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Adaptability of Powdered Activated Carbon Production from Ground Catering Waste Pyrolysis Coke
162-171Views:314Three mixture of catering waste was pyrolyzed at 650, 725 and 900 °C and the solid residue (coke) was examined for powdered activated carbon production. For this, the carbon content, iodine number, particle size distribution and scanning electron microscopic images were analysed. Based on the carbon content, these cokes are suitable for activated carbon production, which were 60-85 wt.% (depending on the base material and pyrolysis temperature). The studied cokes showed slightly porous structure with smooth surfaces. Because of this, the iodine number was mostly small (13-30). Based on the grinding experiments, 10 minutes of grinding was found to be optimal. After this grinding time, the reached iodine number of powdered activated carbon was 350-610.
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Flexibility Analysis Of Inventory Cost Model With Ergonomics
166-173Views:318The economic and environmental sustainability issues in supply chain management have integrated by many researchers in the past decades. The ergonomics as a social aspect of sustainability had received a little attention by researchers. Therefore, the aim of the paper is analyzing the flexibility of developed inventory cost model with relaxation allowance and endurance time as a social aspect of sustainability. The effects of distance, unit weight of item and total number of items on relaxation allowance, the total cost of logistics operation and the EOQ model were investigated. The analyzed mathematical model was a single operator-single material model which covered transportation of fixed amount of raw materials from storage plant to production plant by manual material handling with simple cart and picking, storing, pushing and pushing back with empty cart for manual handling of the products. The different parameter values applied for analysis such as total amount of handled items (Q) changes between 500 pcs to 2750 pcs, unit weight of item (w) changes between 0.1 kg to 1 kg, distance of movement by manual material handling for picking and storing motions (d1) changes between 2 m to 3 m and the distance between the storing equipment and the supermarket of the production line for pushing motion (d2) changes between 15 m to 20 m. The results of the analysis indicated that the longer the distance of movement for all motions leads to decrease in savings of the model compared to EOQ model. The increase in unit weight of item is increase the savings obtained from application of our model and decrease the optimal lot size. There was no specific change on savings or optimal lot size as the total amount of handled item is increase. The compared results indicated that an increase in d1 and d2 lead to an increase in optimal lot size and increase in total cost of the model. Consequently, the analysis has shown that a decrease in lot size would be the better way to improve both ergonomic conditions and total cost of production in any different parameter values. Finally, the analysis of the inventory model with ergonomics were proved that this model is suitable for different industrial practices.
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Simulation of Hot Rolling by Cellular Automata
190-195Views:375Our research is focusing to one of the most complex and important production step of flat rolled products that is the simulation of hot rolling. During hot rolling two phenomena as work hardening and the process of regeneration of crystals has strong influence for physical properties of microstructure of aluminium alloys. It needs to be taken into account in case of rolling technology steps and development. When we talk about aluminium the dynamic softening in fact it is dynamic recovery that is followed by dynamic recrystallization. It goes in the same order of magnitude rate. But in steels the recovery has only a minor effect. Hot rolled and newly modified grain structure is influenced by these dynamic phenomena. Hot rolled grain structure goes through significant changes under further production steps like cold rolling and heat treatments. But aside from these intermediate production steps the microstructure that we get after hot rolling has significant effect for mechanical and grains structure of the final flat rolled product. Proper technology planning is essential that for cellular automata simulation method can ensure useable and good solution for the simulation of recrystallization.
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Operating a Webshop in Rural Areas
242-251Views:401The importance of e-commerce in Hungary is unquestionable. 66% of the population is regular internet users (I3), every fourth person uses it on a daily basis. Online sales have increased from 137 billion HUF in 2010 to 427 billion HUF in 2016, while offline sales were not able to reach this growth (I1). Undoubtedly, online sale has become a very valuable market. The age group really valuable as consumers spends about 6 hours a day online, out of which 3 hours are active usage (I2). The Internet is also the most important source of information and keeping in contact, as 41% of the population uses it method. The availability of the Internet in Hungary is literally independent of the geographic location, thanks to the Digital Renewal Action Plan in Hungary's current strategy, as one of its main chapters is "Enhanced and Secure Infrastructure for All." (Botos 2013) plan. There are many unfavorable processes in Hungary's rural areas. Of these, emigration and the abandonment of the local economy are outstanding. To stop these processes, the "National Rural Strategy" (2012-2020) was created. Its most important areas are employment growth, balanced and diverse land and forest management, production structure, restoration of local food production and food markets, local energy production, strengthening the local communities, improvement of population patterns and conservation of natural systems and the biodiversity. The integration of rural economies into the on-line marketplace and their linkage to different DBEs not only vertically but horizontally can be one of the keys to their survival and development. The situation of businesses on the on-line marketplace in the countryside is very special. On the one hand, they are more favourable in many aspects of their operation, but in some cases they have disadvantages that fundamentally threaten their survival. The purpose of this article is to get to know this environment, map its benefits and drawbacks. For this, we use the results of in-depth interviews conducted with businesses operating on an on-line market in rural settlements.
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The Relationship Between Renewable Energy Consumption, Net Energy Import, Greenhouse Gas Emission and Human Cap
58-71Views:365The measures to improve energy efficiency and increase of renewable energy production and consumption should be encouraged in the interest of sustainable development. Many factors can influence the use of renewable energy such as the level of economic development of an economy, nationals’ and the main economic actors’ environmental awareness, energy import dependency, ratio of the urban population, and government subsidization intensity among the others. The main purpose of this study is to examine the relationship between the share of renewable energy in the total energy consumption and net energy import as a percentage of energy use less production, greenhouse gas emission per capita and human capital using by OECD countries data from 1990 to 2014. The results indicate that there is a negative relationship between net energy import and renewable energy consumption, and also negative relationship can be shown between the amount of greenhouse gas emission per capita and renewable energy consumption. However, we identified a positive relationship between human capital and renewable energy consumption for energy importer countries above a certain level of human capital.
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Learning Curve Based Sigma Level Determination in Interrupted Non-Production Processes
260-270Views:272The philosophy and methods of six sigma process development have been applied successfully since mid1980s, and the application of the six sigma concept in non-production processes has increased significantly in the last decade. In this paper processes that can be characterized by learning curves are modeled. The quality of such processes can be analyzed on the basis of the six sigma concept. In this paper two back office processes are analyzed. The processes are built up of simple repeated steps and incorporate some interruptions. The application of the model allows the calculation of the maximally permitted number of interruptions in the process if the preliminary determined norm is to be kept.
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R&D infield of “Waste-to-Energy”in Institute of Raw Materials Preparation and Environmental Processing, University of Miskolc
49-57Views:268The importance of research and development in the field of „Waste-to-Energy” is vital in our modern society trying to establish the circular economy. Such R&D activity has been carrying out at Institute of Raw Materials Preparation and Environmental Processing for decades in several directions. This paper deals with the main results of research on refuse derived fuel from MSW, biogas production, briquetting of biomass, as well as production of fluid fuels.
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Ultrasonic Powder Atomization for Additive Manufacturing
69-75Views:548The following article presents a special case of metal powder production, ultrasonic metal atomization. In this case, ultrasound technology is based on the capillary wave phenomenon. We verify the suitability of the produced powders for 3D metal printing with various tests. In the case of prints with a metal powder bed fusion (PBF), the properties of the raw material of the powder are extremely important. The main results of the tests carried out in the article (SEM images, EDS composition analysis, sieve analysis) were described.
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Global and Domestic Status and Prospects of Green Biomass Utilization
85-105Views:331Nowadays, the energy consumption of global population is depending on fossil fuels, but the role of renewable energies has been increasing rapidly, primarily due to the depletion of fossil fuels, the appreciation of environmental problems and climate policies. Biomass is the fourth most important energy resource in the world, provided an estimated 70% of global renewable energy supply. However, the annual growth rate of biomass is lagging behind modern renewable energy sources. The type of biomass is very diverse and can be processed and utilised by different methods. Currently, in the "green chemistry" industry (the replacement of petroleum-based, synthetic chemical raw materials with bio-based compounds from plant biomass), the importance of combustion, pyrolysis, biogas, bioethanol, biodiesel and basic chemical compounds production have been increasing. The objectives of the present research is to analyse the global and domestic status of renewable energies and biomass production, furthermore the possibilities of utilization of perennial, herbaceous biomass plant, the giant reed (Arundo donax L.), with which has been conducting research for numerous years at the University of Debrecen.
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Human security issues of deep wells retraining
114-123Views:283Nowadays, in the world's energy production structure, fossil fuels dominate and at the same time cause a number of environmental problems. Comparing the use of conventional fossil fuels with geothermal energy, this kind of energy production is extremely beneficial, as there are no pollutants and a renewable energy source. Moreover, if we want to compare geothermal energy with other renewable energy sources (such as wind energy, solar energy, etc.), much of the benefits can also be attributed to geothermal energy becouse it is a stable energy source and the area requirement is low. Due to these extremely favorable properties, the study of the applicability of geothermal energy is gaining ground in renewable energy sources. In addition, it is well known that there are approximately 20 to 30 million abandoned oil wells in the world, plus sealed wells for other purposes, and the final number may be much larger. In the case of abandoned oil wells, the escaping residual oil may be a problem, which can lead to significant environmental problems. Taking these factors into account, research on the recyclability of abandoned wells for geothermal purposes becomes a target for more and more research topics around the world. It is interesting to note that a significant part of the publications are concerned with examining the technological potential of energy utilization, studying heat transport processes, and generating general, energetic or economical evaluations. A publication of a kind that would have evaluated the safety of recyclable abandoned wells in publishing databases was limited. It is therefore an important question that the abandoned wells, from the point of view of human security and environmental protection. How can they be reactive, how can the new technological elements be built up and how much human security factors of the newly created system are affected by the existing elements?
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The Possible Job Creation and Job Destructive Effects of Technological Development
53-61Views:542Throughout history, technological change has often provided the basis for employee anxiety. Between 1811 and 1816, a group of workers in England who called themselves "Luddists" destroyed machines, because they thought it would endanger their workplace. 19th-century thinkers and economists such as Karl Marx and David Ricardo predicted that mechanizing the economy would ultimately worsen workers' conditions, depriving them of a decent wage. Over the last century, John M. Keynes (1930s) and Wassily Leontief (1950s) have expressed their fears that more and more workers will be replaced by machine solutions that will lead to unemployment. In recent years, Brynjolfsson and McAfee (2014) have argued that existing technologies reduce the demand for labor and put some of the human workforce at a permanent disadvantage. However, there are a number of compensation mechanisms that can offset the initial displacement effects of automation and process innovation in general (Vivarelli, 2015). First of all, while workers are being replaced in industries that introduce new machine technology, additional workers in new industries are needed. Second, automation (and process innovation in general) reduces average costs. Acemoglu and Restrepo (2017) found that this results, on the one hand, in the effect of price productivity (“priceproductivity”) (as production costs decrease, the industry can expand and increase labor demand); and, on the other hand, it leads to economies of scale in production (the reduction in costs due to automation leads to an increase in total output and increases the demand for labor in all industries). Similarly, Vivarelli (2015) argues that lower average costs can result in lower prices (if the industry's market structure is perfectly competitive), stimulate product demand, or result in extra profits (if the industry's structure is not perfectly competitive). If these extra profits are reinvested in the company, this investment can create new jobs. The presentation intends to present these counterbalancing cases and to provide real examples based on the literature.
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Operational Feasibility Assessment of Geothermal Heat Harnessing Systems
46-53Views:379Renewable energy sources are now essential to establish sustainable development. This paper examines one kind of source the geothermal energy. For geothermal energy when combined with a heat pump COP can be used for evaluation. For solely geothermal sources different approach is needed thus in the paper, a new geothermal heat production coefficient is used to examine the operational feasibility. For the assessment, many hypothetical buildings were created to model their heat demands. Two types of calculation methods are used for heat demand calculation. Based on the results, the maximum depth of a geothermal borehole and economically critical qualitative coefficient was concluded.
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Municipal Geothermal Systems: Evaluation of Three Hungarian Cases
81-93Views:432Geothermal energy holds great potential for a sustainable future, as it is a clean and weather-independent form of energy. In addition to energy production, it can also serve the population of a region through direct use. In this paper, three municipal geothermal systems (Szarvas, Nagyszénás, Békéscsaba) in the same Hungarian region which have been recently installed or expanded are presented and analysed. Here, the direct usage of geothermal energy for heating purposes is a very important issue. The three systems show several differences and to some extent face different challenges in the various phases of the projects. Particular attention has been paid to engineering solutions to the problems that arise. The challenges, such as technical difficulties during installation, maintenance difficulties, or problems arising during operation are introduced. The strengths, weaknesses, opportunities, and threats of similar geothermal systems were summarized, based on the relevant literature. These points were evaluated by their appearance and characteristics in the examined systems. This study aims to provide insights, based on recently gained experiences, into geothermal projects, thus providing feedback and practical information for researchers and practitioners.
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The impact of realization of solar power plant installation requests in Mandatory Purchase (KÁT) system on the electricity supply of Hungarian settlements
54-60Views:301The support system of renewable energy production was changed in Hungary in 2017. The legislator created the Mandatory Purchase (KÁT) system earlier to encourage the electricity production from renewable energy sources and waste. The Renewable Energy Subsidy System (Metár) changed the Mandatory Purchase (KÁT) system from the 1st of January in 2017. It had been known before Metár came into force that the supported period in the Matár would be only 13 years while it was 25 years in the KÁT. Therefore, a real rush started for the KÁT support licenses in 2016 in order to make more beneficial contracts by the investors. At the time, the Hungarian Energy and Public Utility Regulatory Authority (MEKH) released a record amount of licenses (more than 2000 pieces) to build solar power plants under 500 kW performance. This is more than 1000 MW total power. This paper searches the answer how this solar power plants will influence the level of self-sufficiency of the Hungarian settlements in the electricity supply if those are realized. Hereinafter, we will analyze the possible impact of these solar power plants in the settlement electricity self-sufficiency.
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Design and Implementation of BHN Testing Equipment To Measure Remaining Stress Of Wheelset Parts (Tie Rod and Stabilizer Bar)
337-341Views:359Nowadays in the automotive industry both production and service, requires accurate lifetime calculations. Today we have big amount of theoretical background and nowadays the importancy of technical and industrial databases become more and more important. By materials scientific and fracture mechanics aspects are well covered, but the remaining stresses which are present in every step of production, we can not clearly identify the origin of them. There are different paralell methods to mesure them, but the application of different methods are depending on the engineers, and their expreiences at the company. This part of the analysis is not standardised yet, so there are differences even in the same company.
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Analysis of Social Media Activities - Through the Examination of Handball Clubs Competing at Different Levels
39-53Views:652In Hungary, handball enjoys special attention and support, this is true not only for our country, but also for Europe, and the sport is gaining more and more space worldwide. One of the biggest innovations of the last two decades is certainly social media, which has reformed the basic strategies related to information transfer and traditional marketing activities. The processes of content production on these platforms have radically changed, which every sports club should pay attention to, as they can gain significant advantages in terms of economics, marketing and community building if they are able to communicate well. Three sports clubs competing at different levels were compared during a qualitative study in terms of their social media marketing strategy activities, namely PICK Szeged, Balatonfüredi KSE – BFKA Balatonfüred and DEAC handball team. The basic concept of this research model was built on how the online marketing communication activities of club teams fighting for different professional goals at different levels differ from each other, as well as what are the development opportunities and aspects that can be used as effectively as possible on social media platforms. The handball club teams agreed on several research questions, but a significant difference could also be discovered in one area, in which the professionals responsible for social media disagreed or represented a different point of view. Looking at my results, it can be concluded that behind a successful online marketing strategy there is always serious preparation and planning work, as well as the diversification of content production on different platforms, because the consumer communities of the platforms are also different from each other.
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Laboratory-scale gasification of brown coal and char from RDF pyrolysis
188-193Views:295The pyrolysis is a promising process for producing syngas from wastes. However, the by-product of the technology may contain large quantities of carbon, therefore it is suitable for further syngas production. In this paper we examined the steam gasification of brown coal from Felsőnyárád and char from RDF pyrolysis derived from an experimental pilot plant operating in Zalaegerszeg. We performed our experiments in a laboratory-scale fix-bed reactor at 900 °C. The aim of this work to examine the efficiency of syngas production from pyrolysis char, as well as to explore the similarities and differences of the thermal decomposition of the feedstock materials.
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Business Process Development with the Application of Simulation Technique
109-118Views:387The object of our work to increase production efficiency with the use of cost-efficient development tools at a Hungarian small enterprise. We apply data gathering techniques besides process modelling and diagnostic methods to reduce the total process time of the assembly process so as to induce cost reduction in the production. In this respect we investigate and rank root causes of wastes by cost-effective process development tools, like timebased FMEA (failure mode and effects analysis) as well as the 5 whys method. With the use of Monte-Carlo simulation companies can evaluate the change in the process, therefore, they can decide whether they want to carry out corrective measures or not. The accomplished changes can generate increasing competitive edge in the long run.
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A Wounded Soldier Fighting on two Fronts: Civil Society Organizations Initiatives Struggling to Overcome the Pandemic Crisis by Practical Protective Means, Volunteerism, Reporting and Awareness Campaign Discourse
136-151Views:373Given the fact that the covid-19 pandemic virus has had a pervasive impact on almost every sphere of life globally, it is noteworthy to highlight the role and position of the civil society sector, and this paper intends to do so by striking at two matters. Initially, outlining the impact on the functioning and activities of Civil Society Organizations (CSOs), to then proceed with their response to the crisis, through new multifarious initiatives/activities. The analysis was developed by using, essentially, unobtrusive data and direct non-participatory observations of Non-Governmental Organizations (NGOs) in Kosovo that have had initiatives against covid-19. Although CSOs were badly affected by the pandemic as such, and the consequences it brought, whether, through measures and/or neglect from the central level, they still found the resources and willingness to launch initiatives to combat the pandemic in the form or different. All over the country, appeared organizations which among their activities found a place for awareness campaigns, material and financial assistance to citizens in need, production of masks, face shields, and other protective equipment for citizens or health institutions, and providing voluntary assistance as health staff. To link practice with theory, there are presented cases of NGOs that well reflect scholarship ideas such as the need to have a classification of CSOs based on activities, the importance of their IT repertoires, coproduction, and especially the response to the crisis. The importance of this study grounds on the benefit it brings to understanding the role and contribution of CSOs in exceptional times of crisis, especially for a society that underestimates and neglects this sector.
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Six Sigma in preconstruction: case study on improving of reinforcement steel processing
49-60Views:358Lean process improvements are crucial for enhancing production efficiency. In my research, I examine the application of the DMAIC methodology to develop the MEP facility within the framework of lean Six Sigma. Highlighting the challenges of precast concrete production, my study details how lean management aids in efficient process design and measurement. Introducing lean Six Sigma methodology involves standardizing processes and ensuring their effective development, contributing to the facility's efficiency
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Model Calculations on the Use of Mobile and Stationary Units for Wood Pellet Production
1-8Views:491This paper presents the model calculations made for supporting the decision making of different technology alternatives. Base cases were A) use of a mobile pelletizer and B) using pellet factories at fixed locations for the production of a new product, sheep wool pellets. Calculations were made for three alternatives for each base case. The results of the model were used to examine the energy, time and cost criteria of the alternatives. Based on the given preliminaries, results of the model calculations supported the recommendation to choose case B) for further technology management and supply chain management decisions.
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Assessment of Fibre Characteristics and Suitability of Sida acuta Burm F. for Pulp and Paper Production
1-11Views:428The ever-increasing demand for paper and paper products and alarming rate of global population growth necessitates research into non-wood fibre to augment the popular wood fibres in short supply. Sida acuta obtained at two locations, samples collected from 3 areas per location. Samples of dimension 10 x 10 x 20 mm macerated in equal volumes of glacial acetic acid and 30% hydrogen peroxide at 80oC in an oven. Twenty-five whole fibres in swollen condition were measured. Derivatives of fibre dimensions viz: Runkel ratio, flexibility and slenderness were also evaluated. Pooled mean fibre length was 1.04mm, pooled fibre diameter was 25.02μm, pooled fibre lumen width was 14.69μm and fibre cell wall thickness was 5.17μm. Runkel ratio was 0.73, coefficient of suppleness (flexibility) was 60.05 while felting power (slenderness) was 42. Values obtained connote that S. acuta’s fibre morphology is good for pulping much more that its Runkel ratio (0.73) is less than 1, coefficient of suppleness (60.05) is greater than 50 and its felting power (42) is greater than 33. Specific Gravity ranged from 0.416–0.468. With reference to the above, S. acuta is fairly suitable for pulp and paper making.
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Maintenance of Electric and Hybrid Vehicles
37-46Views:854An electric car is a vehicle powered by one or more electric engines, utilizing energy stored within batteries that are rechargeable. The first register of a usable electrical vehicle dates from 1880s. A hybrid vehicle incorporates two or more different power types, including, e.g., gasoline engines and electric motor. The goal in this work is to present the overall overview of the structure of the electric, hybrid and electric-hybrid vehicles, advantages and disadvantages of these types, the main points to focus when maintaining these and the challenges involved in its production and maintenance.
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The Importance of Continuous Organizational Project Risk Management and the Value of Project Management Certificates in the Customers’ Eyes
51-68Views:1072In an increasingly complex and volatile business environment, organizational project risk management plays a critical role in determining the chances of project success. Project management has become a common tool in the hands of large organizations for executing development and improving their production cycles in a more carefully planned way. However, the future is often hard to predict, and unexpected events may occur which could have been avoided with the use of the right tools and mindset. This comprehensive research study aims to showcase the importance of continuous risk management in organizations and highlight how risk management contributes to successful project outcomes. By synthesizing information from 59 high-quality publications from Scopus and Web of Science, the research describes various risk mitigation methodologies used across diverse fields, and explores potential obstacles faced by project managers when executing risk management strategies. The primary research of the study builds upon a survey conducted with 181 experienced project managers across various industries to gain deeper insights into their risk management approaches and the constraints they may encounter. Additionally, the study seeks to analyse the value of obtaining project management certificates in relationship with led projects’ length and budget. Employing SPSS, the research presents descriptive statistics, regression, and correlation calculations to further analyse the data gathered. The aim of the research is to draw attention to the significance of continuous risk management, propose effective methodologies, identify and mitigate potential challenges, and shed light on the potential benefits of having certifications in the field of project management. This study aims to present valuable knowledge for both researchers and organizations striving to better understand the field of project risk management strategies through the systematic literature review and quantitative research results presented.
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Research of titration curves of red mud samples
270-276Views:224The aluminium demand is increasing worldwide, so the amount of red mud, which produced during the production of aluminium, is constantly increasing, also. The researching of the economical processing of the byproduct has been under way for a long time, but the industrial implementation of recovery technology, that is suitable in all aspects, has not yet been realized. The use of by-products, in addition to reduce the risk of contamination of environmental elements, may be useful for the recovery of valuable metals, which contained therein.
