Hassan Hashemi; Ehsan Gharehchahi; Mohammad Golaki; Amin Mohammadpour; Zohre Moeini
Abstract
Coronavirus disease 2019 (COVID-19) is a viral infection caused by SARS-CoV-2, first recognized in China and quickly became a global pandemic. The COVID-19 pandemic has been found to have positive and negative environmental impacts. Air, wastewater, and solid waste are some examples that show this pandemic’s ...
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Coronavirus disease 2019 (COVID-19) is a viral infection caused by SARS-CoV-2, first recognized in China and quickly became a global pandemic. The COVID-19 pandemic has been found to have positive and negative environmental impacts. Air, wastewater, and solid waste are some examples that show this pandemic’s consequences. The current review summarizes the interactions between the COVID-19 pandemic with air, water, wastewater, and solid waste. During the COVID-19 outbreak, air pollution, ambient noise, fuel, and energy consumption, have been reduced. On the other hand, air pollution has been shown to increase the risk of COVID-19; thus, there is a positive correlation between air pollution and the number of COVID- 19 cases. Moreover, the researchers have detected the SARSCOV- 2 in feces and wastewater. Therefore, exposure to SARSCoV- 2 is possible by utilizing untreated effluent and wastewater in irrigation or aerosol generation during specific wastewater treatment processes. Furthermore, monitoring SARS-CoV-2 in the wastewater allows us to detect the virus before it spreads in the community take the necessary measures, and implement effective policies. Changes in the composition and quantity of municipal solid waste (MSW) are typical results of the COVID-19 pandemic, as plastic waste generation has increased globally due to the higher use of disposable single-use plastic bags and packaging. Mixing infectious virus-infected waste with domestic waste has led to the terminus of waste recycling in many parts of the world due to its hazardous potential. Developing effective strategies based on the sustainable development approach may reduce the adverse effects of the COVID-19 pandemic and similar outbreaks in the future.
Masoud Yousefi; Kourosh Rahmani; Reza Jalilzadeh Yengejeh; Sima Sabzalipour; Gholamreza Goudarzi
Abstract
Background: The production and consumption of pharmaceutical compounds, including antibiotics, and their entry into the environment have raised concerns for experts. It is important to find appropriate methods for treatment of these pollutants from aquatic environments. In this study, nano-persulfate ...
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Background: The production and consumption of pharmaceutical compounds, including antibiotics, and their entry into the environment have raised concerns for experts. It is important to find appropriate methods for treatment of these pollutants from aquatic environments. In this study, nano-persulfate process using green synthesis of zero iron nanoparticles was used in decomposition of the antibiotic Metronidazole (MNZ). Methods: In this study, first, zero iron nanoparticles were synthesized using oak leaves. Then, the characteristics of these nanoparticles were determined using electronic images such as SEM, and TEM. In the experimental part of the study, the effect of operating conditions such as nZVI dosage, persulfate concentration and pH of the PS/nZVI process on degradation of MNZ in aqueous solution Was examined. Results: The results of this study showed that the PS/nZVI process had an acidic nature for removal of MNZ. The optimal conditions for this process were: the dosage of nZVI was 1.8 g/l, the concentration of persulfate was 1.5 mg/l, and pH was 3 for the degradation of 50 mg/l MNZ at contact time of 90 min. The maximum MNZ removal efficiency using PS / NZVI process was about 98.4 % in these conditions. Conclusion: It can be concluded that the synthesis of green zero iron nanoparticles is an economical and environmentally friendly method that can be used to remove MNZ from aqueous solutions.
Elham Asrari; Negar Daneshi
Abstract
Background: In recent years, the need for new methods of water treatment on an industrial scale in order to compensate the shortage of water resources has become imperative. Among different methods, the use of adsorption in order to remove aqueous contaminates, including synthetic dyes, has been so effective. ...
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Background: In recent years, the need for new methods of water treatment on an industrial scale in order to compensate the shortage of water resources has become imperative. Among different methods, the use of adsorption in order to remove aqueous contaminates, including synthetic dyes, has been so effective. Methods: In this research, removal of malachite green from aqueous solution by concrete modified with rubber powder has been studied. In order to achieve the maximum efficiency of malachite green removal, the impact of different parameters such as initial concentration of malachite green, pH, adsorbent dosage and contact time was studied using batch experimental method. Results: According to the results, optimum conditions of MG removal were pH of 9, initial concentration of 30 ppm, rubber powder dosage of 35% of sand weight, and contact time of 90 min. Results of compressive strength test have shown that compressive strength of concrete with 35 wt.% of rubber powder reduced 84.13% compared to simple concrete. The removal percentage of MG is 98.33% when the surface of concrete is covered by rubber powder. Experimental data corresponded with pseudo-first order equation with R2= 0.93, Langmuir and Freundlich adsorption isotherms with R2= 0.85 and 0.84, respectively. Real waste sample was used to confirm the application of concrete in ordinary conditions of wastewater basin in accordance with optimum conditions of kinetics wastewater. Elimination rate of MG happened in an optimum condition with real samples taken from industrial factory. Conclusion: Concrete modified with rubber powder has potentials for removal of MG dye from wastewater. Covering the concrete surface with rubber powder can be an innovative and useful solution for increasing the rate of elimination of pollutants and contaminants, cost reduction and accelerating the absorption process. Actually, it could be considered as one solution for managing waste rubber.
Amir Hossein Baghaie; Raheleh Mirzaee
Abstract
Introduction: In order to optimize the use of industrial wastewater, proper management practices should be applied for wastewater treatment. Thus, this study was done to evaluate the effect of iron slag enriched cow manure, zeolite and pumice on the sunflower Pb concentration in a soil irrigated with ...
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Introduction: In order to optimize the use of industrial wastewater, proper management practices should be applied for wastewater treatment. Thus, this study was done to evaluate the effect of iron slag enriched cow manure, zeolite and pumice on the sunflower Pb concentration in a soil irrigated with wastewater of battery factory. Methods: In this descriptive study, treatments consisted of applying iron slag (0, 1 and 2 % (W/W)) enriched cow manure at the rates of 0 and 30 t/ha, using zeolite (0 and 2 % (W/W)) and pumice (0 and 8 % (W/W), and sunflower irrigation with the wastewater of battery factory mixed with well water with the ratio of 1:1 and 1:2 (water/wastewater). After 60 days, the plant was harvested and the concentration of Pb and Fe was measured using atomic absorption spectroscopy. The SOD enzyme activity was also determined. Results: Application of 2% zeolite and 8% (W/W) pumice significantly decreased the Pb concentration of the soil irrigated with the wastewater at the ratio of 2:1 (wastewater/water) by 8.1%, respectively. The plant Pb concentration was also increased by 11.2 and 13.3%, respectively. The SOD enzyme activity showed a similar trend with the plant Pb concentration. Enrichment of cow manure with iron slag significantly decreased the Pb concentration of the plant that was irrigated with the wastewater at the ratio of 2:1 (wastewater/water) by 11.3% Conclusion: Iron slag enriched cow manure, pumice and zeolite significantly decreased the soil and plant Pb concentration of the soil and plant that was irrigated with wastewater.
Elham Asrari; Esmail Izadi Navan
Abstract
Background: The presence of quantities of dye chemicals in the textile industry effluent is clearly visible and harmful environmental impacts caused by chemical compounds are also as a noticeable challenge. Regarding this issue, control of the pollution has been considered. Methods: In this study, an ...
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Background: The presence of quantities of dye chemicals in the textile industry effluent is clearly visible and harmful environmental impacts caused by chemical compounds are also as a noticeable challenge. Regarding this issue, control of the pollution has been considered. Methods: In this study, an absorbent of Sodium Montmorillonite modified by Methylene Blue dye was used to remove Brilliant Red dye from the textile effluent. All batch experiments were carried out in 250mL of solution of 640 mg/L Methylene Blue with 2g of adsorbent and performed on a shaker with a shaking of 120 rpm; the precipitate was placed in an oven at 60◦C for 24 hours. The effective parameters on the adsorption including: pH, absorbance dose, dye concentration and contact time were optimized by using both one factor at a time technique and Central Composite Design method by designing 30 experiments with four variables (n= 4) and two levels (low (-) and high (+)). Results: The optimal values of the influencing parameters such as pH, absorbance dose, dye concentration and contact time were determined at 6, 0.3 g, 80 mg/L and 60 min with an approximate 92% removal percentage, respectively. The results illustrated that the process was more consistent with Langmuir adsorption isotherm and pseudo-second kinetics equation. Conclusion: The adsorption behaviors of the modified absorbent showed that the adsorption kinetics and isotherms were in good agreement with pseudo-second-order equation and the Langmuir equation, respectively. The potential for regeneration and reuse of the modified absorbent was proved by the desorption studies.
Mohammad Reza Samaei; Majid Nozari; Marziyeh Ansari Shiri; Mehdi Mokhtari; Asghar Ghasemi; Reza Rezaei Javanmardi
Volume 5, Issue 2 , April 2017, , Pages 44-50
Abstract
Background:Discharge of raw or treated wastewater containing linear alkyl benzene sulfonate (LAS) into the environment causes significant public health and environmental problems. The purpose of this study was the treatment of hospital wastewater using an intermittent cycle extended aeration system (ICEAS).Methods:Experiments ...
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Background:Discharge of raw or treated wastewater containing linear alkyl benzene sulfonate (LAS) into the environment causes significant public health and environmental problems. The purpose of this study was the treatment of hospital wastewater using an intermittent cycle extended aeration system (ICEAS).Methods:Experiments were carried out on Yazd Shohaday-e-Kargar hospital wastewater treatment system and samples were collected in a 2 month period from the influent and effluent of the system. The used pilot study carried out consisted of two zones: pre-react and main react zones. They were divided using a baffle wall. Firstly, wastewater enters a pre-react zone and then through the opening at the bottom of the baffle wall it enters the main react zone. The cycle time and flow rate for the system were considered 6 h and 2 L/h, respectively. Then, the necessary tests were performed on the system’s influent and effluent.Results:The removal of BOD5, COD, and LAS by ICEAS were 94.54%, 92.97%, and 84.99%, respectively. The averages of SVI, F/M, MLSS and MLVSS in the system were 113 mL/g, 0.086 Kg.BOD5/Kg.MLSS.d, 4327 mg/L and 3172 mg/L, respectively.Conclusions:This work showed the excellent efficiency of ICEAS to effectively remove BOD5, COD, and LAS from hospital wastewater. The results of this research can help to manage wastewater treatment in hospitals.
Hamid Reza Zeinaddine; Afshin Ebrahimi; Vali Alipour; Leila Rezaei
Volume 1, Issue 2 , October 2013, , Pages 89-93
Abstract
Background: This study aimed to determine the efficiency of the intermittent cycle extended aeration system (ICEAS) and the removal conditions of treating contaminants, especially nitrogen phosphorus from sea shopping center wastewater.Methods: Experiment was carried out on fish distribution center of ...
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Background: This study aimed to determine the efficiency of the intermittent cycle extended aeration system (ICEAS) and the removal conditions of treating contaminants, especially nitrogen phosphorus from sea shopping center wastewater.Methods: Experiment was carried out on fish distribution center of Bandar Abbas and 30 samples were collected in a 6 month period from the inlet of the market septic tank. The used pilot study carried out consisted of two zones: pre-react and main react zones. They were divided using a baffle wall. Firstly, wastewater enters a pre-react zone and then through the opening at the bottom of the baffle wall it enters the main react zone. The experiment was carried out with three simultaneous cycles per day.Results: The results showed that the mean of BOD5, COD, phosphorus, and nitrate and nitrite removal was 91.5, 86.7, 59.5, 49, and 80.8 percent, respectively.Conclusion: It was shown that the system is able to remove nitrogen and phosphorus almost similar to other proprietary phosphorus removal processes and with lower cost; however, it is not a proprietary process.