The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Thomas M Missimer - One of the best experts on this subject based on the ideXlab platform.
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environmental issues in seawater reverse osmosis desalination Intakes and outfalls
Desalination, 2017Co-Authors: Thomas M Missimer, Robert G MalivaAbstract:Abstract Seawater reverse osmosis (SWRO) desalination has some environmental impacts associated with the construction and operation of Intake Systems and the disposal of concentrate. The primary impact of conventional open-ocean Intake Systems is the impingement and entrainment of marine organisms. These impacts can be minimized by locating the Intake in a geographic position where oceanic productivity is low. Velocity-cap Intakes tend to reduce impacts by minimizing the number of fish entrained and some new traveling screens can allow the survival of some marine organisms. Mitigation, such as environmental restoration of habitat or restocking, can provide an acceptable solution to impacts where they are significant. Subsurface Intake Systems avoid impingement and entrainment impacts, but can cause other, less important impacts (e.g., visual, beach access). Concentrate disposal can locally impact benthic communities, if poorly diluted discharge is allowed to flow across the marine bottom. Impacts to benthic communities from concentrate discharges can be minimized by using properly-designed diffuser Systems, designed and located based current and flow modeling. The experiences of SWRO desalination to date indicate that environmental impacts can be satisfactorily minimized with proper design based on a reasonably complete environmental impact analysis prior to facility siting and design.
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subsurface Intake Systems green choice for improving feed water quality at swro desalination plants jeddah saudi arabia
Water Research, 2016Co-Authors: Abdullah H A Dehwah, Thomas M MissimerAbstract:An investigation of three seawater reverse osmosis facilities located along the shoreline of the Red Sea of Saudi Arabia that use well Intake Systems showed that the pumping-induced flow of raw seawater through a coastal aquifer significantly improves feed water quality. A comparison between the surface seawater and the discharge from the wells shows that turbidity, algae, bacteria, total organic carbon, most fractions of natural organic matter (NOM), and particulate and colloidal transparent exopolymer particles (TEP) have significant reductions in concentration. Nearly all of the algae, up to 99% of the bacteria, between 84 and 100% of the biopolymer fraction of NOM, and a high percentage of the TEP were removed during transport. The data suggest that the flowpath length and hydraulic retention time in the aquifer play the most important roles in removal of the organic matter. Since the collective concentrations of bacteria, biopolymers, and TEP in the Intake seawater play important roles in the biofouling of SWRO membranes, the observed reductions suggest that the desalination facilities that use well Intakes Systems will have a potentially lower fouling rate compared to open-ocean Intake Systems. Furthermore, well Intake system Intakes also reduce the need for chemical usage during complex pretreatment Systems required for operation of SWRO facilities using open-ocean Intakes and reduce environmental impacts.
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impact of well Intake Systems on bacterial algae and organic carbon reduction in swro desalination Systems sawaco jeddah saudi arabia
Desalination and Water Treatment, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Nizar Kammourie, Thomas M MissimerAbstract:AbstractThe Intake system can play a significant role in improving the feed water quality and ultimately influence the performance of downstream components of the seawater reverse osmosis desalination processes. In most cases, open-ocean Intakes produce poor feed water quality in terms of the abundance of naturally occurring organic matter, which increases the risk of membrane fouling. An alternative Intake is the subsurface system, which is based on the riverbank filtration concept that provides natural filtration and biological treatment of the feed water prior to the entry of the water into the desalination plant. The use of subsurface Intakes normally improves the raw water quality by reducing suspended solids, algae, bacterial, and dissolved organic carbon concentrations. Therefore, the risk of biofouling caused by these substances can be reduced by implementing the appropriate type of Intake system. The use of well Intake Systems was investigated along the Red Sea shoreline of Saudi Arabia in the Je...
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changes in feedwater organic matter concentrations based on Intake type and pretreatment processes at swro facilities red sea saudi arabia
Desalination, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Harvey Winters, Thomas M MissimerAbstract:Abstract Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) Systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface Intake Systems or placement of the Intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well Intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An Intake placed at a depth of 9 m below the surface was found to have limited impact on improving water quality compared to a surface Intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.
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feasibility and design of seabed gallery Intake Systems along the arabian gulf coast of saudi arabia with a discussion on gallery Intake use for the entire arabian gulf region
2015Co-Authors: Rinaldi Rachman, Thomas M MissimerAbstract:The Arabian Gulf coast of Saudi Arabia contains a large number of existing desalination facilities of which many use the seawater reverse (SWRO) osmosis process. Many SWRO facilities have had historical operational problems with membrane biofouling. Subsurface Intake system feasibility was assessed generally for the coastline of Saudi Arabia and a site-specific investigation was conducted at Ras Abu Ali Island. It was found that the common occurrence of sabkhas along the shoreline of Saudi Arabia causes the use of conventional vertical wells to be risky due to migration of hypersaline water into them. All well types do not appear to be feasible based on the shoreline and nearshore geological conditions. Beach galleries were assessed and are also subject to failure caused by migration of hypersaline water and possible burial by dune sands moving eastward from the desert into the Arabian Gulf. Seabed gallery Intake Systems were found to be the most technically feasible subsurface Intake type which could provide high capacity SWRO facilities with feed water. However, the low slope from the beach seaward and the tide range necessitate that seabed galleries would have to be constructed over 500 m seaward of the beach. This distance would make the construction complex and would require future design and construction innovations. Perhaps the seabed gallery cells could be constructed adjacent to an artificial fill peninsula that would allow easier access and less expensive construction.
Abdullah H A Dehwah - One of the best experts on this subject based on the ideXlab platform.
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subsurface Intake Systems green choice for improving feed water quality at swro desalination plants jeddah saudi arabia
Water Research, 2016Co-Authors: Abdullah H A Dehwah, Thomas M MissimerAbstract:An investigation of three seawater reverse osmosis facilities located along the shoreline of the Red Sea of Saudi Arabia that use well Intake Systems showed that the pumping-induced flow of raw seawater through a coastal aquifer significantly improves feed water quality. A comparison between the surface seawater and the discharge from the wells shows that turbidity, algae, bacteria, total organic carbon, most fractions of natural organic matter (NOM), and particulate and colloidal transparent exopolymer particles (TEP) have significant reductions in concentration. Nearly all of the algae, up to 99% of the bacteria, between 84 and 100% of the biopolymer fraction of NOM, and a high percentage of the TEP were removed during transport. The data suggest that the flowpath length and hydraulic retention time in the aquifer play the most important roles in removal of the organic matter. Since the collective concentrations of bacteria, biopolymers, and TEP in the Intake seawater play important roles in the biofouling of SWRO membranes, the observed reductions suggest that the desalination facilities that use well Intakes Systems will have a potentially lower fouling rate compared to open-ocean Intake Systems. Furthermore, well Intake system Intakes also reduce the need for chemical usage during complex pretreatment Systems required for operation of SWRO facilities using open-ocean Intakes and reduce environmental impacts.
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impact of well Intake Systems on bacterial algae and organic carbon reduction in swro desalination Systems sawaco jeddah saudi arabia
Desalination and Water Treatment, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Nizar Kammourie, Thomas M MissimerAbstract:AbstractThe Intake system can play a significant role in improving the feed water quality and ultimately influence the performance of downstream components of the seawater reverse osmosis desalination processes. In most cases, open-ocean Intakes produce poor feed water quality in terms of the abundance of naturally occurring organic matter, which increases the risk of membrane fouling. An alternative Intake is the subsurface system, which is based on the riverbank filtration concept that provides natural filtration and biological treatment of the feed water prior to the entry of the water into the desalination plant. The use of subsurface Intakes normally improves the raw water quality by reducing suspended solids, algae, bacterial, and dissolved organic carbon concentrations. Therefore, the risk of biofouling caused by these substances can be reduced by implementing the appropriate type of Intake system. The use of well Intake Systems was investigated along the Red Sea shoreline of Saudi Arabia in the Je...
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changes in feedwater organic matter concentrations based on Intake type and pretreatment processes at swro facilities red sea saudi arabia
Desalination, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Harvey Winters, Thomas M MissimerAbstract:Abstract Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) Systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface Intake Systems or placement of the Intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well Intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An Intake placed at a depth of 9 m below the surface was found to have limited impact on improving water quality compared to a surface Intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.
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subsurface Intakes for seawater reverse osmosis facilities capacity limitation water quality improvement and economics
Desalination, 2013Co-Authors: Thomas M Missimer, Noreddine Ghaffour, Abdullah H A Dehwah, Rinaldi RachmanAbstract:Abstract The use of subsurface Intake Systems for seawater reverse osmosis (SWRO) desalination plants significantly improves raw water quality, reduces chemical usage and environmental impacts, decreases the carbon footprint, and reduces cost of treated water to consumers. These Intakes include wells (vertical, angle, and radial type) and galleries, which can be located either on the beach or in the seabed. Subsurface Intakes act both as Intakes and as part of the pretreatment system by providing filtration and active biological treatment of the raw seawater. Recent investigations of the improvement in water quality made by subsurface Intakes show lowering of the silt density index by 75 to 90%, removal of nearly all algae, removal of over 90% of bacteria, reduction in the concentrations of TOC and DOC, and virtual elimination of biopolymers and polysaccharides that cause organic biofouling of membranes. Economic analyses show that overall SWRO operating costs can be reduced by 5 to 30% by using subsurface Intake Systems. Although capital costs can be slightly to significantly higher compared to open-ocean Intake system costs, a preliminary life-cycle cost analysis shows significant cost saving over operating periods of 10 to 30 years.
Rinaldi Rachman - One of the best experts on this subject based on the ideXlab platform.
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feasibility and design of seabed gallery Intake Systems along the arabian gulf coast of saudi arabia with a discussion on gallery Intake use for the entire arabian gulf region
2015Co-Authors: Rinaldi Rachman, Thomas M MissimerAbstract:The Arabian Gulf coast of Saudi Arabia contains a large number of existing desalination facilities of which many use the seawater reverse (SWRO) osmosis process. Many SWRO facilities have had historical operational problems with membrane biofouling. Subsurface Intake system feasibility was assessed generally for the coastline of Saudi Arabia and a site-specific investigation was conducted at Ras Abu Ali Island. It was found that the common occurrence of sabkhas along the shoreline of Saudi Arabia causes the use of conventional vertical wells to be risky due to migration of hypersaline water into them. All well types do not appear to be feasible based on the shoreline and nearshore geological conditions. Beach galleries were assessed and are also subject to failure caused by migration of hypersaline water and possible burial by dune sands moving eastward from the desert into the Arabian Gulf. Seabed gallery Intake Systems were found to be the most technically feasible subsurface Intake type which could provide high capacity SWRO facilities with feed water. However, the low slope from the beach seaward and the tide range necessitate that seabed galleries would have to be constructed over 500 m seaward of the beach. This distance would make the construction complex and would require future design and construction innovations. Perhaps the seabed gallery cells could be constructed adjacent to an artificial fill peninsula that would allow easier access and less expensive construction.
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subsurface Intakes for seawater reverse osmosis facilities capacity limitation water quality improvement and economics
Desalination, 2013Co-Authors: Thomas M Missimer, Noreddine Ghaffour, Abdullah H A Dehwah, Rinaldi RachmanAbstract:Abstract The use of subsurface Intake Systems for seawater reverse osmosis (SWRO) desalination plants significantly improves raw water quality, reduces chemical usage and environmental impacts, decreases the carbon footprint, and reduces cost of treated water to consumers. These Intakes include wells (vertical, angle, and radial type) and galleries, which can be located either on the beach or in the seabed. Subsurface Intakes act both as Intakes and as part of the pretreatment system by providing filtration and active biological treatment of the raw seawater. Recent investigations of the improvement in water quality made by subsurface Intakes show lowering of the silt density index by 75 to 90%, removal of nearly all algae, removal of over 90% of bacteria, reduction in the concentrations of TOC and DOC, and virtual elimination of biopolymers and polysaccharides that cause organic biofouling of membranes. Economic analyses show that overall SWRO operating costs can be reduced by 5 to 30% by using subsurface Intake Systems. Although capital costs can be slightly to significantly higher compared to open-ocean Intake system costs, a preliminary life-cycle cost analysis shows significant cost saving over operating periods of 10 to 30 years.
Robert G Maliva - One of the best experts on this subject based on the ideXlab platform.
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environmental issues in seawater reverse osmosis desalination Intakes and outfalls
Desalination, 2017Co-Authors: Thomas M Missimer, Robert G MalivaAbstract:Abstract Seawater reverse osmosis (SWRO) desalination has some environmental impacts associated with the construction and operation of Intake Systems and the disposal of concentrate. The primary impact of conventional open-ocean Intake Systems is the impingement and entrainment of marine organisms. These impacts can be minimized by locating the Intake in a geographic position where oceanic productivity is low. Velocity-cap Intakes tend to reduce impacts by minimizing the number of fish entrained and some new traveling screens can allow the survival of some marine organisms. Mitigation, such as environmental restoration of habitat or restocking, can provide an acceptable solution to impacts where they are significant. Subsurface Intake Systems avoid impingement and entrainment impacts, but can cause other, less important impacts (e.g., visual, beach access). Concentrate disposal can locally impact benthic communities, if poorly diluted discharge is allowed to flow across the marine bottom. Impacts to benthic communities from concentrate discharges can be minimized by using properly-designed diffuser Systems, designed and located based current and flow modeling. The experiences of SWRO desalination to date indicate that environmental impacts can be satisfactorily minimized with proper design based on a reasonably complete environmental impact analysis prior to facility siting and design.
Samir Almashharawi - One of the best experts on this subject based on the ideXlab platform.
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impact of well Intake Systems on bacterial algae and organic carbon reduction in swro desalination Systems sawaco jeddah saudi arabia
Desalination and Water Treatment, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Nizar Kammourie, Thomas M MissimerAbstract:AbstractThe Intake system can play a significant role in improving the feed water quality and ultimately influence the performance of downstream components of the seawater reverse osmosis desalination processes. In most cases, open-ocean Intakes produce poor feed water quality in terms of the abundance of naturally occurring organic matter, which increases the risk of membrane fouling. An alternative Intake is the subsurface system, which is based on the riverbank filtration concept that provides natural filtration and biological treatment of the feed water prior to the entry of the water into the desalination plant. The use of subsurface Intakes normally improves the raw water quality by reducing suspended solids, algae, bacterial, and dissolved organic carbon concentrations. Therefore, the risk of biofouling caused by these substances can be reduced by implementing the appropriate type of Intake system. The use of well Intake Systems was investigated along the Red Sea shoreline of Saudi Arabia in the Je...
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changes in feedwater organic matter concentrations based on Intake type and pretreatment processes at swro facilities red sea saudi arabia
Desalination, 2015Co-Authors: Abdullah H A Dehwah, Samir Almashharawi, Harvey Winters, Thomas M MissimerAbstract:Abstract Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) Systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface Intake Systems or placement of the Intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well Intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An Intake placed at a depth of 9 m below the surface was found to have limited impact on improving water quality compared to a surface Intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.