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  • Combustors with Low Emission Levels for Aero Gas Turbine Engines
    503-514
    Views:
    411

    The aircrafts are responsible for emitting several types of pollutants, especially the pollutants in the form of NOX, CO2, CO, UHC, SOX and Particulate Matter PM (smoke/soot). The impact of aviation emissions on the global is well known, where these emissions modify the chemical and microphysical properties of the atmosphere resulting in changes of earth’s climate system, which can ultimate in critical changes in our planet fragile ecosystem, also the pollutants produced by aircraft engines cause many health problems. This is why the International Civil Aviation Organisation (ICAO) is seriously seeking to control the emission levels by issuing new standards during the successive meetings of the Committee on Aviation Environmental Protection CAEP (CAEP/01 in 1986, CAEP/2, CAEP/4, CAEP/6, CAEP/8, etc). The new regulations include more stringent standards aimed to reduce emission levels, this led to increased interest in low emission technologies. In this paper, a comprehensive review of low emissions combustion technologies for modern aero gas turbines is represented. The current low emission technologies include the high Technologies Readiness Level (TRL) including RQL, TAPS, DAC and LDI. Also, there are advanced technologies at lower TRL including LPP, ASC and VGC.

  • Examination of the Relationship between Renewable Energy and Economic Performance
    234-243
    Views:
    206

    Many countries are making considerable efforts to achieve solutions to environmental problems that we face today and developing renewable energy resources is one of the potential long-term solutions that constitute an absolute priority from a sustainable development perspective. The usage of renewable energy is one of the critical future challenges to reduce greenhouse gas emission and decrease energy dependency at the same time. Thus, replacing traditional energy sources with renewable ones, like Hydropower and wind power to produce electricity instead of fossil fuel. The objective of this study is to find a relationship between renewable energy consumption, macroeconomic factors, and the environment. There is a reliable and significant (at 1% significant level) association between REC with GHG and GDP and a relatively strong association with EC.

  • The Global Electric Car Industry and the Related Indirect Emission
    Views:
    551

    Our planet tries to create a more environmental friendly transport. Related to the car purchases we can determine the consumers’ attitudes have changed in the last years and we can say that the electric cars have become one of the most significant participants in the industry. In one of his investigations Christopher Buchal realised electric cars can burden the environment with more than 11-28% than the avarage engine cars. It is possible if we make difference between direct and indirect emission, because the direct emission of the electric cars is zero, but the indirect emission can be really high related to the power generation. My goal is giving a real picture about the electric car industry and presenting my suggestions for the future.

  • Strategies and Effects of LEDS (Low Emission Development Strategy) in Fortaleza, Brazil
    110-121
    Views:
    179

    When it comes to climate change, the built environment, together with transport, and waste and water management play a significant role as Greenhouse Gases (GHG) emitting sectors, reflecting the strong need to address such issues by local governments. A notable action that has been taken in this regard is the Urban Low Emission Development Strategies (Urban LEDS), which consists of a project implemented by the UN-Habitat and the International Council for Local Environmental Initiatives (ICLEI) that selected eight model cities and twenty-one satellite cities around the world and aims to support integrated and ambitious climate action, encouraging low-carbon efforts in emerging economies through the collaboration among them. In addition, eight European cities also participated in the project in its first phase, contributing with their expertise and experience with climate change mitigation. Since 2012, the city of Fortaleza in Brazil is a model city of the Urban LEDS project and it has sustainably integrated and developed many projects, making it a more resilient city, stimulating its economic growth and improving its quality of life. This paper aims to present the milestones that Fortaleza has already met within Urban LEDS and its main priorities in the next years, identifying best practices in three European cities (Copenhagen, Zagreb and Hannover) that could also be implemented in its geographical, social and cultural context, as well as indicate lessons that other cities can learn from Fortaleza.

  • The Relationship Between Renewable Energy Consumption, Net Energy Import, Greenhouse Gas Emission and Human Cap
    58-71
    Views:
    169

    The 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.

  • Connection Between Human Excreta and Global Warming
    139-154
    Views:
    199

    Our study would like to draw attention to an insufficiently investigated question: how human excreta and its different treatment methods are related to climate change. Human excreta is part of the biological cycle. Its CO2 content gets released to the atmosphere to some degree according to the treatment methods used. 40 55% of faeces’ and 11-17% of urine’s dry matter content is carbon (in the form of organic compounds). According to this, approximately 21-57 g/person carbon bound in organic compounds is produced daily, which means an emission of 58-183 million tons of carbon in the world annually in the form of human excreta. The environmental load of the widely spread flush toilet based water infrastructure is significant. However, neither the degree of CO2 emission caused by collection and treatment of waste water, nor wasting of organic and nutrient content of excreta are properly studied. Our study highlights the emission of CO2 caused by the energy demand of sewage water collection and treatment, by the oxidation of organic compounds of human excreta and by burning of methane produced as a result of anaerobic treatment of waste water sludge. Finally the possibility of utilization of human excreta by direct composting is presented, which technology has not significantly spread in the world yet.

  • Was UEFA’S Goal of an Environmentally Friendly Euro 2020/21 a Success?
    152-164
    Views:
    623

    The football Euro 2020/21 has been said to be more environmentally friendly, as it was spread all over Europe, thus no new stadiums needed to be built. On the other hand, more traveling became necessary. How does these effects behave with each other? Was the attempt to reduce emissions successful?      
    This paper seeks to compare the goals for UEFA 2020/21 for environmental friendliness and its success. A mixed research strategy was adopted in this paper where qualitative analysis was done on existing literature review and also quantitative approach where assumptions were drawn from literature review to estimate the environmental impact. This paper found that UEFA's initial estimate of 425,000 tons of carbon dioxide emissions in traveling for the Euro Cup 2020 was a bit higher than the actual amount of carbon emissions from our calculation of 143,531 tons. What stands out is that its findings agree with UEFA's estimate that Euro Cup 2020 emissions were lower than that of 2016 which emitted 517,000 tons of carbon dioxide for traveling. This gives a greater reason to conclude that UEFA met its goal of reducing carbon emissions. The overall carbon dioxide emissions in traveling and constructing stages were 1,275,988 tons in Euro Cup 2020 and 2,803,000 tons in Euro Cup 2016. This further affirms the overall carbon dioxide emission reduction by half in Euro Cup 2020 as compared to Euro 2016. From our findings, we can conclude that the Euro Cup 2020 indeed succeeded in reducing overall carbon dioxide emissions by half. Despite the success, this paper views that the carbon emissions are still high for a single event and hence there is room for reduction of carbon emissions to lower levels as possible. we can conclude that the Euro Cup 2020 indeed succeeded in reducing overall carbon dioxide emissions by half. Despite the success, this paper views that the carbon emissions are still high for a single event and hence there is room for reduction of carbon emissions to lower levels as possible. we can conclude that the Euro Cup 2020 indeed succeeded in reducing overall carbon dioxide emissions by half. Despite the success, this paper views that the carbon emissions are still high for a single event and hence there is room for reduction of carbon emissions to lower levels as possible.

     

  • Optimizing the combustion processes of a small scale solid fuel-fired boiler
    358-369
    Views:
    144

    Over the last decade, the public has been paying increasing attention to reducing greenhouse gas and acid rain emissions and reducing particulate matter, which is extremely harmful to health and the environment. To improve air quality, the European Commission has achieved a range of measures to reduce air pollutant emissions in the transport, heat and electricity, industrial and agricultural sectors. In Hungary, the amount of gas and solid air pollutants from solid fuel combustion used by the public during the heating season represents a significant percentage of the total amount present in the atmosphere. In 2016, taking into the total emission, the 29% of CO2 emissions; 85% of CO emissions; 75% of the particulate matter emissions and 21% of the NOx emissions were derived from households. It follows that the improvement of air quality can also be achieved by controlling the emissions of solid fuel combustion plants. During our research we aimed to optimize the operation of a newly purchased TOTYA S18 boiler and a pilot pellet boiler. Operating the boilers in the correct mode minimizes air pollutant emissions, and the greater part of the heat generated is actually turns to heating the home, as with poor settings, a lot of heat leaves through the chimney. The data obtained during the tests can also be used to determine whether the boilers comply with the emission values set out in Commission Regulation (EU) 2015/1185.

  • Production of Liquid Hydrocarbons from Plastic Wastes
    345-350
    Views:
    146

    Thermal pyrolysis of HDPE, LDPE, PP and PS plastic wastes were performed in a batch reactor and the yields of pyrolysis oils and liquid transportation fuels prepared by atmospheric distillation were determined. The gasoline fractions were tested in a traditional spark-ignition engine without any modifications or fuel blending. Fuel consumption and exhaust gas emission (NOx, CO) were measured and compared to a commercial fuel (RON = 95). PS generated 70.5% gasoline range hydrocarbons from the solid waste, followed by PP with 42.1%, LDPE with 40.8% and HDPE with 37.3%. The fuel consumption was reduced by 9.1-9.4% in the case of PS compared to reference measurement. Reduction in fuel consumption was noticeable at HDPE, LDPE and PP as well. PS gasoline decreased by 91-96%, while HDPE, LDPE and PP more likely increased the CO emission of the engine compared to commercial gasoline. The results show that pyrolysis of plastic wastes is a promising method to generate value added liquid transportation fuels and reduce the footprint of waste accumulation in landfills.

  • The Use of Additive Manufacturing for Wind Tunnel Simulations
    62-71
    Views:
    154

    The current economical situation requires aircraft operators to start organizing their  activity in the direction of carbon neutrality using innovative solutions.

    The goal of present study is to desing a brand new wingtip device using 3D printing which helps reducing aerodynamical drag, leading to fuel efficiency and less carbon emission with its innovative shape.

  • HAZ Characterization of Automotive DP Steels by Physical Simulation
    478-487
    Views:
    191

    DP steels were extensively used in the vehicles industry due to its extraordinary combined properties of strength, ductility, formability and weldability which contributed great significance in reducing strength to weight ratio and CO2 emission. High strength steel i.e. DP steels (3 different grades) were experimentally investigated and thermophysically simulated using Gleeble 3500 simulator to determine softening and hardening in heat affected zone. Samples were heated to different peak temperatures (1350 °C, 950 °C, 775 °C and 650 °C), two cooling time (t8.5/5 = 5 s and 30 s) and Rykalin 2D model were selected. The hardness and microstructure of the specimens were tested and analysed. For longer cooling time (t8.5/5= 30 s), we observed that softening occurs in all grade of investigated DP steels to all sub-regions. But for shorter cooling time i.e. t8.5/5= 5 s the softening is higher in intercritical HAZ compared to other sub-regions for all the types of DP steel with short cooling time (t8.5/5 = 5 s). However, the hardening zone in the CGHAZ occurs when Tmax is 1350 ºC for DP600, DP800 & DP1000 steels but it is more prominent in DP800 as compared to others two steel grade.

  • The Analysis of the Composition of Greywater and the Effectiveness of a Household Greywater Treatment System
    142-150
    Views:
    183

    The purpose of the current study is to give comparable results to previous and further examinations concerning the quality of household generated greywater and to determine the effectiveness of a household wastewater treatment system treating only household generated greywater. Data for this study were collected from a household which avoids the production of black water at the source by using dry toilet. Water samples were collected from January 2017 until May 2017, altogether seven times. Samples were taken from 3 different places: (i) potable water from the kitchen tap, (ii) greywater sample from the first sewage tank of the household sewage treatment system and (iii) greywater sample from the fourth (last) sewage tank of the household sewage treatment system. A total of 16 physical, chemical and microbiological parameters were measured in the laboratory using the valid standard methods in each cases. The results of this investigation show that separating black water from greywater at the source by using dry toilet may produce considerably smaller environmental load. Lower emission values stems from the lower organic matter, nitrogen and phosphorus content of greywater.

  • Future Power Plant Portfolio Analysis from the Point of View of Minimum Cost and Emission Optimization
    61-77
    Views:
    52

    The article examines the expected composition of the power plant portfolio in Hungary by 2030. The indicators considered are the life-cycle unit costs (LCOE) and the life-cycle specific carbon dioxide emissions (LCA(CO2)) of the power plant types. The minimum of these two indicators, as objective functions, is determined by a linear programming method for the power plant portfolio. The results show that the LCOE minimum for the power plant portfolios in 2030 is worse in absolute terms and better in specific terms than in 2021. In both absolute and specific terms, the LCA(CO2) minimum is more favourable in 2021. These results are met under the thirty and twenty-five percent electricity import scenarios. With twenty percent imports, the absolute values are worse and the specific values are better for both indicators. On the other hand, the results of the calculations for 2030 fall short of the 2030 Agenda of the Institute for a Green Transition. This is due to the delay in commissioning a new nuclear power plant and the transformation of industry with increasing electricity demand. For the portfolios under review, a minimum of thirty percent of domestic generation from renewable sources is met. This contributes significantly to the European Union's ambition for the sector to be net greenhouse gas-free by 2050.

  • The Alternative Use of Straw
    331-343
    Views:
    140

    The problem addressed in this work is to examine the feasibility of using straw in innovative and alternative ways, focusing on aspects of cost sensitivity in subject areas of building investment and energy compsumption. I analysed the energy efficient performance of a straw bale building and compared that with those of a conventional construction, a newly-constracted building and a passive house. In my study I assessed the figures of costs of emboided energy, primary energy consumption and carbon dioxide emission. I made calculations in terms of energy costs for a lifespan of 50 years. Considering that straw-bale construction uses an excellent and sustainable insulation material, its energy use is by 25.38% less than that of conventional construction.

  • Climate-Neutral Energy Production - Prospects in Hungary in 2024
    53-60
    Views:
    79

    In order to protect our planet's climate, it is important to reduce humanity's carbon dioxide emissions significantly. The energy sector is one of the most polluting industries, but the rapid spread of renewable energy sources over the past 20 years can significantly contribute to the reduction of carbon dioxide emissions. The study examined which energy sources are used to produce electricity in Hungary, and how the proportion of renewable energy has developed in recent years compared to more polluting energy production methods. There is a strong negative exponential relationship between the share of renewable energy and the carbon dioxide emissions of the energy sector, based on which the carbon dioxide emissions of the energy sector can be significantly reduced by increasing the share of renewable energy. A forecast was made for the renewable share based on past data and the revised state of the National Energy and Climate Plan in 2023, and a linear forecast was made for the energy sector's emissions. There is a strong exponential relationship between the data series. Both models examined in the study had strong explanatory power, but neither model supports the possibility of climate-neutral energy production by 2030.

  • Analysis of the Causes and Effects of Noise from Rail Transport
    116-130
    Views:
    119

    Noise emissions from rail transport are a major concern, as they affect both the environment and people's health and quality of life. Among the many sources of noise emissions, rail vehicles and infrastructure are a major factor. With regard to rail noise emissions, it can be concluded that noise effects are influenced by a number of factors. These factors include train speed, track condition, traction technology and the noise abatement methods used. The negative effects of noise exposure include sleep disturbance, stress and mental health deterioration. It also affects the quality of life of people in urban areas and property prices. It should be emphasised that reducing noise emissions from rail transport is key to creating a healthier and more sustainable urban environment. To achieve this, it is important to use modern noise abatement technologies, improve infrastructure and implement noise abatement actions effectively. Transport authorities and railway companies should work together to achieve a more noise-free rail transport, to improve people's quality of life and to protect the environment.

  • Current Challenges in the Regulation of CO2 Emission of Road Vehicles
    738-742
    Views:
    222

    Today, as part of the fight against climate change, regulations on greenhouse gas emissions are gaining significantly higher attention. Our work focuses on the European Union legislation on carbon dioxide emissions from road vehicles, with special emphasis on the target values. Current changes in CO2 measurement methods, as important issues of the regulations, are also reviewed within this article.

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