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Publication Date: 2023/08/23
آب و فاضلاب (10245936) (3)pp. 57-71
Nowadays, the importance of ensuring the effluent standards of wastewater treatment plants is obvious. It is necessary to pay attention to the selection of the biological wastewater treatment process by considering different and diverse criteria. Because, the incorrect choice of the process increases costs and does not achieve the desired result. In this research, the technique of analytical hierarchy process and its combination with Taguchi method was used. By weighting and prioritizing the criteria and options by two groups of experts, including the scientific group and the executive group, the weight of each criterion and option was calculated. In the present study, options (in two cases including 7 conventional options and 7 advanced options), criteria (4 items) and comprehensive and complete sub-criteria (13 items) for selecting biological wastewater treatment processes in rural areas under various conditions have been considered. Finally, it was concluded that in both perspectives, the sub-criteria of providing disposal criteria and standards and the ability to reuse wastewater and climatic conditions were placed in the first and second priority. These sub-criteria received weights of 0.113 and 0.108 from the scientific point of view and 0.122 and 0.106 from the executive point of view. Also, the present study showed that the model of combining AHP and Taguchi method is a successful model for determining the method of biological wastewater treatment for various conditions. Finally, according to the results of this study, the prioritization of biological wastewater treatment options for wastewater treatment in Ahar village was done as a case study and the output results showed that the first priority of all experts is the artificial wetland method and MBBR, from a scientific point of view, Extended Aeration and ABR-Wetland, and in the executive point of view, artificial wetland and A2 O methods were prioritized (conventional and advanced methods, respectively).
Publication Date: 2020/03/20
آب و فاضلاب (10245936) (1)pp. 1-11
Chlorine is used as the most common disinfectant to prevent microbial growth in water networks. The concentration of chlorine in distribution systems or water conveyance lines is reduced due to two different types of bulk and wall decay. In this study EPANET software is applied to numerically simulate chlorine decay in the Isfahan water supply line from the Baba Sheikhali water treatment plant to Naein. Two methods are applied for simulation and the results are compared to the measurement. In the first method, chlorine simulation was performed taking into account the whole Isfahan water conveyance line as one section (integrated) and determining a bulk decay and wall decay coefficient for the entire conveyance line. In the second method, the line was divided into two sections (bisection) and decay coefficients of chlorine for each section was separately considered. To determine the bulk reaction rate, the bottle tests were performed at 6o and 18o Celsius corresponding to winter and summer. The results indicated that separating the line to two and applying independent coefficients and decay parameters to each part improves the results and the RMSE values are reduced from 0.09 to 0.03 in summer and from 0.064 to 0.025 in winter. Therefore, dividing the line in two or more sections substantially improves the accuracy of the simulation of chlorine decay.
Dehnavi, A. ,
Tavakoli aminian, S. ,
Rouhbakhsh meyari, M. Publication Date: 2018/01/21
آب و فاضلاب (10245936) (6)pp. 71-79
Hydrocyclones are used for removing suspended solids such as silt and sand from water. In this study, all the factors involved in the performance of hydrocyclones were initially identified and listed before they were optimized using the Taguchi experiment design method. It was the objective of the present study to optimize the efficiency of hydrocyclones in removing sand from water. For this purpose, 18 hydrocyclones were designed and constructed to test all the variables affecting their performance including hydrocyclone inlet, overflow, apex, and body diameters as well as cylindrical, total, and vortex finder heights. Minimum (20 mg/l) and maximum (100 mg/l) concentrations of total suspended solids (sand) in the samples from the water wells in Mashhad city along with the observed particle distribution were used in the optimization. Statistical analysis of the results showed that the ratio of the inlet and overflow diameters to that of the hydrocyclone was 0.225 and that the ratio of the apex diameter to that of the hydrocyclone was 0.15. Also, the ratios of the cylindrical and vortex finder heights to the total height of the hydrocyclone were 0.12 and 0.08, respectively. Under optimum conditions, sand removal efficiency varied from 95.9% to 98.4% in different experiments. This is while a value of 97.2±1.1% was obtained as the result of three tests in the hydrocyclone optimized in this experiment. Comparison of the mass removal efficiencies predicted by the Taguchi method and the values measured in the optimal hydrocyclone tests showed that both sets of data were very close and substantially high. Moreover, it was found that the geometric elements obtained in this study were generally in the range of minimum and maximum ratios proposed for hydrocyclones used in mining. These ratios may, therefore, be recommended for use in the construction of real-scale hydrocyclones for sand removal from water.
Publication Date: 2017/02/19
آب و توسعه پایدار (24235474) (2)pp. 55-62
This study investigates the amount of suspended solid particles in three drinking water wells, conducted several times per day in the city of Mashhad. The results have also been used for the review and optimization of tested hydro-cyclones. For this purpose, 18 different hydro-cyclones, based on the experimental design process of the Taguchi method, were designed and the affecting factors were investigated. These factors include inlet diameter, overflow diameter, apex diameter, body diameter of the hydro-cyclone, the cylindrical height, and the total height of the hydro-cyclone. For the optimization process, the maximum concentration observed within all samples from the Mashhad wells, equating to 100 mg per liter was used. The results of the laboratory study, for two repeats, showed that in optimum conditions, the mass removal efficiency of the suspended solids was up to 97.2 ± 1.1 percent. In these circumstances, the ratio of inlet and overflow diameter size to the hydro-cyclone diameter size was similar and equivalent to 0.225, and the apex diameter size ratio to the hydro-cyclone diameter size was 0.15. Also, the ratio of cylindrical and overflow height to the total height of the hydro-cyclone were 0.12 and 0.08 respectively.
Publication Date: 2026
Water Resources and Industry (22123717) 35
Wastewater from the baker's yeast industry contains high concentrations of organic and inorganic pollutants, necessitating effective treatment to minimize environmental impact. This study examines the falling film evaporator (FFE) and forced circulation evaporator (FCE) as single-effect units, as well as their combined performance in a multi-effect evaporator (MEE). To evaluate the performance of these systems, concentration reduction (C-RE), pollution load reduction (PL-RE), and grey water footprint reduction (GWF-RE) metrics are applied. Additionally, a new energy-based indicator is introduced to measure energy consumption per unit of pollutant reduction (ECI-PL) and grey water footprint reduction (ECI-GWF), providing a broader perspective on treatment sustainability. Based on C-RE, FFE removes 98.9 % of total phosphorus (TP), 94.4 % of biochemical oxygen demand (BOD5), and 93.5 % of chemical oxygen demand (COD), while FCE achieves the highest total nitrogen (TN) reduction at 32.8 %. GWF-RE for TP is observed at 99.4 % in FFE, 91.5 % in FCE, and 94.2 % in MEE. Energy consumption analysis reveals that the ECI-PL for TP removal ranges from 297 to 2560 kWh/kg. Despite its high energy demand, this process effectively reduces pressure on receiving water bodies, preserving between 617 (FFE) and 631 m3 (MEE) of freshwater for every kg of TP removed. These findings demonstrate that advanced evaporator systems effectively reduce the ecological footprint of baker's yeast wastewater, enhancing environmental sustainability. The results show that FFE is the most efficient in pollutant removal while maintaining lower energy consumption; however, TN reduction remains limited in this system. © 2025 The Authors.
Publication Date: 2025
Cleaner Environmental Systems (26667894) 19
The stress exerted on aquatic environments by wastewater discharge outlets, including those from industrial parks, can be quantified through a refined assessment of the grey water footprint (GWF). The conventional total GWF (TGWF), widely used in practice, sums the GWFs of mixed outlets without identifying a critical pollutant (CP), which is essential for effective pollution control and management strategies. A novel methodology was developed to calculate the weighted total grey water footprint (W-TGWF), integrating all discharge outlets by considering dilution effects and identifying the final CP. This study, conducted over four months from October 2022 to January 2023, evaluated TGWF and W-TGWF simultaneously for mixed outlets of treatment processes, Activated Sludge (AS) and Membrane Bioreactor (MBR), operated in parallel to treat wastewater from an industrial park in Isfahan province, central Iran. The mixed influent wastewater at the equalization tank, representing the total inlet GWF, ranged from 1.55 to 2.06 million cubic meters per month (MCM/month). For mixed outlets, W-TGWF consistently yielded lower values than TGWF, showing reductions of 22 %, 13 %, 26 %, and 5 % from October to January. The periodic average W-TGWF was 15,304 m3/month based on NH4 as the CP. In contrast, TGWF reached 18,909 m3/month, 24 % higher, due to the simultaneous influence of NH4 and F parameters without definitive CP identification. These findings show that TGWF tends to overestimate environmental stress and obscure pollutant prioritization. The weighted approach offers a more accurate and ecologically meaningful framework for assessing mixed GWFs, with direct implications for water management and regulation. © 2025 The Authors
Publication Date: 2025
Scientific Reports (20452322) 15(1)
This study developed a new framework based on grey water footprint (GWF) to inclusively evaluate and compare the industrial wastewater treatment plants (WWTPs). The conventional approach typically reports the efficiency of treatment systems on abating the concentration of each pollutant, individually. As an alternative, GWF can simultaneously include multiple pollutants, pollution loads, and regional water quality standards in calculations. These advantages are critical for assessing an industrial WWTP treating complex wastewater, with hazardous pollutants and variable inflow. Moreover, we introduced four innovative criteria based on GWF and improved it as a multi-functional index. To verify the applicability of the proposed method, we chose two operating units in parallel, the activated sludge (AS) and membrane bioreactor (MBR), as case studies treating real industrial wastewater. Samples were obtained from both treated and untreated wastewater. 36 pollutants were examined and used for GWF accounting in different scenarios. These scenarios were based on different maximum allowable concentrations (Cmax). Multi-pollutant GWF reduction (%) was the first index evaluating the overall removal efficiency. The AS with 93.1% average GWF removal could outperform MBR with 87.1% removal. Operational reliability was the second index, showed that AS could reduce GWF variations from inlet to the outlet with 83.7% efficiency, while it was 77.5% for MBR. The third index was GWF per carbon footprint (GWCF). It quantified the equivalent abated stress from water bodies per increased pressure exerted by emitting greenhouse gas (GHG) during wastewater treatment. The GWCF of AS was 347.8 m3/kg-CO2 indicating a superior efficiency over MBR with 84.9 m3/kg-CO2. It means that MBR relatively emitted more GHGs for reducing less GWF. Heavy metal pollution reduction (HPI) was the fourth index quantified based on GWF. It evaluated the particular performance of treatment systems for abating hazardous pollutants. The AS with an average HPI of 56.7% outperformed MBR with 50.4% efficiency. Therefore, this study showed that GWF is a versatile and applicable index and can provide a more holistic framework for evaluating and comparing wastewater treatment units. © The Author(s) 2025.
Publication Date: 2025
Environmental Monitoring And Assessment (01676369) 197(11)
Proper waste management is crucial to address the severe environmental issues that have emerged in recent decades. A prominent and extensively employed approach to tackling this challenge involves the utilization of life cycle assessment (LCA), which allows for a comprehensive evaluation of the environmental impacts associated with a particular system or product. This study used the LCA technique to determine the most effective waste disposal method in Isfahan, Iran. Six scenarios were examined, incorporating various processes such as landfilling, composting, anaerobic digestion, RDF incineration, and pyrolysis. The IWM2.0.6 model was employed to calculate energy usage and emissions for each scenario, while life cycle impacts were assessed using the SimaPro software and the IMPACT World+ method. Based on the results, landfilling has fewer negative impacts on human health than thermal treatment techniques like RDF incineration and pyrolysis. In addition, anaerobic digestion significantly reduces environmental impacts on ecosystem quality and human health. As a result, Scenario-4, which combines 28% manual separation (2% sent to recycling and 26% rejected to landfill) and 72% anaerobic digestion (39% biogas and leachate, 17% compost, and 16% rejected to landfill), achieved the lowest normalized environmental impact, with −4.06 × 103 for ecosystem quality and −1.88 × 103 for human health. Consequently, Scenario 4 was selected as the most suitable waste management alternative for Isfahan. Overall, using a life cycle assessment (LCA) can considerably assist in choosing the appropriate waste management strategy and positively impact the environment. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.
Fowzi, M. ,
Ebrahimpour, K. ,
Dehnavi, A. ,
Jamshidi, S. ,
Andaluri, G. Publication Date: 2025
Environmental Research (10960953) 284
The increasing abundance of microplastics (MPs) in water and soil has raised significant environmental concerns. This study evaluated the abundance and ecological risks of MPs in compost produced from three composting facilities (S1–S3) in Isfahan province, central Iran. Monthly samples were collected over a year, and MPs were extracted using an adapted protocol involving organic matter digestion with 0.05 M Fe (II) solution and hydrogen peroxide (H2O2), followed by density separation using saturated zinc chloride (ZnCl2). Despite rigorous methods, limitations remain due to the lack of a global standard and inherent errors in existing MP extraction protocols. The extracted MPs were analyzed under a stereomicroscope, and polymer types were identified via Micro-Raman spectroscopy. Ecological risks were assessed using established indices, including the Polymer Hazard Index (PHI), Pollution Load Index (PLI), and Potential Ecological Risk Index (PERI). The results revealed that the average MPs abundance in S1, S2, and S3 were 44,267 ± 7,240, 38,500 ± 6,130, and 34,267 ± 5297 items/kg dry compost, respectively. MPs larger than 1000 μm accounted for 41 %–49 % of the total, with fragments being the most prevalent shape (49 %–51 %). Polyethylene terephthalate, polyethylene, and polyolefin were the dominant polymers in all facilities. The ecological risk indices indicated high levels of risk in all three composting sites, with potential implications for agricultural soils, soil fertility. MPs in compost may enter the food chain, raising concerns for ecosystem health. These findings underscore the significant MP contamination in compost and highlight the need for improved solid waste management strategies to reduce plastic pollution. © 2025
Publication Date: 2025
Energy Reports (23524847) 14pp. 2593-2606
Water distribution networks (WDNs) often face challenges such as excessive pressure, leakage, and energy loss. While pressure-reducing valves (PRVs) are commonly used for pressure management, they dissipate energy that can otherwise be recovered. To address this, this study investigates the use of pumps as turbines (PATs) for pressure management while simultaneously generating energy. The hydraulic and energy performance of PRVs and PATs is evaluated using both demand-driven analysis (DDA) and pressure-driven analysis (PDA) through 24-hour extended period simulations (EPS) in the Jowitt network. Three PAT selection approaches are tested, based on maximum, average, and minimum 24-hour discharge values. Results show that selecting PATs based on average discharge consistently yields the highest energy production, increasing from 33.39 kWh to 107.42 kWh in DDA and from 44.88 kWh to 114.9 kWh in PDA, as the number of PATs increases from one to five. However, PRVs achieve greater leakage reduction and maintain lower pressure heads. Overall, the findings highlight the trade-offs between energy production and pressure control, demonstrating that PATs can serve as a sustainable alternative to PRVs when optimally selected. Moreover, PDA provides more realistic outcomes than DDA, particularly under pressure-sensitive conditions. This study provides a decision-making framework for integrated pressure and energy management in urban water networks. © 2025 The Authors
Publication Date: 2024
Environmental Science and Pollution Research (09441344) 31(32)pp. 45264-45279
This study used an integrated approach to mainly assess the water quality of paddy field during cultivation and quantify its equivalent ecological damages. Accordingly, an isolated pilot area with 0.6 ha and subsurface drainage pipes was prepared for flow measurement and multiple pollutant examination (DO, EC, pH, COD, TKN, TN, TP, NO3, butachlor) under controlled condition during 94 days of rice cultivation. Based on life cycle impact assessment (LCIA) database, the indices of ReCiPe (2016) were used to convert the examined nutrient and herbicide pollution. Results showed that TKN and TP were significant pollutants and reached the maximum concentrations of 7.2 and 4.9 mg/L in pilot outflow, respectively. Here, their average discharged loads were 56.2 gN/day and 45.3 gP/day. These loads equal leaching 8.5% and 9.4% of applied urea and phosphate fertilizers, respectively. The nutrient export coefficients were 8.4 kgN/ha and 6.8 kgP/ha. Nevertheless, the majority of this pollution was transferred by inflow. The net export coefficients were 0.3 kgN/ha and 2.6 kgP/ha while net leaching rates were 0.3%TN and 3.3%TP. The trend of combined ecological damages also showed that the 11–17th day of cultivation imposed the highest ecological risks. The state-of-the-art index of ecological footprint per food production estimates the equivalent ratio of lost lives by impaired ecosystem against lives saved from starvation. This index showed that 7% of the potential of produced paddy rice in this area for saving lives would be spoiled by releasing pollution to the terrestrial ecosystem in the long term. Yet, it can be enhanced as a matter of direct discharge to the freshwater. Therefore, using suitable agricultural operations or improving farm management practices for pollution abatement or assimilation potential is highly recommended. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.
Zekri, E. ,
Dehnavi, A. ,
Nasseri, M. ,
Majed, V. ,
Zarandi, S.M. Publication Date: 2024
Environment, Development and Sustainability (1387585X)
Iran, as a developing country, recently regards the reduction of GHGs emissions from waste sector as one of the important strategies in national sustainable development planning. Therefore, it is crucial to understand the effects of Municipal Solid Waste (MSW) management on GHGs mitigation potential. For this purpose, an integrated system dynamic model was developed to evaluate the environmental impacts of Official Development Plans (ODPs) regarding MSW. To demonstrate its applicability, Isfahan province in Iran is selected as a case study. The results show that ODPs on waste sector have adverse effect on GHGs mitigation. Which means that short, mid and long-term ODPs will increase GHGs emissions by about 71%, 80% and 152%, respectively. In all ODPs scenarios, aerobic fermentation (AF) method accounted for nearly most of GHGs emissions, at 95%, 78% and 34% in short, mid and long-term ODPs, respectively. Other treatment methods such as landfilling, anaerobic digester (AD), and incineration are very small sources of GHGs emissions, accounting for only less than 10% combined. Scenario analysis further indicates that Waste to Energy (WTE) method of compost gas utilization in AF is the most effective and adoptive measure in reducing GHGs emissions from MSW treatment, leading to about 34% and 22% of reduction compared with mid and long-term development scenarios, respectively. © The Author(s), under exclusive licence to Springer Nature B.V. 2024.
Publication Date: 2024
Environmental Footprints and Eco-Design of Products and Processes (23457651) 3512pp. 7-55
Industry drives economic activity by converting raw materials into products within an extensive network of factories. These are segmented into specialized sectors, each focusing on distinct products or services and employing specific processes and technologies that contribute to the society and the economy. While these sectors are essential for development, they also generate industrial wastewater. This wastewater is a mix of discharges containing harmful elements such as heavy metals (HMs), including chromium (Cr) and zinc (Zn), as well as other pollutants like chemical oxygen demand (COD), biochemical oxygen demand (BOD), and nitrogen and phosphorus compounds, which pose risks to both aquatic and terrestrial ecosystems. Understanding and mitigating the water quality impacts of these industries are crucial for their cleaner production. Notably, sectors such as textile and dyeing, metal-working, food and dairy production, chemicals, plastics, and electrical and electronics manufacturing make extensive contributions to the industrial water footprint (WF). The WF of a product is the total volume of water used to produce it, summed over the various steps of the production chain. Industries exert significant pressure on water bodies due to their excessive water consumption. This is particularly evident in sectors like textile and dyeing or food and dairy units, which require substantial amounts of water for production, cleaning, and packaging. Moreover, these enterprises introduce a wide range of pollution. For example, textile and dyeing industries discharge contaminants such as copper (Cu), lead (Pb), and COD, while metal-working industries release HMs like Cr and Pb during cooling and processing. Since WF represents the water used in production, the combined water usage and pollution discharges of these industries can increase the overall WF of the industry, posing substantial environmental challenges. The industrial WF is accounted for based on water quantity and quality, through the blue WF (BWF) and grey WF (GWF). The BWF represents the water used in manufacturing and direct freshwater consumption during production processes, while the GWF accounts for pollutants discharged into water bodies, impacting water quality and ecosystems as a result of industrial activities. In addition to the principles and methods, this chapter explains the calculated industrial WF of an industrial park located in Isfahan Province, Iran. It covers an area of 3.09 km2 and includes 554 units: iron and metal-working, textile and dyeing, chemical and fertilizer production, food and dairy production, cellulose industry and pulp and paper, electrical and electronic, administration and other industrial units, and non-metallic minerals. For its GWF assessment, multiple pollutants were evaluated over a period of 6 months (October 2022 to March 2023). Regarding the production yields of the Industrial Park, the average WF of production (WFP) is 1.76 m3/ton, derived from a net BWF of 1668 ± 54 m3/day and a GWF of 2.155 ± 0.285 million cubic meters (MCM)/month, attributed to NH4. Based on the analyzed conventional pollutants, the dilution factor indicator (Df) measured how many times polluted water needs to be mixed with fresh water to achieve a safe concentration level, which is typically around 50 times for NH4 in this study. It has been argued that the industrial WF faces various challenges in standards, experimentation, and accounting. Furthermore, mitigating GWF and WF requires a more holistic approach, incorporating technological innovations, recycling initiatives, and sustainable practices. Although these challenges and future trends, as well as the methods applicable to the industrial park, are discussed in this chapter, they are also calculable for various and specific individual industries. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.
Publication Date: 2023
Agricultural Water Management (18732283) 282
Grey water footprint (GWF) is one component of water footprint (WF). It considers multiple pollutants and water quality regulations when determining the amount of freshwater required to assimilate the pollution load discharged by agricultural production into the receiving water body. This indicator is typically estimated for accounting the WF of agricultural productions including paddy rice. This study evaluates the GWF of irrigated paddy rice (IPR) through sampling multiple pollutants in both the inflow and drainage of a pilot area, simultaneously. It aims to find a realistic range for the GWF of IPR and emphasize the impacts of pollutants, regulations (Cmax), and inflow (Qin) variations. For this purpose, an isolated subsurface drained farm in northern Iran was chosen as a pilot area where 32 samples from inflow and outflow were taken during the cultivation period (94 days). Here, the concentrations of electro-conductivity (EC), dissolved oxygen (DO), chemical oxidation demand (COD), nitrate (NO3), total kjeldahl nitrogen (TKN), total phosphorous (TP), total nitrogen (TN), and butachlor herbicide, as well as irrigation and drainage volume were investigated. Cmax was examined through three regulation scenarios: strict (S1), normal (S2), and lenient (S3). In addition, Qin was measured by the methods of water balance and SCD-USDA. Results show that TP was most critical in paddy rice GWF (S1-S2), while DO can be an alternative critical parameter in S3. Based on calculations, GWF was ultimately varied between 1109 and 8079 m3/ton in all scenarios. It incorporated a significant share in WF as its ratio varied between 46% and 86%. Cmax showed relatively higher impacts on GWF comparing with the precise calculation of Qin. Moreover, calculating the net pollution loads of multiple pollutants discharged from paddy field was recommended for higher accuracy. As a result, a range for GWF is introduced instead of an absolute value that can be updated by further case studies. © 2023 The Authors
Publication Date: 2022
Water Practice and Technology (1751231X) 17(12)pp. 2485-2498
In this study, the Taguchi method was applied in order to design experiments and optimize the performance of mini-hydrocy-clones by closed underflow for sand removal from well water. To optimize the hydrocyclones, two indices, mass removal efficiency and the cut diameter, were used. The first index analysis results showed that under the optimum conditions, the overall mass removal efficiency of solids will be up to 98.4%. An analysis of cut diameter data illustrated that under optimum conditions, the predicted cut diameter will be about 12.7 μm, while this diameter was estimated at about 16.3 μm under optimum mass removal efficiency conditions. The actual values of mass removal efficiency and cut diameter were determined at about 97.2 + 1.1% and 14.5 + 0.7 μm, respectively, for hydrocyclone manufacturing on the basis of mass removal optimum conditions. The use of the traditional estimation models such as Plitt, modified Plitt, Luz, and so on, which are applied for mining and mineral processing, illustrated that the estimated cut diameters were about 7.9, 8.4, 8.2, 0.45, and 2.33 μm, respect-ively. This estimation represented that these models are not suitable to predict the cut diameter of the hydrocyclone with closed underflow. Further investigation revealed that only the scale-increasing model could well predict a cut diameter of about 15.4 μm. © 2022 The Authors.
Shumal, M. ,
Taghipour jahromi, A.R. ,
Ferdowsi, A. ,
Mehdi noorbakhsh dehkordi, S.M. ,
Moloudian, A. ,
Dehnavi, A. Publication Date: 2020
Renewable Energy (09601481) 146pp. 404-413
Refused Derived Fuel (RDF) could be considered as an alternative energy source, which not only helps to improve waste management, but also effectively reduce energy consumption and environmental pollution in huge industries. In the present study, the potential of energy valorization of rejected streams of municipal solid waste (MSW) processed in Isfahan mechanical and biological treatment (MBT) plant is investigated through RDF production. Therefore, various physical and chemical analysis of mechanical treatment rejects (MTR) and composting rejects (CR), as two streams being currently landfilled, were carried out. The results show that, RDF produced from both of these two streams could be classified as net calorific value (NCV): 3, Cl: 1 and Hg: 1 according to the European committee for standardization (CEN standard). Considering the amount of produced RDF from these two streams in Isfahan (300 t/d from MTR and 120 t/d from CR) and their NCVs, about 2 million GJ/year would be saved. As a result, in many cities of developing countries with the same condition like Isfahan, MTR and CR can be used as sources of RDF production and alternative fuels in the cement industry. © 2019 Elsevier Ltd
Dehkordi, S.M.M.N. ,
Jahromi, A.R.T. ,
Ferdowsi, A. ,
Shumal, M. ,
Dehnavi, A. Publication Date: 2020
Renewable and Sustainable Energy Reviews (13640321) 119
One of the most used methods for municipal solid waste (MSW) management is recovering energy from the organic fraction of municipal solid waste (OFMSW) through anaerobic digestion (AD) system. Not only in developed countries (with high source separation), but also in developing countries (with poor source separation), this energy recovery technology can be interested. In many countries with mixed MSW like Iran, a mechanical separation (trommel screen, magnet, etc.) is used as a simple and efficient method to separate OFMSW. In this study, three main goals are followed; firstly, Selection of a suitable AD system (wet anaerobic digestion (WAD) or dry anaerobic digestion (DAD) and mesophilic or thermophilic)) according to physical and chemical composition of under-screen fraction of MSW and climate conditions. Secondly, evaluation of biogas energy potential of under-screen fraction of Isfahan municipal solid waste (USFIMSW), as one of the major cities of Iran is followed. Finally, it offers to use the results obtained in other developing countries with similar conditions in Isfahan. The physical analysis shows that about 70% of Isfahan MSW consists of the organic fraction (OF) which can be used in the AD system. Also, the value of total solid (TS), volatile solid (VS) and thereby VS/TS for the under-screen fraction of MSW changes seasonally between about 29% and 35.5%, 21%–25.5% and 64%–84%, respectively. The results show that in cities with a low source separation (due to the presence of hazardous materials in the under-screen fraction of MSW), high TS and dry climate like Isfahan, the use of DAD is more appropriate. According to bio-methane potential (BMP), TS and VS analysis, the average amount of methane yield, without purification of USFSMSW, is about 322.7 Nm3/t VS which can be increased by various steps in pre-treatment, feedstock preparation and co-substrate. © 2019 Elsevier Ltd
Publication Date: 2019
International Journal of Water (17415322) 13(3)pp. 236-247
Increasing measurements costs for surface water quality assessment besides the need for continuous measurements will cause a dilemma in poor countries. Therefore, a new method is proposed to identify and predict minimum probable water quality index (MIP-WQI) and maximum probable WQI (MAP-WQI) values instead of the traditional ones by combining available WQI data and Taguchi method. The water quality data of Bilghan station on Karaj River was used for prediction and comparison of the MIP-WQI and the MAP-WQI. According to the surveys and based on proposed method, the MIP-WQI and the MAP-WQI values based on 2008's data were estimated to be 61.6 and 87.4, respectively. Whereas from 2008 to 2010, actual minimum WQI values were 65.9, 69.8 and 69.3, respectively. In addition, actual maximum WQI values were 83.1, 77.2 and 75.6, respectively. Moreover, these probable indices could be more suitable to be used for water management especially in poor and underdeveloped countries. © 2019 Inderscience Enterprises Ltd.. All rights reserved.
Publication Date: 2017
Desalination and Water Treatment (19443994) 60pp. 106-113
For water quality assessment, there are several water quality indices, such as National Sanitation Foundation-Water Quality Index (NSF-WQI). These indices are determined by measuring several parameters in different samplings. Because the value of some of the measured parameters is constant during the different samplings; hence, these parameters can be measured in the earlier samplings and be used in the later one. The identification of these parameters can reduce the time as well as the cost of water quality evaluation. In this study, a new strategy by Taguchi method was used to propose a method (proposed method) to determine the mentioned parameters in a case study of Karaj River, Iran. For demonstrating capability of this strategy, water quality was calculated by standard (NFS-WQI), adjusted, and proposed methods and then the results were compared. Nine measured parameters in standard method were reduced to four by using the proposed method. In contrast to standard and adjusted methods that showed significant differences (p < 0.1), there were no differences between proposed and standard method results. Therefore, the proposed method may be recommended for water quality evaluation with reduction of the cost and the time. © 2017 Desalination Publications. All rights reserved.
Badalians gholikandi g., ,
Noorisepehr m., ,
Dehghanifard e., ,
Koolivand a., ,
Dehnavi, A. ,
Moalej s., Publication Date: 2012
International Journal of Environmental Science and Technology (17351472) 9(4)pp. 691-700
Several media have been used in treatment plants, however, their efficiency for turbidity removal, which is determined by qualitative indices, has been considered. Current qualitative indices such as turbidity and escaping particle number could not completely measure the efficiency of the filtration system; therefore defining new qualitative indices is essential. In this study, the efficiency of two different dual media filters in turbidity removal was compared in different operating condition using qualitative indices. The pilot consisted of a filter column (1-m depth) in which the filter-1 was consisted of a layer of anthracite (450-mm depth) and a layer of silica sand (350-mm depth); and filter-2 had the same media characteristics except for the first layer that was light expanded clay aggregates (LECA). Turbidities of 10, 20, and 30 NTU, coagulant concentrations of 4, 8, and 12 ppm and filtration rates of 10, 15, and 20 m/h were considered as variables. Results showed that the media of filter-2 is a suitable substitute for the media of filter-1 (P value < 0.05). Turbidity removal efficiencies in different condition were 79.97 ± 1.79 to 91.37 ± 1.23% for the filter-2 and 75.12 ± 2.75 to 86.82 ± 1.3% for the filter-1. The LECA layer efficiency in turbidity removal was independent of filtration rates and due to its low head loss; LECA can be used as a proper medium. Results also showed that the particle index was a suitable index as a substitute for turbidity and escaping particle number as indices. © 2012 CEERS, IAU.
Badalians gholikandi g., ,
Dehghanifard e., ,
Noorisepehr m., ,
Torabian a., ,
Moalej s., ,
Dehnavi, A. ,
Yari a.r., ,
Asgari a.r., Publication Date: 2012
Iranian Journal Of Public Health (22516085) 41(4)pp. 87-93
Background: Water filtration units have been faced problems in water turbidity removal related to their media, which is determined by qualitative indices. Moreover, Current qualitative indices such as turbidity and escaping particle number could not precisely determine the efficiency of the media in water filtration, so defining new indices is essential. In this study, the efficiency of Anthracite-Silica and LECA-Silica media in turbidity removal were compared in different operating condition by using modified qualitative indices. Methods: The pilot consisted of a filter column (one meter depth) which consisted of a layer of LECA (450 mm depth) and a layer of Silica sand (350 mm depth. Turbidities of 10, 20, and 30 NTU, coagulant concentrations of 4, 8, and 12 ppm and filtration rates of 10, 15, and 20 m/h were considered as variables. Results: The LECA-Silica media is suitable media for water filtration. Averages of turbidity removal efficiencies in different condition for the LECA-Silica media were 85.8±5.37 percent in stable phase and 69.75±3.37 percent in whole operation phase, while the efficiency of total system were 98.31±0.63 and 94.49±2.97 percent, respectively. Conclusion: The LECA layer efficiency in turbidity removal was independent from filtration rates and due to its low head loss; LECA can be used as a proper medium for treatment plants. Results also showed that the particle index (PI) was a suitable index as a substitute for turbidity and EPN indices.
University of Isfahan
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