Establishing a treatment process for practical and economic disposal of car wash wastewater has become an urgent environmental concern. Photo-Fenton's process as one of the advanced oxidation processes is a potentially useful oxidation process in treating such wastewater. Lab-scale experiments with UV source, coupled with Fenton's reagent, showed that hydrocarbon oil is degradable through such a process. The feasibility of photo-Fenton's process to treat wastewater from a car wash is investigated in the present study. A factorial design based on the response surface methodology was applied to optimize the photo-Fenton oxidation process conditions using chemical oxygen demand (COD) reduction as the target parameter to optimize. The reagent (Fe 2+ and H 2 O 2 concentration) and pH are used as the controlling factors to be optimized. Maximal COD reduction (91.7%) was achieved when wastewater samples were treated at pH 3.5 in the presence of hydrogen peroxide and iron in amounts of 403.9 and 48.4 mg/L, respectively.
A hydro-environmental model investigated the consequences of closing a power plant. Model simulated water quality for three scenarios before and after closing the plant. Dilution scenario gave better water quality results than direct discharges scenario. Direct discharges scenario showed an increased stratification of the estuary waters. MPB 5641No. of Pages 1, Model 5G Scenarios1 and 2, showed almost similar E. coli distribution patterns while Scenario3 displayed signifi-30 cantly higher E. coli concentrations due to the increased stratification caused by the lack of prior dilution.
The revised Bathing Water Directive (2006/7/EC) requires EU member states to minimise the risk to public health from faecal pollution at bathing waters through improved monitoring and management approaches. While increasingly sophisticated measurement methods (such as microbial source tracking) assist in the management of bathing water resources, the use of deterministic predictive models for this purpose, while having the potential to provide decision making support, remains less common.This study explores an integrated, deterministic catchment-coastal hydro-environmental model as a decision-making tool for beach management which, based on advance predictions of bathing water quality, can inform beach managers on appropriate management actions (to prohibit bathing or advise the public not to bathe) in the event of a poor water quality forecast. The model provides a 'moving window' five-day forecast of E. coli at a bathing water compliance point off the Irish coast and the accuracy of bathing water management decisions were investigated for model predictions under two scenarios over the period from the 11 th August to the 5 th September, 2012. Decisions for Scenario 1 were based on model predictions where rainfall forecasts from a meteorological source (www.yr.no) were used to drive the rainfall-runoff processes in the catchment component of the model, and for Scenario 2, were based on predictions that were improved by incorporating real-time rainfall data Manuscript Click here to view linked References 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 from a sensor network within the catchment into the forecasted meteorological input data. The accuracy of the model in the decision-making process was assessed using the contingency table and its metrics.The predictive model gave reasonable outputs to support appropriate decision making for public health protection. Scenario 1 provided real-time predictions that, on 77% of instances during the study period where both predicted and E. coli concentrations were available, would correctly inform a beach manager to either take action to mitigate for poor bathing water quality or take no action. However, Scenario 1 also provided data to support a decision to take action (when none was necessary -a type I error) in 4% of instances and to take no action (when action was required -a type II error) in 19% of the instances analysed. Type II errors are critical in terms of public health protection given that for this error, bathers can be exposed to risks from poor bathing water quality. Scenario 2, on the other hand, provided predictions that would support correct management actions for 79% of the instances but would result in type I and type II errors for 4% and 17% of the instances respectively.Comparison of Scenarios 1 and 2 for this study indicate that Scenario 2...
Publication informationEnvironmental Modeling and Assessment, 16 (4): 369-384Publisher Springer AbstractThis paper compares a 3-dimensional hydro-ecological model with a 2-dimensional model simulating the distribution and fate of Escherichia Coli (E.Coli) discharges from a sewage treatment plant discharging into Dublin Bay, Ireland. Before being discharged, the effluent from the sewage treatment plant is mixed with cooling water from a thermal generation plant resulting in a warm buoyant sewage plume that can be 7 − 9 o C higher than the ambient water in the Bay. The mixing of the stratified plume is complicated by the tidal currents which transport the plume into and out of the estuary. These processes have a direct impact on the transport and fate of E.Coli and the model comparison demonstrates that a three-dimensional model is required to adequately represent the mixing processes in such a stratified environment.The modelling followed a two-step procedure. First, hydrodynamic simulations of water levels and flow velocities in Dublin Bay were performed using the three-dimensional model TELEMAC-3D. The resulting water level and flow velocity fields were used by the three-dimensional water quality model, SUBIEF-3D to model the transport and fate of E.Coli in the Bay.Further simulations were performed in which the wind effects on the E.Coli dispersion were included. The water quality simulation was repeated using the 2-dimensional, depth-averaged, hydrodynamic model TELEMAC-2D to compare with the threedimensional simulations. The results showed that the three-dimensional model gives an adequate representation of the hydrodynamics and water quality in the Bay while the two-dimensional, depth-averaged, water quality model (in comparison to the threedimensional model) delays the timing of the delivery of E.Coli to the Bay and seriously underestimats the decay rate of E.Coli and the effect of wind on the movement of the buoyant plume of pollution.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.