Showing 17 results for Landfill
Ms Hassanvand, R Nabizadeh, M Heidari,
Volume 1, Issue 1 (10-2008)
Abstract
Background and Objectives: In the recent years Municipal Solid Waste (MSW) has been one of the most important environmental concerns to throughout regions of Iran. Sound MSW management for any area needs to the reliable data in which present the actual MSW condition in that area. The aim of this study is express of integrated view of MSW in Iran.
Materials and Methods: In this study we collect the data from various municipal regions of Iran, to represent the roughly integrated view of MSW management situation in Iran. In this paper quantity, average generation rate, physical composition, and types of disposal methods in all of municipal regions of Iran also were investigated.
Results: Results from this study has shown that the amount of MSW generated in all of the municipal regions of Iran was 10370798 tons per year, and the average generation rate of MSW was 0.64 kg/capita/day. Results showed that only 6% of MSW was recycled, 10% was treated at organic waste (composting) plants, and about 84% was disposed of in landfill.
Conclusion: According to obtained results from this study and compare MSW composition of Iran to some countries, its found that MSW properties in Iran is near to MSW properties in Low-income countries. Since the most of MSW in Iran contain organic fraction, there is a high potential to develop of composting industry.
M.j Zoqi, A Ghavidel,
Volume 2, Issue 2 (9-2009)
Abstract
Backgrounds and Objectives:A number of different technologies have recently been studied todetermine the best use of biogas, however, to choose optimize technologies of using biogas for energy recovery it is necessary to monitor and predict the methane percentage of biogas. In this study, a method is proposed for predicting the methane fraction in landfill gas originating from Labscalelandfill bioreactors, based on neural network.
Materials and Methods: In this study, two different systems were applied, to predict the methane fraction in landfill gas as a final product of anaerobic digestion, we used the leachate specifications as input parameters. In system I (C1), the leachate generated from a fresh-waste reactor was drained to recirculation tank, and recycled. In System II (C2), the leachate generated from a fresh waste landfill reactor was fed through a well-decomposed refuse landfill reactor, and at the same time, the leachate generated from a well-decomposed refuse landfill reactor recycled to a fresh waste landfill reactor.
Results: There is very good agreement in the trends between forecasted and measured data. R valuesare 0.999 and 0.997, and the obtained Root mean square error values are 1.098 and 2.387 for training and test data, respectively
Conclusion: The proposed method can significantly predict the methane fraction in landfill gasoriginating and, consequently, neural network can be use to optimize the dimensions of a plant using biogas for energy (i.e. heat and/or electricity) recovery and monitoring system.
M.t Samadi, M. H Saghi, M. Shirzad, J. Hasanvand, S. Rahimi,
Volume 3, Issue 1 (4-2010)
Abstract
Backgrounds and Objectives:In Iran , indicated that the municipal landfill leachate has been one of the major problem for environment. In the operations, leachate treatment is a very difficult and expensive process. Although, young leachate can be treated easily by biological treatment, COD removal efficiency are usually low due to high ammonium ion content and the presence of toxic compounds such as metal ions. Treatment of leachate is necessary.The aim of this study is reduction of Chemical Oxygen Demond (COD) and Total Suspended Solids (TSS) from hamedan city sanitary landfill leachate by three coagulants: alum, PAC and ferrous sulfate.
Materials and Methods: This experimental study was conducted to investigate the effect of treatment of landfill leachate by a coagulation-flocculation process. The effects of different amounts of coagulant and different pH values on the coagulation processes were compared.
Results:Result shown the high efficiency for reduction of CODby PAC in pH=12 and concentration of 2500(mg/l (62.66%), and by alum in pH=12 and concentration of 1000 (mg/l) (60%) , by ferrous sulfate in pH=2 and concentration of 1000 (mg/l) (70.62%). Also result shown the high efficiency for TSS removal by PAC in pH=12 and 2500(mg/l) concentration of PAC was 58.37%, with alum in pH=2 and 1500 (mg/l) concentration of alum was39.14% , by ferrous sulfate in pH=7 and 2500(mg/l) concentration of ferrous sulfate was 35.58%.
Conclusion:The best coagulant for COD removal is ferrous sulfate.The physico-chemical process may be used as a useful pretreatment step, especially for fresh leachates, prior to post-treatment (polishing) step for partially stabilized leachates.
M.j Zoqi, A Ghavidel,
Volume 4, Issue 1 (5-2011)
Abstract
Background and Objectives:. Owing to the non-seperated municipal solid wastes the leachate form in land fills contain high amounts of heavy metalls and toxic substances Hence, leachate treatment is a serious problem. In order to design leachate treatment and collection systems, estimation of quality and quantity of leachate is of high necessity. Hydrologic Evaluation of Landfill Performance (HELP) Model was used to estimate leachate generation in the lined landfill cells for a variety of conditions. The HELP program is a quasi-two-dimensional hydrologic model for conducting water balance analysis of landfills, cover systems, and other solid waste containment facilities. In this paper HELP program is used to predict leachate generating in Semnan landfill after its operational life.
Materials and Methods: HELP model use weather, soil and design data to estimate leachate quantity. The meteorological data were obtained from semnan Atmospheric Data Centre. Soil mechanics examinations in the landfill area were applied to achieve soil data. In addition, design parameters were based on Semnan landfill design specifications. Semnan landfill capacity is designed so as to accommodate municipal solid wastes generated during the next 25 years.
Results: In this study result indicated that precipitation and evapotranspiration has the most influenced on leachate generation increase and decrease, respectively. 82% of annual precipitation isn't percolated into Semnan landfill due to evapotranspiration. HELP Model simulations were indicated that the maximum and average value of leachate height above barrier layer is 36 and 3mm,respectively.
Conclusion: Semnan landfill is designed under minimum standard condition. Therefore, low height of leachate generated is due to area weather. The precipitation amount is low while the evapotranspiration amount is high in this area. High evapotranspiration is due to high temperature and solar radiation in Semnan landfill area. High evapotranspiration in the landfill cap caused 14.2% of the precipitation to infiltrate into the wastes and became leachate.
M Moeinaddini, M.h Tahari Mehrjardi, N Khorasani, A Danekar, A.a Darvishsefat, F Shakeri,
Volume 4, Issue 4 (3-2012)
Abstract
Background and Objectives: Solid waste municipal landfill can have injurious effect on society health, economic and environment. Therefore, spread evaluation in locating landfill is necessary to identifying the best places. The purpose of this paper is locating landfill for solid waste municipal for center of Alborz province.
Materials and Method: In this paper, suitable areas are identified for land filling solid waste municipal by weighted linear combination and cluster analysis in 20 years period. Thus, suitable areas were weighted by FAHP method. Those weights were used for ranking areas by DEA technique.
Result: Results showed among five landfill alternatives for solid waste municipal for center of Alborz province, alternative 1 is the best for land filling. This place is just 7 percent of total suitable places.
Conclusion: The approach are used in this article (combination method of fuzzy analytic hierarchy process & Data envelopment analysis) can be suitable for locating in other areas because when an option add or delete option ranking is not different with previous
Marzieh Mahtabi Oghani, Akbar Najafi , Habiballah Yunesi,
Volume 6, Issue 3 (12-2013)
Abstract
Background and objectives: Nowadays, landfilling is most common method in many countries owing to lower cost and adaptation to wide range of solid waste. Site selection of landfill requires evaluating several parameters such as municipal government requirements, environmental regulations and a large number of quantitative and qualitative criteria. The aim of current study was to compare AHP and TOPSIS in landfill site selection. For this purpose, two mentioned methods were applied to select suitable site in Karaj. Materials and methods: In present study, 4 candidate sites in south of Karaj were selected for landfill by overlaying data layers (digital maps) and query functions in Arc GIS 9.2. Prioritizations between alternatives were conducted by AHP and TOPSIS technique according to the criteria mentioned. Eventually, we compared and evaluated the AHP results and TOPSIS results with each other. Result: According to AHP, site prioritization was 3,2,4,1 respectively whereas, in the case of TOPSIS, it was ranked 4,3,2,1, respectively. These results showed that both methods are suitable to determine site priority. Conclusion: As in AHP, alternatives are compared with respect to goal and criteria, consequently it has better precision and higher accuracy and confidence compared with TOPSIS.
M Hatami Manesh, M Mirzaei, M Gholamali Fard, A.r Riyahi Bakhtiyari, M Sadeghi,
Volume 8, Issue 1 (8-2015)
Abstract
Background and Objectives: one of the most important environmental concerns is heavy metals emissions from human activities to natural ecosystems, particularly transfer to soil. The aims of this study were measured the concentrations of Cu, Zn and Cr in landfill soil and hospital waste ash of Shahrekord municipal solid waste landfill. Materials and Methods: Soil samples were collected from three sites: out of the landfill, municipal landfill and hospital landfill. In each site 2, 1, and 1 stations ware selected respectively and each sample was replicated in three times. Results: We found that there was a significant difference between concentrations of Cu, Zn and Cr in the landfills soil (95% confidence, P <0.05). Furthermore, the highest levels of Zn and Cu were detected in the hospital landfill and also for Cr in the municipal landfills. However, the concentration levels of heavy metals in all of the sites were in order as follows: Zn>Cu>Cr. Conclusion: High concentrations of metals determined in the present study represents the high application of these metals in the structure of municipal and hospital solid wastes and also their inaccurate separation. Thus, awareness about physical and chemical characteristics of municipal and hospital wastes and also the landfill soil is necessary for evaluating their effects on the soil quality and surrounding environments.
R Rafiee, M Moeinaddini, N Khorasani,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: The aim of this study was to assess the sensitivity and uncertainty analysis of a mass balance model to estimate the rate of aerobic processes in a landfill.
Materials and Methods: Monte Carlo simulation is a common method to evaluate uncertainty of the results of a model. Here, we used a Monte Carlo (MC) simulation. The data obtained from the experiments were used as a baseline. Considering a uniform Probability Distribution Function (PDF) within ±15% deviation, samples were taken from the baseline data. Using randomly selected inputs, model was executed for 1000 iterations and outputs were evaluated. Then, the total Sobol index for each input parameter was determined. The uncertainty of each output was presented by standard error and means observed in MC simulation.
Results: The results of this study revealed that while the uncertainty for the rate of composting process was mainly originated from the measured value of CO2 flux, the evaluated value for the rate of anaerobic digestion process was highly influenced by the value measured for CH4 emission flux. All inputs contributed equally to the uncertainty in the evaluated values for the rate of methane oxidation process. Although a variability of 15% was assumed for the model inputs, the mean value for the outputs from Monto Carlo simulations were close to those obtained by using base values that were in most cases within ±10% limit.
Conclusion: The majority of the uncertainty in the outputs came from the variability in the measurement of the flux of CH4 and CO2. The error in these parameters, however, can be minimized by increasing frequency and replicates of gas samples as these parameters are measured directly for each location.
Ma Zazouli, Z Karimi, R Rafiee,
Volume 12, Issue 4 (2-2020)
Abstract
Background and Objective: one of the major challenges in urban management in human societies is related to the collection, recycling and disposal of solid waste and sewage. Poor waste management causes pollution of water, soil and air. It will have a major impact on public health. The aim of present study was to investigate the current status and select the best options of management of municipal solid waste in Noor city (Mazandaran, Iran) using life cycle assessment (LCA) methodology.
Materials and Methods: This research considered with five scenarios: 1) Recycling, composting and unsanitary landfilling; 2) Recycling, composting and sanitary landfilling; 3) Recycling, incineration and sanitary landfilling; 4) Recycling, composting and anaerobic digestion, incineration, sanitary landfilling; 5) Recycling and unsanitary landfilling. The required data for life cycle assessment inventory were collected through reviewing resources, preparing of questionnaires, completing the questionnaire by staff, and field inspections.The life cycle inventory was approved by the IWM model.
Results: The scenario 5, which is the current situation in the region, had the highest environmental impact in terms of toxic emissions and ecological indicators among all the scenarios. Energy consumption in the scenarios 1 and 5 was higher than the unsanitary landfilling in comparison to the other scenarios. Accordingly, the scenarios 5 and 4 had the most and the least impact on methane gas production.
Conclusion: According to the ecological index, the fourth scenario including recycling, composting and anaerobic digestion, and sanitary landfilling was the best scenario. Fifth scenario with the highest pollution load was the worst scenario evaluated.
Milad Ghaffariraad, Mehdi Ghanbarzadeh Lak,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: One of the major challenges facing landfill operation is the pollution caused by leachate infiltration beneath the landfill site. Comprehensive leachate management requires knowledge of production rate and factors affecting it Therefore, in this study, HELP software was used to calculate leachate quantity and analyze input data.
Materials and Methods: After designing a landfill by the existing conditions in Urmia city, the quantity of leachate was calculated using HELP software. Then, in different scenarios, the effects of precipitation, Curve number, and removal of the geomembrane layer on leachate production -were investigated. Finally, the impact of similar layer aggregation on the simulation process was discussed.
Results: According to the results, 7.67% of precipitation is converted to leachate. NO significant correlation was observed between precipitation and leachate production in a short period of time due to the absorption of rain by landfill layers. However, for the long term, as the absorption capacity was reached leachate produced. With increasing the Curve number from 70 to 90, leachate production decreased by 23%. Also, the removal of geomembrane from the final coating increased the amount of leachate by 78.46%. Furthermore, by replacing a 76cm dense clay layer instead of capping geomembrane layer, the same leachate generation rate was observed. Re- running the software after layer aggregation showed a slight difference in leachate estimation compared to the baseline state.
Conclusion: Leachate generation modeling and identifying influential parameters with the aim of HELP software, may be helpful in landfill leachate management prior to its construction.
Azad Mollaei, Reza Rafie, Mazaher Moeinaddini, Sayyed Hossein Khazaei,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: The purpose of this study was to use the HELP model to estimate the leachate generation rate and its pattern in a landfill located in the semi-arid region of Iran.
Materials and Methods: The input data for the model were collected through fieldwork. To evaluate the accuracy of outputs, the actual amount of leachate production has been measured on-site for 10 months. In addition, sensitivity analysis was conducted to find out the most important parameters in leachate generation in the landfill.
Results: The results showed that the model was able to estimate the rate of leachate generation with an accuracy of 75.5% and the correlation between the model's estimated values and actual values was 60%. In addition. the sensitivity analysis showed that the most important factors affecting the leachate generation in the landfill were waste moisture content and rainfall, respectively.
Conclusion: The model showed satisfactory performance in the prediction of leachate generation in the arid area. The model showed that the moisture content of the waste significantly contributes to leachate generation in Karaj landfill and therefore, it is suggested to identify and implement procedures to reduce the moisture content of the waste at the source of generation.
Mohamad Mehdi Ghorbaninejad Fard Shirazi, Sakine Shekoohiyan, Gholamreza Moussavi, Mohsen Heidari,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: Among the emerging contaminants, microplastics threaten public health. This study aimed to determine microplastic and mesoplastics in soil of residential areas adjacent to Tehran Landfill and assess its ecological risk.
Materials and Methods: The present descriptive cross-sectional study was conducted on 20 shallow and deep soil samples from residential areas near the Tehran landfill in July 2021. The microplastics were floated in NaCl and ZnCl2 solutions, and the mesoplastics were separated manually. The identification of physical and chemical properties of polymers was performed by stereomicroscope and FTIR analysis, respectively.
Results: The average amount of micro-plastics in shallow and deep soils estimated 76±34.98 and 24.7±19.79 particles/kgsoil, respectively. The average amount of mesoplastics obtained 5.25±2.91 and 3.55±1.09 particles/kgsoil, in shallow and deep soils, respectively. Paired-samples T-test showed significant differences between shallow and deep soil in terms of plastic particles (p<0.001). The most abundant microplastic particles were the fragment-shaped with the particle size of 0.1-0.5 mm and LDPE polymer types with the percentage of 37.75, 44.64, and 46.15, respectively. Mesoplastic particles, the 0.5-1 cm film-shaped particles and LDPE polymer types with the percentage of 62.76, 61.46, and 50.7 were found as the most prevalent. Microplastics and mesoplastics' potential ecological risks value in all sampling points was less than 150, indicating low ecological risk.
Conclusion: Despite the low PERI of microplastics and soil mesoplastics in residential areas, the Eri index for LDPE was high. Thus, Ecological risk is probable if control measures are not taken against plastic pollution.
Sayyed Hossein Khazaei, Mazaher Moeinaddini, Reza Rafiee, Nematollah Khorasani, Melanie L. Sattler,
Volume 15, Issue 3 (12-2022)
Abstract
Background and Objective: Various models have been developed to predict methane generation and emissions from landfills. Due to their simplicity, the minimum number of required data, and the accuracy of the outputs, First-order decay are the most common models to predict methane generation in landfill,. Three important parameters in modeling landfill gas generation using a first-order model are the total weight of waste buried in the landfill, the methane generation potential, and the methane generation rate constant. The purpose of this research was to accurately estimate the parameters of the first-order model and to optimize it for estimating methane generation in the landfill and also to develop the ILGAM software.
Materials and Methods: ILGAM model consists of two submodels: 1) the gas generation sub-model and 2) the methane oxidation sub-model. The methane oxidation sub-model is based on the MOT model. The gas generation sub-model is based on a first-order equation with an emphasis on the contribution of the aerobic process in the estimation of the ultimate methane potential of waste. The parameters of the equation were modeled using the latest available results in the literature. To evaluate the model, the actual methane emission and methane oxidation were measured in the Karaj landfill. The results of the model, along with a few common models, were compared with actual data obtained from the Karaj landfill.
Results: The ILGAM model predicted the gas emission from the Karaj landfill with an error of 5.8%. In contrast, LandGem, IPCC and CLEEN models predicted the methane gas emission from the Karaj landfill with an error of 74.4%, 40.2%, and 27.1%, respectively.
Conclusion: When compared to other models, the ILGAM model estimated the closest values to actual measurements for methane emission and methane oxidation in the Karaj landfill. Owing to its user-friend Graphical User Interface (GUI), the model can be easily executed in a wide range of landfills by entering a few easy-to-measure data in the field.
Ehsan Mohammad Hassani, Reza Rafei, Mazaher Moeinaddini, Niki Aghapour,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: One of the largest sources of methane emissions is landfills, and various models have been developed to predict landfill methane production and emissions. The main goal of this research is to utilize the inverse Gaussian model to estimate g methane greenhouse gas emissions and model it using field data. This study introduces a simple method to estimate the amount of methane emissions based on ambient methane concentrations.
Materials and Methods: In this research, the methane emission rates from landfill were estimated for warm (July) and cold (February) seasons using a sampling campaign from 27 stations and standard inverse Gaussian dispersion equations. Monte Carlo simulation was also employed. To determine the model, an optimization-based method, along with inverse scattering modeling, was utilized to process surface emission monitoring data.
Results: The model results indicated during the cold (February) and warm (July) seasons, the methane emission rates were estimated at 1696.99 and 16.53 g/s, respectively. These findings confirm that the methane production and emission during the cold season were lower than in the warm season, likely due to reduced temperature and bacterial activity.
Conclusion: The method used in this study, the inverse Gaussian dispersion model, can be applied to estimate methane gas emission rates from other landfills. However, it necessitates the permanent recording of data and the use of daily or weekly averages in calculations to mitigate potential errors and enhance the accuracy of modeling.
Saeed Karimi, Bahareh Rahimipour,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Waste management is a crucial aspect of sustainable city development due to the increasing population, urbanization expansion, and changes in consumption patterns. The purpose of this study is to identify the waste landfill in Bushehr city by considering the relationships between various criteria using the DANP (DEMATEL-ANP) method.
Materials and Methods: 17 criteria were identified to identify the suitable landfill. The weighting of these criteria was done by DANP integrated multi-criteria decision-making technique. The internal relationships of the criteria and the causal relationships between the criteria were also determined. Then, these weights were multiplied in the spatial layer of each of the criteria in the environment of geographic information systems.
Results: The most crucial criterion for selecting a suitable location for urban landfill is land use, followed by the criteria of distance from residential areas, tourist places, and the road. The study identified and evaluated five locations in Bushehr city as potential landfills based on these criteria. The eastern and southeastern parts of Bushehr city emerged as the most suitable locations for landfill among the evaluated sites.
Conclusion: The DANP model proves highly effective in identifying landfills and offers a framework for addressing issues related to waste landfill selection. This research can serve as a valuable guide for planning and locating waste landfills, providing a basis for addressing both theoretical and practical challenges associated with landfill management.
Nader Abbasi, Mohsen Mohammadi Galangash,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: Heavy metals are regarded as serious contaminants due to their toxicity, persistence in natural conditions, and ability to enter and accumulate (bioaccumulation and biomagnification) in food chains. The aim of this study was to investigate the concentrations of the heavy metals Pb, Cd, Cu, Zn, Cr, Fe and Ni in surface agricultural soils of the Miandoab landfill area.
Materials and Methods: In this study, 57 soil samples were collected from a depth of 0-20 cm. After preparing and digesting in the laboratory, the samples were analyzed using a inductively coupled plasma spectrometer (ICP-OES). The Ecological Risk Potential Index (EPRI), Earth Accumulation Index (Igeo), Principal Components Test (PCA) Pearson's Correlation, Cluster Analysis, and One-T-test were utilized. Statistical processing was conducted using SPSS software.
Results: According to the results of the single T-test, the average concentrations of Pb, Cd, Cu, Zn, Cr, Ni did not significantly differ from their background concentration in the soil (p≥0.05). A significant difference was pbserved only for Fe (p<0.05), indicating a geological origin for this element. The EPRI was within the low-risk range, with an average value of 46.95. PCA revealed that the first factor was positively associated with Cr, Pb and Fe; the second factor with Zn and Cu; and the third factor with Cd. Cluster analysis showed that Fe was predominantly influenced by natural resources. According to the land accumulation index, all metals, except Cu, were classified non-polluted or slightly polluted at stations 2 and 4.
Conclusion: The origin of elements is related to both natural and human factors. Specifically, Cr, Pb and Cd are more likely to originate from man-made sources, while Fe primarily comes from natural sources. The decrease in the concentration of metals can be attributed to continuous and annual ploughing, inactivity of the landfill, biological absorption by crops, soil leaching and transporting to lower depths.
Mohammad Hssanabadi, Mohammad Sadegh Hassanvand, Mohammad Khanizadeh, Sasan Faridi, Adel Mokammel, Bita Malekian Esfahani, Ali Ahmadi Orkomi, Fatemeh Momeniha,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The initial step in managing methane emissions is quantification. This study aims to comprehensively investigate the methods for estimating and measuring methane gas emissions in municipal solid waste landfills.
Materials and Methods: This systematic review includes studies published in English and Farsi between January 2005 and May 2023. English-language articles were included from PubMed, Web of Science, and Scopus databases, while Persian-language articles were included from SID, Majiran and Google Scholar.
Results: After evaluating the studies, 90 studies providing information on methods for measuring and estimating methane gas emissions in urban landfills were selected. The results showed that emission estimates based on widely used models like LandGEM and IPCC, despite being lower in cost and providing faster results, are often associated with relatively high uncertainty. Therefore, quantitative and qualitative methods of direct measurement are preferred for accurately determining methane emissions from landfills. The most commonly used methods for measuring greenhouse gases, especially methane from landfills, include direct reading equipment and closed flux determination chambers.
Conclusion: Estimating greenhouse gas emissions from primary sources allows responsible authorities to understand the current status of methane emissions and to formulate reduction strategies. The findings of estimated methane emissions from landfills can differ significantly from the actual measurements in some situations. Therefore, while these estimation methods are useful, fast and cost-effective tools, their inherent uncertainties should be considered when using them.
