Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recen...Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recent years.The dams that supply water to most regions of Morocco have faced periods of drought.This led the government to start a large-scale seawater desalination project that shall produce over 2 MM m^(3)/year.The most common environmental impact associated with desalination plants is the high concentration brine discharge which can alter the physical,chemical,and biological properties of the receiving water body,In fact,the increasing number of desalination plants along the coastline amplifies the potential risks that brine discharges pose to marine ecosystems.This highlights the critical need for regulations to manage pollutant concentrations in water,both at the discharge point(Effluent Standards-ES)and in the receiving environment(Ambient Standards-AS).Law 36-15,in its Article 72,grants any natural or legal person,whether public or private,the right to carry out seawater desalination to meet their own water needs or those of other users,in accordance with current legislation and regulations.However,the definition of regulations concerning marine environmental aspects and the substantial limits for discharges has not yet been specified.Indeed,these regulations will need to be developed with due consideration for the local biodiversity.These regulations should also take into account the technical criteria required to determine the compliance point and define the boundaries of the brine discharge impact zone.展开更多
Modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and groundwater.This study aims to model the monthly hydrological water cycle ...Modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and groundwater.This study aims to model the monthly hydrological water cycle in the Wadi Mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological model.SWAT modelling integrates spatial data such as the Digital Elevation Model(DEM),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind speed.The SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December 2014.Sensitivity and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi Mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this basin.The SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.展开更多
Desupersaturation is a complex cooling operation that involves hydrodynamic,thermal and mechanical phenomena.This process requires continuous agitation to avoid fouling problems and sludge deposition.The current work ...Desupersaturation is a complex cooling operation that involves hydrodynamic,thermal and mechanical phenomena.This process requires continuous agitation to avoid fouling problems and sludge deposition.The current work aims to investigate the well mixedness in the desupersaturation tank for optimal performance.For this purpose,a multi-fluid CFD study was conducted based on the Euler–Euler modeling approach,considering a multiphase flow involving a liquid phase(phosphoric acid)and a poly-dispersed solid phase,i.e.a sludge with three different sizes where each size is considered as a separate phase.First,the hydrodynamic behavior of the flow within the agitated desupersaturator is analyzed through the investigation of the velocity fields as well as the power and pumping numbers,to determine both the agitator capacity to pump the flow and its power consumption during the operation.Then,in order to assess the mixture homogeneity,we evaluated the solid suspension in the desupersaturation reactor following conventional methods and two new proposed methodologies:the first approach is to evaluate the suspension quality in the mixing system by compartment and the second consists on the assessment of the uniform convergence of the solid concentration.Furthermore,we calculated the time required to achieve a full suspension at different solid concentrations.On other hand,we conducted a detailed analysis of the solid distribution dependency on the impeller rotational speed at different solid volume fraction,which allows a good understanding of the parameters controlling the homogenization in the desupersaturator.展开更多
The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship betwe...The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship between energy and vacuum! So it can be considered that the energy is a function of the vacuum ratio (v). Therefore, we can say that vacuum ratio constitutes a part of space-time. With simple mathematical formula, we can easily obtain the equation of the Energy Vacuum. This gives us the distribution of the energy Vacuum (E) into two parts are inversely proportional from our vacuum energy diagram, the effective energy that the sole responsible for Curvature of space-time fabric, and the lost energy that the responsible of the Gravitational waves [3]. From these equations, we can find that the relationship with Energy and Vacuum ratio is linear which are compatible with Quantum Mechanics laws and Maintains the energy conservation principle. It is also observed that the equations obtained through our theory are Combining relativity and Quantum Mechanics into one continuum. If we take the equations of our theory, we can easily obtain from Curvature of Space-Time Fabric, the Gravity value equation which equals to the square root of energy multiply times the square of the vacuum ratio. On other hand, a curvature matrix and a Time Dilation’s Circle are proposed, which gives us a new method to facilitate the calculations of the parameters involved in the Space-Time Curvature.展开更多
Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties.In the present study,through numerical simulations a link is established between the ther...Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties.In the present study,through numerical simulations a link is established between the thermal performance of composite materials and their microstructures.First,a two-phase 3D composite structure is modeled,then the RSA(Random Sequential Addition)algorithm and a finite element method(FE)are applied to evaluate the effective thermal conductivity of these composites in the steady-state.In particular,building composites based on gypsum and clay,consolidated with peanut shell additives and/or cork are considered.The numerically determined thermal conductivities are compared with values experimentally calculated using the typical tools of modern metrology,and with available analytical models.The calculated thermal conductivities of the clay-based materials are 0.453 and 0.301 W.m^(−1).K^(−1) with peanut shells and cork,respectively.Those of the gypsum-based materials are 0.245 and 0.165 W.m^(−1).K^(−1) with peanut shells and cork,respectively.It is shown that,in addition to its dependence on the volume fraction of inclusions,the effective thermal conductivity is also influenced by other parameters such as the shape of inclusions and their distribution.The relative deviations,on average,do not exceed 6.8%,which provides evidence for the reliability of the used approach for random heterogeneous materials.展开更多
文摘Seawater desalination has been considered an important solution for water scarcity in coastal areas.Morocco,with its 3,500 km long coastline,has seen significant growth in population and industrial activities in recent years.The dams that supply water to most regions of Morocco have faced periods of drought.This led the government to start a large-scale seawater desalination project that shall produce over 2 MM m^(3)/year.The most common environmental impact associated with desalination plants is the high concentration brine discharge which can alter the physical,chemical,and biological properties of the receiving water body,In fact,the increasing number of desalination plants along the coastline amplifies the potential risks that brine discharges pose to marine ecosystems.This highlights the critical need for regulations to manage pollutant concentrations in water,both at the discharge point(Effluent Standards-ES)and in the receiving environment(Ambient Standards-AS).Law 36-15,in its Article 72,grants any natural or legal person,whether public or private,the right to carry out seawater desalination to meet their own water needs or those of other users,in accordance with current legislation and regulations.However,the definition of regulations concerning marine environmental aspects and the substantial limits for discharges has not yet been specified.Indeed,these regulations will need to be developed with due consideration for the local biodiversity.These regulations should also take into account the technical criteria required to determine the compliance point and define the boundaries of the brine discharge impact zone.
文摘Modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and groundwater.This study aims to model the monthly hydrological water cycle in the Wadi Mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological model.SWAT modelling integrates spatial data such as the Digital Elevation Model(DEM),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind speed.The SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December 2014.Sensitivity and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi Mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this basin.The SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.
文摘Desupersaturation is a complex cooling operation that involves hydrodynamic,thermal and mechanical phenomena.This process requires continuous agitation to avoid fouling problems and sludge deposition.The current work aims to investigate the well mixedness in the desupersaturation tank for optimal performance.For this purpose,a multi-fluid CFD study was conducted based on the Euler–Euler modeling approach,considering a multiphase flow involving a liquid phase(phosphoric acid)and a poly-dispersed solid phase,i.e.a sludge with three different sizes where each size is considered as a separate phase.First,the hydrodynamic behavior of the flow within the agitated desupersaturator is analyzed through the investigation of the velocity fields as well as the power and pumping numbers,to determine both the agitator capacity to pump the flow and its power consumption during the operation.Then,in order to assess the mixture homogeneity,we evaluated the solid suspension in the desupersaturation reactor following conventional methods and two new proposed methodologies:the first approach is to evaluate the suspension quality in the mixing system by compartment and the second consists on the assessment of the uniform convergence of the solid concentration.Furthermore,we calculated the time required to achieve a full suspension at different solid concentrations.On other hand,we conducted a detailed analysis of the solid distribution dependency on the impeller rotational speed at different solid volume fraction,which allows a good understanding of the parameters controlling the homogenization in the desupersaturator.
文摘The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship between energy and vacuum! So it can be considered that the energy is a function of the vacuum ratio (v). Therefore, we can say that vacuum ratio constitutes a part of space-time. With simple mathematical formula, we can easily obtain the equation of the Energy Vacuum. This gives us the distribution of the energy Vacuum (E) into two parts are inversely proportional from our vacuum energy diagram, the effective energy that the sole responsible for Curvature of space-time fabric, and the lost energy that the responsible of the Gravitational waves [3]. From these equations, we can find that the relationship with Energy and Vacuum ratio is linear which are compatible with Quantum Mechanics laws and Maintains the energy conservation principle. It is also observed that the equations obtained through our theory are Combining relativity and Quantum Mechanics into one continuum. If we take the equations of our theory, we can easily obtain from Curvature of Space-Time Fabric, the Gravity value equation which equals to the square root of energy multiply times the square of the vacuum ratio. On other hand, a curvature matrix and a Time Dilation’s Circle are proposed, which gives us a new method to facilitate the calculations of the parameters involved in the Space-Time Curvature.
文摘Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties.In the present study,through numerical simulations a link is established between the thermal performance of composite materials and their microstructures.First,a two-phase 3D composite structure is modeled,then the RSA(Random Sequential Addition)algorithm and a finite element method(FE)are applied to evaluate the effective thermal conductivity of these composites in the steady-state.In particular,building composites based on gypsum and clay,consolidated with peanut shell additives and/or cork are considered.The numerically determined thermal conductivities are compared with values experimentally calculated using the typical tools of modern metrology,and with available analytical models.The calculated thermal conductivities of the clay-based materials are 0.453 and 0.301 W.m^(−1).K^(−1) with peanut shells and cork,respectively.Those of the gypsum-based materials are 0.245 and 0.165 W.m^(−1).K^(−1) with peanut shells and cork,respectively.It is shown that,in addition to its dependence on the volume fraction of inclusions,the effective thermal conductivity is also influenced by other parameters such as the shape of inclusions and their distribution.The relative deviations,on average,do not exceed 6.8%,which provides evidence for the reliability of the used approach for random heterogeneous materials.
