Current and Future Trends of Refrigerants Development

In this chapter is addressed the thematic of refrigerants: its historical evolution; properties; legislation applied in the area and future trends. The first refrigerant being marketed on a large scale was ethyl ether (R610), in 1834. Since then, the evolution of the utilized refrigerants was stimulated, initially due to constructive issues in the refrigeration system and later to environmental issues. This evolution may be divided into four generations: 1st use of any fluid that worked; 2nd safety and durability of the equipment; 3rd ozone layer protection and 4th increase of global warming concerns. During the process of evolution many refrigerants were tested to understanding of their properties. Currently, environmental concerns are taken as guide in the search for new refrigerants. The most promising refrigerants to be used in future are the HFEs, HFOs and HFCs with low-GWP, natural refrigerants and blends between (HCs/HFCs and HFCs/HFOs) refrigerants.

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Current and Future Trends of Refrigerants Development

Handbook of Research on Advances and Applications in Refrigeration Systems and Technologies - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-4666-8398-3.ch006 ◽

2015 ◽

pp. 207-259

Author(s):

M. V. Duarte ◽

L. C. Pires ◽

P. D. Silva ◽

P. D. Gaspar

Keyword(s):

Global Warming ◽

Ethyl Ether ◽

Large Scale ◽

Environmental Issues ◽

Ozone Layer ◽

Environmental Concerns ◽

Historical Evolution ◽

Future Trends ◽

Refrigeration System

In this chapter is addressed the thematic of refrigerants: its historical evolution; properties; legislation applied in the area and future trends. The first refrigerant being marketed on a large scale was ethyl ether (R610), in 1834. Since then, the evolution of the utilized refrigerants was stimulated, initially due to constructive issues in the refrigeration system and later to environmental issues. This evolution may be divided into four generations: 1st use of any fluid that worked; 2nd safety and durability of the equipment; 3rd ozone layer protection and 4th increase of global warming concerns. During the process of evolution many refrigerants were tested to understanding of their properties. Currently, environmental concerns are taken as guide in the search for new refrigerants. The most promising refrigerants to be used in future are the HFEs, HFOs and HFCs with low-GWP, natural refrigerants and blends between (HCs/HFCs and HFCs/HFOs) refrigerants.

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Prospective teachers and secondary students’ ideas on global environmental issues: Contradictions or similarities

International Journal of Learning and Teaching ◽

10.18844/ijlt.v10i1.3141 ◽

2018 ◽

Vol 10 (1) ◽

pp. 13

Author(s):

Filiz Kabapınar ◽

Candan Cengiz ◽

Oya Aglarci

Keyword(s):

Global Warming ◽

Environmental Education ◽

Secondary Students ◽

Prospective Teachers ◽

Greenhouse Effect ◽

Environmental Issues ◽

Ozone Layer ◽

Ozone Layer Depletion ◽

Global Environmental ◽

Global Environmental Issues

The present study aims to investigate prospective teachers’ (PTs’) and secondary students’ (SSs’) ideas related to environmental issues. A case study design was adopted in this study. SSs (n = 100) who received instruction on environmental issues and PTs (n = 150) who attended courses concerning environmental education were participated in this study. An open-ended questionnaire was designed and used as a data collection tool. Written answers of the participants were analysed in ideographic terms. The results of the study showed that the PTs held a range of alternative ideas similar to SSs. They both linked environmental problems which were irrelevant with cause–effect chain. Yet, PTs provided a more scientific definitions regarding greenhouse effect, global warming and ozone layer depletion as compared to SSs. Keywords: Global environmental issues, prospective teachers, secondary students, environmental education, greenhouse effect, global warming, ozone layer depletion.

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Global Environmental Issues: Responses from Japan

Japanese Journal of Political Science ◽

10.1017/s1468109904001306 ◽

2004 ◽

Vol 5 (1) ◽

pp. 23-50 ◽

Cited By ~ 2

Author(s):

LYDIA N. YU-JOSE

Keyword(s):

Global Warming ◽

United Nations ◽

Environmental Issues ◽

Leadership Role ◽

Hazardous Wastes ◽

Environmental Concerns ◽

Basel Convention ◽

Global Environmental ◽

Policy Statements ◽

Global Environmental Issues

The timing of the Japanese Government's acceptance of the United Nations multilateral treaties governing several environmental concerns indicates Japan's priorities: biodiversity, global warming, and depletion of the ozone layer. Banning transboundary movement of hazardous wastes is the least prioritized, as indicated by Japan's failure to accept the Ban Amendment to the Basel Convention. The Japanese Environment Agency's policy statements and budget allocations between 1985 and 2000, as well as other official statements and programs, likewise indicate the same priorities. Moreover, of the three priorities, global warming is the top.Japan, which has been looking for a niche in world leadership, has found it in global warming concerns. However, it would be hard for it to maintain a leadership role in global environmental concerns if it would not be able to play a proactive role in the more technologically, economically and politically difficult task of banning transboundary movement of hazardous wastes.

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OPTIMIZATION OF WASTAGE PART OF COMPUTER SYSTEMSBY EFFECTIVE ACHIEVEMENT OF GREEN COMPUTING

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v3.i9se.2015.3146 ◽

2015 ◽

Vol 3 (9SE) ◽

pp. 1-2

Author(s):

Nirmala Gupta

Keyword(s):

Energy Efficiency ◽

Global Warming ◽

Environmental Issues ◽

Ozone Layer ◽

Green Computing ◽

Green House

The environmental issues concerned with using computers because it is not possible to decrease the usage of computer.Our earth is also passing through the global warming, Green house effect and the ozone layer is becoming thin. Today Computers are widely used throughout the globe from any kind of organization to all over the place.The goals are to reduce the use of dangerous materials, maximize energy efficiency during the product's lifetime, and promote recyclability or biodegradability of useless products and factory waste. It is to be known that as the economy expands, the demand for computing devices increases as business and individuals seek faster way of doing things –‟TheComputing way‟.

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UJI EKSPERIMENTAL MESIN PENDINGIN BERPENDINGIN AIR DENGAN MENGGUNAKAN REFRIGERAN R22 DAN REFRIGERAN R407C

POROS ◽

10.24912/poros.v12i2.570 ◽

2014 ◽

Vol 12 (2) ◽

pp. 165

Author(s):

Terry Gunawan ◽

Harto Tanujaya ◽

Asrul Aziz

Keyword(s):

Global Warming ◽

Environmental Problems ◽

Ozone Layer ◽

Test Results ◽

Refrigeration System ◽

Human Needs ◽

Processing Data ◽

Refrigeration Capacity ◽

Compressor Power ◽

Test Result

Abstract: The human needs of refrigeration system have created a tool that called a refrigerator. Refrigerator/cooling machine have a component which have a very important role in the refrigeration system that is refrigerant. Refrigerant that still widely used for cooling machine until now is the refrigerant R22. Using R22 refrigerant can cause environmental problems such as damage to the ozone layer and global warming. Therefore, it needs a substitution refrigerant which is more friendly for environment which one of them is R407C refrigerant. In this study, using a cooling machine with water- cooled condenser and the flowrate that use is 20 L/h, 40 L/h, 80 L/h and 120 L/h. The variables that measured in this study is temperature (T1, T2, T3, T4, T10, T11), pressure (P1, P2, P3, P4), and ampere. This study aims to get the test results using refrigerants R22 and R407C. The processing data of the test result include refrigeration capacity, compressor power and COP. The results obtained have that cooling machine which use R22 refrigerants have a better COP than using R407C refrigerant. This is happen because the power needed by the compressor to compress R407C refrigerant to flow in the system is greater than using R22 refrigerant.

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The Environmental Concerns of Food Ecopreneurs

Sustainability ◽

10.3390/su13116211 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6211

Author(s):

Joacim Rosenlund

Keyword(s):

Empirical Research ◽

Large Scale ◽

Short Communication ◽

Environmental Issues ◽

Environmental Concerns ◽

Distinct Form ◽

The Everyday

This short communication highlights ecopreneurship as a distinct form of entrepreneurship. Excerpts from interviews with ecopreneurs were analyzed using the literature of ecopreneurship and passion. Ecopreneurs want to solve environmental issues that are large scale and often impossible to solve. The passion for the environment helps them through the everyday entrepreneurial struggles and keeps them on their existential odysseys. This empirical research shows a way forward for studies of entrepreneurship-based environmental concerns.

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The Potential of Photoelectrochemical Carbon Sinks

10.26434/chemrxiv.6231140.v2 ◽

2018 ◽

Author(s):

Matthias May ◽

Kira Rehfeld

Keyword(s):

Global Warming ◽

High Temperature ◽

Greenhouse Gas ◽

Large Scale ◽

High Efficiency ◽

Carbon Sink ◽

Solar Fuels ◽

Negative Emissions ◽

Viable Approach ◽

Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO2 from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO2 reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.

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The Potential of Photoelectrochemical Carbon Sinks

10.26434/chemrxiv.6231140 ◽

2018 ◽

Author(s):

Matthias May ◽

Kira Rehfeld

Keyword(s):

Global Warming ◽

High Temperature ◽

Greenhouse Gas ◽

Large Scale ◽

High Efficiency ◽

Carbon Sink ◽

Solar Fuels ◽

Negative Emissions ◽

Viable Approach ◽

Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO2 from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO2 reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.

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New HFC/HFO Blends as Refrigerants for the Vapor-Compression Refrigeration System (VCRS)

Energies ◽

10.3390/en14040946 ◽

2021 ◽

Vol 14 (4) ◽

pp. 946

Author(s):

Bartosz Gil ◽

Anna Szczepanowska ◽

Sabina Rosiek

Keyword(s):

Global Warming ◽

Global Warming Potential ◽

Mass Fraction ◽

Vapor Compression ◽

Refrigeration System ◽

Operational Parameters ◽

Vapor Compression Refrigeration ◽

Low Global Warming Potential ◽

Triangular Design

In this work, which is related to the current European Parliament Regulation on restrictions affecting refrigeration, four new three-component refrigerants have been proposed; all were created using low Global Warming Potential(GWP) synthetic and natural refrigerants. The considered mixtures consisted of R32, R41, R161, R152a, R1234ze (E), R1234yf, R1243zf, and RE170. These mixtures were theoretically tested with a 10% step in mass fraction using a triangular design. The analysis covered two theoretical cooling cycles at evaporating temperatures of 0 and −30 °C, and a 30 °C constant condensing temperature. The final stage of the work was the determination of the best mixture compositions by thermodynamic and operational parameters. R1234yf–R152a–RE170 with a weight share of 0.1/0.5/0.4 was determined to be the optimal mixture for potentially replacing the existing refrigerants.

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