Iranica Journal of Energy & Environment
Volume:16 Issue: 1, Winter 2025

Industrial processes are among human activities that cause production of a large volume of wastewater containing organic pollutants such as phenol and its derivatives. Soil remediation is crucial for enhancing environmental quality for both humans and other living organisms. This study investigate the use of an electro-peroxone system to remove environmental pollutants from soil. In conjunction with ozonation, the study employed electrochemically generated hydrogen peroxide using a carbon electrode, addressing concerns about transportation and storage. Experiments were structured using response surface methodology (RSM) with three variables: ozone dosages ranging from 4 to 8 l/h, initial pollutant concentrations from 20 to 50 mg/kg, and treatment durations between 7 and 14 days. The effectiveness of phenol removal from soil was assessed by applying a consistent voltage of 2 V/cm to the soil samples in all experiments. Results revealed a negative correlation between initial pollutant concentration and ozone consumption and a positive correlation between treatment duration and pollutant removal efficiency. Optimal removal efficiency occurred with a 14-day treatment duration, an 8 l/h ozone dosage, and a 20 mg/kg initial pollutant concentration. The electro-peroxone system's application indicates its potential as a sustainable, eco-friendly, and cost-effective approach to soil remediation for pollution.

In the present paper, the effect of inclination angle on the free convection airflow inside the cavity of compound parabolic collectors and also on the performance of the thermal system is examined. In the analysis, airflow equations for computations of velocity, pressure, and temperature fields and the conduction equation for obtaining the glass cover and absorber tube temperatures are solved by the finite element technique using the COMSOL multi-physics. For this purpose, the well-known κ-ε turbulent model is employed with the Reynolds average Navier Stokes scheme. Theoretical findings reveal that the pattern of air-free convection flow and also the temperature distribution are much affected by the collector inclination angle, such that the symmetric bi-cellular air flow at zero inclined angle changes to two non-symmetric recirculated zones at a large value of the till angle. This phenomenon causes a slight increase in thermal efficiency and leads to a more uniform air temperature distribution inside the collector. Numerical findings are validated by comparison with experimental data published in the literature.

The proliferation of electrical and electronic products in modern lifestyles has led to a significant increase in standby power consumption, posing a challenge for energy conservation efforts. In response, this study explores the potential of user-centric design methodologies in addressing standby power management and energy efficiency. By analyzing human error categories and user interaction behavior, the research aims to identify design gaps and develop strategies for mitigating human errors in standby power usage. Through an exploratory and explanatory approach, data gathered from questionnaires provide insights into users' habits, needs, attitudes, and reflections related to standby power consumption. The findings highlight the potential for user-centric approaches to effectively control standby power in connected appliances, paving the road for future advancements in appliance design that prioritize user behavior and preferences. This study offers a novel perspective on standby power management, emphasizing the importance of human error alleviation and user-centric design in achieving energy efficiency goals.

This study analyzes the thermal efficiency of a new perforated cross-flow solar air heater (SAH) integrated with encapsulated phase change material (PCM) by using an experimnetal approach. Since SAHs represent low thermal efficiencies, this study introduces a novel SAH that uses two methods to address this problem: the perforated absorber with cross-flow configuration and encapsulated latent heat storage (PCM) units. The perforated cross-flow configuration improves the turbulence and, consequently, the heat exchange rate in SAHs and improves instantaneous efficiency. PCM units store thermal energy, prolong the operating period, and increase long-term efficiency. To perform thermal analysis, a perforated SAH with encapsulated PCM units was fabricated and tested outdoors at mair = of 0.012 kg/s and 0.024 kg/s in autumn while ambient and operating parameters were monitored. The experimental data reveal that the outlet temperature reaches the peak value of 38 oC and 32 oC. At mair = 0.012 kg/s and 0.024 kg/s, the temperature readings were 12 oC and 6 oC higher than the ambient temperature respectively. During the day, the charge/discharge process occurs in the encapsulated PCM units, avoids sharp temperature gradients and flattens the outlet and absorber temperatures’ profiles. The fabricated SAH reaches the highest thermal efficiency of nearly 83.7% at mair = 0.024 kg/s, which is a suitable value compared to common SAHs.

The sun is the main source of energy that provides light and heat energy. With the advancements in the power electronic components, grid-tied solar PV Systems are readily available for distributed generation to meet the energy requirements of the customers. The objective of this study and analysis is to predict the potential for solar PV systems and solar thermal energy exploration and the potential for mitigating CO2 emissions and economic benefits. A case study is carried out at Shimoga Milk Union Limited (SHIMUL) Dairy, Machanahalli, Shimoga, Karnataka, India, which handles 75 lakh liters of milk, consumes 2,03,524 units of electricity and 1350 tonnes of steam per month. Analysis has been made on the integration of a 600 kW solar PV system with grid and solar water heaters with the necessary infrastructure for supplying electrical and thermal energy. The study Yields the result that a solar PV System produces 60,000 units per month reduces 29.5% of electrical energy imported from the grid and 50 evacuated tube flat plate collector type solar water heaters of 1000-liter capacity to supply the 50,000 liters of hot water to the boiler at 65˚C reduces input of fuel by 23%, reduces the annual reduction of CO2 emission by 1626 tonnes. Return on Investment for solar PV Systems and solar thermal systems is 4.25 years and 2.7 years, respectively. The analysis extended for each of the various fuels typically used in boilers to produce steam. The procedure developed for estimating the potential for economic and environmental benefits using renewable energy sources for the dairy industry could be extended to any of the industrial sectors that need electrical and thermal energy.

The dissipation of heat generated in electronic and industrial chips is essential for the safe operation of these components. For this purpose, one of the best choices is a microchannel heat sink, which offers a lower pressure drop compared to other channels while maintaining a high heat transfer rate. In this study, a fractal microchannel heat sink, introduced in recent years, has been numerically investigated. To enhance the performance of the microchannel, two types of fins have been added to the microchannel walls, resulting in the creation of two new geometries. In the first new geometry, fins are placed at the bottom of the microchannel, while in the second one, fins are placed on the sidewalls of the microchannel. It is worth mentioning that the volume of fins used is consistent across both geometries. Thermal and hydraulic parameters have been examined, revealing that both new geometries, the Nusselt number increased, with the highest value of 28%. observed in the microchannel with fins on the sidewalls. Additionally, both geometries the pumping power increased by 120% with the microchannel fins at the bottom. Finally, by evaluating the performance coefficient, it was determined that the microchannel with fins on the sidewalls increased the overall performance by 3 to 6% across different flow rates, whereas the microchannel with fins at the bottom reduced the system's performance by 7%. Therefore, for efficient dissipation of the generated heat, it is preferable to use a microchannel heat sink with fins on the sidewalls.

Mazandaran province, due to its strategic geographical location and high influx of tourists during holidays, coupled with the presence of power plants and industrial complexes, is facing pollution challenges. This research, conducted in 2022, focuses on monitoring nitrogen dioxide and ozone pollutants in the province and investigating the role of tourists during certain multi-day holidays. Utilizing Sentinel 5 satellite imagery, including daily images from holidays and non-holidays, the study compensates for the lack of regular pollution data in Mazandaran's monitoring stations by validating the satellite data against Tehran stations. Linear regression equations determine the levels of nitrogen dioxide and ozone pollutants, leading to the creation of an Air Quality Index (AQI) map for Mazandaran province during holidays. The results highlight a strong correlation (0.3-0.7) between satellite and ground data, with ozone pollutants exhibiting a higher correlation. The skew error is consistently zero, and the mean square error varies between 1.9-6.2 ppb for nitrogen dioxide and 1.1-5.1 ppb for ozone. Pollution estimates for different points in Mazandaran province during holidays and non-holidays indicate higher ozone pollution compared to nitrogen dioxide. Ozone pollution is particularly unhealthy and very unhealthy during holiday periods, especially along the coastal areas, while non-holiday days show cleaner and healthier air quality. The pollution index map illustrates higher ozone pollution in coastal cities during holidays compared to other regions, emphasizing the impact of tourists. This research demonstrates the effectiveness of Sentinel 5 satellite in monitoring air pollution and underscores the significant influence of tourists and transportation on Mazandaran province's air quality. The findings advocate for sustainable tourism practices to mitigate the adverse effects on Mazandaran's air quality during holidays.

Using wind energy for hydrogen production in Iran can be important for reasons such as abundant wind resources in Iran, reducing dependence on fossil fuels, ensuring clean energy supply, the potential for hydrogen exports, technology development and job creation. Therefore, this study signifies the first exploration into the potential for generating electricity and producing hydrogen in ten wind-rich cities in Iran. HOMER V.2.81 software was used for simulations, and the wind data used are averaged over a 25-year period. The results show that in Iran, the price range for wind power is $0.515-$0.620 per kWh in the top 10 stations. Bandar Abbas, Parsabad, and Khalkhal had the best economic and environmental performance, respectively. The highest percentage of renewable electricity production is 71% in Bandar Abbas. Finally, the amount of hydrogen produced based on four common electrolyzer types in Iran was investigated. The total annual hydrogen production per ton for SOE, MCE, AE, and PEME electrolysis method at the examined stations is 131.29, 93.43, 40.99, and 30.69, respectively. According to the results, the highest hydrogen production with a value of 16.87 tons per year is related to the Bandar Abbas station and the SOE electrolysis method. The lowest hydrogen production, with a value of 2.36 tons per year, is related to Alvand station and the PEME electrolysis method.

For reading and writing in classrooms therefore a lot of energy is consumed in educational spaces. Limitation of fossil fuels and environmental pollution are two subjects that demonstrate the importance and significance of the present study. Previous studies show that window size and configuration have a significant effect on daylight quality but numbers and the ways of expansion of windows in horizontal and vertical directions of the wall have not been investigated in classrooms in hot and arid regions of Kerman city. The objective of this paper is to evaluate the daylight indicators in different classrooms when different numbers of windows (from 1 window to 5 windows) are applied both horizontal and vertical expansion in each window area from (10%c WWR to 60% WWR). This research has been done through the simulation of different classrooms in Design Builder software under Kerman weather data. Validation of Design Builder has been evaluated through experimental measurement of two actual classrooms and comparing the simulation results and experimental data. The findings of this research demonstrated that using a greater number of windows in classrooms causes a decrease in the amount of daylight penetrating the classrooms.

Considering the unfavorable conditions caused by the wasteful consumption of fossil fuels in order to ensure the comfort of the residents of the building sector, it seems necessary to reduce and prevent the energy wastes. Windows include a significant part of this waste due to penetration of solar heat and radiation. The use of shading devices is evaluated as a suitable strategy in order to improve the energy utilization performance of the building. In this article, physical specifications of an office building in Kerman, Iran are modeled in Sketch Up software. Then by assigning materials to the building components in Open Studio software, the building is simulated. Finally, the building energy consumption in the presence of overhangs, movable shading devices and simultaneous use of them, is calculated in Energy Plus software. Results showed that the use of movable shading devices have better performance in reducing energy consumption compared to overhangs. In this regard, the interior shade has reduced the annual energy consumption of the building up to 17.37 %, compared to the base state (same building with no shades). On the other hand, overhang with a depth of 50 (cm) and movable shade saves 40.29 (GJ) in the annual energy consumption of the building, and shows the most reduction in energy consumption.

One of the main issues threatening hydraulic structures is the uplift pressure caused by the water flow in the porous media under the structures. Cut-off walls installed underneath a hydraulic structure can reduce the uplift pressure, by changing the water flow velocity, and as a result, the possibility of cracking and fracturing in the body of the structure. In this study, the effect of inclined cut-off walls with different angles of inclination (to the horizontal axis) underneath an irrigation canal (with laboratory dimensions) on the water flow velocity in the porous medium was investigated. The changes in the velocity due to the inclination were obtained using the Hydrus-2D numerical model. The velocity under the canal with no cut-off walls showed slight fluctuations, but increased owing to all the angles of inclination, reaching its maximum at the location of the cut-off walls. The most effective cut-off walls in increasing the velocity were the closest ones to the horizontal axis, i.e., those with angles of 15°, 30° and 165°, while the less effective angles were 90° and 120°, which were closer to the vertical line. The velocity just below the canal bottom increased with an increase in the angle, so that it changed by 18.05% and 209.45% due to the angles 15° and 165°, respectively. In fact, the cut-off walls performed better as they inclined from the earth’s surface to the canal bottom. In general, the angle of inclination should be selected based on the groundwater level, vulnerability of the walls and bottom of the canal, and economic considerations.

The purpose of this research is to investigate the effect of geogrid layers on the seismic behavior of stone columns. In this article, it has been addressed by both manual and numerical methods. In addition, the seismic behavior of stone columns covered with geogrid was investigated. By using numerical modeling and finite element method and by using two-dimensional Plexis software, the seismic behavior of stone columns with geogrid covering in the near and far field compared to normal stone columns was evaluated. The results show that the bearing capacity of a stone column increases with the use of a geogrid cover, and the smaller the diameter of a normal stone column or one with a geogrid cover, the lower the load capacity in a static state, and the use of a geogrid cover increases the bearing capacity of a stone column. In the case of plate loading, the smaller the diameter of the normal or geogrid-covered stone column is, the less load-bearing capacity it has in static mode, and the use of geogrid cover increases the load-bearing capacity of the stone column. Based on the results of numerical analysis, geogrid reduces the lateral deformation and displacement of stone columns during an earthquake. By examining different types of geogrid with different hardness, it was found that the type of geogrid had no effect on the seismic behavior of the stone column. Also, covering the upper half of the stone column with geogrid was enough to improve the seismic behavior of the stone column, and of course, this work is also economical.

In this research, the energy and exergy analysis of steam power-plant of the ninth refinery of South Pars Complex has been studied. Firstly, according to thermodynamic characteristics, pressure, temperature , flow rate and the type of fluid in terms of saturated water, dense liquid and super heat steam, enthalpy and entropy quantities were calculated and then using energy and exergy balance relationships, the losses and efficiency of various equipments have been calculated. The results of energy analysis showed that Boiler with 62.09 MW, Drum 107 with 17.75 MW and Deaerator with 14.17 MW have the highest energy losses and the efficiency of first law is 41%. Also, based on the results of exergy analysis, boiler with 94 MW, Heat exchanger with 5.297 MW and drum 107 with 5.233  have the highest amount of exergy destruction and the efficiency of second law is 33%. Also, the results showed that due to the use of the steam output from the turbine in other operating units in the studied refinery, the condensers have less exergy destruction and energy losses compared to other power-plants. In addition, by using the solution proposed in this research to heat input air of the combustion chamber through hot water coming out of the Continues Blow Down (CBD), it is possible significantly increase the exergy of the input air.

Facial feature recognition (FFR) has witnessed a remarkable surge in recent years, driven by its extensive applications in identity recognition, security, and intelligent imaging. The UTKFace dataset plays a pivotal role in advancing FFR by providing a rich dataset of facial images with accurate age, gender, and race labels. This paper proposes a novel multi-task learning (MTL) model that leverages the powerful Efficient-Net architecture and incorporates attention-based learning with two key innovations. First, we introduce an age-specific loss function that minimizes the impact of errors in less critical cases while focusing the learning process on accurate age estimation within sensitive age ranges. This innovation is trained using the UTKFace dataset and is specifically optimized to improve accuracy in age estimation across different age groups. Second, we present an enhanced attention mechanism that guides the model to prioritize features that contribute to more robust FFR. This mechanism is trained on the diverse and challenging images of UTKFace and is capable of identifying subtle and discriminative features in faces for more accurate gender, race, and age recognition. Furthermore, our proposed method achieves a 30% reduction in model parameters compared to the baseline network while maintaining accuracy. Extensive comparisons with existing state-of-the-art methods demonstrate the efficiency and effectiveness of our proposed approach. Using the UTKFace dataset as the evaluation benchmark, our model achieves a 0.62% improvement in gender recognition accuracy, a 2.35% improvement in race recognition accuracy, and a noteworthy 3.23-year reduction in mean absolute error for age estimation.

Given the economic and environmental importance ascribed to agriculture, there has been a rising focus on adopting greenhouse technology and renewable energy sources as sustainable and eco-friendly in this sector. Due to this emphasis, the current study utilized mathematical modeling of response surface methodology to analyze and optimization of the photovoltaic-thermal system’s performance of data obtained from a greenhouse. Through the use of Design Expert software and optimal factorial design, optimized treatments were achieved. The studied factors were time (ranging from 10 am to 3 pm), fluid types (pure water, SiO2, Al2O3, SiO2, and Al2O3- SiO2), nanoparticle concentrations (0.1%, 0.3%, and 0.5%) and the photovoltaic-thermal system location (inside and outside the greenhouse). The main objective of the optimization conditions was to maximize the energy parameters. The response optimization design was then examined for power, electrical efficiency, thermal efficiency, and total efficiency. The results demonstrated a strong correlation between the statistical model and the collected data (R2>0.90). Based on the experimental design factors, it was determined that the environmental condition of the system and the type of nanofluid had the most significant impact on the response. After implementing the design, the proposed optimal solution, with a desirability of 99%, involved utilizing a 0.5% concentration of Al2O3- SiO2 nanofluid in the system located outside the greenhouse at 3 pm.

Electrochromic Glazing (EC) has seen a significant surge in adoption today, primarily attributed to its pivotal role in enhancing visual comfort, mitigating excessive heat, regulating cooling and heating requirements, and curbing lighting consumption, especially within office buildings. Moreover, electrochromic glazing effectively contributes to glare control. This research aims to explore the impact of electrochromic glazing, as compared to conventional clear windows, on both the south and north facades, with the overarching goal of enhancing thermal and visual comfort within an office complex located in Mashhad. The research process unfolds in two key steps. Firstly, a comprehensive building simulation was conducted to assess daylight performance and gauge thermal and visual comfort using the GrassHopper plugin. Ubsequently, the Honeybee and Ladybug plugins were harnessed to evaluate the Discomfort Glare Probability (DGP) index and the Useful Daylight Illuminance (UDI) index. The findings of this study underscore the compelling advantages of electrochromic glazing over conventional clear windows as a prime choice to maintain balanced daylight levels throughout the day. In practice, using electrochromic glazing on both north and south facades of a building reduces the annual heating and cooling energy demand by 6.5 and 4.5%, respectively. Additionally, it has a significant impact on reducing intrusive light radiation and intolerable glare levels compared to reference transparent windows, with reductions of 40 and 34.52%, respectively.

Energy plays a pivotal role in economic development, yet achieving sustainable growth requires a balance between economic prosperity and environmental preservation. While past studies have concentrated on overall energy consumption efficiency and rebound effects, this study aimed to delve into the impacts of energy management enhancements within the five sectors (Agriculture, Transportaion, buildings, services, industry), with a specific focus on economic and environmental aspects. This study employed the Computable General Equilibrium (CGE) method and the social accounting matrix table to analyze various scenarios across industry, agriculture, and household sectors. Different levels of actions, ranging from limited to macro, were assessed within the framework of energy audits, with a specific emphasis on environmental concerns. Limited actions necessitate a 100% increase in initial investment, basic actions require a 200% increase, and macro measures involve a 400% increase. Discoveries from the Gams software highlight the financial viability of boosting energy efficiency to propel sustainable progress, leading to decreased energy requirements and CO2 emissions. The study indicates that shifting from basic to macro energy investments can successfully mitigate fossil fuel usage and carbon emissions, paving the way for a greener future.