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Title: ANALIZA EKSPLOZIVNOSTI IN DOLOČITEV VARNOSTNIH UKREPOV PRI PROIZVODNJI ALUMINIJEVEGA PRAHU Authors: ID Novosel, Barbara (Mentor) More about this mentor... ID Balantič, Janez (Author) Files: Janez_Balantic.pdf (7,48 MB) MD5: 0D544B9E6C3ECD59E680A5EBD5629441   Janez_Balantic.zip (25,10 MB) MD5: D1D1EB72A8B35CE8DD4645F1E49FAC27   Language: Slovenian Work type: Master's thesis/paper Typology: 2.09 - Master's Thesis Organization: FZO - Faculty of Environmental Sciences Abstract: Magistrsko delo obravnava stanje na področju prašnih eksplozij v svetu. Na začetku so opisani prvi znanstveni pristopi k tej problematiki z navedbo statističnih podatkov, ki jim sledi opis znanstvenih teorij nastanka eksplozije. Zatem sledi predstavitev teoretičnih in zakonodajnih načinov za preprečitev eksplozije. Prikazana so doslej znana dejstva in različne teorije o vplivih aluminija na okolje in človeško telo. Pojasnjena je nevarnost eksplozije aluminijevih prahov ter podani napotki za varno in zdravo delo v eksplozijsko roženih prostorih. V eksperimentalnem delu smo določili osnovne karakteristike in lastnosti izbranih treh vzorcev Al prahu (dva prahova in zdrob), ki se proizvajajo. Vzorcem smo določili velikost in porazdelitev velikosti delcev, specifično površino delcev in termične lastnosti s termično analizo (TG/DTA). Obliko delcev vzorcev Al prahu smo določili z vrstično elektronsko mikroskopijo (SEM). Sledila je določitev minimalne vžigne energije MVE in maksimalnega eksplozijskega tlaka (pmax), maksimalne hitrosti rasti tlaka pri eksploziji (Δp/Δt)max ter izračun deflagracijskega indeksa prahu (Kst). Iz rezultatov analiz smo potrdili hipotezo, da so manjši delci eksplozijsko bolj občutljivi in popolneje izgorevajo ter kot taki pomenijo večje tveganje za nastanek prašne eksplozije. Ugotovili smo tudi, da so Al prahu z manjšimi delci dodani dodatki za zmanjšanje občutljivosti. Za konec smo dobljene rezultate primerjali z dostopnimi literaturnimi navedbami in ugotovili, da so odstopanja prevelika za varno uporabo. Zato je zaradi zagotavljanja zadostne varnosti pred načrtovanjem in delom priporočljivo določiti vsaj velikost in porazdelitev velikosti prašnih delcev. Ta podatek nam namreč omogoči, da v večini literature med kopico podatkov najdemo približno ustrezen vzorec. Seveda pa je potrebno za večjo verjetnost še bolje okarakterizirati vzorce in izvesti še več preizkusov, kar smo v našem primeru tudi izvedli. Vsaka eksplozija poleg takojšnjih vplivov na ljudeh in okolju pusti tudi dolgotrajne posledice, ki jih z današnjim stanjem tehnike in meritvami niti ne opazujemo in reguliramo. Zato velja, da je najboljši način preprečitve negativnih vplivov eksplozije onemogočanje pogojev za njen nastanek. Keywords: aluminijev prah, prašna eksplozija, eksplozijski parametri, varnostni ukrepi pri proizvodnji aluminijevega prahu, vpliv aluminija na okolje in človeka Place of publishing: Nova Gorica Year of publishing: 2017 PID: 20.500.12556/RUNG-3208-080e5841-1ecc-0781-b777-c93a6558d424  COBISS.SI-ID: 4895739  NUK URN: URN:SI:UNG:REP:CTIU1YWM Publication date in RUNG: 04.09.2017 Views: 7242 Downloads: 365 Metadata:    Cite this work Plain text BibTeX EndNote XML EndNote/Refer RIS ABNT ACM Ref AMA APA Chicago 17th Author-Date Harvard IEEE ISO 690 MLA Vancouver : Copy citation

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Secondary language

Language:	English
Title:	The analysis of explosions and the necessary precautions for the production of aluminum powder
Abstract:	This master's thesis deals with research on dust explosions in the world, with a brief indication of the beginnings of research and statistics, and continues to current known scientific theory of explosions and methods, theoretical and legislative, to avoid these. Hitherto known facts and theories about the effects of aluminum on the environment and the human body are presented. The risk of explosion of aluminum powder is described. The instructions for safe and healthy work in hazardous places are described as well. In the experimental part the basic characteristics and the properties of selected samples from regular production are described. Three samples of aluminum (two powders and meal) were chosen for the investigation. Due to business confidentiality the samples were marked with the letters A, B and C. Detailed analyses of the size and particle size distribution as well as the determination of the specific surface area of the particles were made. Then, a thermal analysis was performed. The samples were also examined by scanning electron microscopy (SEM) at various magnifications, in order to define a particle shape. The determinations of the minimum ignition energy MVE, the maximum explosion pressure (pmax), the maximum pressure growth rate at the explosion (Δp/Δt)max and the calculation of the dust deflagration index (Kst) were made. Based on these results we have proven the hypothesis that the smaller particles are more explosive and more combustible, and as such pose a greater risk of dust explosion. We also found out that Al powder with smaller particles contains some additives for reducing sensitivity. The results obtained from my investigations differ from the theoretical values offered by well-known literature data. Due to excessive deviations, these values are therefore not useful for safe work in practice. Therefore, in order to ensure adequate safety before planning and work, it is advisable to determine at least the size and the size distribution of the dust particles. This information enables us to find an approximate pattern in the literature data set. For precise characterization of the samples it is necessary to carry out even more tests, which we did in our case. In addition to the immediate effects on humans and the environment, each explosion leaves the long-term consequences that we do not even observe and regulate with current state of technology and measurements. Therefore, the best way to prevent the negative effects of the explosion is to disable the conditions for its formation
Keywords:	aluminum powder, dust explosion, explosion parameters, safety precautions by production of aluminum powder, aluminum influence on the environment and the human

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