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Namen magistrskega dela je prikazati razvoj tehnološkega procesa proizvodnje prehrambenih kalcijevih fosfatov s poudarkom na sušenju z razprševanjem. V TKI Hrastnik smo edini proizvajalci prehrambenih kalcijevih fosfatov v Sloveniji, prav tako je na razpolago zelo malo literature o proizvodnih postopkih pridobivanja le-teh, zato se pri razvoju tehnološkega postopka opiramo predvsem na zahteve kupcev, ki določajo, kakšen naj bo produkt. Seveda je potrebno upoštevati tudi zahteve, ki jih narekujejo predpisi. Prva faza razvoja tehnološkega procesa prehrambenih kalcijevih fosfatov je potekala v prostorih Kemijskega inštituta v Ljubljani, kjer smo na pilotni napravi testirali in definirali procesne parametre kot so pH vrednost napajalne raztopine (slurry-ja), temperatura reakcije, vstopna in izstopna temperatura napajalne raztopine za sušenje na razpršilnem sušilniku. Druga faza razvoja prehrambenih kalcijevih fosfatov pa je prenos iz pilotne naprave v proizvodni proces, kjer smo definirali še preostale procesne parametre, kot so pretok napajalne raztopine na razpršilni disk, hitrost razprševanja oziroma hitrost vrtenja razpršilnega diska. Ugotovili smo, da samo s sušenjem in sejanjem ne dosežemo ustrezne porazdelitve velikosti delcev, prav tako pa samo s povečanjem hitrosti razprševanja problema neustrezne porazdelitve velikosti delcev ne rešimo. Potrebna je še dodatna operacija in to je mletje. The purpose of this master’s thesis is to show the developement of the technological process for obtaining food calcium phosphates with an emphesis on spray drying. TKI Hrastnik is the only producer of food calcium phosphates in Slovenia. Literature containing a description of the stages for producing food grade calcium phosphates are scarce, and therefore we always follow the clients demands (about the end product), when addressing and developing the technological stages. At the same time regulations are followed as demanded. The first stage in the developement of technological process for obtaining calcium phosphates was conducted at the Chemical institut in Ljubljana (Kemijski inštitut v Ljubljani), where parameters of the process, such as the pH of the feed, the temperature of the reaction, the ingoing and outgoing temperature of the feed for the spray drying were tested and defined. The experiments were conducted on a pilot plant. The second stage in the developement of technological process for obtaining calcium phosphates was the transfer of the process from the pilot plant to the production scale where we later defined the remaining parameters of the process, such as the flow of the feed onto the spray disc, and the speed of spraying/ the speed at which the spray disc rotates. It was found that with drying and sieving the suitable particle size distribution can not be achieved and that by increasing the speed of spraying this particular problem can not be solved. To properly solve this problem another process must be added into the chain – milling. |
