Optimization of the laboratory brewery vessel washing conditions

Abstract

U ovom istraživanju praćene su različite koncentracije metalnih iona (aluminija, bakra, željeza, molibdena i kositra) u vodi za ispiranje kotla za kominu laboratorijske minipivovare. Proces ispiranja optimiran je obzirom na vrijeme ispiranja te na koncentraciju nitratne kiseline u vodi za ispiranje kotla za kominu. Postupak dizajniranja eksperimenta, optimiranja procesa ispiranja i predviđanja ponašanja sustava provedeno je pomoću računalnog programa Design Expert (verzija 7, kompanije State-Ease, USA). Određeni su optimalni uvjeti ispiranja (idealno vrijeme ispiranja i koncentracija nitratne kiseline u vodi za ispiranje) korištenjem dva kriterija: minimalno dopuštenoj koncentraciji nitratne kiseline za ostvarivanje zadovoljavajućeg ispiranja (prema protokolu o sanitaciji pivovara) i maksimalno dopuštenim koncentracijama teških metala (prema Zakonu o vodama NN 107/95, 150/05). Optimirane vrijednosti zadovoljavaju navedene kriterije te se mogu primijeniti u sanitaciji industrijskih pivovara.In this research different concentrations of heavy metal ions (Al, Cu, Fe, Mo and Sn) were monitored in the waste water used to rinse the laboratory brewery vessel. The rinsing process was optimized considering the time of rinsing and the nitric acid concentration in the solution prepared for rinsing the vessel. Experiment design, rinsing optimization and system prediction was made using computer program Design Expert (version 7, State-Ease Company, USA). Optimization conditions were determined (optimal rinsing time and concentration of nitric acid in the solution prepared for vessel rinsing) using two criteria: minimum concentration of nitric acid allowed for satisfying vessel rinsing (according to brewery sanitation protocol) and maximum concentration of nitric acid allowed (according to Water Act NN 107/95, 150/05). Optimized values satisfy the criteria and could be used in sanitation of industrial breweries