Уточнить поиск
Результаты 1-10 из 35
Current air quality plans in Europe designed to support air quality management policies
2015
Miranda, Ana | Silveira, Carlos | Ferreira, Joana | Monteiro, Alexandra | Lopes, Diogo | Relvas, Helder | Borrego, C. | Roebeling, Peter
The intensification of the human activity in urban areas as a result of the increasing population has contributed to the air pollution worsening in cities. To reverse this trend, the European Commission established a legal framework to improve the air quality. Thereby the Member States need to develop air quality plans (AQP) for zones and agglomerations where air quality limit values are exceeded, in order to implement pollution control strategies and meet the legal requirements. Understanding the reasons for the levels of air quality non–compliance as well as evaluating available and commonly used tools to predict the air quality and their effects, is crucial for the decision–making process on air quality management policies. Based on a compilation of regional and local AQP, a review of assessment capabilities and used modeling tools to evaluate the effects of emission abatement measures on the air quality and health was performed. In most cases, models are applied to estimate emissions and to assess the resulting air quality from both reference and emission abatement scenarios. Air quality’s impacts on the health and environment are rarely quantified. Regarding the air quality assessment, beyond the modeling, monitored data for validation of simulations are also used. Some studies, however, do not include the use of air quality models, considering the monitoring network as spatially representative of the study domain (e.g. Lisbon Region, Riga, Malta). In order to overcome methodological limitations for quantifying the impacts of emission abatement measures, economic evaluation techniques or even Integrated Assessment Methodologies (IAM) have been developed. IAM, already applied in some AQP or case studies, namely for Antwerp and London, are used for assessing how reductions in emissions contribute to improve air quality, reduce exposure and protect human health.
Показать больше [+] Меньше [-]Enhanced Solar Photovoltaic Power Production Approach for Electric Vehicle Charging Station: Economic and Environmental Aspects
2024
J. Techo, S. Techo, A. Palamanit, E. Saniso, A. A. Chand and P. Prasannaa
In recent years, Electric Vehicles (EVs) are contributing a major share in Thailand and benefit the environment. Most of the EV charging stations are sourced from solar energy as it becomes a carbon-free source of energy production. Secondly, Thailand is rich in solar irradiance, and higher irradiance leads to higher power production. On the other hand, in tropical conditions, solar Photovoltaic (PV) module temperature increases following the solar irradiance due to high ambient temperature, resulting negative impact on the efficiency and lifespan of photovoltaic (PV) modules. Further, to increase PV power production, in this study, different rates of cooling strategies are proposed. The study found that reducing the temperature by 5% to 25% resulted in increased average power outputs of 5947.94W, 6021.43W, 6094.92W, 6168.41W, and 6241W, respectively. Notably, 25% of the cooling rate achieved higher production. However, it is lower than the nominal power production. Following that, economic analysis and environmental impacts are analyzed for Thailand’s EV charging station using a different cooling rate of PV module. Overall, it is concluded that, depending on the economic viability of the EV charging station, cooling technology can be applied, and it will benefit the EV charging station both economically and environmentally. To further enhance the solar PV power production approach for EV charging stations in Thailand, it is imperative to prioritize future endeavors towards optimizing cooling technology, integrating energy storage, and implementing supportive policies.
Показать больше [+] Меньше [-]Experimental investigation of 4E performance studies of a vertical bifacial solar module during summer and winter
2022
Muthu, Vimala | Ramadas, Geetha
The proposed research work presents the performance analysis of the vertically mounted bifacial module (VBFM) with and without tracking during the summer and winter seasons. Also, various parameters like energy efficiency, electrical efficiency, electrical exergy, thermal exergy, exergy efficiency, environmental analysis, economic analysis, exergoeconomic analysis, enviroeconomic analysis, and exergoenviroeconomic analysis of the VBFM were studied and presented. The comparative analysis was carried out between two bifacial solar modules installed in two different orientations (east–west and south-north). The experiments were conducted in the real climatic condition of Minjur, Tamil Nadu, India. Under the summer and winter climatic conditions, when the lifetime period of 10, 15, and 20 years are considered higher energy production factor and higher life cycle conversion efficiency was obtained from the vertically mounted bifacial module—east–west (VBFM-EW) with tracking during summer and vertically mounted bifacial module—north–south (VBFM-SN) module without tracking during the winter season. Exergetic cost was calculated by considering 15, 20, 25, and 30 years of the system with 2%, 5%, and 10% interest rates. The maximum exergetic cost was obtained from 30 years of the system under a 2% interest rate. The enviroeconomic and exergoenviroeconomic analysis provides the carbon credits earned from the E-W module was a maximum of Rs 11,036.18 during the summer season and Rs 12,413.48 from the VBFM-SN module during the winter season, considering the life of the system as 15 years.
Показать больше [+] Меньше [-]An experimental investigation of a water desalination unit using different microparticle-coated absorber plate: yield, thermal, economic, and environmental assessments
2021
Thakur, Amrit Kumar | Sathyamurthy, Ravishankar | Sharshir, Swellam Wafa | Kabeel, Abd Elnaby | Manokar, Athikesavan Muthu | Zhao, Wensheng
This study aims to augment the performance of a solar desalination unit. To experimental examine this idea, a modified solar still with three different microparticles doped in black paint-coated absorber were designed, fabricated, and tested in Jaipur, India. Three different microparticles such as copper, aluminum, and tin with particle size of 50–80 μm with weight concentration of 10% were doped in black paint and then coated on the absorber of solar still. The coated absorber of solar still were compared with the conventional solar still without any microparticle coating to obtain the effect of different coating materials on the water productivity, thermal performance, economic, and environment-economics analysis of solar still. The result showed that under the water depth of 1 cm, coating of copper, aluminum, and tin on absorber augmented the full-day water yield by 33.13, 22.18, and 11.53%, compared to conventional solar still without any coating. In addition, full-day energy and exergy efficiency of solar still with copper-coated absorber exhibited maximum values compared to all other solar stills, owing to the higher thermal conductivity and excellent solar-thermal conversion behaviors of copper. The cost of water per liter estimated through economic analysis was found to be US $ 0.0074 for conventional solar still, which was significantly reduced to US $ 0.0066 in the case of solar still with copper-coated absorber along with the payback time of 2.7 months. The environment-economic assessment estimated that solar still with copper-coated absorber plate has reduced the 13.19 tons of CO₂ emission. It is concluded that augmented heat transfer rate from water basin to inner glass surface through utilization of microparticle coating would pave a pathway to develop energy-efficient low-cost solar-based desalination system.
Показать больше [+] Меньше [-]Productivity enhancement of single-slope solar still with novel bottom finned absorber basin inserted in phase change material (PCM): techno-economic and enviro-economic analysis
2021
Suraparaju, Subbarama Kousik | Natarajan, Sendhil Kumar
Solar still is one of the economic and eminent ways of desalinating the available sea/brackish water into potable water. However, the distillate output from the solar still is moderate and various researches are being conducted to improve the productivity of solar still. In this research, a novel bottom finned (solid and hollow) absorber basin is designed and developed to enhance the heat transfer between absorber and phase change material (PCM) which further improves the freshwater productivity from the solar still. The results of the investigation are compared with the conventional solar still. The three single-slope solar stills considered developed for evaluating the effect of modification on the freshwater productivity are (i) conventional solar still (CSS), (ii) solar still with hollow finned absorber inserted in energy storage (SSHFES), and (c) solar still with solid finned absorber inserted in energy storage (SSSFES). The investigation results reported that the SSHFES has greater productivity when compared with the SSSFES and CSS. The freshwater productivity from the SSHFES is 4085 mL/m² day, whereas the freshwater productivity from SSSFES and CSS is 3485 mL/m² day and 2885 mL/m² day, respectively. The efficiency of SSHFES and SSSFES is increased by 41.67% and 20.81% relative to the CSS. It is observed from economic analysis that the cost per liter (CPL) freshwater produced by SSHFES, SSSFES and CSS is about ₹ 2.3 ($ 0.032), ₹ 2.5 ($ 0.034), and ₹2.6 ($ 0.036), respectively. The payback periods of SSHFES, SSSFES, and CSS is 6.3 months, 6.8 months, and 7.1 months, respectively. Also, the enviroeconomic analysis conferred that the carbon credit gained from the SSHFES is $189.28 whereas SSSFES and CSS gained only $158.2 and $132.02. Based on the current study, it is observed that the solar still with hollow finned absorber inserted in energy storage (SSHFES) is effective when compared to others and it is viable for potable water production at cheaper costs.
Показать больше [+] Меньше [-]Freeze–thaw combined with activated carbon improves electrochemical dewaterability of sludge: analysis of sludge floc structure and dewatering mechanism
2022
Hui, Kai | Song, Lei | Yin, Zhenzhou | Song, Hongwei | Wang, Zehao | Gao, Wenjian | Xuan, Lili
Freeze–thaw (F/T) and electrochemistry both are environment-friendly and efficient sludge treatment technologies. In this study, the sludge samples were frozen at − 15 °C, and 20% g/gTss activated carbon (AC) was added to the dissolved sludge. Finally, the uniformly mixed sludge was treated at a voltage of 15 V for 25 min. During the experiment, the effect of F/T on the floc structure was analyzed by a laser particle analyzer and scanning electron microscope. F/T treatment improved the dewatering performance of the sludge and promoted the aggregation of sludge flocs into larger particles either. At the same time, the median diameter (D50) increased from 45.27 to 128.94 μm. AC was added to the thawed sludge solution before electrochemical treatment (EP). The conductivity of AC enhanced the effect of EP, thereby cracking the sludge flocs. Therefore, the three-dimensional excitation–emission matrix (3D-EEM) intensity of tightly bound extracellular polymeric substances (TB-EPS) decreased significantly. The protein in TB-EPS decreased from 54 to 33%, and the D50 was also reduced to 105.3 μm. The final specific resistance of filtration and water content were reduced by 96.39% and 32.17%, respectively. The dehydrated cake elemental analysis showed that increased AC improved the sludge cake’s combustion efficiency significantly. Moreover, the preliminary economic analysis indicated that the cost of this research was low, which implied the potential application value of combined treatment.
Показать больше [+] Меньше [-]Economic Analysis and Development of the Nile Tilapia Cultivated in the Nursery Using Reject Brine as Water Support
2022
Souza, Ana Cláudia Medeiros | Dias, Nildo da Silva | Arruda, Maria Valdiglezia de Mesquita | Fernandes, Cleyton dos Santos | Alves, Halysson Rubens | Nobre, Gerson Talles Nogueira | Peixoto, Maria Luiza Lima Ferreira | de Sousa Neto, Osvaldo Nogueira | Silva, Márcia Regina Farias da | da Silva, Francisco Valfísio | Sá, Francisco Vanies da Silva
Reverse osmosis desalination is a solution for water supply in rural communities in the semi-arid region. However, the disposal of waste generated in the process has been a challenge. Thus, a study was conducted to evaluate the economic viability and development of Nile tilapia (Oreochromis niloticus) cultivated in nurseries using water support, the rejected brine from the brackish water treatment plant. The study was conducted in the rural community of Serra Mossoró, Mossoró, RN, Brazil, benefited by the “Água Doce” program with a desalination plant. For this, two nurseries were built for fish farming and a tank to receive fish effluent. Each nursery was populated with 700 male Nile tilapia fingerlings. To determine fish growth, biometric analyses of head length, partial length, total length, height, width, and average weight were performed every 30 days after stocking. The economic analysis consisted of identifying the financial inflows and outflows. The results showed that all biometric parameters increased linearly with the time of cultivation, indicating that tilapia development and production using reject brine were satisfactory, making this waste feasible in fish farming. Economically, the project proved to be unfeasible in the short term, requiring a longer execution time of the generated cash flows to cover the initial investment. Despite this, the project generated positive social and environmental impacts. The raising of tilapia is a viable alternative for draining saline waste and ensuring food and nutritional security for family farming.
Показать больше [+] Меньше [-]Sustainable Treatment of Antibiotic Wastewater Using Combined Process of Microelectrolysis and Struvite Crystallization
2015
Zhang, Jishi | Chen, Shujun | Wang, Xikui
The aim of this study was to investigate the synergistic effects of the process of iron-carbon microelectrolysis (ICME) followed by struvite (MAP) crystallization on treating antibiotic wastewater. Characteristics of ICME effluent depended mainly on the iron to carbon mass ratio (Fe/C). The optimum reaction conditions of Fe/C ratio of 2:1 and reaction time of 90 min were observed. The ICME effluent was further treated by MAP crystallization using Na₂HPO₄·12H₂O and MgCl₂·6H₂O as precipitation agents. The results showed that, the Mg²⁺/NH₄ ⁺-N/PO₄ ³⁻-P molar ratio of 1:1:1 and pH 8.5, were suitable for the crystallization process, which could obtain high-quality MAP containing 5.18 % N,10.23 % Mg, and 13.83 % P. Optimal total removal rate of COD and NH₄ ⁺-N removal rate achieved 84.6 and 89.9 %, respectively. The economic evaluation of NH₄ ⁺-N recovery by the synergistic process was also conducted, indicating that the synergistic process had the potential to benefit COD emission reduction and nitrogen recovery. Graphical Abstract The aim of this study was to investigate the effects of treating antibiotic wastewater using iron and carbon combined process of microelectrolysis and struvite (MAP) crystallization. The MAP was of high purity and good crystal morphology, which could be used as a slow-release fertilizer.
Показать больше [+] Меньше [-]Effects of Water Network Synthesis on the Air Pollutant Emissions and Energy Consumption of a Whole Economy
2009
Lim, Seong-Rin
Environmental and energy performances of a water network system (WNS) utilizing water reuse are compared to those of a conventional water system (CWS) supplying only freshwater from the perspective of an entire economy and life cycle. Environmental input-output analysis (EIOA) is used to evaluate their air pollutant emissions and energy consumptions. The global warming potential and the emissions of carbon monoxide and of volatile organic compounds from the WNS are less than those from the CWS because of the decrease in the consumption of industrial water, while the emissions of sulfur dioxide and of nitrogen oxides and energy consumption from the WNS are greater because of the increase in electricity consumption for pumping. For perfectly environmentally-friendly water reuse, electricity consumption should be constrained or optimized in water network synthesis, and primary energy mix for electricity generation should be shifted towards renewable energy.
Показать больше [+] Меньше [-]Biomass District Energy Trigeneration Systems: Emissions Reduction and Financial Impact
2009
Rentizelas, A | Tolis, A | Tatsiopoulos, I
Biomass cogeneration is widely used for district heating applications in central and northern Europe. Biomass trigeneration on the other hand, constitutes an innovative renewable energy application. In this work, an approved United Nations Framework Convention on Climate Change baseline methodology has been extended to allow the examination of biomass trigeneration applications. The methodology is applied to a case study in Greece to investigate various environmental and financial aspects of this type of applications. The results suggest that trigeneration may lead to significant emissions reduction compared to using fossil fuels or even biomass cogeneration and electricity generation. The emissions reduction achieved may be materialized into a considerable revenue stream for the project, if traded through a trading mechanism such as the European Union Greenhouse Gas Emission Trading Scheme. A sensitivity analysis has been performed to compensate for the high volatility of the emission allowances' value and the immaturity of the EU Trading Scheme, which prevent a reliable estimation of the related revenue. The work concludes that emission allowances trading may develop into one of the major revenue streams of biomass trigeneration projects, significantly increasing their financial yield and attractiveness. The impact on the yield is significant even for low future values of emission allowances and could become the main income revenue source of such projects, if emission allowances increase their value substantially. The application of trigeneration for district energy proves to lead to increased environmental and financial benefits compared to the cogeneration or electricity generation cases.
Показать больше [+] Меньше [-]