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Reception and control of steel scrap in the steel mill
No full textOvaj rad istražuje prijem i kontrolu čeličnog otpada u čeličanama kao sirovine za proizvodnju čelika. Analizirajući ekonomske, ekološke i tehničke aspekte ovog procesa, istražuje se utjecaj i način prijema i kontrole čeličnog otpada u čeličanama. Fokusirajući se na regulatorni okvir, trgovinske politike i strategije upravljanja otpadom, rad pruža uvid u postupke i izazove povezane s prijemom i kontrolom čeličnog otpada u čeličanama. Kroz pregled relevantne literature, primjere dobre prakse i studije slučaja, rad donosi zaključke o važnosti čeličnog otpada i njegove kontrole za čeličane, ističući ključne faktore uspjeha i preporuke za daljnje istraživanje i praksu.
U konačnici, rad zaključuje da čelični otpad predstavlja važan resurs za čeličane u ostvarivanju održive proizvodnje čelika te poziva na daljnje istraživanje i implementaciju politika koje potiču održivo korištenje resursa i smanjenje negativnih utjecaja na okoliš.This paper investigates the reception and control of steel scrap in steel mills as raw material for steel production. Analysing the economic, ecological, and technical aspects of this process, the influence and method of reception and control of steel waste in steel mills is investigated. Focusing on the regulatory framework, trade policies and waste management strategies, the paper provides insight into the procedures and challenges associated with the reception and control of steel scrap in steel mills. Through a review of relevant literature, examples of good practice and case studies, the paper draws conclusions on the importance of steel scrap and its control for steel mills, highlighting key success factors and recommendations for further research and practice.
Ultimately, the paper concludes that steel scrap represents an important resource for steel mills in achieving sustainable steel production and calls for further research and implementation of policies that encourage sustainable use of resources and reduction of negative environmental impacts
Light pollution
No full textOvaj završni rad se bavi temom svjetlosnog onečišćenja, istražujući njegove vrste, uzroke, metode mjerenja te učinke na okoliš, ljude i životinje. Svjetlosno onečišćenje podrazumijeva prekomjernu ili neadekvatnu upotrebu umjetne rasvjete koja negativno utječe na noćno nebo, ekosustave i ljudsko zdravlje. Različite vrste svjetlosnog onečišćenja uključuju direktno svjetlo, raspršeno svjetlo, reflektirano svjetlo te reklamno osvjetljenje. Svaka od tih vrsta ima specifične karakteristike i utjecaje. Uzroci svjetlosnog onečišćenja uključuju urbanizaciju, neadekvatno planiranje rasvjete te upotrebu zastarjelih tehnologija rasvjete. Utjecaj svjetlosnog onečišćenja na okoliš uključuje narušavanje prirodnih ciklusa svjetla i tame, što negativno utječe na biljke i životinje. Kod ljudi, svjetlosno onečišćenje može izazvati poremećaje spavanja, vizualne i psihološke učinke te povećati rizik od zdravstvenih problema, poput malignih oboljenja. Mjerenje svjetlosnog onečišćenja provodi se korištenjem različitih metoda poput fotometrijskih mjerenja, fotografskih tehnika, satelitskih snimaka i spektroskopskih analiza. Ovi podaci pomažu u kvantificiranju razine onečišćenja i razvijanju strategija za njegovo smanjenje.
Regulativa i politika usmjerene na smanjenje svjetlosnog onečišćenja uključuju zakonske propise, smjernice za urbanističko planiranje, edukaciju i podizanje svijesti te poticanje razvoja inovativnih tehnologija. Ovaj završni rad pruža sveobuhvatan pregled problema svjetlosnog onečišćenja, njegovih učinaka i mogućih rješenja, naglašavajući važnost zaštite tamnog neba za očuvanje prirodnih resursa i zdravlja ljudi.This final paper addresses the topic of light pollution, exploring its types, causes, measurement methods, and effects on the environment, humans, and animals. Light pollution involves the excessive or inadequate use of artificial lighting that negatively affects the night sky, ecosystems, and human health. The different types of light pollution include direct light, scattered light, reflected light, and advertising lighting. Each type has specific characteristics and impacts. The causes of light pollution include urbanization, inadequate lighting planning, and the use of outdated lighting technologies. The impact of light pollution on the environment includes the disruption of natural light and dark cycles, adversely affecting plants and animals. In humans, light pollution can cause sleep disorders, visual and psychological effects, and increase the risk of health problems such as malignancies. Measurement of light pollution is carried out using various methods such as photometric measurements, photographic techniques, satellite imaging, and spectroscopic analyses. These data help quantify the level of pollution and develop strategies to mitigate it.
Regulations and policies aimed at reducing light pollution include legal regulations, urban planning guidelines, education and awareness campaigns, and encouraging the development of innovative technologies. This final paper provides a comprehensive overview of the problem of light pollution, its effects, and potential solutions, emphasizing the importance of protecting the dark sky for the preservation of natural resources and human health
The effect of the inhibitor on the corrosion behavior of X37CrMoV5-1 hot work tool steel in a medium OF 3,5 % NaCl
No full textU ovom radu provedena su elektrokemijska i metalografska ispitivanja X37CrMoV5-1 alatnog čelika za topli rad interne oznake UTOPMO1 s ciljem procjene njegove otpornosti na koroziju u kloridnom mediju s i bez dodatka inhibitora. Tafelovom ekstrapolacijom polarizacijskih krivulja dobivena je manja brzina korozije ispitanog alatnog čelika u 3,5 % otopini NaCl s dodatkom inhibitora, što potvrđuje učinkovitost inhibitora VCI 379/611 u smanjenju brzine korozije. Elektrokemijskom impedancijskom spektroskopijom dobiveni su parametri impedancije, pri čemu je registriran veći otpor prijenosu naboja alatnog čelika u 3,5 % otopini NaCl s dodatkom inhibitora, što upućuje na činjenicu da se adsorbiranjem inhibitora na površini uzorka stvorio deblji oksidni sloj, koji štiti čelik od daljnjeg prodiranja agresivnih kloridnih iona iz otopine. Mikrostruktura ispitanog čelika je sitnozrnata te u osnovi martenzitna s jednolikom raspodjelom karbida, čime se postiže bolja korozijska otpornost. Metalografska ispitivanja su potvrdila navedene rezultate elektrokemijskih ispitivanja, jer su registrirani izraženiji korozijski produkti na uzorku izloženom 3,5 % otopini NaCl bez dodatka inhibitora.In this work, electrochemical and metallographic tests of X37CrMoV5-1 hot work tool steel designated as UTOPMO1 were carried out with the aim of evaluating its corrosion resistance in a chloride medium with and without the addition of inhibitor. By Tafel extrapolation of the polarization curves, a lower corrosion rate of the tested tool steel was obtained in a 3,5 % NaCl solution with the addition of an inhibitor, which confirms the effectiveness of the VCI 379/611 inhibitor in reducing the corrosion rate. Impedance parameters were obtained by electrochemical impedance spectroscopy, where a higher charge transfer resistance of the tool steel was registered in a 3.5% NaCl with the addition of an inhibitor, which points to the fact that adsorbing the inhibitor created a thicker oxide layer on the surface of the sample, which protects the steel from further penetration of aggressive chloride ions from the solution. The microstructure of the tested steel is fine-grained and basically martensitic with a uniform distribution of carbides, which achieves better corrosion resistance. Metallographic tests confirmed the stated results of electrochemical tests, as more pronounced corrosion products were registered on the sample exposed to a 3,5 % NaCl solution without the addition of inhibitors
The impact of chemical substances on the health of workers in public healthcare
No full textIzlaganje kemijskim supstancama u sektoru javnog zdravstva predstavlja složen problem s ozbiljnim posljedicama na zdravlje radnika. Unatoč ključnoj ulozi koju javno zdravstvo igra u očuvanju i unapređenju zdravlja populacije, često se zanemaruje činjenica da radnici u ovom sektoru redovito dolaze u kontakt s različitim kemikalijama koje mogu ozbiljno ugroziti njihovo zdravlje. Radno okruženje u javnom zdravstvu varira od bolnica do laboratorija, ali izloženost kemikalijama predstavlja zajednički izazov. Medicinsko osoblje, laboratorijski tehničari i čistači suočavaju se s različitim kemijskim tvarima u svakodnevnom radu, uključujući dezinfekcijska sredstva, lijekove, anestetike i kemikalije za čišćenje. Izloženost tim kemijskim tvarima može proizlaziti iz različitih izvora, uključujući nepravilno rukovanje, nedostatne ventilacijske sustave i nepoštivanje sigurnosnih protokola. Posljedice takve izloženosti mogu uključivati respiratorne probleme, kožne reakcije, kancerogenost i neurološke poremećaje. Ključno je razumjeti utjecaj ovih kemikalija na zdravlje radnika kako bi se poduzele odgovarajuće mjere prevencije i zaštite. Tehničke, organizacijske i osobne mjere zaštite igraju ključnu ulogu u smanjenju rizika. Identifikacija specifičnih kemikalija u sektoru javnog zdravstva i analiza njihovog utjecaja pomažu u boljem razumijevanju rizika. Naposljetku, promicanje svijesti o ovim izazovima i primjena odgovarajućih mjera zaštite ključni su elementi za osiguranje sigurnog radnog okruženja za radnike u javnom zdravstvu. Ovaj istraživački rad pruža dublji uvid u probleme s kojima se suočavaju ti radnici i kako se te probleme tretira kako bi se zaštitilo njihovo zdravlje i dobrobit.Exposure to chemical substances in the public healthcare sector represents a complex issue with serious implications for the health of workers. Despite the crucial role that public healthcare plays in preserving and improving the health of the population, it is often overlooked that employees in this sector regularly come into contact with various chemicals that can pose significant risks to their health. The working environment in public healthcare varies from hospitals to laboratories, but exposure to chemicals is a common challenge. Medical staff, laboratory technicians, and cleaners encounter various chemical substances in their daily work, including disinfectants, medications, anesthetics, and cleaning chemicals. Exposure to these chemical substances can originate from various sources, including improper handling, inadequate ventilation systems, and non-compliance with safety protocols. The consequences of such exposure can include respiratory problems, skin reactions, carcinogenicity, and neurological disorders. It is crucial to understand the impact of these chemicals on workers' health to take appropriate prevention and protection measures. Technical, organizational, and personal protective measures play a pivotal role in reducing risks. Identifying specific chemicals in the public healthcare sector and analyzing their impact helps enhance the understanding of risks. Ultimately, raising awareness of these challenges and implementing appropriate protective measures are key elements in ensuring a safe working environment for public healthcare workers. This research provides a deeper insight into the issues faced by these workers and how these issues are addressed to safeguard their health and well-being
Risik assessment in trade and service activity
No full textU ovom završnom radu obuhvaćena su objašnjenja osnovnih pojmova zaštite na radu kako bi
se pružio bolji uvod u samu procjenu rizika u trgovačko-uslužnoj djelatnosti te opasnosti,
štetnosti i napore kojima su izloženi radnici u ovom sektoru. Metodologija procjene rizika
uključuje identifikaciju opasnosti putem analize radnih mjesta, provođenje procjene rizika
koristeći standardne alate i metode te predlaganje mjera za smanjenje rizika. Naglasak je na
kontinuiranom praćenju i unapređivanju praksi te važnosti osvještavanja i edukacije
zaposlenika s ciljem postizanja što veće sigurnosti i očuvanju zdravlja na radnom mjestu.This thesis covers explanations of the basic concepts of occupational safety to provide a better
introduction to risk assessment in the trade and service sector, as well as the hazards, harmful
effects, and efforts to which workers in this sector are exposed. The risk assessment
methodology includes the identification of hazards through job analysis, conducting risk
assessments using standard tools and methods, and proposing measures to reduce risks.
Emphasis is placed on continuous monitoring and improvement of practices, as well as the
importance of raising awareness and educating employees to achieve maximum safety and
preserve health in the workplace
Detection and analysis of non-conformities in S355JR non-alloy structural steel
No full textAlthough construction materials are considered the most predictable components of a construction project, design and material challenges represent a major cause of productivity loss. The occurrence of non-conformities is a consequence of the very difficult quality assurance under industrial conditions, especially in the context of material processing. In this paper, non-conformities detected during the ultrasonic testing of the steel infrastructure were analysed. The investigation of non-conformity area included the chemical composition analysis, the thermodynamic calculations of the solidification sequence and metallographic analysis. The ultrasonic test results indicated the crocodile effect associated with the thermomechanical processing of steel ingots containing casting defects. This fact was supported by the results of the non-equilibrium solidification sequence. Microstructural analysis of the non-conformity area indicated the presence of non-metallic inclusions and cracks. The crack nucleation and propagation occurred during the thermo-mechanical processing. The microstructure constituents also indicated improperly performed thermo-mechanical processing. The rolling texture and acicular ferrite pointed to improperly performed normalization. The conducted research indicates the need to impose additional requirements on the microstructure of the final product, although it is not required by the EN 10025-2:2019 standard
Measurement of illumination in the plant for the production of bee scones
No full textSvjetlost kao pojava proučava se već nekoliko tisuća godina, a uz nju se vežu i razne teorije u vezi njezina širenja. Čovjek opaža svjetlost osjetilom vida te unutar ograničenog raspona njezinih valnih duljina koje može zamijetiti, raspoznaje vrlo sitne razlike koje vidi kao boje. U suvremenom svijetu čovjek je svakodnevno izložen svjetlosti, bilo onoj prirodnoj ili umjetnoj, no najveći problem za njegovo zdravlje predstavlja izloženost umjetnom svjetlu koje imitira dnevnu svjetlost. Čovjekov jednodnevni biološki ritam ili cirkadijani ritam određuje osnovne fiziološke aktivnosti prema izmjeni dana i noći. Isti je odgovoran za proizvodnju melatonina koji je antioksidans u borbi protiv nastanka stanica raka. Umjetno svjetlo u noćnim satima te noćni rad mogu poremetiti proizvodnju melatonina i na taj način izložiti organizam raznim oboljenjima. Danas postoje dokumenti koji čine zakonodavni okvir u vezi osvjetljenja na radnom mjestu, a koji daju garanciju za njegovu sigurnu i kvalitetnu primjenu. To su Zakon o zaštiti na radu kao temelj za izradu mnogih Pravilnika u vezi osvjetljenja na radnom mjestu te norme za svjetlo i rasvjetu unutarnjih i vanjskih radnih mjesta. Rasvjeta je danas prisutna na svakom radnom mjestu, a podijeliti se može na unutarnju i vanjsku. Izbor rasvjete ovisi o nizu čimbenika kao i njenoj namjeni. U ovom radu su prikazani rezultati mjerenja rasvijetljenosti u pogonu za proizvodnju pčelinjih pogača s obzirom na mjerna mjesta koja obuhvaćaju pogon, skladište i mlin. Cilj ovog istraživanja je provjera usklađenosti postojećeg rasporeda rasvjetnih tijela s važećim propisima. Mjerenjima je ustanovljeno da je potrebno preispitivanje i poboljšanje rasvjetnih tijela te usklađivanje rasporeda rasvjetnih tijela s važećim propisima i rasvijetljenosti pojedinih radnih mjesta koja moraju biti sigurna, funkcionalna i estetski ugodna.Light as a phenomenon has been researched for several thousands of years, and in relation to it, there are different theories about its expansion. A human observes light with a sense of sight and within a limited range of its noticeable wavelengths very tiny differences are recognized as colours. In a modern world, we are exposed to everyday light, both natural and artificial one. However, the biggest problem for our health is the exposure to artificial light, which imitates daily light. A person's one-day biological rhythm or a circadian rhythm determines basic physiological activities according to the change of day and night. It is responsible for the production of melatonin, an antioxidant that fights against the development of cancer cells. Artificial light used during the night, as well as night work, can disrupt production of melatonin and that way expose our organism to various diseases. Nowadays, there are documents making a legal framework in connection to lighting at workplace, which guarantee for its safe and quality use. These are The Employment Protection Act as the foundation for making many other Rulebooks related to lighting at workplaces, as well as the norms for light and illuminance of indoor and outdoor workplaces. The choice of lighting depends on a number of key factors, as well as its purpose. In this work, the results of illuminance measurement in the plant for the production of bee scones concerning the measurement spots encompassing the plant, the warehouse and the mill, were be presented. The purpose of these investigations is the review of compatibility of the existing arrangement of lighting units to valid regulations. The measurements showed that there is a need to review and improve the lighting fixtures and to harmonize the layout of the lighting fixtures with current regulations and the lighting of individual workplaces, which must be safe, functional and aesthetically pleasing
Sigurnost i zaštita na radu pri zavarivanju
No full textU završnom radu pregledno je analiziran širok spektar sigurnosnih mjera kojih se treba pridržavati prilikom zavarivanja. Fokus je na identificiranju opasnosti koje se javljaju tijekom različitih postupaka zavarivanja te važnosti primjene odgovarajućih sigurnosnih mjera radi zaštite radnika. Kroz detaljnu analizu, naglašena je ključna uloga zaštitne opreme, poput zaštitnih naočala, rukavica, odjeće i obuće, u sprječavanju ozljeda i osiguranju sigurnog radnog okruženja. Dan je naglasak na važnost kontinuiranog obrazovanja zaposlenika o sigurnosnim procedurama kako bi se osigurala adekvatna primjena propisanih mjera. Navedeni zaključci naglašavaju važnost stalnog unaprjeđenja sigurnosnih standarda i praksi u industriji zavarivanja radi zaštite zdravlja i dobrobiti radnika, te očuvanja materijalne imovine.This comprehensive thesis delves into the critical safety aspects associated with welding operations. The primary focus lies on identifying hazards that arise during various welding procedures and emphasizing significance of implementing appropriate safety measures to safeguard workers. Through a detailed analysis, the pivotal role of personal protective equipment (PPE), including safety glasses, gloves, clothing, and footwear, in preventing injuries and ensuring a safe working environment is underscored. The importance of continuous employee training on safety procedures is also highlighted to ensure the proper implementation of prescribed measures. The findings presented underscore the cruciality of continuous improvement in safety standards and practices within the welding industry to protect the health and well-being of workers, safeguard property, and minimize environmental impact
Human factors and technological aspects of fire safety
No full textPožari su jedan od najvećih sigurnosnih izazova za građevinske objekte i industrijska postrojenja, s potencijalno katastrofalnim posljedicama. Razumijevanje uzroka požara, kao što su električni kvarovi, loše održavanje instalacija, kemijske reakcije ili ljudska nepažnja, ključno je za razvoj preventivnih strategija i tehnologija koje omogućuju njihovo sprječavanje i brzu intervenciju. Ponašanje ljudi u kriznim situacijama, poput požara, često je obilježeno panikom i dezorijentacijom, što može otežati pravovremenu reakciju. Stoga je važno razumjeti psihološke aspekte ovih reakcija za bolje planiranje evakuacije i obuke. Uz to, tehnološki napredak, uključujući razvoj novih protupožarnih materijala i naprednih sustava za detekciju požara, presudan je za unaprjeđenje požarne sigurnosti i smanjenje rizika. Ovaj rad istražit će ključne aspekte požarne sigurnosti s naglaskom na prevenciju, tehnologiju i ljudski faktor kako bi se osigurala sigurnija okruženja u budućnosti.Fires represent one of the greatest safety challenges for construction sites and industrial facilities, with potentially catastrophic consequences. Understanding the causes of fires, such as electrical faults, poor maintenance of installations, chemical reactions, or human negligence, is crucial for developing preventive strategies and technologies that allow for their prevention and swift intervention. Human behavior in crisis situations, such as fires, is often marked by panic and disorientation, which can hinder timely responses. Therefore, understanding the psychological aspects of these reactions is important for better evacuation planning and training. Additionally, technological advancements, including the development of new fire-resistant materials and advanced fire detection systems, are crucial for enhancing fire safety and reducing risks. This paper will explore key aspects of fire safety with a focus on prevention, technology, and human factors to ensure safer environments in the future
NaTech accidents and disasters
No full textU ovom radu dan je pregled koncepta NaTech nesreća i katastrofa koje su se dogodile u svijetu kao i posljedice koje su prouzrokovale. NaTech nesreće i katastrofe predstavljaju složen spoj prirodnih katastrofa i tehnoloških nesreća, često rezultirajući ozbiljnim posljedicama po ljudske živote, životnu sredinu i ekonomiju. Cilj rada je analizirati faktore koji doprinose nastanku Natech nesreća i katastrofa, kao i ukazati na važnost razvoja strategije za njihovu prevenciju i smanjenje štetnih posljedica. Rad ističe nespremnosti država za adekvatni odgovor na NaTech nesreće te važnosti razrade pripravnosti za pravodobno reagiranje u takvim nepredvidivim nesrećama i katastrofama. Važno je poraditi na jasnim i učinkovitim propisima kako bi se potencijalna opasnost prepoznala i kontrolirala. Ključno je istovremeno analizirati prirodne katastrofe i njihove posljedice kako bi se identificirali potencijalni načini ublažavanja negativnih učinaka. Razvijanje strategija i planova djelovanja za takve situacije omogućuje bržu i koordiniranu reakciju, što rezultira manjim štetama i bržim oporavkom. Također, važno je educirati građane o pravilnom postupanju u takvim situacijama, surađujući s lokalnim vlastima kako bi se postigla bolja pripremljenost i odgovornost zajednice.This paper reviews the NaTech concept of accidents and disasters that have occurred in the world and the consequences they have caused. NaTech accidents and disasters represent a complex combination of natural and technological disasters that often have serious consequences for human life, the environment, and the economy.The aim of the paper is to analyze the factors that contribute to the occurrence of NaTech accidents and disasters and to point out the importance of developing a strategy to prevent them and reduce their harmful consequences. The paper highlights the inability of states to respond adequately to NaTech accidents and the importance of making provisions for timely response to such unpredictable accidents and disasters. It is important to work on clear and effective regulations to identify and control the potential hazard. It is critical to simultaneously analyze natural disasters and their consequences to identify possible ways to mitigate the negative impacts. Developing strategies and action plans for such situations will allow for a faster and more coordinated response, resulting in less damage and faster recovery. It is also important to educate citizens on how to properly handle such situations and to work with local authorities to achieve better community preparedness and responsibility