Showing 26 results for Solid Waste
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.a Zazouli, A Mohseni Bandpei, A Eslami, A Sadeghi,
Volume 1, Issue 2 (3-2009)
Abstract
Background and Objectives: Recycling is one of the best alternatives in solid wastes management. Recycling has few benefits from the viewpoint of economics and environmental. Paper and cardboard are the valuable recyclable materials in solid wastes. The rate of paper recycling is 35% in world. The major production source of paper and cardboard wastes is private and governmental offices and organizations. To be informed about paper production is very important in the solid wastes recycling.Thus, the aim of this study was to determine production rate of paper and cardboard waste and also to determine paper recycling potential in the 20 head offices of Mazandaran province.
Materials and Methods: This study was conducted in the 20 head offices of at province center. The offices were selected by chance. This study was conducted four months in 2006. paper waste was separated after suspension of work. Collected material weighed on the sensitive scales. Separation and measuring was done for a week per month.
Results: The results showed that more than 2 tons of paper waste was produced in the twenty offices. The maximum and minimum of paper production was in education and recycling organization, respectively. The maximum and minimum of production rate was 2.08 and 0.192 kg per capita in month that was in the education and Jihad-e-Agriculture organization, respectively. Also the maximum and minimum of paper waste was produced at first work day of week (Saturday) and last work day of week (Thursday), respectively. However, it was not significantly (P >0.05). Paperrecycling operation and marketing was done in an office.
Conclusion: Findings of this study indicated that office solid waste management needs more notice in Iran. And also calculations showed that paper recycling is economical.
A.h Sayyahzadeh, M.t Samadi,
Volume 2, Issue 2 (9-2009)
Abstract
Backgrounds and Objectives: Municipal Solid Waste (MSW) management and planning without adequate and reliable data about its physical components and generation rate are not obtainable. Because of MSW collection and landfilling expenses, in last decades, reuse and recycle of its components as an environmental object have been considered.
Materials and Methods:In this research, in order to determine the possibility of source recycling application in Malayer and physical composition of MSW, samples were taken by Truck-Load method and cluster random sampling from autumn 2006 until summer 2007 and analyzed for physical components percents. The obtained data were analyzed by One-Way ANOVA and Tuky statistical test. Also, public partnership was investigated. Public opinion deliberation was accomplished by dividing the city into several clusters. Questionnaires were filled by oral interview conversation.
Results: The results showed that average daily generation rate was 138 Tons and 0.88 Kg per person per day. The average percent of recyclable materials was about 11% of total daily generated wastes. Also 99% of residents had positive response to source recycling plans.
Conclusion: In general, by planning of enforceable reuse and recycling programmes, could avoid of 15 Tons of recyclable materials burial and save 19 millions Rials each day.
M Farzadkia, S Salehi, A Aameri, A Joneidy Jafari, R Nabizadeh,
Volume 2, Issue 3 (11-2009)
Abstract
Backgrounds and Objectives: Over than 70% of solid wastes is consisted of food wastes with high putrecibility in Iran. Due to this regard, construction of composting factories for sanitary disposal or fertilizer production from solid wastes was very appreciated in our country. The objective of this research was to study on the quality and comparing of the compost produced by Khomain and Tehran compost factories.
Materials and Methods: This study was accomplished on the compost produce from Khomain and Tehran compost factories about 9 months. For investigation of chemical qualities of these materials, some indexes such as percentage of organic materials, carbon, nitrogen, phosphorus, potash and heavy metals consists of lead, cadmium, mercury and chromium were measured. Microbial quality of these compost materials were defined by assessing of the amounts of coliforms bacteria, salmonella bacteria and parasites ova.
Results: The average amounts of some indexes in compost of Khomain and Tehran were been: organic materials % (37.77, 29.80), carbon %( 22.14, 18.12), nitrogen% (2.08, 1.6), lead (229.6, 59.44 ppm), and chromium (70.2, 19.75), respectively. The microbial quality of these compost samples were agreement with class B of USEPA guidelines.
Conclusion: This study showed that quality of organic materials percent in Tehran's samples was better than Khomain's samples, but these indexes on these samples were lower than the grade No.2 of compost. The percentage of carbon, nitrogen and potash in these samples were desirable but, phosphorus amount were not in sufficient. The heavy metals especially lead and chromium in Tehran's samples were higher than Khomain's samples, but these samples were usually in agreement with guidelines of compost. Due to the defined microbial qualities, these samples could be used as well as amendment agents for poor soil.
M Panahandeh, M Arastou, A Ghavidel, F Ghanbari,
Volume 2, Issue 4 (3-2010)
Abstract
Backgrounds and Objectives: Landfill site selection is an important action in integrated solid waste management process. Difference criteria should be paid attention in site selection, so using of special methods are necessary to assimilate the criteria. In this research, GIS software and Analytical Hierarchy Process were used.
Materials and Methods: First of all, maps were built in considering to economical, social and environmental factors, in next step, each layer, was graded. Low grade showed non coordination or less coordination and high grade showed more coordination.
Results: Assimilate of graded map in AHP process, separates area into unsuitable, suitable and very
suitable parts.
Conclusion: Very suitable parts can have high priority in decision making and also suitable parts can have high priority for development projects in future.
M.b Miranzadeh, M Sabahi Bidgoli, A.r Zarfeshani, M Heidari,
Volume 4, Issue 4 (3-2012)
Abstract
Background and Objectives Autoclaving is one of the methods which sterilizes infectious solid wastes. Since variety of parameters such as temperature, time, and pressure influence autoclave performance, this study was carried out to evaluate the parameters and set optimum condition for the autoclave apparatus applied in Shahid Beheshti Hospital in Kashan.
Materials and Methods: In this descriptive-analytical study, the performance of subjected autoclave was surveyed based on biological index and through setting 144 tests. Variables were packaging type in two groups (open and wrapped), loading type in three groups (light, medium and heavy), and four temperature-time features in fixed pressure equal to 101 kpa. Biological index was ATCC 7953 which contained Stearotermophilus Geobacillus spores. Finally obtained results were analyzed by Chi-Square test.
Results: The results of statistical test showed that there isn't any meaningful relation between packaging type of waste, system loading, and efficiency of sterilization(P>0.05),while meaningful relation was found between system performance and variety states of temperature-time feature(P<0.05), illustrating temperature and time effects in fixed pressure on sterilization of solid waste.
Conclusion: Based on the results, the best autoclave operational condition for sterilizing infectious solid wastes are: temperature-time equal to 10 min-140°C and 15 min-134°C in fixed pressure of 101 kpa, respectively. It was also revealed that temperature-time condition suggested by manufactory, i.e. 20min-121°C, is not sufficient for complete sterilization of solid waste.
Mohammad Malakootian, Hassan Izanloo, Maryam Messerghany, Mohammad Mahdi Emamjomeh,
Volume 5, Issue 2 (10-2012)
Abstract
MicrosoftInternetExplorer4
Background and
Objectives: leachate from municipal solid waste
landfill is a strong sewage having hazardous toxic substances. It should
be
treated
by
choosing a
simple,
economical,
and eco-friendly method. The aim of this study is reduction of COD
from the
Qom City landfill leachate using electrocoagulation process.
Materials
and Methods: The experimental study
was carried out at bench scale using a batch reactor during 2010. We used a Plexiglas reactor having 0.7 liter
capacity, containing nine plate aluminum electrodes connected to a DC power supply (10-60V, 1-5A). Samples were
collected in the middle of cell at regular (every 10 minutes) time intervals.
The concentration of COD was determined using
a COD analyzer. The effects of different parameters
including current density (52.08, 69.44 mA/cm
2), electrolyte time (10, 20,30,40,50 and 60 min), and voltage range
(10, 20, 30, 40, 50 and 60 volt) were investigated.
Results: For a voltage of 60 V and electrolysis time 60 min, the COD removal
efficiency was increased from 48.7% for 52.08
mA/cm
2 to 77.4% for 69.44
mA/cm
2. The highest TSS removal
efficiency was obtained at the largest current input when the voltage and
electrolysis time were kept at 60V and 60 min respectively.
Conclusion: The results showed that the highest COD removal
efficiency (77.4%) was obtained when the current density was 69.44 Ma/cm
2 and the voltage and electrolysis time were kept at 60V and 60 min respectively. Power consumption for this removal level was measured to
be 431.26 kWh per kg COD removal. The results obtained revealed that the electrocoagulation
technology is an effective treatment process for landfill leachate.
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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.
Kamiar Yaghmaeian , Ali Akbar Roudbari, Saeeid Nazemi,
Volume 6, Issue 3 (12-2013)
Abstract
Background & Objectives: The aim of the study was to design and implement integrated solid wastes management pattern in Shahroud industrial area, to evaluate the results, and to determine possible performance problems.
Materials & Methods: This cross - sectional study was carried out for 4 years in Shahroud industrial area and the implementation process included: 1. qualitative and quantitative analysis of all solid wastes generated in the area, 2. determining the current state of solid waste management in the area and identifying programs conducted, 3. designing and implementation of integrated management pattern including design and implementation of training programs, laws, penalties and incentives, and illustrating and implementing programs for all factories, and 4. monitoring the implementation process and determining the results.
Results: Annually, 1,728 tons of solid waste is generated in the area including 1603 tons of industrial waste and 125 tons of municipal wastes. By implementing this pattern, two separated systems of collection and recycling of domestic and industrial waste were launched in this area. Moreover, consistent with the goals, the amount of solid waste generated and disposed in 2011 was 51.5 and 28.6 kg per 100 million Rials production respectively. In addition, 42 and 40% of the industrial waste and paper were recycled.
Conclusion: Results showed that implementation of this pattern, i.e. running source separation, training programs, capacity building, providing technical services, completing chain of industries and strengthening the cooperation between industrial estate management and industrial units could greatly reduce the waste management problems.
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.
J Karimi, M Sadeghi, E Fadaie, M.h Mehdinejad,
Volume 8, Issue 3 (12-2015)
Abstract
Background and Objective: Collection and disposal of waste has an important role in public health. Isolation and separation procedures at the origin is considered as one of the most important and least costly methods of isolation and separation of waste. This study was aimed to culture and educate those involved in recycling and waste reduction in the Kalaeh City using two educational methods. .
Materials and Methods: This semi-experimental study was conducted in Kalaleh City. In the social and cultural context, Kalaleh was divided into six regions. Using cluster sampling, regions were selected randomly. In each area, 120 samples were used. The first group was face-to-face trained and the second group received training through the training package. Waste collection period was 60 days. After this time, the questionnaires were again filled up and the impact of teaching methods were investigated.
Results: Face-to-face training resulted in increasing waste separation from 70.8 (before training) to 95%. Whereas, this figure in the group receiving training package increased from 57.5 (before training) to 86.7%. Waste recycling rate was between 0.6 to 1 Kg per person per week. These wastes included paper, glass, plastic, and metal containers. On average, the waste recycled in face-to-face training group and training package group was 91 and 83 Kg per week.
Conclusion: Knowledge, attitude and cooperation in waste separation increased after training in both groups. However, in the face-to-face training group, the knowledge and participation in waste separation was more compared with training package group. Continuous training and organizing waste separators could be helpful to re-use waste. It causes less pollution of the environment, reduce the transmission of diseases associated with non-systematic disposal of solid waste, reduce costs and increase awareness about the problems and issues of solid waste, and reduce the solid waste volume.
A Ebrahimi, M.h Ehrampoush, H Hashemi, M Dehvari,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objective: Predicting municipal solid waste generation has an important role in solid waste management. The aim of this study was to predict municipal solid waste generation in Isfahan through time series method and system dynamics modeling.
Materials and Methods: Verified data of solid waste generation was collected from Waste Management Organization and population information was collected from the National Statistics Center, Iran for the period 1996-2011. Next, the effect of factors on solid waste generation such as population, urbanization, gross domestic product was investigated. Moreover, the relationship between each of these factors was identified using generalized estimating equation model. Finally, the quantity of the solid waste generated in Isfahan city was predicted using system dynamics modeling by Vensim software and time series method by ARMA technique.
Results: It was found that population and gross domestic product have a significant relationship with the amount of solid waste with P value 0.026 and 0 respectively. The annual average of municipal solid waste generation would be 1501.4 ton/day in 2021 estimated by the time series method and 1436 ton/day estimated by the system dynamics modeling. In addition, average annual growth rate achieved was 3.44%.
Conclusion: According to the results obtained, population and gross domestic product have a significant effect on MSW generation. Municipal solid waste generation will increase in future. Increasing solid waste is not the same in different areas and methods. The prediction of the time series method by ARMA technique gives precise results compared with other methods.
M Ahmadi-Pirlou, M Ebrahimi-Nik, M Khojastehpour, Sh Ebrahimi,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: Solid waste management has always been one of the major challenges of large cities. Conversion of waste to energy in the form of biogas is known to be an appropriate solution. The aim of this study was to investigate the effect of total solids (TS) content and alkaline pretreatment on biogas production from municipal solid waste (MSW).
Materials and Methods: Experiments were done in 1 L glass bottles at 37 °C with different TS contents (5, 10, and 15%), each in 3 replications based on a completely randomized design. Comparison of means was used for interpretations of the result. The volume of the produced biogas, the amount of methane, and changes in pH were measured on a daily basis. In order for better mixing, the digesters were manually shaken for 30 seconds every day. TS, volatile solids (VS), carbon and nitrogen of the feedstock were determined according to APHA standard methods.
Results: The highest methane yield and VS reduction was observed in 5% TS. Therefore, this TS was chosen for alkaline pre-treatment. The results showed that pre-treatment with NaOH significantly improved biodegradability of MSW. In 25 days, the production of biogas was 30.38% higher than that of the untreated digester. The highest methane yield was 83.35 mL/g TS and 132 mL/g TS from the control and the pretreated digesters, respectively.
Conclusion: The results of the lab experiments showed that the TS of 5 % and the alkaline pre-treatment, significantly improved biodegradability of MSW and consequently increased biogas and methane yield.
Ma Ebrahimi-Nik, S Ghanbari Azad Pashaki, M Khojastehpour, A Rohani,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: In recent years, management and disposal of municipal solid waste has become a global problem and the most important environmental concern. Anaerobic digestion is a cost-effective solution for treatment of both solid waste and wastewater. The aim of this study was to investigate the positive or negative effects of calcium chloride content in anaerobic digestion process of municipal solid waste and leachate on biogas production.
Materials and Methods: Experiments with 8 levels of calcium chloride on co-digestion of municipal solid waste and leachate were investigated in 500 ml digesters under mesophilic conditions in a completely randomized design with three replications. Reactors with a ratio of substrate to inoculum of 2 (on VS basis) were operated and the volume of the biogas was measured daily. Volatile and total solids, carbon/nitrogen of waste, COD, BOD and heavy metals were measured by following APHA.
Results: The results of the experiment showed that the pH was decreased with increasing calcium chloride concentration. The highest amount of cumulative biogas production was obtained in CaCl2 of 2 g/L with the highest VS and TS reduction. Higher concentrations of CaCl2 (≥3 g/L) caused a reduction in the degradability of volatile and total solids and, as a result, a decreased performance of the digester.
Conclusion: The results clearly confirmed that the addition of calcium chloride was an effective solution to improve biodegradability in co-digestion of the MSW and leachate and consequently to reduce the total and volatile solids and to increase the amount of biogas.
Kh Faraji Mahyari, Sh Rafiee, Ar Keyhani, Z Faraji Mahyari,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Knowledge about the quantity of municipal solid waste (MSW) generation plays a key role in formulating policies of waste management. So far, different methods have been applied to estimate the quantity of waste generation. In this study, eight specific forms of mathematical functions were evaluated to predict waste generation by the regression analysis method based on population.
Materials and Methods: The significance test of each model and the existence necessity of predictor parameters were performed using the F- and t-statistic, respectively. The statistical indicators of determination coefficient ( ), adjusted determination coefficient ( ), root mean square error (RMSE), mean bias error (MBE) and mean percentage error (MPE) were used for model’s goodness of fit. The predicted determination coefficient ( ) was calculated to assess the predictive ability of models by method of Leave-one-out cross validation.
Results: The results showed that polynomial models of second order and more are not significant (at 0.01 level) despite good accuracy and are not suitable for long-term prediction. Linear, power and exponential models are best with equal to 0.942, 0.932 and 0.936 and equal to 0.904, 0.893 and 0.898 respectively. However, the uncertainty was greater in the exponential model.
Conclusion: The status of waste generation was investigated in four scenarios based on growth rate of population (increasing, fixing and decreasing births) at Tehran metropolis in 2021-2051. In all scenarios, annual generation and per capita of waste are increased to 2051. The daily waste generation will increase to 12317 ton in 2051.
Hamid Karyab, Faeze Karyab,
Volume 13, Issue 3 (11-2020)
Abstract
Background and Objective: Since industrial waste management requires accurate knowledge of quantity and quality of solid wastes, this study was conducted to assess quantitative and qualitative characterization of industrial solid waste in Qazvin province, Iran and investigate its related pattern management.
Materials and Methods: Based on the guideline of Iranian Environment Protection Organization, industries were classified into 10 groups. Then according to the abundance of industries in each group, 276 industries and 4 wastewater treatment plants were selected. The Basel Convention criterion was used to identify special solid wastes. Quantitative and qualitative characteristics and management pattern of industrial wastes were determined by referring to the industries and completing a researcher-made questionnaire.
Results: The total types of identified industrial solid wastes were 1726. According to the guideline of Basel Convention, 33.7% of identified wastes were classified as special wastes. The total amount of solid wastes was 38826 ton/month. The maximum solid wastes production was in the chemical industries with 14,380 ton/month. The recovery and recycling rates were 8.96 and 6.44%, respectively, and 36.44 % of industrial waste was sold directly.
Conclusion: The results of the study showed that the management of industrial solid wastes in Qazvin province does not follow a specific pattern. In addition, the quantity and the composition of solid wastes in the study area is a serious potential for environmental pollution and threatening human health. Therefore, it is necessary to establish a center responsible for industrial wastes management and design a centralized industrial waste disposal system.
Ali Daryabeigi Zand, Maryam Rabiee Abyaneh,
Volume 14, Issue 1 (5-2021)
Abstract
Background and Objective: Due to the increasing trend of municipal solid waste (MSW) production, if a suitable management system is not applied, it will lead to environmental pollution and endanger human health. The aim of this study was to compare different scenarios of waste management in Chalous city with life cycle assessment (LCA) approach and to select the most efficient method in terms of environmental adaptation.
Materials and Methods: After investigation of the quantitative and qualitative characterization of the produced wastes and the current waste disposal method in Chalous city, the obtained results were used to evaluate the life cycle of six different waste management scenarios; including the combination of four methods of composting, recycling, incineration along with energy extraction and sanitary landfilling. Emissions from various scenarios were assessed using IWM-2 model.
Results: The current system of municipal waste management in Chalus (scenario 1) with ecological index of 1.73+06 poses the highest pollution load into the environment. The inclusion of compost disposal methods in the organic waste sector and recycling of biodegradable materials significantly reduces the emissions of environmental pollutants by increasing the amount of materials for recycling and reuse, as well as preventing emissions from raw material production. The fifth scenario (60% compost, 30% recycling and 10% sanitary landfill) with ecological index of -2.00+05 was known as the lowest contamination scenario.
Conclusion: Considering that a high percentage of Chalous municipal solid waste composition is perishable materials (organic waste), simultaneous application of composting and recycling methods can be a suitable option for optimal management of wastes in Chalous city and play an important role in reducing the environmental pollution load.
Zeinab Mousania, Seyed Hassan Mousavi, Farzane Mirza Bayati, Reza Rafiee,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Various aspects including the environmental burdens, social and economic consequences of the waste management(WM) scenarios must be considered to come up with a comprehensive WM plan. Life Cycle Assessment (LCA) approach is a systematic method to quantify the environmental burdens of each WM scenario.
Materials and Methods: This study used an LCA approach to develop a decision support system to analyze different scenarios of WM. Local and global databases were used to develop a comprehensive life cycle inventory database. The model comes with a graphical user interface in Persian to make it easier to use by a wide range of customers. Finally, to evaluate the model, three scenarios were assessed in Karaj city, Iran.
Results: To the best of our knowledge, this model is the first attempt to automate the process of waste management scenarios evaluation in Iran. The model enables users to easily and quickly simulate a wide range of scenarios. All calculations will be carried out by the software in the background and the user only needs to determine his/her scenario of concern which is very easy owing to the user-friend GUI of the software. The model was evaluated by analyzing the current WM in Karaj. The results showed that the waste collection system is the main source of environmental pollution of the WM in Karaj city due to the inefficient system of the waste collection and poor fleet fuel efficiency.
Conclusion: This tool allows users to gather detailed information about the waste management systems. In this way, the user can make informed decisions about the most suitable waste management scenario in a city.
Zahra Khebri, Fatemeh Sadeghian, Fahimeh Faqhihi,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Dolochar is the residual ash from the production of sponge iron in the process of direct reduction of iron ore by the coal-based method. In Iran, this waste is transported to the nearest landfill. However, these methods are a major environmental concern due to the fineness of the waste and the presence of heavy metals in its composition. The aim of the present study is to investigate the methods of reusing dolochar in order to solve the environmental problem and further use it as auxiliary materials in applications such as road construction and wastewater treatment.
Materials and Methods: In depth investigation of the word “Dolochar” in Science Direct, SID, and MagIran databases showed that there is no long history of reusing it. Only 14 English articles were found, all of which were used in research; Therefore, the present article deals with the issue of reusing Dolochar in Iran for the first time.
Results: By reviewing previous studies, reuse of Dolochar has been classified into five sections. Dolochar use in wastewater treatment (removal of copper, chromium, paint, phosphate, nitrate, surfactant), removal of chromium from mine effluent (more than 94%), as a synthesis gas, as a filter medium (three times better than sand filters) and it is also used in construction and road construction (alternatives to aggregates).
Conclusion: The high capacity of Dolochar in waste absorption and wastewater treatment shows that it is necessary to reuse it in Iran instead of burying or leaving it in the environment.
Pantea Omrani,
Volume 14, Issue 4 (3-2022)
Abstract
Background and Objective: Nowadays, in metropolitan areas, principled and hygienic waste management is very important. Recycling is one of the most appropriate options in waste management. Hereof, the present study was aimed to investigate the possibility of using textile waste fibers in the manufacture of Medium Density Fiberboard (MDF).
Materials and Methods: This experimental study was performed on lab-scale. Fabric waste was prepared by separation method at source from a clothing manufacturer in Tehran and converted into fibers. Test boards were made with weight percentage of mixing textile waste fibers to industrial fibers at three levels of 0:100, 10:90 and 15:85, respectively, 10% urea-formaldehyde adhesive, with 16 mm thickness and 0.7 g/cm3 density by hot press. Then, properties of the boards were measured including bending strength, modulus of elasticity, internal bond, hardness, water absorption and thickness swelling. The results were analyzed with ANOVA test.
Results: The results of ANOVA showed that the effect of textile waste fibers on the bending strength, modulus of elasticity and swelling thickness of 2 and 24 hours of boards made at 5% probability level was significant. Additionally, the highest values of physical and mechanical properties are related to made boards with 10% of textile waste fibers.
Conclusion: The results showed that it is possible to make MDF with textile waste fibers. The use of wastes such as fabrics in the production of new functional products can be considered as one of the strategies to reduce waste and thus to maintain human health and the environment.
