Energy
I. Pishkar; S. M. Beigi
Abstract
With sensitive and important systems in hospitals requiring an uninterrupted power supply, finding solutions for power outages is becoming increasingly crucial. Iran's favorable potential for renewable energy makes wind and solar energy viable options to support hospital electricity needs and contribute ...
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With sensitive and important systems in hospitals requiring an uninterrupted power supply, finding solutions for power outages is becoming increasingly crucial. Iran's favorable potential for renewable energy makes wind and solar energy viable options to support hospital electricity needs and contribute to sustainable development goals. The present work investigates, for the first time, the electricity supply of a part of the Parsian Hospital in Shahrekord using HOMER software. The use of real electricity exchange data with the national grid and the new generation of tree-shaped wind turbines are unique advantages. Results show that an optimal renewable energy-based system consisting of two 1-kW solar cells and a 1-kW electric converter costs $0.111 per kWh and solar cells generate 3% or 2999 kWh/year. The optimal scenario produces 55193 kg of CO2 annually due to national grid electricity use, highlighting the importance of renewable energy adoption in hospitals.
Environment
M. Bisong Obi; A. Abubakar; S. Yunusa; F. Mohammed
Abstract
This work investigated the optimization of process parameters for catalytic pyrolysis of waste tyre using reactivated spent Fluid catalytic cracking (FCC) catalyst. The waste tyre pyrolysis used design expert software as the optimization tool for this study. A 3-factor level CCD with 20 experimental ...
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This work investigated the optimization of process parameters for catalytic pyrolysis of waste tyre using reactivated spent Fluid catalytic cracking (FCC) catalyst. The waste tyre pyrolysis used design expert software as the optimization tool for this study. A 3-factor level CCD with 20 experimental runs was used with temperature, time and catalyst as the input parameters while oil yield, density and viscosity were the output variables. Thereafter, an experimental validation of the optimized parameters, which were not among the original experimental runs, was carried out. Pyrolysis was also carried out at the optimized conditions with un-reactivated catalyst and without catalyst to ascertain the contributions of the catalyst and its reactivation. Based on the optimum parameters, 48.5 wt. % oil (0.79 g/ml and 2.05 cSt) was produced with the reactivated catalyst, 43.4 wt. % (0.86 g/ml and 3.52 cSt) was produced with spent catalyst, and 51 wt. % oil (0.95 g/ml and 4.24 cSt) was produced without catalyst. The oil yield without catalyst was higher than with reactivated catalyst (R-CAT); but it however had the lowest fuel qualities while oil produced with catalyst in turn had higher quantity and quality compared to oil produced with catalyst. Therefore, the incorporation of density and viscosity of the oil in the optimization of the catalytic pyrolysis of waste tyre enhanced the improvement of yield and quality of the oil produced.
Chemical Engineering
M. Ibrahim Abduljabbar; H. Ghafouri Taleghani; I. Esmaili Paeen Afrakoti
Abstract
In this research, gas sweetening process of the Iraq Majnoon refinery plant and its optimization scenarios were investigated using ASPEN HYSYS 8.4 and genetic algorithm optimization. First, values of optimization parameters such as the values of the population, generations and crossover for single and ...
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In this research, gas sweetening process of the Iraq Majnoon refinery plant and its optimization scenarios were investigated using ASPEN HYSYS 8.4 and genetic algorithm optimization. First, values of optimization parameters such as the values of the population, generations and crossover for single and multi-objective optimizations were obtained. The effect of temperature and molar flow of feed gas and make-up water on concentration of CO2 and H2S in the sweet gas were studied. The result showed that with increasing the temperature and molar flow of feed gas, the concentration of CO2 and H2S in the sweet gas was increased. The single and multi-objectives’ optimizations of process were carried out with minimizing the concentration of CO2 and H2S, minimizing the consumed energy of stripper and overall consumed energy of plant including energy of stripper and cooler. It was observed that for optimization of concentration of CO2 and H2S, mole fraction of CO2 and H2S decreased to minimum amounts of 5.52 e-4 and 6.84 e-9 between optimization data sets. Also, it was found that with increasing the number of objective functions of the optimization, the ability of the algorithm to reduce the amount of the objective functions decreases, because genetic algorithm should consider more constraints with increasing the number of objective functions. The novelty of this research was a comprehensive study of gas sweetening process optimization with single to four objectives.
Environment
A. Shola Rinde; A. Mustapha; A. Francis Olatunbosun
Abstract
Harmattan dust has been identified as a discrete mass of solid earth crust hanging in the air for an extended period of time. It has been noted that less studies have been conducted in Nigeria to determine the functional groups contained in harmattan dust. The goal of this study was to figure out what ...
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Harmattan dust has been identified as a discrete mass of solid earth crust hanging in the air for an extended period of time. It has been noted that less studies have been conducted in Nigeria to determine the functional groups contained in harmattan dust. The goal of this study was to figure out what functional groups and chemicals that were present in the dust. Usmanu Danfodiyo University, Sokoto (12°N, 13.8°E), Kebbi State University of Science and Technology, Aliero (12.3070°N, 4.4955°E), Federal University of Agriculture, Zuru (11.4058°N, 5.2400°E), and Waziri Umaru Federal Polytechnic, Birnin Kebbi (12.4601°N, 4.4955°E), were the selected stations used in this study. The suspended Harmattan dust samples were obtained in glass petri plates using a direct deposition approach. Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatograph-Mass Spectrometry (GC-MS) were used to examine the samples collected. The results show that eleven functional groups were present in the samples, including =CH-H, -CH3, N-H, C=C, =C-H, C-H, O-H, C-N, C=O, C-O-C, and -CH3. According to GC-MS, the component (2-methoxy ethyl) had the greatest quality value (Q-Value) of 83, area percentage corresponding to time rating (RT) of 13.647, and CAS 018173-63-2 in the dust samples. It is therefore recommended that the Federal Republic of Nigeria's government increase funding for the research centers so that researchers can study all cities in the country and better observe the functional group metals present in the harmattan dust.
Energy
M. Bagheri; I. Mirzaee; M. Khalilian; V. Mousapour
Abstract
The present study simulates Invelox in a three-dimensional and stable way. The flow regime is turbulent flow and an unorganized grid with 350000 cells was utilized. This work has studied the modeling of invelox with conventional dimensions and four different sizes in the form of four modes for use in ...
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The present study simulates Invelox in a three-dimensional and stable way. The flow regime is turbulent flow and an unorganized grid with 350000 cells was utilized. This work has studied the modeling of invelox with conventional dimensions and four different sizes in the form of four modes for use in a residential building. The numerical data with an error of less than 6% are in good agreement with the available experimental and analytical data. The results show that considering the average velocity of mode 2 with a velocity of 6.54 m/s and a 5% difference from the other two modes, it can be operated in a residential building. It is worth noting that in this investigation, in addition, the effect of dust on the turbine performance was evaluated. The results represent that the oscillation frequency of the blades increases with the increase of the rotational speed. In the case of not considering dust particles on blades, this amount increases by 25%, while considering dust particles with an amount of 0.1%, it increases up to 300%, and this can cause irreparable damage to the turbine as well as the power generation system.
Energy
A. Bozorgi; M. J. Zarei
Abstract
Noise pollution is one of the biggest problems of wind turbines, especially when these turbines are located near residential areas. In this article, the effect of blade thickness is numerically investigated on the noise pollution of an H-type Darrieus wind turbine. The flow is first simulated using the ...
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Noise pollution is one of the biggest problems of wind turbines, especially when these turbines are located near residential areas. In this article, the effect of blade thickness is numerically investigated on the noise pollution of an H-type Darrieus wind turbine. The flow is first simulated using the unsteady Reynolds averaged Navier-Stokes equations and the SST-kω model at the tip speed ratio of 2.64. Then, the noise is calculated using Ffowcs Williams-Hawkings equations. Blade thickness is changed using NACA airfoils from NACA 0008 up to NACA 0024. It is concluded that noise calculation at only one point, known as a routine method in noise investigation of wind turbines, is insufficient to investigate the noise of this turbine. Here, maximum noise in directivity is defined as the criterion of noise pollution. The results show that changing the blade profile of the benchmark turbine from NACA 0021 to NACA 0015 increases the power coefficient from 0.318 to 0.371 and reduces the maximum noise from 95.67 dB (76.35 dB) to 90.19 dB (71.01 dB) at R = 2 m (8m). For NACA 0018, the power coefficient is 0.353, and the maximum noise is 89.78 dB (70.47 dB) at R = 2 m (8m). Overall, the highest output power is for NACA 0015, and the lowest noise pollution is for NACA 0018.
Energy
A. Kamyab; M. Mahmoudi Zarandi; M. Nikpour
Abstract
Yazd is located in a hot-dry region with harsh weather conditions. Houses with an iwan were suitable for establishing comfort conditions in the past. An evaluation of the visual comfort conditions in residential courtyard buildings in Yazd city was carried out by investigating the effects of the depth ...
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Yazd is located in a hot-dry region with harsh weather conditions. Houses with an iwan were suitable for establishing comfort conditions in the past. An evaluation of the visual comfort conditions in residential courtyard buildings in Yazd city was carried out by investigating the effects of the depth of the iwan and the ratio of the adjacent rooms' openings. Research is currently being conducted on an optimal model of the iwan in an effort to facilitate sustainable development and increase the use of such a model in contemporary housing. The effect of the parameters was investigated by simulating models containing different proportions of the iwan and sizes of the window in the Design Builder software. The results indicate that the proportion of the iwan and Window Wall Ratio of the adjacent room's window significantly affects the daylight that penetrates into the rooms. For the purposes of this study, climate-based daylight metrics (CBDMs), such as Useful Daylight Illuminances (UDI) with thresholds of 100–3000 lux and Spatial Daylight Autonomy (sDA) over 300 lux. In models with an iwan depth of 1.5 and above, windows from 20% to 60% WWR have the ability to bring a suitable amount of light into the room. This means that by using the iwan, wider windows can be designed without having glare and adding extra thermal load to the building. Results obtained from this research will provide new insight into the concepts of iwan. Furthermore, findings of this research help architect to design spaces with the utilization of daylight.
Chemical Engineering
M. Mahmoudi; I. Mirzaee; M. Khalilian
Abstract
The exploitation of nanofluids is the most noteworthy way to make better the rate of heat transfer in solar collectors. Moreover, recently utilizing thermoelectric generators are widely studied to direct the conversion of heat into electricity. The objective of the present study is to deal with a novel ...
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The exploitation of nanofluids is the most noteworthy way to make better the rate of heat transfer in solar collectors. Moreover, recently utilizing thermoelectric generators are widely studied to direct the conversion of heat into electricity. The objective of the present study is to deal with a novel multigeneration system that includes a nanofluid-based parabolic trough collector integrated with a quadruple effect absorption refrigeration cycle (cooling), a thermoelectric generator (power), a PEM electrolyzer (hydrogen), vapor generator and domestic water heater. A parametric study is accomplished to consider the effect of significant parameters such as the volume concentration of nanoparticles, solar radiation, absorption system’s generator load, strong solution concentration, and TEG’s figure of merit on the overall system performance, hydrogen production rate, cooling load, COP and useful energy obtained by the collector. It is observed that the power generated by the system is 18.78 kW and the collector energy and exergy efficiency are 82.21% and 80.48%, respectively. Furthermore, the results showed that the highest exergy destruction rate occurs in the solar system at the rate of 4461 kW. The energy and exergy COPs of the absorption chiller are discovered to be 1.527 and 0.936, respectively. By increasing the concentration of nanoparticles and the amount of solar radiation, the amount of collector useful energy increases while the hydrogen production rate and the generated power in the TEG decreased. The cooling capacity and COPs of the absorption system increased with an increase in VHTG load and decreased with an increase in concentration of the strong solution.
Environment
M. J. Islam
Abstract
Dhaka, the capital of Bangladesh, is encircled by six rivers like a garland. Dhaka's growing population, urbanization, and modernization are causing problems with wastewater discharges and water pollution in the river's water body. These rivers receive wastewater from numerous sources, which are discharged ...
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Dhaka, the capital of Bangladesh, is encircled by six rivers like a garland. Dhaka's growing population, urbanization, and modernization are causing problems with wastewater discharges and water pollution in the river's water body. These rivers receive wastewater from numerous sources, which are discharged as industrial effluents, municipal sewage, household wastes, clinical wastes, and oils. The water of these rivers is being polluted to an increasing degree. This study investigated how the surface water in Dhaka's rivers varies throughout the year. The results of various water quality indices, such as DO, BOD, COD, pH, TDS, EC, SS, Turbidity, and alkalinity, were compared with the guidelines set by Bangladesh's Department of Environment (DoE) and the World Health Organization (WHO). Sample collection was done in two seasons in a year, dry season and wet season. In this study, researchers also aim to determine the effect of this wastewater on the river water and thus provide a report on the state of a numerical rating for determining the rivers' water quality.
Water Resources Engineering
M. Nadi; A. Yousefi Kebriya
Abstract
Accurate spatial estimation of temperature is very important in meteorological research. This study investigated the efficiency of temperature products of the Tropical Rainfall Measuring Mission (TRMM) satellite in estimating temperature in Mazandaran Province, and its accuracy were compared with inverse ...
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Accurate spatial estimation of temperature is very important in meteorological research. This study investigated the efficiency of temperature products of the Tropical Rainfall Measuring Mission (TRMM) satellite in estimating temperature in Mazandaran Province, and its accuracy were compared with inverse distance weighting and Co-Kriging interpolation methods. Finally, a new method was proposed to improve the accuracy of temperature estimation by combining the TRMM temperature products and terrains. Data recorded at 25 meteorological stations and 26 monthly and annual TRMM satellite images in 2012 and 2013 were used. The results showed a significant correlation between temperature data and satellite products, latitude, and altitude in significance level of 95%. Analyzing error indices showed that TRMM products have underestimation error that this bias error contributed to about 60% of error in these satellite images. Despite the larger error of TRMM products than interpolation methods, the regression analysis results demonstrated the superiority of satellite temperature products over interpolation methods. Furthermore, higher correlation of observed and estimated data showing that satellite products give a better understanding of cold and hot points of the study area despite its underestimation error. Combining satellite temperature products with influential covariates of altitude and latitude in the regression equation reduced the temperature estimation error of the TRMM products by 80%. The estimation precision increased over 70% compared to other temperature interpolation methods. Analyzing isotherm maps indicate the higher temperature of eastern coasts than western coasts. Moreover, evaluating different temperature estimation methods showed the higher precision of the methods that involved covariates than other methods.
Energy
I. U. Siloko; E. Enoyoze
Abstract
Wind is a significant weather variable and its study has gained convincing attention recently due to its increasing importance as a source of renewable energy as well as its role in various natural phenomena like erosion, precipitation, and spread of wildfires. This paper investigates wind speed distribution ...
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Wind is a significant weather variable and its study has gained convincing attention recently due to its increasing importance as a source of renewable energy as well as its role in various natural phenomena like erosion, precipitation, and spread of wildfires. This paper investigates wind speed distribution in Delta State, Nigeria using a nonparametric statistical technique for ten consecutive years spanning from 2011 to 2020 across three stations. The nonparametric statistical approach is the kernel density estimation with focus on Gaussian kernel estimator. The results of the investigated period revealed that wind speed in Asaba that is located in Delta North is higher in comparison with the wind speed in Patani which is situated in Southern region of the State while the wind speed is low at Sapele in Delta Central. Therefore, installation of wind power generation system is more profiting in the Northern part because the amount of wind energy generated is determine by the wind speed. Again, the performance of agricultural or industrial activities that depend on wind speed for their proper execution is optimum in 2018 while the least performances were recorded in 2015 and 2016 respectively for the period explored.
