Research Paper
Emeka Donald Anyanwu; Anthony Chukwubueze Okoboshi; Onyinyechi Gladys Adetunji; Florence Nneka Onyiwalu
Abstract
The levels of heavy metals in the environment have seriously increased during the last few decades due to human activities. Aquatic environment is a major recipient of heavy metal pollution. Heavy metal content of Ahi River was studied between May and October 2023 in three stations, compared with national ...
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The levels of heavy metals in the environment have seriously increased during the last few decades due to human activities. Aquatic environment is a major recipient of heavy metal pollution. Heavy metal content of Ahi River was studied between May and October 2023 in three stations, compared with national standards to determine the water’s suitability for drinking. The water samples were collected and analysed using standard methods. The eight evaluated heavy metals and concentrations were: Iron (0.93-2.83 mg/L), Zinc (0.61-0.90 mg/L), copper (0.1-0.9 mg/L), lead (0.05-0.34 mg/L), chromium (0.08-0.64 mg/L), cadmium (0.03-0.21 mg/L), nickel (0.02-0.14 mg/L) and manganese (0.38-1.1 mg/L). All the metals exceeded limits for drinking water (except zinc and copper). The lowest and highest values for most of the metals were recorded in May and September 2023, respectively. However, station 3 had relatively high values in all the metals. The heavy metal content was influenced by geology, rainfall and human activities. Single factor pollution index (SFPI) and comprehensive pollution index (CPI) showed the water was polluted and unsafe while pollution load sharing rate (PLSR) showed that lead and cadmium contributed most to the pollution. The concentrations of the metals influenced the values of the indices, therefore, waters of Ahi River is not suitable for drinking but can be used for other domestic purposes.
Research Paper
Muhammad Kashif; Muhammad Jawad; Azmat Ali Khan; Hao Sun; Khair Ullah; Olayemi Fakayode; Shohreh Azizi
Abstract
This study presents a method for enhancing the photocatalytic properties of strontium oxide (SrO) nanoparticles (NPs) through doping with Iron (Fe) and titanium (Ti) ions using hydrothermal synthesis. The materials were characterized using a range of spectroscopic and microscopic techniques to ensure ...
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This study presents a method for enhancing the photocatalytic properties of strontium oxide (SrO) nanoparticles (NPs) through doping with Iron (Fe) and titanium (Ti) ions using hydrothermal synthesis. The materials were characterized using a range of spectroscopic and microscopic techniques to ensure accurate analysis of their structure and composition. Photocatalytic efficiencies of the as-synthesized materials were evaluated against the degradation of methyl orange dye, achieving about 98 % removal in 90 min with 3 % doped material. The degradation efficiency was found to be dependent on several factors including pH, initial dye concentration, and catalyst dosage. Optimal conditions were determined to be a pH of 4, an initial dye concentration of 20 mg/L, and a catalyst dosage of 150 mg. These findings suggest that the Fe/Ti-codoped SrO nanoparticles hold significant potential for applications in environmental cleanup processes, particularly in the degradation of organic pollutants. The study provides valuable insights into the synthesis and application of doped nanoparticles in photocatalysis, highlighting their efficiency and the importance of optimizing reaction conditions to maximize performance.
Research Paper
Karabo Concelia Malakane; Thabang Maphanga
Abstract
The effluents from the South African wastewater treatment plant systems have a detrimental effect on the country's water resources and public health. Municipal wastewater services are often considered inadequate when compared to national standards and inter-national benchmarks. The objective of this ...
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The effluents from the South African wastewater treatment plant systems have a detrimental effect on the country's water resources and public health. Municipal wastewater services are often considered inadequate when compared to national standards and inter-national benchmarks. The objective of this study was to evaluate the quality of wastewater effluent discharged from multiple sewage treatment facilities throughout the Crocodile River catchment area in the Lowveld. The quality of wastewater effluent was tested at nine wastewater discharge stations along the Crocodile River. Samples were collected monthly during the eight-month duration of 2021. Samples were analyzed by the South African National Accreditation System (SANAS) laboratory and statistical analysis was conducted using the Seaborn program. The results indicated that almost all the sampling sites had very high suspended solid concentrations in their effluent discharges; the highest was recorded at Kanyamazane site with 26,20 mg/L, and the lowest at Kabokweni with 7,2 mg/L. High levels chemical oxygen demand (COD) were recorded, which increased nitrate levels. High COD is an indication of water treatment system inefficiency. In most cases, the levels of E. coli were within the legal required limits, except for Kabokweni (192425)/100 mL) and Hectorspruit (1183/100 mL). R2= 0.83 showed a strong association between suspended particles and ammonia nitrogen (NH3-N). Pollution of the Crocodile River is mostly due to wastewater treatment facility failure; therefore, the South African government should invest in wastewater treatment and sludge management technology. Funds should be utilized efficiently for infrastructure development and maintenance.
Research Paper
Farzaneh Falahi; Parviz Mohammadi; Seyyed Alireza Mousavi; Arash Arami-Niya
Abstract
Soft drinks are industrial intermediate chemicals found in wastewater and are among the most significant environmental pollutants. Up-flow anaerobic sludge blanket (UASB) reactors are used to treat soft drink wastewater, offering high-volume loading capacity, optimal grain deposition, and the ability ...
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Soft drinks are industrial intermediate chemicals found in wastewater and are among the most significant environmental pollutants. Up-flow anaerobic sludge blanket (UASB) reactors are used to treat soft drink wastewater, offering high-volume loading capacity, optimal grain deposition, and the ability to bear impact loads. The use of support materials can enhance biological productivity and expedite the UASB start-up period. In this study, bone powder was utilized as a support material in a UASB reactor to remove contaminants from wastewater. During the 70-day sludge adaptation period, the treatment reactor achieved a 93% reduction in COD, while the control reactor achieved a 65% reduction. Biogas production was higher in the bone powder UASB reactor (1750 mL/d) compared to the control UASB reactor (1100 mL/d), and the bone powder UASB reactor demonstrated greater resistance to shock loading. The improvement in sludge settling, shear strength, and higher biological activity in the bone powder UASB reactor was attributed to the formation of large granular sludge. The size of the granular sludge increased further with the colonization of filamentous bacteria at the irregular levels of bone powder.
Research Paper
Nasim Saniei; Nahid Ghasemi; Ali Akbar Zinatizadeh; Sirus Zinadini; Majid Ramezani
Abstract
Graphene oxide has attracted many interests in the recent decade due to its unique mechanical and chemical properties. This study focuses on the modification of graphene oxide and preparation proton exchange membrane (PEM) by sulfonated poly ether ether ketone (SPEEK) as base polymer for using in MFC ...
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Graphene oxide has attracted many interests in the recent decade due to its unique mechanical and chemical properties. This study focuses on the modification of graphene oxide and preparation proton exchange membrane (PEM) by sulfonated poly ether ether ketone (SPEEK) as base polymer for using in MFC as a modified membrane to remove COD and electricity generation. The scanning electron microscope (SEM) images, Fourier transform infrared (FTIR) and contact angle measurements were used to verify hydrophilic properties of the synthesized membranes. First, preparation procedures and properties of sulfonated reduced graphene oxide are briefly described. Subsequently, modification of proton exchange membrane from SPEEK polymer with prepared nano particle of sulfonated reduced graphene oxide 0.5 wt. % and its operation in MFC was considered. COD removal, power density, current density and coulombic efficiency were monitored during the process operation to evaluate the MFC performance. During the process operation, COD removal, power density, current density, and coulombic efficiency were tracked to assess the MFC performance. The power density and current density, 39.43 mW/m2 and 161 mA/m2 and the columbic efficiency 48.9 % was obtained, respectively. The COD removal of 89.5 % was obtained.
Research Paper
Reza Kheyri; Mohammad Ali Maysami; Ali Alishah
Abstract
Wastewater output has increased considerably as a result of global population growth. Efforts to manage wastewater are expanding globally. Bio-based methods are useful and effective for treating a wide range of wastewaters, especially those from homes. In this research, the gray water stream at Sari ...
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Wastewater output has increased considerably as a result of global population growth. Efforts to manage wastewater are expanding globally. Bio-based methods are useful and effective for treating a wide range of wastewaters, especially those from homes. In this research, the gray water stream at Sari Agricultural College in the north of Iran was treated using an anaerobic biological method. The purpose of this study was to determine whether using treated gray water for landscape irrigation was feasible or not. A fine screening pre-treatment system and a septic tank system were created in order to achieve this goal. After the first stage screening of superfluous solid components, anaerobic digestion was carried out for 26 hours at a temperature of between 14 and 16 °C in a 5 m3 septic tank. Treatment method function was revealed by measuring and comparing the pollutant indices with the permissible rates. The obtained data were: BOD 19.5 mg/L, COD 185 mg/L, Suspended Solid (SS) 90 mg/L, Organic Matter (OM) 80 mg/L, NO3 26 mg/L, PO4 6.25 mg/L, Oil and Grease (O&G) 9.3%, pH 5.9-7.1. The permissible rates for these indices are 100, 200, 200, 300, 30, 6.75, 10, and 6.8-7.1, respectively. The treated gray water was allowed to be utilized as irrigation water. After irrigating, the landscape did not face any negative effects. Nonetheless, the high acidity was owing to the detergents in effluent and this was the main reason provides a vast range of microelements leading to poisoning plants in a long period.
Research Paper
Zohreh Jahannia; Hassan Rezaei; Hajar Abyar; Somayeh Namroodi
Abstract
Cost-effective dye wastewater treatment approaches are critically required for the long-term sustainability of textile industries. To fill the gaps, multiple high-potential adsorbents derived from biomass have been proposed. For this purpose, this study was conducted to present an applicable and cost-effective ...
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Cost-effective dye wastewater treatment approaches are critically required for the long-term sustainability of textile industries. To fill the gaps, multiple high-potential adsorbents derived from biomass have been proposed. For this purpose, this study was conducted to present an applicable and cost-effective biochar synthesized from cow dung to remove methylene blue from the aqueous solutions. The potential of cow dung-based biochar was optimized under various pH, biochar dose, methylene blue concentration, contact time, and temperature. The maximum removal was 96% achieved at optimum conditions, 20 mg/l methylene blue concentration, 0.2 g biochar dose, pH of 6, and 90 min contact time at ambient temperature. The methylene blue adsorption process followed the Freundlich isotherm (R2=0.9827) and pseudo-second-order (R2=0.999) kinetic models, implying multilayered adsorption on the heterogenous surface and chemisorption mechanism, respectively. Furthermore, the adsorption process was spontaneous and exothermic due to negative Gibbs free energy (ΔG0) and enthalpy (ΔH0) with the reduction at randomness of methylene blue molecules and adsorbent interaction based on negative entropy (ΔS0). Regarding the high efficiency of cow dung-based biochar to adsorb methylene blue, it is recommended that further investigations consider the biochar activation and functionalization intending to upgrade its adsorption capacity.
Research Paper
Sajad Abdi; Hossein Hazrati; Seyed Majid Abdoli
Abstract
Over recent decades, there has been a documented rise in natural organic matter (NOM) levels in surface waters globally, adversely affecting drinking water treatment processes. This study is focused on employing adsorption techniques to explore the removal of proteinaceous NOM from an aqueous solution. ...
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Over recent decades, there has been a documented rise in natural organic matter (NOM) levels in surface waters globally, adversely affecting drinking water treatment processes. This study is focused on employing adsorption techniques to explore the removal of proteinaceous NOM from an aqueous solution. A chitosan/polyacrylamide (chitosan/PAM) hydrogel was synthesized through a multi-step procedure involving chitosan and acrylamide solutions preparation, polymerization initiation, mixing, gelation, purification, and drying. The Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) techniques were employed to characterize the synthesized chitosan/PAM hydrogel, examining its structural and morphological features. Adsorption experiments were conducted to assess performance of chitosan/PAM hydrogel adsorbent for the removal of bovine serum albumin (BSA) from aqueous solutions. Various physical parameters including temperature, time, pH, initial BSA concentration, and adsorbent dosage were examined in batch experiments. The adsorption capacity of chitosan/PAM hydrogel for BSA and removal percent of BSA was found 617 mg/g and 77.2 % at 6 h under optimum conditions (T= 25ºC and pH=7) with kinetic studies indicating a best fit with the pseudo-1st-order model. Isotherm studies demonstrated that the Temkin isotherm model best fitted with experimental BSA adsorption data (R2 > 0.99). The findings underscore the efficacy of the developed adsorbent in efficiently removing natural proteins. Furthermore, the experimental results indicate that the adsorption capacity of the chitosan/PAM hydrogel augmented with rising temperature and initial BSA concentration.
Research Paper
Seyed Mehdi Sajjadi
Abstract
Treatment of wastewater is a crucial step in reducing pollution from the textile and dyeing industries. One of the best techniques for dye removal is photocatalytic processes, and TiO2 is frequently employed in numerous wastewater treatment applications. In this study, different adsorption isotherm models ...
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Treatment of wastewater is a crucial step in reducing pollution from the textile and dyeing industries. One of the best techniques for dye removal is photocatalytic processes, and TiO2 is frequently employed in numerous wastewater treatment applications. In this study, different adsorption isotherm models and experimental data from the removal of the methylene blue dye from wastewater by applying GO/TiO2/SiO2 nanocomposite were compared. The correlation coefficient values (R2) for the Langmuir isotherm type 1 (Hanes-Woolf), Temkin, and Freundlich were determined to be, respectively, 0.9957, 0.9823, and 0.9515. Additionally, the R2 values for the Redlich-Peterson, Sips, and Toth isotherms models were 0.9575, 0.9626, and 0.9629, respectively. Therefore, Langmuir isotherm type 1 has the highest R2 and is the best model for surface adsorption of methylene blue on GO/TiO2/SiO2 photocatalyst. As a result, monolayer adsorption was most likely dominating during the adsorption. Furthermore, this photocatalyst proved suitable for lower methylene blue concentrations and systems with lower temperature sensitivity.
Research Paper
Hajar Esnaashari; Narges Ganjali; Ali Sardar Shahraki
Abstract
Water is one of the most basic environmental resources and plays an important role in human life. The Sistan river is the only source of water supply in this area and is completely dependent on the border river of Hirmand. The water of this river fluctuates greatly due to the interference of the country ...
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Water is one of the most basic environmental resources and plays an important role in human life. The Sistan river is the only source of water supply in this area and is completely dependent on the border river of Hirmand. The water of this river fluctuates greatly due to the interference of the country of Afghanistan, climate changes and the existence of Hamon international wetland, which has made the issue of decision-making regarding the management of water resources in Sistan region more than in other regions. This study, using the WEAP model, deals with modeling the effects of changes made in the water resources system in the Sistan region, which has special weather conditions. The results of this study showed that policies implemented in recent years have a positive effect on increasing water resources and decreasing water shortages in agriculture, drinking water, and the environment sectors, and supply-side policies combined with demand-side policies like increasing irrigation efficiency and reducing the per capita consumption of water can have a greater effect on economic, social and environmental development. It was also found that domestic water needs were met in all months, but in the agricultural sector, only 20% of agricultural water was provided to farmers in the summer months. Therefore, based on field observations, the agricultural sector is facing more problems in supplying water to the regions. Finally, for environmental needs, 184,000 cubic meters of water needed by Hamon Hirmand has not been supplied.
Research Paper
Parastoo Yavari; Ali Akbar Akhtari; Arash Azari
Abstract
In the operation of water distribution networks in cities, leakage from pipes always causes problems for human health and for the environment. Leakage openings in pipes may exist in different shapes. Circular holes are common in corroded and punched pipes. In the leakage studies, the area of these openings ...
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In the operation of water distribution networks in cities, leakage from pipes always causes problems for human health and for the environment. Leakage openings in pipes may exist in different shapes. Circular holes are common in corroded and punched pipes. In the leakage studies, the area of these openings is usually assumed to be fixed and the leakage exponent is about 0.5. In this study, an analytical equation has been presented with two purposes. First, Examining the changes in the leak area and leakage exponent of circular holes. Second, providing an equation that contains more parameters than the general leakage equations. By using such an equation, the accuracy of leakage estimation is increased due to the direct involvement of the effective parameters. Also, for the possibility of modeling different leakage equations, including the present equation, a new hydraulic analysis model has been developed. This model tries to improve leakage modeling by including more capabilities than the existing hydraulic analysis models. Results showed that the leak area in circular holes is not fixed and changes due to different parameters. Comparison of the present equation and the orifice equation showed a significant difference which confirms that the orifice equation cannot be always used for circular leaks. In the study of leakage exponent, it was found that for polyethylene pipes, the leakage exponent is higher than value of 0.5 mentioned in the other studies and it can take different values depending on the leakage position in the network. Increasing the hole diameter did not affect the leakage exponent, but increased the leakage coefficient. On the other hand, for steel pipes, the leakage coefficient was fixed and the exponent remained around 0.5. Finally, the results showed the usefulness of the developed hydraulic analysis model for implementing the scenarios defined in this study.
Research Paper
Ahmad Naeemah Bashara; Farhad Qaderi
Abstract
Due to the rapid population and economic growth, the demand for water has increased. In addition, the natural resources are limited and degrade because of several factors such as the climate change. These challenges lead to reduce the ability of providing water at the required quantity and quality. One ...
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Due to the rapid population and economic growth, the demand for water has increased. In addition, the natural resources are limited and degrade because of several factors such as the climate change. These challenges lead to reduce the ability of providing water at the required quantity and quality. One of solutions to maintain the sustainability of water supply from different sources is reuse of wastewater. For this aim, it is crucial to optimize wastewater systems. This research paper aims to describe different modelling possibilities and optimization methods for various components of integrated urban wastewater systems. The main conclusion of this research paper is the lack of study of optimum design and operation of urban wastewater systems in a holistic method. Moreover, most of previous studies on integrated wastewater management have been conducted on combined sewer systems.
