The Experts below are selected from a list of 16035 Experts worldwide ranked by ideXlab platform
Siti Safirah Rashid - One of the best experts on this subject based on the ideXlab platform.
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assessing environmental impacts of large centralized wastewater treatment plants with combined or separate Sewer Systems in dry wet seasons by using lca
Environmental Science and Pollution Research, 2020Co-Authors: Siti Safirah Rashid, Yongqiang LiuAbstract:Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two Sewer Systems, i.e. combined and separate Sewer Systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m3 treated wastewater (FU1) and as per kg PO43-eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined Sewer System (with Pearson correlation coefficient r at 0.66) or a separate Sewer System (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while Sewer System, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate Sewer System. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.
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Assessing environmental impacts of large centralized wastewater treatment plants with combined or separate Sewer Systems in dry/wet seasons by using LCA
Environmental Science and Pollution Research, 2020Co-Authors: Siti Safirah RashidAbstract:Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two Sewer Systems, i.e. combined and separate Sewer Systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m^3 treated wastewater (FU1) and as per kg PO_4^3-eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined Sewer System (with Pearson correlation coefficient r at 0.66) or a separate Sewer System (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while Sewer System, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate Sewer System. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.
Tsangjung Chang - One of the best experts on this subject based on the ideXlab platform.
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a novel approach to model dynamic flow interactions between storm Sewer System and overland surface for different land covers in urban areas
Journal of Hydrology, 2015Co-Authors: Tsangjung Chang, Chiaho Wang, Albert S ChenAbstract:In this study, we developed a novel approach to simulate dynamic flow interactions between storm Sewers and overland surface for different land covers in urban areas. The proposed approach couples the one-dimensional (1D) Sewer flow model (SFM) and the two-dimensional (2D) overland flow model (OFM) with different techniques depending on the land cover type of the study areas. For roads, pavements, plazas, and so forth where rainfall becomes surface runoff before entering the Sewer System, the rainfall–runoff process is simulated directly in the 2D OFM, and the runoff is drained to the Sewer network via inlets, which is regarded as the input to 1D SFM. For green areas on which rainfall falls into the permeable ground surface and the generated direct runoff traverses terrain, the deduction rate is applied to the rainfall for reflecting the soil infiltration in the 2D OFM. For flat building roofs with drainage facilities allowing rainfall to drain directly from the roof to Sewer networks, the rainfall–runoff process is simulated using the hydrological module in the 1D SFM where no rainfall is applied to these areas in the 2D OFM. The 1D SFM is used for hydraulic simulations in the Sewer network. Where the flow in the drainage network exceeds its capacity, a surcharge occurs and water may spill onto the ground surface if the pressure head in a manhole exceeds the ground elevation. The overflow discharge from the Sewer System is calculated by the 1D SFM and considered a point source in the 2D OFM. The overland flow will return into the Sewer network when it reaches an inlet that connects to an un-surcharged manhole. In this case, the inlet is considered as a point sink in the 2D OFM and an inflow to a manhole in the 1D SFM. The proposed approach was compared to other five urban flood modelling techniques with four rainfall events that had previously recorded inundation areas. The merits and drawbacks of each modelling technique were compared and discussed. Based on the simulated results, the proposed approach was found to simulate floodings closer to the survey records than other approaches because the physical rainfall–runoff phenomena in urban environment were better reflected.
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inundation simulation for urban drainage basin with storm Sewer System
Journal of Hydrology, 2000Co-Authors: Shiuanhung Chen, Tsangjung ChangAbstract:An urban inundation model, combining a storm Sewer model SWMM, two-dimensional (2D) diffusive overland-flow model and operations of pumping stations, has been developed to simulate inundation in urban areas caused by the surcharge of storm Sewers and outlet pumping stations. The movement of water in the studied urban watershed is characterized by two components, namely, the storm Sewer flow component and the surcharge-induced inundation component. SWMM is employed to solve the storm Sewer flow component and to provide the surcharged flow hydrographs for surface runoff exceeding the capacity of the storm Sewers. The 2D diffusive overland-flow model considering the non-inertia equation with Alternative Direction Explicit numerical scheme is then used to calculate the detailed inundation zones and depths due to the surcharged water on overland surface. Drainage by pumping stations at outlets of the storm Sewer System has also been taken into consideration. The parameters of the model are calibrated and verified for discrete storms. The combined model is suitable for analysis of inundation on urban areas due to overflow of storm Sewers and flooding caused by failure of pumping stations. Simulated results can be applied to establish flood-mitigation measures.
Yongqiang Liu - One of the best experts on this subject based on the ideXlab platform.
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assessing environmental impacts of large centralized wastewater treatment plants with combined or separate Sewer Systems in dry wet seasons by using lca
Environmental Science and Pollution Research, 2020Co-Authors: Siti Safirah Rashid, Yongqiang LiuAbstract:Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two Sewer Systems, i.e. combined and separate Sewer Systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m3 treated wastewater (FU1) and as per kg PO43-eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined Sewer System (with Pearson correlation coefficient r at 0.66) or a separate Sewer System (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while Sewer System, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate Sewer System. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.
Maria Viklander - One of the best experts on this subject based on the ideXlab platform.
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using distributed temperature sensing dts for locating and characterising infiltration and inflow into foul Sewers before during and after snowmelt period
Water, 2019Co-Authors: Oleksandr Panasiuk, R P S Schilperoort, Cornelis De Haan, J G Langeveld, Annelie Hedstrom, Erik Liefting, Maria ViklanderAbstract:Infiltration and inflow (I/I) into Sewers cause negative effects on the Sewer System, wastewater treatment plant and environment. Identifying the causes and locating the inflows is necessary in order to address the I/I problem. This paper focuses on using distributed temperature sensing (DTS) for identifying, locating and characterising I/I into a Sewer System during the end of winter–beginning of summer transition period under dry and wet weather conditions. During snowmelt, several locations with I/I were identified, while these locations did not show I/I during storm events after the snowmelt. In addition, during a very heavy storm after the snowmelt period, I/I was found at other locations. Therefore, DTS was demonstrated to be effective in identifying the type of I/I and in locating I/I. Finally, I/I monitoring campaigns in cold climates should take into account the variety of pathways of I/I during snowmelt and during rainfall.
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the effects of initial soil moisture conditions on swale flow hydrographs
Hydrological Processes, 2018Co-Authors: Hendrik Rujner, Gunther Leonhardt, Jiri Marsalek, Annamaria Perttu, Maria ViklanderAbstract:The effects of soil water content (SWC) on the formation of run‐off in grass swales draining into astorm Sewer System were studied in two 30‐m test swales with trapezoidal cross sections. Swale1 wa ...
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using distributed temperature sensing for locating infiltration and inflow into foul Sewers in cold climate
8th International Conference on Sewer Processes and Networks Rotterdam August 31-September 2 2016, 2016Co-Authors: Oleksandr Panasiuk, R P S Schilperoort, Cornelis De Haan, J G Langeveld, Annelie Hedstrom, Erik Liefting, Maria ViklanderAbstract:Infiltration and inflow (I/I) into the wastewater Systems cause negative effects on both the Sewer System and wastewater treatment plant. Monitoring of I/I rate and locating the inflows are require ...
Albert S Chen - One of the best experts on this subject based on the ideXlab platform.
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a novel approach to model dynamic flow interactions between storm Sewer System and overland surface for different land covers in urban areas
Journal of Hydrology, 2015Co-Authors: Tsangjung Chang, Chiaho Wang, Albert S ChenAbstract:In this study, we developed a novel approach to simulate dynamic flow interactions between storm Sewers and overland surface for different land covers in urban areas. The proposed approach couples the one-dimensional (1D) Sewer flow model (SFM) and the two-dimensional (2D) overland flow model (OFM) with different techniques depending on the land cover type of the study areas. For roads, pavements, plazas, and so forth where rainfall becomes surface runoff before entering the Sewer System, the rainfall–runoff process is simulated directly in the 2D OFM, and the runoff is drained to the Sewer network via inlets, which is regarded as the input to 1D SFM. For green areas on which rainfall falls into the permeable ground surface and the generated direct runoff traverses terrain, the deduction rate is applied to the rainfall for reflecting the soil infiltration in the 2D OFM. For flat building roofs with drainage facilities allowing rainfall to drain directly from the roof to Sewer networks, the rainfall–runoff process is simulated using the hydrological module in the 1D SFM where no rainfall is applied to these areas in the 2D OFM. The 1D SFM is used for hydraulic simulations in the Sewer network. Where the flow in the drainage network exceeds its capacity, a surcharge occurs and water may spill onto the ground surface if the pressure head in a manhole exceeds the ground elevation. The overflow discharge from the Sewer System is calculated by the 1D SFM and considered a point source in the 2D OFM. The overland flow will return into the Sewer network when it reaches an inlet that connects to an un-surcharged manhole. In this case, the inlet is considered as a point sink in the 2D OFM and an inflow to a manhole in the 1D SFM. The proposed approach was compared to other five urban flood modelling techniques with four rainfall events that had previously recorded inundation areas. The merits and drawbacks of each modelling technique were compared and discussed. Based on the simulated results, the proposed approach was found to simulate floodings closer to the survey records than other approaches because the physical rainfall–runoff phenomena in urban environment were better reflected.