Browse
Subjects
Records with Subject: Environment
Showing records 1228 to 1252 of 3421. [First] Page: 1 47 48 49 50 51 52 53 54 55 Last
Enhanced Cooling of LED Filament Bulbs Using an Embedded Tri-Needle/Ring Ionic Wind Device
Chunlin Xu, Huai Zheng, Jie Liu, Jingcao Chu, Xiaoliang Zeng, Rong Sun, Sheng Liu.
March 27, 2023 (v1)
Subject: Environment
Keywords: discharge current, electrode, heat dissipation, inception voltage, junction temperature, light efficiency.
Improving the heat dissipation ability for light-emitting diode (LED) filament bulb is very difficult. A tri-needle/ring ionic wind generator was developed to improve the heat dissipation condition of bulbs. The operation characteristics of the ionic wind generator, such as the electrode gap, inception voltage, and discharge current with regard to the operation voltage, were studied by experiments. The ionic wind velocity within the bulb was investigated under different electrode gaps and applied voltages. The temperature drop achieved by the ionic was were tested with the consideration of many operation parameters for analysis. The experiments showed that ionic wind can provide efficient and stable cooling effect for LED filament bulbs. The temperature drop of LED junction can reach 30 °C at best. Good stability and adjustability of the ionic wind generator were demonstrated by tracing the temperature history of LED filaments in long-term tests. Finally, the light efficiency of LED fi... [more]
Reduction in Operating Costs and Environmental Impact Consisting in the Modernization of the Low-Power Cylindrical Wood Chipper Power Unit by Using Alternative Fuel
Łukasz Warguła, Mateusz Kukla, Piotr Krawiec, Bartosz Wieczorek.
March 27, 2023 (v1)
Subject: Environment
Keywords: Alternative Fuels, fuel consumption, LPG, mass flow rate, non-road small engine, volumetric flow rate, wood chipper.
Alternative fuel within the meaning of Directive 2014/94/EU is, among others, LPG (liquefied petroleum gas), characterized by a lower purchase cost and lower emissions of toxic exhaust compounds in comparison to the combustion of classic gasoline. In wood chippers, intended for chopping branches, with low-power internal combustion engines that meet the emission standards in force in 2019 in the European Union, in accordance with Regulation 2016/1628/EU, carburetor fuel supply systems are commonly used. Innovative trends in the development of these drives are: electronic fuel injection, systems supporting the adaptation of the working elements to the conditions of use and the use of alternative fuels. The first two solutions significantly affect the cost of purchasing a power unit or modernizing it. The authors of this article indicate, as a beneficial alternative, a cheap (EUR 105) possibility of modernizing the carburetor fuel supply system. It is based on a modification that will all... [more]
Modeling of Humidity in Passenger Cars Equipped with Mechanical Ventilation
Katarzyna Gładyszewska-Fiedoruk, Tomasz Janusz Teleszewski.
March 27, 2023 (v1)
Subject: Environment
Keywords: humidity, indoor air quality, indoor environmental quality, Modelling, moisture.
This paper presents research on humidity in a passenger car cabin with the use of supply ventilation without cooling the air. Based on the tests carried out and the humidity balance in the car, a model was developed for changing the humidity in the passenger car cabin as a function of time. The study of thermohumid conditions was carried out in two passenger cars. During the tests, the heating and cooling functions were turned off. The relative humidity and temperature were measured outside the car before and after driving the car and in the supply air duct and inside the passenger car cabin while driving the car. The tests were carried out for an average temperature range from 20 to 42.9 °C. In order to develop a model of humidity changes as a function of time, a humidity balance was prepared. Human-generated humidity in the car cabin depends mainly on the temperature inside the car and the age of the person and can range from 20 to 180 g/(h × person) for an adult in the temperature r... [more]
Thermal Comfort and Energy Use with Local Heaters
Jan Kaczmarczyk, Joanna Ferdyn-Grygierek.
March 27, 2023 (v1)
Subject: Environment
Keywords: energy demand, energy saving, local heating, thermal comfort.
This paper presents the investigation of a local heating system consisting of three heating mats incorporated within a sedentary workplace. Thermal comfort and individual power settings for the heating mats were studied in experiments with 41 human subjects. Experiments were performed in a climate chamber at two operative temperatures: 16 and 18 °C. Results showed that local heating systems improved occupants’ comfort and were able to create acceptable thermal conditions under both temperatures. The power settings identified were used to study the applicability of heating mats in an industrial hall. Multi-variant analysis of energy consumption for heating was carried out using an ESP-r (Environmental Systems Performance−Research) simulation program. The analysis results demonstrate that in some cases, the installation of local heating mats in industrial halls may reduce energy usage compared to having to heat the entire hall. However, the benefits depend on numerous parameters. Local h... [more]
Phytoremediation—From Environment Cleaning to Energy Generation—Current Status and Future Perspectives
Anna Grzegórska, Piotr Rybarczyk, Andrzej Rogala, Dawid Zabrocki.
March 27, 2023 (v1)
Subject: Environment
Keywords: bioenergy, metal recovery, phytoremediation, plant utilization, soil contaminants.
Phytoremediation is a technology based on the use of green plants to remove, relocate, deactivate, or destroy harmful environmental pollutants such as heavy metals, radionuclides, hydrocarbons, and pharmaceuticals. Under the general term of phytoremediation, several processes with distinctively different mechanisms of action are hidden. In this paper, the most popular modes of phytoremediation are described and discussed. A broad but concise review of available literature research with respect to the dominant process mechanism is provided. Moreover, methods of plant biomass utilization after harvesting, with particular regard to possibilities of “bio-ore” processing for metal recovery, or using energy crops as a valuable source for bio-energy production (bio-gas, bio-ethanol, bio-oil) are analyzed. Additionally, obstacles hindering the commercialization of phytoremediation are presented and discussed together with an indication of future research trends.
Causality between CO2 Emissions and Stock Markets
Chia-Lin Chang, Jukka Ilomäki, Hannu Laurila, Michael McAleer.
March 27, 2023 (v1)
Subject: Environment
Keywords: carbon emissions, climate change, fossil fuels, global warming, Granger causality, predictability, sophisticated financial markets, stock market returns.
It is generally accepted in the scientific community that carbon dioxide (CO2) emissions, which lead to global warming, arise from using fossil fuels, namely coal, oil and gas, as energy sources. Consequently, alleviating the effects of global warming and climate change necessitates substantial reductions in the use of fossil fuel energy. This paper uses a financial market-based approach to investigate whether positive stock returns cause changes in CO2 emissions, or vice-versa, based on the Granger causality test to determine cause and effect, or leader and follower. If Granger causality can be determined in any direction, this will enable a clear directional statement regarding temporal predictability between stock returns and CO2 emissions. The empirical data include annual CO2 emissions from fuel combustion of the three main fossil energy sources, namely coal, oil and gas, based on 18 countries with sophisticated financial markets that are in the Morgan Stanley Capital Internationa... [more]
A Review of the Relation between Household Indoor Temperature and Health Outcomes
Fátima Lima, Paula Ferreira, Vítor Leal.
March 27, 2023 (v1)
Subject: Environment
Keywords: buildings, elderly, fuel poverty, health, indoor environment, indoor temperature.
This paper provides a review of research that addresses the relationship between indoor temperatures and health outcomes, taking into consideration studies that focus heat or cold exposure within the household context. It aims to extend previous research by considering both indoor temperatures from existing housing, and empirical studies that focus on energy efficiency measures and subsequent health impacts. To achieve this aim, a literature review was undertaken, combining engineering and health databases. The review established that, overall, inadequate indoor temperatures are associated with poor health status, whereas energy efficiency measures have been associated to improved indoor temperatures and occupant’s health namely regarding cardiovascular, respiratory and mental health disorders. These health conditions are among the most prevalent non-communicable diseases (NCD). The review also highlighted the need for more empirical studies with an extended timeframe to deal with clim... [more]
Life Cycle Assessment of Electric Vehicle Batteries: An Overview of Recent Literature
Andrea Temporelli, Maria Leonor Carvalho, Pierpaolo Girardi.
March 27, 2023 (v1)
Subject: Environment
Keywords: battery electric vehicles, environmental impacts, life cycle assessment, review.
In electric and hybrid vehicles Life Cycle Assessments (LCAs), batteries play a central role and are in the spotlight of scientific community and public opinion. Automotive batteries constitute, together with the powertrain, the main differences between electric vehicles and internal combustion engine vehicles. For this reason, many decision makers and researchers wondered whether energy and environmental impacts from batteries production, can exceed the benefits generated during the vehicle’s use phase. In this framework, the purpose of the present literature review is to understand how large and variable the main impacts are due to automotive batteries’ life cycle, with particular attention to climate change impacts, and to support researchers with some methodological suggestions in the field of automotive batteries’ LCA. The results show that there is high variability in environmental impact assessment; CO2eq emissions per kWh of battery capacity range from 50 to 313 g CO2eq/kWh. Ne... [more]
Complete Data Inventory of a Geothermal Power Plant for Robust Cradle-to-Grave Life Cycle Assessment Results
Lorenzo Tosti, Nicola Ferrara, Riccardo Basosi, Maria Laura Parisi.
March 27, 2023 (v1)
Subject: Environment
Keywords: Bagnore power plant, flash technology, geothermal energy, life cycle assessment, pedigree matrix.
Technologies to produce electric energy from renewable geothermal source are gaining increasing attention, due to their ability to provide a stable output suitable for baseload production. Performing life cycle assessment (LCA) of geothermal systems has become essential to evaluate their environmental performance. However, so far, no documented nor reliable information has been made available for developing robust LCA studies. This work provides a comprehensive inventory of the Italian Bagnore geothermal power plants system. The inventory is based exclusively on primary data, accounting for every life cycle stage of the system. Data quality was assessed by means of a pedigree matrix. The calculated LCA results showed, with an overall low level of uncertainty (2−3%), that the commissioning and operational phases accounted for more than 95% of the environmental profile. Direct emissions to atmosphere were shown to be the major environmental impact, particularly those released during the... [more]
Potential Effects of Vacuum Insulating Glazing Application for Reducing Greenhouse Gas Emission (GHGE) from Apartment Buildings in the Korean Capital Region
Sanghoon Baek, Sangchul Kim.
March 27, 2023 (v1)
Subject: Environment
Keywords: apartment buildings, greenhouse gas emissions, insulating glazing (IG), vacuum insulating glazing (VIG).
Korea has set a goal of reducing greenhouse gas emissions (GHGEs) to levels 37% below the “business as usual (BAU)” level by 2030, and the building sector, in particular, aims to reduce GHGEs by 45,000,000-ton CO2-eq by 2020. In order to reach this goal, it is crucial to reduce GHGEs that result from energy consumption in apartment buildings, which account for approximately 65% of all buildings in the capital region where the population is concentrated. Moreover, as apartment buildings not only have high window-to wall area ratios, but also use insulating glazing (IG) with low thermal performance, an advanced window system with low heat transmittance (U-value), such as a concrete structure, is necessary for effective GHGE reduction. Therefore, this study aims to evaluate the GHGE reduction effects from replacing existing IG vacuum insulating glazing (VIG) with low U-values in the apartment housing located in the capital region. The analysis revealed the possibility of a GHGE reduction... [more]
Fuzzy Model for Selecting a Form of Use Alternative for a Historic Building to be Subjected to Adaptive Reuse
Małgorzata Fedorczak-Cisak, Alicja Kowalska-Koczwara, Filip Pachla, Elżbieta Radziszewska-Zielina, Bartłomiej Szewczyk, Grzegorz Śladowski, Tadeusz Tatara.
March 27, 2023 (v1)
Subject: Environment
Keywords: fuzzy sets, fuzzy weighted influence non-linear gauge system—FWINGS, historical buildings, multi-criteria analysis, sustainable development, thermal comfort.
Adapting historic buildings to new, modern forms generates not only financial benefits for developers but can also allow them to survive for future generations through proper remodelling. The variety of decision criteria related to the selection of a new function of a historic building makes this problem multidimensional. Many of these criteria are interrelated and have a non-linear nature which requires a comprehensive network-based rather than a classic hierarchical approach to conducting multi-criteria analysis. A comprehensive approach taking into account the specificity of the analysed problem was proposed. The study was supported by an example of the choice of building function as part of the adaptive reuse of a historic building located in Zakopane. The following variants have been analysed: a hostel (existing state), a five-star hotel, a folk art gallery and a conference and training centre. The final rating of alternatives indicates that the hotel best meets the adopted decisi... [more]
Combining Biomass Gasification and Solid Oxid Fuel Cell for Heat and Power Generation: An Early-Stage Life Cycle Assessment
Christian Moretti, Blanca Corona, Viola Rühlin, Thomas Götz, Martin Junginger, Thomas Brunner, Ingwald Obernberger, Li Shen.
March 27, 2023 (v1)
Subject: Environment
Keywords: allocation, Biomass, CHP, gasification, LCA, multifunctionality, SOFC.
Biomass-fueled combined heat and power systems (CHPs) can potentially offer environmental benefits compared to conventional separate production technologies. This study presents the first environmental life cycle assessment (LCA) of a novel high-efficiency bio-based power (HBP) technology, which combines biomass gasification with a 199 kW solid oxide fuel cell (SOFC) to produce heat and electricity. The aim is to identify the main sources of environmental impacts and to assess the potential environmental performance compared to benchmark technologies. The use of various biomass fuels and alternative allocation methods were scrutinized. The LCA results reveal that most of the environmental impacts of the energy supplied with the HBP technology are caused by the production of the biomass fuel. This contribution is higher for pelletized than for chipped biomass. Overall, HBP technology shows better environmental performance than heat from natural gas and electricity from the German/Europe... [more]
Global Indicators of Sustainable Development: Evaluation of the Influence of the Human Development Index on Consumption and Quality of Energy
Alexei Yumashev, Beata Ślusarczyk, Sergey Kondrashev, Alexey Mikhaylov.
March 27, 2023 (v1)
Subject: Environment
Keywords: economic development, Energy, human development index, social development, Sustainability.
The article explores the impact of the quality and volume of energy consumption of the population on the human development index using a sample of a number of countries as an example. The hypothesis concerning the relationship between the amount of energy consumed, the human development index (HDI), and the environment (CO2 emissions into the atmosphere) has been verified. The study results show that the size and rating of the HDI are influenced by such factors as urbanization growth, gross domestic product (GDP), gross national income (GNI) per capita, the share of “clean” energy consumption by the population and business in total energy consumption, the level of socio-economic development, and R&D expenses. In the course of building the model, the recommendations by the United Nations (UN) and the Organization for Economic Co-operation and Development (OECD) were used. The results show that the volume of energy consumption not only affects the human development index in a particular... [more]
The Green Structure for Outdoor Places in Dry, Hot Regions and Seasons—Providing Human Thermal Comfort in Sustainable Cities
Karol Bandurski, Hanna Bandurska, Ewa Kazimierczak-Grygiel, Halina Koczyk.
March 27, 2023 (v1)
Subject: Environment
Keywords: climate change adaption, evapotranspiration, green infrastructure, green shelter, green tunnel, green wall, nature based solution, pergolas, pocket park, shade.
Hot and dry climate and air pollution is a growing problem in urban areas, and this can have an adverse impact on life and health of urban residents. One of the ways to protect people from this hazard is the use of urban green or street greenery. However, its implementation can be problematic in highly urbanized areas. This paper presents a concept of the green structure (GS), designed, and is still being developed, by Adam Kalinowski where cooling efficiency is based on the synergy of shade and evapotranspiration. The GS that could be used as street furniture, small architecture form or a public utility structure intended to protect people and objects from an adverse urban environment, at the same time providing pleasant and healthy microclimate inside. The pilot project-the first application of the GS in the urban environment-is presented and the results of short-term measurements of temperature and humidity are provided and analyzed. Moreover, a simple dynamic simulation of the GS p... [more]
The Influence of High-Rise Buildings on Pedestrian-Level Wind in Surrounding Street Canyons in an Urban Renewal Project
Tzu-Ling Huang, Chien-Yuan Kuo, Chun-Ta Tzeng, Chi-Ming Lai.
March 27, 2023 (v1)
Subject: Environment
Keywords: high-rise building, pedestrian wind environment, street canyon, urban renewal, wind-tunnel testing.
The pedestrian wind environment in a street canyon is affected by a multitude of factors, including the height and geometric shape of the surrounding buildings, the street width, the wind direction, and speed. Wind-tunnel tests were performed to determine the effects of constructing high buildings in an urban renewal project in New Taipei City, Taiwan on the pedestrian wind environments in the surrounding street canyons. The results show that replacing the original low-rise buildings with high-rise buildings could decrease the wind speed and natural ventilation potential in certain surrounding street canyons. The flow fields generated by approaching winds in various street canyons are highly complex in this practical case study. Thus, the pedestrian wind patterns in the street canyons cannot be interpreted in terms of channeling and shielding effects alone, as is typically reported in the literature.
Socio-Economic Opportunities from Miscanthus Cultivation in Marginal Land for Bioenergy
Calliope Panoutsou, David Chiaramonti.
March 27, 2023 (v1)
Subject: Environment
Keywords: Combined Heat and Power (CHP), employment, Fast Pyrolysis Biomass Oil, Greece, Italy, marginal land, Miscanthus, profit.
Substantial areas of agricultural land in south European countries are becoming increasingly marginal and being abandoned due to arid climate with prolonged summers and low rainfall. Perennial, lignocellulosic crops, such as Miscanthus, offer an outlet that couples agriculture with energy, creates employment, and increases profits from feedstock production in rural areas. This research paper follows an Input Output methodology and uses an econometric model to investigate the impact of crop yielding performance and marginal land to jobs and profit from the cultivation and supply of Miscanthus in low quality, marginal land in Italy and Greece. Two value chain cases are analysed: small scale Combined Heat and Power (CHP) and Fast Pyrolysis Bio Oil (FPBO). The cultivation of Miscanthus in both reference value chains exhibits good employment prospects, with smaller scale value chains creating more labour-intensive logistics operations. The activities can also generate substantial financial... [more]
Energy and Environmental Analysis of Single-Family Houses Located in Poland
Krzysztof Grygierek, Joanna Ferdyn-Grygierek, Anna Gumińska, Łukasz Baran, Magdalena Barwa, Kamila Czerw, Paulina Gowik, Klaudia Makselan, Klaudia Potyka, Agnes Psikuta.
March 27, 2023 (v1)
Subject: Environment
Keywords: global warming potential, heat demand, infiltration, life cycle assessment, life cycle costs, single-family house, thermal comfort.
This paper presents a comparative analysis of the carbon footprint, energy demand and life cycle costs of a model of a building located in the Central Europe climate zone. One specific example—the quantitative differences in global warming potential, life cycle costs and thermal comfort—has been shown, depending on the different construction (wood, brick) and heat sources used; traditional and energy-saving solutions have been considered. The research was carried out using the EnergyPlus simulation program for a multi-zone model of a naturally ventilated single-family house. Calculations were made for a 25-year life cycle using the standard climate data for Warsaw (Poland). The real occupancy schedule of the individual rooms was adopted and the instantaneous ventilation airflow was modeled, and its intensification due to the additional opening of windows was optimized. An estimated budget of the entire structure of the building and the heat sources was used for the cost analysis. The r... [more]
Maritime Transport in a Life Cycle Perspective: How Fuels, Vessel Types, and Operational Profiles Influence Energy Demand and Greenhouse Gas Emissions
Grusche J. Seithe, Alexandra Bonou, Dimitrios Giannopoulos, Chariklia A. Georgopoulou, Maria Founti.
March 27, 2023 (v1)
Subject: Environment
Keywords: Energy Use, Green House Gases, Heavy Fuel Oil, Life Cycle Assessment, Liquefied Natural Gas, Sustainable Transport.
A “Well-to-Propeller” Life Cycle Assessment of maritime transport was performed with a European geographical focus. Four typical types of vessels with specific operational profiles were assessed: a container vessel and a tanker (both with 2-stroke engines), a passenger roll-on/roll-off (Ro-Pax) and a cruise vessel (both with 4-stroke engines). All main engines were dual fuel operated with Heavy Fuel Oil (HFO) or Liquefied Natural Gas (LNG). Alternative onshore and offshore fuel supply chains were considered. Primary energy use and greenhouse gas emissions were assessed. Raw material extraction was found to be the most impactful life cycle stage (~90% of total energy use). Regarding greenhouse gases, liquefaction was the key issue. When transitioning from HFO to LNG, the systems were mainly influenced by a reduction in cargo capacity due to bunkering requirements and methane slip, which depends on the fuel supply chain (onshore has 64% more slip than offshore) and the engine type (4-str... [more]
Life-Cycle Assessment of the Use of Peach Pruning Residues for Electricity Generation
Jan Den Boer, Arkadiusz Dyjakon, Emilia Den Boer, Daniel García-Galindo, Techane Bosona, Girma Gebresenbet.
March 27, 2023 (v1)
Subject: Environment
Keywords: biomass-to-energy, electricity production, LCA, life cycle assessment, peach pruning residues.
Biomass residues from permanent crops might be an alternative fuel for energy generation in a local market with limited transport distances. Moreover, as activities related to CO2 reduction are of special attention in the European Union (EU), sustainable use of resources plays an important role in climate change mitigation. In this paper, a life-cycle assessment (LCA) of the integrated value chain from peach pruning residues for electricity generation is presented and compared with the common practice including the mulching process of the pruned biomass in an orchard. It was shown that biomass harvesting, chipping and its delivery to a power plant—the Pruning-to-Energy (PtE) scenario—is feasible from an environmental point of view. The total global warming potential (GWP) of this value chain was 200 kg CO2 eq.·ha−1 (or 27 kg CO2 eq.·GJ−1). In turn, the mulching and leaving of the pruned biomass in an orchard—the pruning-to-soil (PtS) scenario—is characterized by a CO2 equivalent of 236... [more]
Environmental and Economic Analysis of an Anaerobic Co-Digestion Power Plant Integrated with a Compost Plant
Sara Rajabi Hamedani, Mauro Villarini, Andrea Colantoni, Maurizio Carlini, Massimo Cecchini, Francesco Santoro, Antonio Pantaleo.
March 27, 2023 (v1)
Subject: Environment
Keywords: anaerobic digestion, compost, externalities, global warming potential, life cycle assessment.
Italian power generation through anaerobic digestion (AD) has grown significantly between 2009 and 2016, becoming an important renewable energy resource for the country, also thanks to the generous incentives for produced electricity available in the last years. This work focuses on the economic and environmental issues of AD technology and proposes a techno-economic analysis of investment profitability without government support. In particular, the analysis focuses on an AD power plant fed by zootechnical wastewater and agro-industrial residues coupled to a cogeneration (CHP) system and a digestate-composting plant that produces soil fertilizers. We aim to determine the economic profitability of such AD power plants fed by inner-farm biomass wastes, exploiting digestate as fertilizer, using the cogenerated heat and taking into account the externalities (environmental benefits). Environmental analysis was carried out via a life cycle analysis (LCA), and encompassing the production of b... [more]
Survey of Sustainable Regeneration of Historic and Cultural Cores of Cities
Mehrdad Chahardowli, Hassan Sajadzadeh, Farshid Aram, Amir Mosavi.
March 27, 2023 (v1)
Subject: Environment
Keywords: historic core of cities, literature review, PRISMA, smart cities, state-of-the-art, suburbanized core cities, survey, sustainable architecture, sustainable cities, sustainable development, sustainable development goals (SDGs), sustainable regeneration, sustainable urban development, urban cores.
The united nations educational, scientific and cultural organization (UNESCO) considers the historic urban landscapes as the world heritages. Managing historic city centers and maintaining historic cores are the emerging challenges for sustainable urban planning. Today, the historic cores form an important part of the economic, social, environmental, and physical assets and capacities of contemporary cities, and play a strategic role in their development. One of the most important approaches to the development of central textures, especially in historical and cultural cities, is the sustainable urban regeneration approach, which encompasses all aspects of sustainability, such as the economic, social, cultural and environmental aspects. To maintain sustainability and regeneration of historic cores of cities, it is necessary to provide insight into the underlying characteristics of the local urbanization. Furthermore, the fundamental assets are to be investigated as indicators of sustain... [more]
Life Cycle Assessment and Energy Balance of a Novel Polyhydroxyalkanoates Production Process with Mixed Microbial Cultures Fed on Pyrolytic Products of Wastewater Treatment Sludge
Luciano Vogli, Stefano Macrelli, Diego Marazza, Paola Galletti, Cristian Torri, Chiara Samorì, Serena Righi.
March 27, 2023 (v1)
Subject: Environment
Keywords: bio-based polymers, biodegradable plastics, energy metrics, LCA, PHAs, pyrolysis, volatile fatty acids.
A “cradle-to-grave” life cycle assessment is performed to identify the environmental issues of polyhydroxyalkanoates (PHAs) produced through a hybrid thermochemical-biological process using anaerobically digested sewage sludge (ADSS) as feedstock. The assessment includes a measure of the energy performance of the process. The system boundary includes: (i) Sludge pyrolysis followed by volatile fatty acids (VFAs) production; (ii) PHAs-enriched biomass production using a mixed microbial culture (MMC); (iii) PHAs extraction with dimethyl carbonate; and iv) PHAs end-of-life. Three scenarios differing in the use of the syngas produced by both pyrolysis and biochar gasification, and two more scenarios differing only in the external energy sources were evaluated. Results show a trade-off between environmental impacts at global scale, such as climate change and resources depletion, and those having an effect at the local/regional scale, such as acidification, eutrophication, and toxicity. Proce... [more]
Solid-State Fermentation (SSF) versus Submerged Fermentation (SmF) for the Recovery of Cellulases from Coffee Husks: A Life Cycle Assessment (LCA) Based Comparison
Eva Catalán, Antoni Sánchez.
March 27, 2023 (v1)
Subject: Environment
Keywords: cellulase, coffee husk, life cycle assessment (LCA), solid-state fermentation (SSF), submerged fermentation (SmF), waste.
This article studies the environmental impacts of cellulase production by using a comparative attributional life cycle assessment (LCA) of two different scenarios of production. The first one is the commonly used submerged fermentation (SmF) using a pure substrate (cellulose powder) and a specific microorganism (Trichoderma reesei). The second scenario considers a novel system to produce enzymes and simultaneously treat a waste using the solid-state fermentation (SSF) process of coffee husk (CH) used as substrate. Experimental data were used in this scenario. The complete production process was studied for these two technologies including the fermentation phase and the complete downstream of cellulase. Life cycle inventory (LCI) data were collected from the database EcoInvent v3 (SimaPro 8.5) modified by data from literature and pilot scale experiments. The environmental impacts of both production systems revealed that those of SmF were higher than those of SSF. A sensitivity analysis... [more]
Exergetic Life Cycle Assessment: A Review
Martin N. Nwodo, Chimay J. Anumba.
March 27, 2023 (v1)
Subject: Environment
Exergy is important and relevant in many areas of study such as Life Cycle Assessment (LCA), sustainability, energy systems, and the built environment. With the growing interest in the study of LCA due to the awareness of global environmental impacts, studies have been conducted on exergetic life cycle assessment for resource accounting. The aim of this paper is to review existing studies on exergetic life cycle assessment to investigate the state-of-the-art and identify the benefits and opportunity for improvement. The methodology used entailed an in-depth literature review, which involved an analysis of journal articles collected through a search of databases such as Web of Science Core Collection, Scopus, and Google Scholar. The selected articles were reviewed and analyzed, and the findings are presented in this paper. The following key conclusions were reached: (a) exergy-based methods provide an improved measure of sustainability, (b) there is an opportunity for a more comprehensi... [more]
Characteristics of Miscanthus Fuel by Wet Torrefaction on Fuel Upgrading and Gas Emission Behavior
Jae-Hyun Park, Young-Chan Choi, Young-Joo Lee, Hyung-Taek Kim.
March 27, 2023 (v1)
Subject: Environment
Keywords: Biomass, combustion, miscanthus, upgrading fuel, wet torrefaction.
Biomass is a solid fuel that can be used instead of coal to address the issue of greenhouse gases. Currently, biomass is used directly in combustion or via co-combustion in coal-fired power plants. However, its use is limited due to calorific value and ash problems. In this study, wet torrefaction (WT) was carried out at various temperatures (160 °C, 180 °C, and 200 °C) and the properties of the product were evaluated. In comparison to dry torrefaction, the ash contained in biomass was extracted by an acidic solution (i.e., acetic acid) from the overreaction of the biomass. From examining the ash content of the treated WT, it was confirmed that K2O of basic ash was mainly extracted. In particular, in the case of K2O, since the main cause of combustion problems are issues such as fouling and slagging, the removed WT can be stably combusted in the boiler. Finally, the combustion and emission behaviors were evaluated by TGA-DTG and TGA-FTIR. As the fuel-N was decreased in the WT proess, t... [more]
Showing records 1228 to 1252 of 3421. [First] Page: 1 47 48 49 50 51 52 53 54 55 Last
(0.18 seconds) 0 + 0
[Show All Subjects]