scholarly journals Adapted optimization model for planning regional wastewater systems: case study

2017 ◽  
Vol 76 (5) ◽  
pp. 1196-1205 ◽  
Author(s):  
J. A. Zeferino ◽  
M. C. Cunha ◽  
A. P. Antunes

Wastewater systems are of crucial importance to the promotion of sustainable development. Through an integrated planning approach, the costs can be minimized and the resulting benefits maximized. A planning approach at regional level exploits the economies of scale, while achieving a better environmental performance. In this paper we set out a decision support approach for the planning of regional wastewater systems. Optimization models are used, aimed at finding optimal configurations for the location, type and size of the system's infrastructure: sewers, pump stations, and wastewater treatment plants. Solutions are evaluated in terms of the cost of installing, operating and maintaining the infrastructure, and the water quality in the river that receives the treated wastewater. The river water quality varies in accordance with the effluent discharges, and is assessed using environmental parameters. The models are solved with a simulated annealing algorithm complemented by a local improvement procedure. Its application is illustrated through a case study in the Una river basin region, in Brazil.

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1313
Author(s):  
Antonia Arroyo ◽  
Fabián Provoste ◽  
Montserrat Rodríguez ◽  
Ana L. Prieto

Polycyclic aromatic hydrocarbons (PAHs) are a family of organic compounds of widespread presence in the environment. They are recalcitrant, ubiquitous, prone to bioaccumulation, and potentially carcinogenic. Effluent from wastewater treatment plants (WWTPs) constitutes a major source of PAHs into water bodies, and their presence should be closely monitored, especially considering the increasing applications of potable and non-potable reuse of treated wastewater worldwide. Modeling the fate and distribution of PAHs in WWTPs is a valuable tool to overcome the complexity and cost of monitoring and quantifying PAHs. A mechanistic model was built to evaluate the fate of PAHs in both water and sludge lines of a Chilean WWTP. Naphthalene and benzo(a)pyrene were used as models of low-MW and high-MW PAHs. As there were no reported experimental data available for the case study, the influent load was determined through a statistical approach based on reported values worldwide. For both naphthalene and benzo(a)pyrene, the predominant mechanism in the water line was sorption to sludge, while that in the sludge line was desorption. Compared to other studies in the literature, the model satisfactorily describes the mechanisms involved in the fate and distribution of PAHs in a conventional activated sludge WWTP. Even though there is evidence of the presence of PAHs in urban centers in Chile, local regulatory standards do not consider PAHs in the disposal of WWTP effluents. Monitoring of PAHs in both treated effluents and biosolids is imperative, especially when considering de facto reuse and soil amendment in agricultural activities are currently practiced downstream of the studied WWTP.


2014 ◽  
Vol 33 (4) ◽  
Author(s):  
Henrieta Pavolová ◽  
Adriana Csikósová ◽  
Tomáš Bakalár

AbstractThe development of the regions in Slovakia in recent years has significant disparities in both so-cio-economic as well as environmental issues, as evidenced by the eight environmentally polluted areas (these areas are highly urbanised with industrial agglomerations or intensive agricultural production).This article deals with a management system model of regional by implementation of projects in environmental field of water management with application-specific benefits and risks arising from the process of their implementation in relation to regional development. It analyses projects in the area of water management of one of the regions of Slovakia, KoŠice region in particular, in terms of connection to public water duct and sewer, identifes a strategy for development of the region and its socio-economic and environmental benefits based on the analysis of drinking water, the quan-tity and quality of treated wastewater through wastewater treatment plants (WTPs). It identifes the infuencing factors of benefits and risks and proposes procedure for solving at various stages.


2019 ◽  
Author(s):  
CI Chemistry International ◽  
Elias Barsenga Hassen ◽  
Abraham M. Asmare

Recently, process control in wastewater treatment plants (WWTPs) is, mostly accomplished through examining the quality of the water effluent and adjusting the processes through the operator’s experience. This practice is inefficient, costly and slow in control response. A better control of WTPs can be achieved by developing a robust mathematical tool for performance prediction. Due to their high accuracy and quite promising application in the field of engineering, Artificial Neural Networks (ANNs) are attracting attention in the domain of WWTP predictive performance modeling. This work focuses on applying ANN with a feed-forward, back propagation learning paradigm to predict the effluent water quality of the Habesha brewery WTP. Data of influent and effluent water quality covering approximately an 11-month period (May 2016 to March 2017) were used to develop, calibrate and validate the models. The study proves that ANN can predict the effluent water quality parameters with a correlation coefficient (R) between the observed and predicted output values reaching up to 0.969. Model architecture of 3-21-3 for pH and TN, and 1-76-1 for COD were selected as optimum topologies for predicting the Habesha Brewery WTP performance. The linear correlation between predicted and target outputs for the optimal model architectures described above were 0.9201 and 0.9692, respectively.


2018 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Medhat Moustafa ◽  
Diaa Hamdy Seif ◽  
Walid Elbarki ◽  
Mohamed Reda Soliman

The simulation of hydrodynamics water quality in ponds is a developing tool that worth studying in order to understand their internal processes and interactions. Pond design involves several physical, hydrological, geometrical, biological and dynamic variables to provide high hydrodynamic efficiency and maximum substrate utilization rates.  Computational fluid dynamic modelling (CFD) allows the combination of these factors to predict the behavior of ponds by using different configurations. In this research mathematical model developed by Danish Hydraulic Institute (DHI), was formulated to simulate WQ parameter. This model was calibrated and used to simulate a scenario to improve study reach water quality in polluted lakes. The study applied on El-Burullus Lake, which is the second largest northern lake in Egypt which belongs to high eutrophic lake type and suffers from several problems. The model was run at steady and variable state with raw wastewater to study the real effect of the polluted drains, which discharge high amount of polluted wastewater into the El-Burullus Lake and know the lake situation after make baffles scenario. The major functions performed by baffles are to reduce hydraulic short-circuiting and to provide a submerged surface which can encourage the growth of attached biomass. Attached biomass growing on the surface of the baffles could increase the total mass of organisms in the pond and thus improve the treatment efficiency and therefore reduce the eutrophication rate in the pond such as (NH3-N, PO4-P and NO3-N). Results showed that there are a significant variance between the rate of NH3-N, PO4-P and NO3-N  before and after make baffles, and the overlap between baffles (L=0.50 baffle) is more efficient than no overlap. In conclusion, waste ponds and be improved easily and economically to be more efficient by making baffles in the lake which can increase the water velocity, avoided the dead zones area and reduce the eutrophic concentration.


Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 173
Author(s):  
Mike Donn ◽  
Debbie Reed ◽  
Joanne Vanderzalm ◽  
Declan Page

Treated wastewater (TWW) infiltration into non-potable aquifers has been used for decades in Western Australia for disposal and reuse. These wastewater treatment plants (WWTPs) are mostly pond systems, infiltrating secondary TWW with some activated sludge. There is no disinfection of TWW pre-infiltration. This study gave an opportunity to study the fate of Escherichia coli (E. coli) in aquifers, using compliance monitoring data (2006–2016) and is relevant if water reuse is to be implemented at these sites in the future. Microbiological water quality data (E. coli) were evaluated using an advanced statistical method able to incorporate the highly censored data at full scale operational infiltration sites. Subsurface E. coli removal from TWW was observed at all 17 infiltration sites investigated. Most sites (14) had less than six detections of E. coli in groundwater (58–100% non-detects; 7–117 samples/bore), thus the statistical method could not be applied. The observations could be used to infer between 1 to >3 log10 removal for E. coli. The remaining three sites had sufficient detections for probabilistic modelling analysis, the median removal efficiency for E. coli was quantified as 96% to greater than 99%, confirming at least 1 log10 removal with potential for several log10 removal. Reductions could not be explained through dilution with the native groundwater alone as there was a high proportion of TWW in observation bores. The observed reductions are likely the result of bacteria retention and inactivation in the aquifer. The magnitude of microbiological water quality improvement highlights the sustainable and reliable use of the aquifer to improve water quality to levels appropriate for low- and medium-risk non-potable uses without using engineered disinfection methods.


2010 ◽  
Vol 12 (4) ◽  
pp. 380-395 ◽  
Author(s):  
Lorenzo Benedetti ◽  
Webbey De Keyser ◽  
Ingmar Nopens ◽  
Peter A. Vanrolleghem

Process choice and dimensioning of wastewater treatment plants (WWTPs) is difficult while ensuring regulatory standards are met and cost-efficiency is maintained. This step only accounts for a small fraction of the upfront costs, but can lead to substantial savings. This paper illustrates the results of a systematic methodology to evaluate system upgrade options by means of dynamic modelling. In contrast to conventional practice, the presented approach allows the most appropriate trade-off between cost of measures and effluent quality to be chosen and the reliability of a process layout to be assessed by means of uncertainty analysis. In a hypothetical case study, thirteen WWTP upgrade options are compared in terms of their effluent quality and economic performance. A further comparison of two options with regard to the resulting receiving water quality reveals the paramount importance of this aspect, and highlights the inadequacy of evaluation frameworks limited to the performance relative to a sub-system (WWTP effluent) when a wider perspective (as induced by the EU Water Framework Directive) has to be adopted.


2017 ◽  
Vol 75 (8) ◽  
pp. 1862-1872 ◽  
Author(s):  
Roni Penn ◽  
Manfred Schütze ◽  
Jens Alex ◽  
Eran Friedler

Together with significant water savings that onsite greywater reuse (GWR) may provide, it may also affect the performance of urban sewer systems and wastewater treatment plants (WWTPs). In order to examine these effects, an integrated stochastic simulation system for GWR in urban areas was developed. The model includes stochastic generators of domestic wastewater streams and gross solids (GSs), a sewer network model which includes hydrodynamic simulation and a GS transport module, and a dynamic process model of the WWTP. The developed model was applied to a case study site in Israel. For the validation of the sewer simulator, field experiments in a real sewer segment were conducted. The paper presents the integration and implementation of these modules and depicts the results of the effects of various GWR scenarios on GS movement in sewers and on the performance of the WWTP.


2011 ◽  
Vol 4 (5) ◽  
pp. 70-72
Author(s):  
Cristina Roşu ◽  
◽  
Ioana Piştea ◽  
Carmen Roba ◽  
Mihaela Mihu ◽  
...  

2018 ◽  
Vol 2 (1) ◽  
pp. 18-20 ◽  
Author(s):  
Muhammad Usman ◽  
Mian Bilal Khalid ◽  
Hafsa Yasin ◽  
Abdul Nasir, ◽  
Ch Arslan

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