may give satisfactory results. Certain working regimes were recommended for use, and the third speed step was emphasized.U radu je prikazana analiza rada krovnih ventilatora u više režima rada, sa ciljem da se utvrdi uticaj intenziteta rada ventilatora na koncentraciju pojedinih frakcija prašine. Koncentracija prašine je bitan pokazatelj kvaliteta mikroklime u proizvodnim objektima. Prisustvo povećanih vrednost koncentracije prašine nepovoljno se odražava na zdravlje životinja ali i zaposlenih. Ispitivan je uticaj ventilatora pri različitim režimima rada (različitim brzinama rotora), pri čemu su merenja vršena u karakterističnim zonama objekta. Merenje temperature i relativne vlažnosti vazduha je izvršeno u 48 mernih tačaka, na 4 nivoa merenja, čime je objekat u potpunosti pokriven. Analiza rezultata merenja je otkrila kakvi su efekti rada ventilatora u pojedinim zonama objekta. Uporednom analizom sa brzinama strujanja vazduha u pojedinim režimima rada ventilatora, izveden je zaključak da ovakva postavka ventilatora može imati zadovoljavajuće efekte. Preporuka je da se koriste određeni režimi rada, prevashodno treći stepen brzine rotora

Predlog poboljšanja ambijentalnih uslova u objektima za tov svinja na farmi 'Vizelj'

State of ambient conditions in the finishing pigs fattening unit is analyzed in the paper. Efficiency and productivity of this pig production phase significantly influence the production results of the whole pig farm. Based on the present conditions analysis, this paper should suggest improvements of microclimate conditions in the researched confinements. Existing ambient conditions was monitored in 3 measurement points, disposed in the zones of the fans operation and between them. Measurement results showed the critical zone with the very low ventilation effect. Over the whole room, increased values of airborn pollutants were noticed. According to the results analysis, possible procedures for improvements were considered. Suggested solution includes installation of additional equipment and minor constructional adaptations. Combined effects of the existing and the additional equipment, along with its possibilities for fine regulation, should significantly improve the existing conditions.U radu je analizirano stanje ambijentalnih uslova u objektu za tov svinja. Karakteristično za ove objekte je da se u njima nalaze životinje u završnoj, finalnoj fazi lanca proizvodnje svinjskog mesa. Od produktivnosti i ekonomske efikasnosti ove faze proizvodnje, često zavisi uspeh poslovanja cele farme svinja. Cilj rada je da na osnovu detaljne analize postojećeg stanja mikroklime u objektu, a u skladu sa dimenzijama, brojnim stanjem životinja u objektu i rasporeda i efikasnosti postojeće opreme, razmotre potencijalna rešenja poboljšanja stanja mikroklime u objektu. Postojeće stanje ambijenta snimano je u tri merne tačke, raspoređene po objektu tako da se obuhvate zone uticaja ventilatora, ali i zone u kojima je efekat rada ventilatora slabije izražen. Rezultati merenja ukazuju na postojanje problematične zone u objektu u kojoj je efekat provetravanja slab. Međutim, u celom objektu su uočene povećane vrednosti pojedinih zagađivača stajskog vazduha. Na osnovu analize rezultata merenja razmotreni su i potencijalni načini za poboljšanje stanja ambijenta. Predloženo rešenje podrazumeva ugradnju dodatne opreme i manje adaptacije objekta. Kombinovanjem pozitivnih strana postojeće opreme, sa prednostima dodatne opreme uz široke mogućnosti regulacije, može se očekivati značajan efekat poboljšanja stanja mikroklime u posmatranom objektu

Efficiency analisys of the heat pump system for raw milk cooling with precooler and possibility for waste heat recovery through sanitary water heating

Contemporary livestock production implies production of highly valuable, biologically and chemically safe products. Dairy pro duction has no exception too. On the contrary, the quality standards for raw milk are highly increased. The quality of raw milk is de fined by its chemical composition and the total count of microorganisms in control volume. In this paper we discussed the perform ance of advanced system for heat recovery from raw milk and its application in the process of preheating and preparation of process water. The energy and exergy efficiency of one of such systems were analyzed. It was determined that the implementation of the sys tem for milk cooling with precooling and using the waste heat for preheating process water could achieve significant savings. The system consists of "milk to water" heat pump, pre-cooler for milk cooling and storage tank for process water with heating possibility. Values of exergy efficiency of each component of system and potential improving of components performances were determined. Also, the exergy efficiency and potential improvement of complete system were determine

Mogućnosti poboljšanja efekata rada ventilacionog sistema u odeljenjima prasilište i odgajalište na farmi svinja 'Farkaždin'

Analysis of ventilation systems efficiency in farrowing room and nursery is presented in this paper. Those rooms are selected because of the most sensitive categories in pig production cycle. From this reason, these farm confinements should be carefully analyzed and, if possible, additionally equipped and specially adopted. Based on the present conditions analysis, this paper should suggest improvements of microclimate conditions in the researched confinements. Existing microclimate conditions are monitored in the piglets breath zone, in 12 measuring points, and the zones that are in front and between the fans, as well. Results of the existing conditions analysis emphasized the inefficiency of the present ventilation systems. Especially low effect is achieved in removal of harmful gasses and airborn dust particles. Along with the defined problems, possible solutions are suggested. The solutions included installation of additional ventilation equipment. Combined effects of the existing and the additional equipment, along with its possibilities for fine regulation, should significantly improve the existing conditions.U radu je prikazana analiza rada ventilacionih sistema u odeljenjima prasilišta i odgajališta. Ova odeljenja karakteristična su po tome što se u njima drže najosetljivije kategorije u svinjarskoj proizvodnji. Upravo stoga, ovim odeljenjima treba posvetiti pažnju, i ukoliko postoje mogućnosti i opravdanost uvođenja dodatnih uređaja i adaptacije objekata, iste treba razmotriti i uvesti u praksu. Cilj rada je da se na osnovu analize postojećeg stanja, veličine odeljenja i rasporeda bokseva, kao i rasporeda i broja ventilatora, formira predlog poboljšanja mikroklimatskih parametara u odeljenjima. Postojeće stanje mikroklime snimano je u zoni disanja životinja, u 12 mernih tačaka, pri čemu se vodilo računa da se obuhvati zona uticaja ventilatora, kao i delovi odeljenja gde je njihov efekat manje izražen. Analiza postojećeg stanja mikroklime otkrila je da su efekti rada postojećih sistema ventilacije nedovoljni. Pogotovo je slab efekat iznošenja gasovitih produkata i čestica prašine. Uz analizu, na osnovu uočenih problema, dati su i predlozi za prevazilaženje postojećih problema. Predložena rešenja podrazumevaju ugradnju dodatne ventilacione opreme. Kombinovanjem efekata rada postojeće opreme, sa dodatnom opremom, a pogotovo širokim mogućnostima njene regulacije, može se očekivati značajno poboljšanje postojećeg stanja

Дводимензионални модел стационарног провођења топлоте кроз чврсти говеђи стајњак у току процеса компостирања

U ovom radu je analiziran proces proizvodnje komposta i toplote koja se razvija egzotermnim hemijskim procesima tokom kompostiranja čvrstog govećeg stajnjaka.Aeracija komposta izvedena je na otovrenom platou, korišćenjem odgovarajuće mašine za negu stajnjaka. Na izlazu iz mašine za aeraciju komposta formira se prizma. Temperature u proizvoljnom poprečnom preseku prizme nalazile su se u opsegu od 30-74o C i njihove vrednosti su približno ujednačene i u podužnom pravcu u kome se mašina kreće. Razvijen je dvodimenzionalni numerički model stacionarnog provođenja toplote u proizvoljnom poprečnom preseku prizme. Modelom je obuhvaćen uticaj okoline na procese prostiranja toplote kroz kompost, uticaj termomehaničkih osobina materijala, uticaj nehomogenosti materijala na temperaturno polje. Izvršeno je poređenje rezultata merenja sa modeliranim rezultatima, pri čemu je dobijeno zadovoljavajuće poklapanje

Тechnical review on the applications of ultrasound in agricultural systems

Ultrasonics is new science that is being intensively developed in recent years. Sound velocity is a valuable engineering tool and non-destructive, non-invasive, non-intrusive technique of measurement. The various effects of ultrasound were discussed and outlined in a context of different uses to accelerate or support agricultural production processes like: vibrational and heating effects, cavitational effects, speeding up biochemical processes, mutagenic effects, etc. Special attention was paid on crystallization and separation processes in operational engineering. This paper presents a review of ultrasonic wave application in agricultural production and modern agricultural systems

Potential of production and utilization of heat energy obtained in a process of solid cattle manure composting

The analysis of producing of heat from the compost production process, with goal to determine a rough sketch of the potential use of heat that develops in the process of composting is presented in this paper. Production of compost from solid cattle manure in bright plateau, using appropriate equipment is considered. Conductet temperature measurments revealed the temperature increase in the mass of up to 75 ° C,with a fairly stable temperature regime. A model for the analysis, elemental prism was adopted. In the conducted analysis, certain approximations and simplifications were adopted. This is done because of that in this step only a rough estimate of the potential of heat pro duction is expected. Results from the analysis show that the observed process deserves a more detailed approach, both in experimental work and in completing the analysis of the factors that influence this process

Uticaj različitih muznih sistema na kvalitet mleka u toku muže krava

If the procedures of preparation for milking and finishing operations are conducted correctly, then it can be expected to produce top-quality milk. It is, therefore, necessary to know the basis of physiology of milk secretion, possible sources of contamination and handling procedures with milk after the milking. One of the essential conditions for reducing clinical and subclinical udder diseases and top-quality milk production (somatic cells count ≤ 400000/ml, the total number of microorganisms ≤100000/ml) is milking procedure that involves stimulating and hygienic procedures of udder preparation, milking process, after milking procedures and hygiene of milking equipment. The subject of this study was to determine the influence of preparatory procedures for milking, as well as the milking with different types of milking equipments on hygienic and bacteriological safety of raw milk on family farms.Ukoliko se postupci pripreme za mužu, muža i završne operacije, izvode pravilno, onda se može dobiti mleko vrhunskog kvaliteta. Zato je neophodno poznavanje osnova fiziologije lučenja mleka, mogućih izvora kontaminacije i postupaka sa mlekom posle muže. Jedan od bitnih uslova da se smanje kliničke i subkliničke bolesti vimena i proizvede mleko ekstra klase (broj somatskih ćelija ≤ 400000/ml, ukupan broj mikroorganizama ≤ 100000/ml) jeste procedura muže koja obuhvata stimulativne i higijenske procedure pripreme vimena, tok muže, proceduru nakon muže i higijenu aparata za mužu. Predmet istraživanja je bio da se utvrdi uticaj pripremnih postupaka muže, kao i sam proces muže različitim tipovima muznih uređaja na higijensku i bakteriološku ispravnost sirovog mleka na porodičnim farmama

Komparativna analiza različitih strategija za kontrolu klasične svinjske kuge upotrebom Monte Carlo simulacije

Several different strategies for control and eradication of Classical Swine Fever (CSF) were compared using a Monte Carlo method-based simulation model. The control strategy analyzed in this paper, in addition to other CSF control measures, includes application of biosecurity measures on pig farms and rural backyard holdings. Elements of the control strategy are based on applicable regulations and include the simulation of detection of the disease, setting up the protected and surveillance zones, standstill of pig movements and restricted movement of animals, vehicles, equipment, and people with strong control measures in protection and surveillance zones, euthanasia of susceptible pigs, protective vaccination of pigs, compensation etc. During the simulation, different output parameters were compared such as: duration of epizootic of a disease, number of affected holdings and animals, direct costs such as those for dead or culled animals, costs of surveillance, disposal of infectious materials, cleaning and disinfection. Depopulation of affected animals with early diagnostics and vaccination in protection and surveillance zone proved to be the most effective measures to stop spreading and eradication of the disease. However, during the simulation, systematic implementation of biosecurity measures in all pig production clusters demonstrated to be appropriate strategy for sustainable control of CSF and setting up a stable epizootiological situation.Nekoliko različitih strategija za kontrolu i iskorenjivanje klasične kuge svinja je upoređivano primenom modela simulacije zasnovanog na Monte Karlo metodi. Kontrolne strategije koje su obrađivane u ovom radu, pored opštih i posebnih mera suzbijanja KKS, uključuju i različite nivoe primenjenih biosigurnosnih mera na komercijalnim, porodičnim farmama i seoskim gazdinstvima na kojima se ga je svinje. Mere neškodljivog uništavanja obolelih životinja i životinja koje su bile u kontaktu sa obolelim životinjama, uspostavljanje zaštitnih zona pod nadzorom, kontrola i zaustavljanje prometa životinja i mehaničkih vektora (vozila i ljudi) unutar zona, rano otkrivanje bolesti i mera vakcinacije su bile uključene u simulaciju. Izlazni parametri kao što su: vreme trajanja epizootije, broj zaraženih gazdinstava i životinja, broj uništenih životinja, troškovi nadzora i direktne štete nastale zbog pojavljivanja bolesti s upoređivani tokom simulacije. Vakcinacija, neškodljivo uklanjanje obolelih životinja i rana dijagnostika su se pokazale kao najefektivnije mere zaustavljanja širenja i iskorenjivanja bolesti. Međutim, kao mera dugoročne strategije kontrole KKS i uspostavljanja stabilne epizootiološke situacije, tokom simulacije pokazala se mera planskog i sistematskog podizanja biosigurnosnih mera u svim klasterima proizvodnje svinja (komercijalne farme, porodične farme tipa A, porodične farme tipa B i seoska gazdinstva)