Utilizing multi-criteria decision analysis as an alternative to traditional screening processes f... more Utilizing multi-criteria decision analysis as an alternative to traditional screening processes for GIS modeling for landfill site selection (LSS) has attracted significant interest in recent years because of its time and cost savings and its ability to achieve better validation and accuracy. This paper surveys the developments in the modeling of LSS using geographic information systems (GIS) on the basis of multi-criteria decision analysis (MCDA) in the past two decades from 1997 to 2014. Emphasis is placed on the third and fifth stages of the overall applied methodology (selection of weights and decision rules), as well as on the efficiency of the LSS models. From the review, the strengths and limitations of using MCDA for LSS modeling via GIS are identified. Moreover, artificial neural networks instead of MCDA can be used as a new approach in the third and fifth stages of LSS models to enhance validation and accuracy.
Polish Journal of Environmental Studies, Nov 7, 2017
Landfills are one of the main soil and groundwater pollution sources in Gaza Strip/Palestine. By ... more Landfills are one of the main soil and groundwater pollution sources in Gaza Strip/Palestine. By addressing Deir Al Balah landfill, this study aims to quantify the generated and percolated leachate quantities through the landfill's lining system toward the groundwater aquifer. Leachate volumes have been quantified using two different approaches, namely the hydraulic evaluation of landfill performance (HELP) model and the water balance method (WBM), and then compared with the measured quantities by the landfill's management. Results of the HELP model showed that the average annual generated leachate volumes were 8,087 m 3 from 1997 to 2014, while the average annual percolated leachate volumes were 717 m 3 , which represented 8.9% of the generated leachate amounts. However, WBM results for the average annual leachate during the same period were 7,568 m 3. The landfill's leachate was mainly originated from the moisture content of the dumped wastes, whereas the rest came from the infiltration of the rainfall and re-circulated leachate. The cumulative modelled leachate amounts by HELP model and WBM were close, and with a difference percentage of 6.6%. However, both methods' results were higher than the measured leachate amounts. In conclusion, suitable mitigation measures are required to minimise the potential threats on to groundwater due to leachate percolation.
Environmental progress & sustainable energy, Oct 1, 2013
Activated carbon with high surface area was prepared from olive stone by microwave heating (MHOS)... more Activated carbon with high surface area was prepared from olive stone by microwave heating (MHOS) for the removal of a group of heavy metals Fe 21 , Pb 21 , and Cu 21 from synthetic wastewater. As a comparison, activated carbon was also prepared by conventional heating (CHOS) method. The effects of different reaction parameters, such as adsorbent dosage, contact time, stirring speed, and initial pH, on pollutant removal efficiency were determined. The microwave heating requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality, with higher yield. The BET surface area of carbon using microwave heating is noticeably higher than the conventional heating. Although the mesopore surface area of carbon is not vary significantly, the activation time and power consumption are considerably lower than the conventional heating rendering that the activation process via microwave is more economical than that via conventional heating. The adsorption capacity was found higher using microwave heating as compared with conventional heating. The adsorption equilibrium data were best represented by the Langmuir model and the adsorption capacity for Fe 21 , Pb 21 and Cu 21 were found to be 62.50, 23.47, and 22.73 mg=g for MHOS; while 57.47, 22.37, and 17.83 mg=g for CHOS, respectively at pH 5, 3 h contact time and 200 rpm shaking speed. Regeneration studies showed that MHOS and CHOS could be used several times by desorption with an HCl reagent. A pseudo second-order model sufficiently described the adsorption kinetics for both carbons, which indicates that the adsorption process was controlled by chemisorption. Both carbons can be used for the efficient removal of Fe 21 , Pb 21 , and Cu 21 (>99%) from contaminated wastewater. V
The adsorption of heavy metals Fe 2+ , Pb 2+ , and Cu 2+ onto olive stone activated carbon (OSAC)... more The adsorption of heavy metals Fe 2+ , Pb 2+ , and Cu 2+ onto olive stone activated carbon (OSAC) was investigated in this study. The effects of different reaction parameters (i.e. adsorbent dosage, contact time, shaking speed, and initial pH) on the pollutant removal efficiency were determined. The adsorption processes of Fe 2+ , Pb 2+ , and Cu 2+ were effectively explained using Langmuir and Freundlich isotherms. OSAC efficiently removed 99.39% Fe 2+ , 99.32% Pb 2+ , and 99.24% Cu 2+ at pH 5 and with 200 rpm shaking speed. The adsorption equilibrium data were best represented by the Langmuir model, and the monolayer adsorption capacities were found to be 57.47, 22.37, and 17.83 mg/g for Fe 2+ , Pb 2+ , and Cu 2+ , respectively. A pseudo-second-order model sufficiently described the adsorption kinetics, which indicated that the adsorption process was controlled by chemisorption. The results revealed that OSAC can be used as a low-cost adsorbent for the treatment of wastewaters contaminated by heavy metals.
Journal of Chemical Technology & Biotechnology, Apr 23, 2013
Production of activated carbon (AC) from agricultural byproducts is a research field that has gai... more Production of activated carbon (AC) from agricultural byproducts is a research field that has gained increased interest in recent years because of its potential for the disposal of agroresidues. At the same time, a beneficial byproduct that can be used in a number of environmental applications is produced. This paper surveys the developments in the production processes of AC from agricultural byproducts in the past seven years from 2005 to 2012 via conventional and microwave heating. Emphasis is placed on the applied methodology and the influences of activating conditions, such as carbonization temperature, retention time, and impregnation ratio. From the review of AC production processes, agricultural wastes produced via chemical method with microwave heating can be a source of AC with relatively higher surface area compared with that produced via conventional heating.
Journal of Engineering Research and Technology, Feb 15, 2016
Leachate pollution is one of the main problems in landfilling. Among the most problematic paramet... more Leachate pollution is one of the main problems in landfilling. Among the most problematic parameters in stabilized leachate are COD, ammonia, and color. The treatment technology that can be used may differ based on the type of leachate produced. Even after treatment, the effluent characteristics are always hard to comply with the discharge standard. Ozonation is one of the chemical processes that can be used in the treatment of landfill leachate. However, its performance when use alone is low; its effectiveness can be improved using advanced oxidants. To date, application of Fenton and persulfate reagents separately to improve ozonation process in one ozone reactor was not well established. The study aimed to evaluate and compare the performance of the three treatment processes, namely ozone, ozone/Fenton and ozone/persulfate in treating stabilized leachate separately at different experimental conditions. The performance of the three methods in the treating stabilized leachate was compared. According to the results, the performance of ozone alone was poor, and utilizing new advanced oxidation material during ozonation of such leachate was required to improve leachate treatability. Ozone/Fenton process is a viable choice for degrading and decolourizing stabilized leachate. Furthermore, ozone/persulfate process has higher performance in ammonia removal as well as it has good removal efficiency of COD and color from stabilized leachate. Suitable data for establishing fully stabilized leachate treatment plant using ozone/Fenton and ozone/persulfate was suggested. The final effluent of ozone/Fenton process complied with the discharge standard for COD and colour.
Landfills are one of the main point sources of groundwater pollution. This research mainly aims t... more Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate [Formula: see text] transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average [Formula: see text] concentration in the wells was 54 mg/L, slightly higher than the World Health Organization ([Formula: see text] 50 mg/L) standards. SESOIL model was used to predict the [Formula: see text] concentration at the bottom of the unsaturated zone. Results indicated that the current mean [Formula: see text] concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO3 will increased up to 325 mg/L within 30 years. Accordingly, the [Formula: see text] concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the [Formula: see text] level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to [Formula: see text] leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area.
Journal of Dispersion Science and Technology, May 22, 2014
ABSTRACT The removal efficiencies of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ from aqueous solution... more ABSTRACT The removal efficiencies of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ from aqueous solution with olive stone activated carbon (OSAC) were investigated in this paper. Central composite design method was used to optimize the preparation of OSAC by chemical activation using potassium hydroxide (KOH) as chemical agent. The optimum conditions obtained were 715°C activation temperature, 2 hours activation time, and 1.53 impregnation ratio. This resulted in removal of 99.25% Cu2+, 94.98% Cd2+, 99.08% Ni2+, 99.33% Pb2+, 99.41% Fe2+, and 99.17% Zn2+, as well as 73.94% OSAC yield. The surface characteristics of the activated carbon (AC) prepared under optimized condition were examined by pore structure analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The Brunauer–Emmett–Teller (BET) surface area, total pore volume, and average pore diameter of the prepared activated carbon were 886.72 m2/g, 0.507 cm3/g, and 4.22 nm, respectively. The equilibrium data of the adsorption was well fitted to the Langmuir and the highest value of adsorption capacity (Q) on the OSAC was found for Fe2+ (57.47 mg/g), followed by Pb2+ (22.37 mg/g), Cu2+ (17.83 mg/g), Zn2+ (11.14 mg/g), Ni2+ (8.42 mg/g), and Cd2+ (7.80 mg/g). The prepared OSAC can be used for efficient removal of metals from contaminated wastewater.
Usually, a few preliminary stages have been done for raw materials before the actual production o... more Usually, a few preliminary stages have been done for raw materials before the actual production of activated carbon such as materials crushing, milling and sieving to an appropriate particle size. Particle size is important for the subsequent handling of the raw material, such as mixing with a catalyst or impregnation, but it can also affect the properties of the subsequent activated carbon. This research was assessed the effect of different olive stone particle size on activated carbon production by KOH using the yield and surface area response. Three particle size ranges were examined, namely 1-2mm, 2-4.75 and the raw material in its original form. The results demonstrated that the most suitable form was 2mm to 4.75mm which resulted in 38.67% of yield and 886.72 m2 g-1 of a surface area and it has more rigidity compared with finer particle size and has more surface area and yield compared with olive stone in its original form.
Abstract The robustness of groundwater vulnerability assessment using the conventional DRASTIC is... more Abstract The robustness of groundwater vulnerability assessment using the conventional DRASTIC is highly dependent on the quality of the input data. The current study investigates the vulnerability of the western part of the coastal aquifer of the Gaza Strip, part of the Palestinian Territories, towards the southern-western part of Gaza coastal aquifer. The study utilizes the application of SWAT model to estimate the recharge factor in DRASTIC framework and investigates its impact on the vulnerability assessment compared with the No SWAT case. Not only a higher recharge resolution map was generated by using the SWAT model, but it has also improved the vulnerability index by 52% due to the incorporation of the local zonal-operation vulnerability concept. While the conventional DRASTIC framework (No SWAT) resulted in 74% of the study area of either extreme high or extreme low vulnerability classes, SWAT model was able to smoothen the vulnerability identification accounting for the slight gradual vulnerability variation across the study area with more precise vulnerability assessment. The vulnerability results were validated using real field nitrate measurements (NO3-) in water samples from water wells in the entire study area. The vulnerability assessment using the SWAT tool was in good agreement with the nitrate levels in the area compared with the conventional DRASTIC where the residual error was encountered in the case of SWAT application was less than the conventional DRASTIC 20% and 77%, respectively. The DRASTIC framework was validated using receiver operator classification (ROC) and area under curve (AUC) indicating the betterment of SWAT model application. The current study is sought to support the decision-making process and water managers to better manage the proposed aquifer recharge scheme in the area as well as to better manage the limited water resources.
Journal of environmental chemical engineering, Sep 1, 2013
ABSTRACT Contamination of natural aquatic ecosystems by wastewater containing heavy metals is a m... more ABSTRACT Contamination of natural aquatic ecosystems by wastewater containing heavy metals is a major environmental and human health issue. The removal of heavy metals using adsorption techniques with microwave-irradiated low-cost adsorbents has a few numbers of studies. In this study, the removal efficiency for cadmium (Cd2+) from aqueous solution using olive stone activated carbon (OSAC) prepared by microwave was investigated. Central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the interaction and relationship between operating variables (i.e., radiation power, radiation time, and impregnation ratio), and to develop the optimum operating condition. Equilibrium isotherms in this study were analyzed using the Langmuir and Freundlich. Kinetic data were obtained and analyzed using pseudo-first-order and pseudo-second-order equations. Based on statistical analysis, Cd2+ removal model proved to be significant with very low probability values (<0.0001). The surface characteristics of the AC prepared under optimized condition were examined by scanning electron microscopy and Fourier transform infrared spectroscopy. The optimum conditions obtained were 565 W radiation power, 7 min radiation time, and 1.87 impregnation ratio. This resulted in 95.32% removal of Cd2+ and 85.15% of OSAC yield. The process via microwave requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality. The prediction results fitted well with experimental findings. The adsorption isotherm data fitted the Langmuir isotherm well, and the monolayer adsorption capacity was found to be 11.72 mg/g. Microwaved olive stone can be used for the efficient removal of Cd2+ from contaminated wastewater.
The production of activated carbon (AC) from agricultural by-products is a research field of incr... more The production of activated carbon (AC) from agricultural by-products is a research field of increasing interest as it deals with the problem of the disposal of agro-residues, at the same time producing an added-value product that can be used in a number of environmental applications. This paper highlights an overview of the latest developments of AC production processes from agricultural byproducts, with emphasis on the applied methodology, the influences of activating conditions such as carbonization temperature, retention time, and impregnation ratio for the selected precursors. Based on reviewing AC production processes, it could be concluded that agricultural wastes produced by chemical method can be a source for AC with higher surface areas than physical method.
Utilizing multi-criteria decision analysis as an alternative to traditional screening processes f... more Utilizing multi-criteria decision analysis as an alternative to traditional screening processes for GIS modeling for landfill site selection (LSS) has attracted significant interest in recent years because of its time and cost savings and its ability to achieve better validation and accuracy. This paper surveys the developments in the modeling of LSS using geographic information systems (GIS) on the basis of multi-criteria decision analysis (MCDA) in the past two decades from 1997 to 2014. Emphasis is placed on the third and fifth stages of the overall applied methodology (selection of weights and decision rules), as well as on the efficiency of the LSS models. From the review, the strengths and limitations of using MCDA for LSS modeling via GIS are identified. Moreover, artificial neural networks instead of MCDA can be used as a new approach in the third and fifth stages of LSS models to enhance validation and accuracy.
Polish Journal of Environmental Studies, Nov 7, 2017
Landfills are one of the main soil and groundwater pollution sources in Gaza Strip/Palestine. By ... more Landfills are one of the main soil and groundwater pollution sources in Gaza Strip/Palestine. By addressing Deir Al Balah landfill, this study aims to quantify the generated and percolated leachate quantities through the landfill's lining system toward the groundwater aquifer. Leachate volumes have been quantified using two different approaches, namely the hydraulic evaluation of landfill performance (HELP) model and the water balance method (WBM), and then compared with the measured quantities by the landfill's management. Results of the HELP model showed that the average annual generated leachate volumes were 8,087 m 3 from 1997 to 2014, while the average annual percolated leachate volumes were 717 m 3 , which represented 8.9% of the generated leachate amounts. However, WBM results for the average annual leachate during the same period were 7,568 m 3. The landfill's leachate was mainly originated from the moisture content of the dumped wastes, whereas the rest came from the infiltration of the rainfall and re-circulated leachate. The cumulative modelled leachate amounts by HELP model and WBM were close, and with a difference percentage of 6.6%. However, both methods' results were higher than the measured leachate amounts. In conclusion, suitable mitigation measures are required to minimise the potential threats on to groundwater due to leachate percolation.
Environmental progress & sustainable energy, Oct 1, 2013
Activated carbon with high surface area was prepared from olive stone by microwave heating (MHOS)... more Activated carbon with high surface area was prepared from olive stone by microwave heating (MHOS) for the removal of a group of heavy metals Fe 21 , Pb 21 , and Cu 21 from synthetic wastewater. As a comparison, activated carbon was also prepared by conventional heating (CHOS) method. The effects of different reaction parameters, such as adsorbent dosage, contact time, stirring speed, and initial pH, on pollutant removal efficiency were determined. The microwave heating requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality, with higher yield. The BET surface area of carbon using microwave heating is noticeably higher than the conventional heating. Although the mesopore surface area of carbon is not vary significantly, the activation time and power consumption are considerably lower than the conventional heating rendering that the activation process via microwave is more economical than that via conventional heating. The adsorption capacity was found higher using microwave heating as compared with conventional heating. The adsorption equilibrium data were best represented by the Langmuir model and the adsorption capacity for Fe 21 , Pb 21 and Cu 21 were found to be 62.50, 23.47, and 22.73 mg=g for MHOS; while 57.47, 22.37, and 17.83 mg=g for CHOS, respectively at pH 5, 3 h contact time and 200 rpm shaking speed. Regeneration studies showed that MHOS and CHOS could be used several times by desorption with an HCl reagent. A pseudo second-order model sufficiently described the adsorption kinetics for both carbons, which indicates that the adsorption process was controlled by chemisorption. Both carbons can be used for the efficient removal of Fe 21 , Pb 21 , and Cu 21 (>99%) from contaminated wastewater. V
The adsorption of heavy metals Fe 2+ , Pb 2+ , and Cu 2+ onto olive stone activated carbon (OSAC)... more The adsorption of heavy metals Fe 2+ , Pb 2+ , and Cu 2+ onto olive stone activated carbon (OSAC) was investigated in this study. The effects of different reaction parameters (i.e. adsorbent dosage, contact time, shaking speed, and initial pH) on the pollutant removal efficiency were determined. The adsorption processes of Fe 2+ , Pb 2+ , and Cu 2+ were effectively explained using Langmuir and Freundlich isotherms. OSAC efficiently removed 99.39% Fe 2+ , 99.32% Pb 2+ , and 99.24% Cu 2+ at pH 5 and with 200 rpm shaking speed. The adsorption equilibrium data were best represented by the Langmuir model, and the monolayer adsorption capacities were found to be 57.47, 22.37, and 17.83 mg/g for Fe 2+ , Pb 2+ , and Cu 2+ , respectively. A pseudo-second-order model sufficiently described the adsorption kinetics, which indicated that the adsorption process was controlled by chemisorption. The results revealed that OSAC can be used as a low-cost adsorbent for the treatment of wastewaters contaminated by heavy metals.
Journal of Chemical Technology & Biotechnology, Apr 23, 2013
Production of activated carbon (AC) from agricultural byproducts is a research field that has gai... more Production of activated carbon (AC) from agricultural byproducts is a research field that has gained increased interest in recent years because of its potential for the disposal of agroresidues. At the same time, a beneficial byproduct that can be used in a number of environmental applications is produced. This paper surveys the developments in the production processes of AC from agricultural byproducts in the past seven years from 2005 to 2012 via conventional and microwave heating. Emphasis is placed on the applied methodology and the influences of activating conditions, such as carbonization temperature, retention time, and impregnation ratio. From the review of AC production processes, agricultural wastes produced via chemical method with microwave heating can be a source of AC with relatively higher surface area compared with that produced via conventional heating.
Journal of Engineering Research and Technology, Feb 15, 2016
Leachate pollution is one of the main problems in landfilling. Among the most problematic paramet... more Leachate pollution is one of the main problems in landfilling. Among the most problematic parameters in stabilized leachate are COD, ammonia, and color. The treatment technology that can be used may differ based on the type of leachate produced. Even after treatment, the effluent characteristics are always hard to comply with the discharge standard. Ozonation is one of the chemical processes that can be used in the treatment of landfill leachate. However, its performance when use alone is low; its effectiveness can be improved using advanced oxidants. To date, application of Fenton and persulfate reagents separately to improve ozonation process in one ozone reactor was not well established. The study aimed to evaluate and compare the performance of the three treatment processes, namely ozone, ozone/Fenton and ozone/persulfate in treating stabilized leachate separately at different experimental conditions. The performance of the three methods in the treating stabilized leachate was compared. According to the results, the performance of ozone alone was poor, and utilizing new advanced oxidation material during ozonation of such leachate was required to improve leachate treatability. Ozone/Fenton process is a viable choice for degrading and decolourizing stabilized leachate. Furthermore, ozone/persulfate process has higher performance in ammonia removal as well as it has good removal efficiency of COD and color from stabilized leachate. Suitable data for establishing fully stabilized leachate treatment plant using ozone/Fenton and ozone/persulfate was suggested. The final effluent of ozone/Fenton process complied with the discharge standard for COD and colour.
Landfills are one of the main point sources of groundwater pollution. This research mainly aims t... more Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate [Formula: see text] transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average [Formula: see text] concentration in the wells was 54 mg/L, slightly higher than the World Health Organization ([Formula: see text] 50 mg/L) standards. SESOIL model was used to predict the [Formula: see text] concentration at the bottom of the unsaturated zone. Results indicated that the current mean [Formula: see text] concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO3 will increased up to 325 mg/L within 30 years. Accordingly, the [Formula: see text] concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the [Formula: see text] level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to [Formula: see text] leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area.
Journal of Dispersion Science and Technology, May 22, 2014
ABSTRACT The removal efficiencies of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ from aqueous solution... more ABSTRACT The removal efficiencies of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ from aqueous solution with olive stone activated carbon (OSAC) were investigated in this paper. Central composite design method was used to optimize the preparation of OSAC by chemical activation using potassium hydroxide (KOH) as chemical agent. The optimum conditions obtained were 715°C activation temperature, 2 hours activation time, and 1.53 impregnation ratio. This resulted in removal of 99.25% Cu2+, 94.98% Cd2+, 99.08% Ni2+, 99.33% Pb2+, 99.41% Fe2+, and 99.17% Zn2+, as well as 73.94% OSAC yield. The surface characteristics of the activated carbon (AC) prepared under optimized condition were examined by pore structure analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The Brunauer–Emmett–Teller (BET) surface area, total pore volume, and average pore diameter of the prepared activated carbon were 886.72 m2/g, 0.507 cm3/g, and 4.22 nm, respectively. The equilibrium data of the adsorption was well fitted to the Langmuir and the highest value of adsorption capacity (Q) on the OSAC was found for Fe2+ (57.47 mg/g), followed by Pb2+ (22.37 mg/g), Cu2+ (17.83 mg/g), Zn2+ (11.14 mg/g), Ni2+ (8.42 mg/g), and Cd2+ (7.80 mg/g). The prepared OSAC can be used for efficient removal of metals from contaminated wastewater.
Usually, a few preliminary stages have been done for raw materials before the actual production o... more Usually, a few preliminary stages have been done for raw materials before the actual production of activated carbon such as materials crushing, milling and sieving to an appropriate particle size. Particle size is important for the subsequent handling of the raw material, such as mixing with a catalyst or impregnation, but it can also affect the properties of the subsequent activated carbon. This research was assessed the effect of different olive stone particle size on activated carbon production by KOH using the yield and surface area response. Three particle size ranges were examined, namely 1-2mm, 2-4.75 and the raw material in its original form. The results demonstrated that the most suitable form was 2mm to 4.75mm which resulted in 38.67% of yield and 886.72 m2 g-1 of a surface area and it has more rigidity compared with finer particle size and has more surface area and yield compared with olive stone in its original form.
Abstract The robustness of groundwater vulnerability assessment using the conventional DRASTIC is... more Abstract The robustness of groundwater vulnerability assessment using the conventional DRASTIC is highly dependent on the quality of the input data. The current study investigates the vulnerability of the western part of the coastal aquifer of the Gaza Strip, part of the Palestinian Territories, towards the southern-western part of Gaza coastal aquifer. The study utilizes the application of SWAT model to estimate the recharge factor in DRASTIC framework and investigates its impact on the vulnerability assessment compared with the No SWAT case. Not only a higher recharge resolution map was generated by using the SWAT model, but it has also improved the vulnerability index by 52% due to the incorporation of the local zonal-operation vulnerability concept. While the conventional DRASTIC framework (No SWAT) resulted in 74% of the study area of either extreme high or extreme low vulnerability classes, SWAT model was able to smoothen the vulnerability identification accounting for the slight gradual vulnerability variation across the study area with more precise vulnerability assessment. The vulnerability results were validated using real field nitrate measurements (NO3-) in water samples from water wells in the entire study area. The vulnerability assessment using the SWAT tool was in good agreement with the nitrate levels in the area compared with the conventional DRASTIC where the residual error was encountered in the case of SWAT application was less than the conventional DRASTIC 20% and 77%, respectively. The DRASTIC framework was validated using receiver operator classification (ROC) and area under curve (AUC) indicating the betterment of SWAT model application. The current study is sought to support the decision-making process and water managers to better manage the proposed aquifer recharge scheme in the area as well as to better manage the limited water resources.
Journal of environmental chemical engineering, Sep 1, 2013
ABSTRACT Contamination of natural aquatic ecosystems by wastewater containing heavy metals is a m... more ABSTRACT Contamination of natural aquatic ecosystems by wastewater containing heavy metals is a major environmental and human health issue. The removal of heavy metals using adsorption techniques with microwave-irradiated low-cost adsorbents has a few numbers of studies. In this study, the removal efficiency for cadmium (Cd2+) from aqueous solution using olive stone activated carbon (OSAC) prepared by microwave was investigated. Central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the interaction and relationship between operating variables (i.e., radiation power, radiation time, and impregnation ratio), and to develop the optimum operating condition. Equilibrium isotherms in this study were analyzed using the Langmuir and Freundlich. Kinetic data were obtained and analyzed using pseudo-first-order and pseudo-second-order equations. Based on statistical analysis, Cd2+ removal model proved to be significant with very low probability values (<0.0001). The surface characteristics of the AC prepared under optimized condition were examined by scanning electron microscopy and Fourier transform infrared spectroscopy. The optimum conditions obtained were 565 W radiation power, 7 min radiation time, and 1.87 impregnation ratio. This resulted in 95.32% removal of Cd2+ and 85.15% of OSAC yield. The process via microwave requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality. The prediction results fitted well with experimental findings. The adsorption isotherm data fitted the Langmuir isotherm well, and the monolayer adsorption capacity was found to be 11.72 mg/g. Microwaved olive stone can be used for the efficient removal of Cd2+ from contaminated wastewater.
The production of activated carbon (AC) from agricultural by-products is a research field of incr... more The production of activated carbon (AC) from agricultural by-products is a research field of increasing interest as it deals with the problem of the disposal of agro-residues, at the same time producing an added-value product that can be used in a number of environmental applications. This paper highlights an overview of the latest developments of AC production processes from agricultural byproducts, with emphasis on the applied methodology, the influences of activating conditions such as carbonization temperature, retention time, and impregnation ratio for the selected precursors. Based on reviewing AC production processes, it could be concluded that agricultural wastes produced by chemical method can be a source for AC with higher surface areas than physical method.
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Papers by Tamer Alslaibi