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V diplomski nalogi smo proučevali anaerobno digestijo mešanic japonskega dresnovca in piščančjega gnoja, ki so bile predhodno obdelane z glivo Pleurotus Ostreatus. Pred nastavitvijo eksperimentov smo določili optimalno razmerje med biomaso dresnovca in inokuluma. Nastavili smo štiri različna razmerja glede na trdne snovi in sicer: 1(D/I) = 85:15, 2(D/I) = 70:30, 3(D/I) = 50:50 in 4(D/I) = 30:70. Med procesom anaerobne digestije smo spremljali količino in sestavo nastajajočega bioplina in merili množinski delež metana, CO2 (glavni komponenti bioplina), N2 in O2 za nadzorovanje anaerobnega procesa. Ocenili smo, da je optimalno razmerje med dresnovcem in inokulumom 80:20, saj smo želeli imeti v vhodni snovi največji možni delež rastlinskih substratov. Nato smo izvedli eksperiment, kjer so bili vhodni substrati mešanice z različnimi razmerji dresnovca in piščančjega gnoja, obdelani z glivo Pleurotus Ostreatus. Namen obdelave teh mešanic z glivo je bil, da gliva z encimi pretvori bakterijam nedostopno lignocelulozo, tako iz dresnovca kot tudi stelje iz gnoja, v substrat, katerega bakterije v procesu anaerobne digestije hitreje in lažje razgradijo, pri tem pa kot produkt nastaja bioplin. Tudi med tem procesom smo merili volumen nastalega bioplina in njegovo sestavo. Pred in po anaerobni digestiji smo določevali vsebnost trdnih snovi in vsebnost hlapnih trdnih snovi. Iz podatkov o volumnu bioplina, njegovi sestavi in vsebnosti trdnih in hlapnih trdnih snovi, smo lahko izračunali različne donose metana. Izkazalo se je, da so glive ob prisotnosti dresnovca prerasle tudi gnoj in da je bil donos bioplina pri anaerobni digestiji obdelanega dresnovca nekoliko višji kot pri neobdelanem dresnovcu. This diploma work deals with the anaerobic digestion of the mixture of Japanese knotweed and chicken manure which had previously been treated with fungus Pleurotus Ostreatus. Before setting the experiments we set the optimal ratio between the biomass of knotweed and inoculum. We set four different ratios with respect to the total solids as follows: 1(D/I) = 85:15, 2(D/I) = 70:30, 3(D/I) = 50:50 in 4(D/I) = 30:70. During the process of anaerobic digestion we monitored the amount and the composition of the created biogas and we measured the amount fractions of methane, CO2 (main components of biogas), N2 and O2 to control the anaerobic conditions. We estimated the optimal ratio between knotweed and inoculum is (D/I) = 80:20, because we wanted to have as high a proportion of plant substrates as possible in the input matter. After obtaining the optimal ratio we set up an experiment, where the inputs were mixtures with different ratios of knotweed and chicken manure, now treated with fungus Pleurotus Ostreatus. The purpose of the treatment was to use enzymes to convert bacteria inaccessible lignocelluloses, both knotweed as well as bedding from manure, into substrates which bacteria degrade with greater ease and faster during the process of anaerobic digestion, where biogas is produced. During the anaerobic digestion we measured the amount and composition of the created biogas. Before and after the anaerobic digestion we measured the content of total solids and volatile total solids. From the measurements we calculated different methane yields. It turned out that fungus can grow on manure in the presence of knotweed and that the biogas yield of anaerobic digestion of treated knotweed is slightly higher than in the case of untreated knotweed.

Varnost v kemijskih procesih postaja vse bolj pomemben vidik že v fazi načrtovanja procesa. V tem magistrskem delu smo upoštevali vidik varnosti v fazi načrtovanja omrežja toplotnih prenosnikov (OTP). Pri tem smo ocenili inherentno varnost s pomočjo mešano celoštevilskega nelinearnega programirnega (MINLP) modela najprej z osnovnim modelom. Nato smo izvedli občutljivostno analizo z različnimi tipi toplotnih prenosnikov, pri čemer smo primerjali ploščine toplotnega prenosa, mase prisotnih snovi, tlačne padce ter razmerja med volumnom in ploščino v toplotnih prenosnikih. Za vsak prenos smo dimenzionirali primeren prenosnik toplote. Izračunane podatke smo nato vstavili v posodobljen model za celotno OTP. Tako dobljene vrednosti ploščin in indikatorjev tveganja smo primerjali z začetnimi vrednostmi. Ugotovili smo, da so bile začetne ploščine vseh toplotnih izmenjevalcev precenjene. Posledično so bili napačno ocenjeni tudi stroški investicije in indikatorji tveganja. Nato smo za izbrane dimenzije toplotnih prenosnikov primerjali indikatorje tveganja za toksičnost, vnetljivost in eksplozivnost med rezultatoma, ko nismo upoštevali natančnih mer toplotnih prenosnikov ter pri upoštevanju natančnih dimenzij toplotnih prenosnikov. Rezultati kažejo, da ima natančno dimenzioniranje prenosnika za posamezne prenose toplote velik vpliv na oceno varnosti v OTP. Z dodatkom natančnega dimenzioniranja prenosnikov toplote smo omogočili natančnejše načrtovanje OTP in realnejše ocenjevanje njihove varnosti. Importance of safety in chemical processes is increasing already in the first phases of design. This master's thesis takes into account the safety aspect of heat exchangers network (HEN) in the design phase. In doing so, inherent safety was assessed using the mixed-integer nonlinear programming (MINLP) model, taking into account the precise dimensions of the heat exchangers. A sensitivity analysis was performed with different types of heat exchangers, where surfaces of heat transfer, mass of substances present, pressure drops and the ratio of volume to surface in heat exchangers were compared. We then compared risk indicators for toxicity, flammability and explosiveness for the selected dimensions of the heat exchangers between the results when the exact dimensions of the heat exchangers were considered and when they were not taken into account. The results show that accurate sizing of exchangers for individual heat transfers has a major impact on safety assessment of the HEN. A suitable heat exchanger was dimensioned for each heat exchange, and the calculated data was then inserted into the updated model for the entire HEN. The surface values and risk indicators obtained in this way were compared to the initial values. The initial surfaces of all heat exchangers were found overestimated. As a result, the costs of the investment and risk indicators were also misjudged. By adding precise dimensioning of heat exchangers to risk assessment in HEN, we have made it possible to plan HENs more accurately and evaluate their safety more realistically.