Search results for "Urban waste"
showing 10 items of 23 documents
Multicriteria performance analysis of an integrated urban wastewater system for energy management
2017
AbstractThe optimization and management of an integrated urban wastewater system is a complex problem involving many processes and variables. The possible control options are defined by several management strategies that may differently impact the economic, operational or environmental performance of the system. The present paper aims to contribute to the environmental and energy sustainability of urban wastewater systems by means of a multicriteria performance analysis. The paper begins with a complete analysis of the system performance in several fields of interest (energy, environment, quality of service, operation, economy and financial resources), and it highlights the management stren…
Città, economia circolare e pianificazione urbanistica
2019
Il progressivo sviluppo delle interdipendenze economiche a scala globale ha influenzato anche la rapida crescita della produzione d’inquinanti e rifiuti di ogni sorta, richiamando l’attenzione della comunità europea e delle nazioni unite sulle politiche urbane, la loro efficacia e la loro integrazione. Le città e le regioni urbane costituiscono le maggiori aree di criticità dove si concentra la maggiore produzione di rifiuti urbani con impatti negativi sulla salute umana e sull’ambiente. Per lungo tempo l’aumento dei rifiuti urbani è stato considerato, come altri inquinanti, un problema alla coda di ogni processo produttivo e di consumo ed è stato affrontato con strumenti settoriali, come d…
Towards more equity concerning quality of Urban Waste Management services in the context of cities
2018
Abstract An innovative combined evaluation approach is proposed in the present paper to deal with the issue of the performance measurement and comparison of Urban Waste Management (UWM) services in the context of cities. The ELECTRE III method is initially considered as tool able to execute a multi-criteria analysis aimed at ranking UWM systems based on their integration and sustainability levels. The latter are comprehensively evaluated via the recently developed “Wasteaware” Integrated and Sustainability Waste Management indicators framework, which takes into account physical components and governance aspects of UWM systems. Then, on the basis on ELECTRE III results, a practical gaps inve…
Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale
2011
The aim of this study was to assess the effect of several operational variables on both biological and separation process performance in a submerged anaerobic membrane bioreactor pilot plant that treats urban wastewater. The pilot plant is equipped with two industrial hollow-fibre ultrafiltration membrane modules (PURON¿ Koch Membrane Systems, 30m 2 of filtration surface each). It was operated under mesophilic conditions (at 33°C), 70days of SRT, and variable HRT ranging from 20 to 6h. The effects of the influent COD/SO 4-S ratio (ranging from 2 to 12) and the MLTS concentration (ranging from 6 to 22gL -1) were also analysed. The main performance results were about 87% of COD removal, efflu…
Use of physicochemical processing in treating urban waste waters
1994
The principal objective of the present study was to compare two clearly defined purification processes in two stages: the periods 1985–1987 (conventional) and 1988–1990 (physico‐chemical). In general, the mean concentrations obtained were lower in the second period. A z‐test for comparing means was applied, but no significant correlation was observed (p ≤ 0.05). The mean concentrations obtained (with some exceptions) are lower in the second period. With the passing of time, the total volume of sewage flow has increased, and hence the load of contaminants has become diluted. The use of physico‐chemical treatment prior to biological processing may be the cause of the increase in cost.
Eutrophication control by lime addition: A preliminary approach in Sicilian reservoirs
2003
Sicilian reservoirs, a vital resource for this densely populated island, are undergoing increased eutrophication processes, due to the lack of urban waste treatment plants and to intense agriculture. Massive blooms of toxic cyanobacteria represent one of the most obvious consequences, and can be dangerous for population health. The possibility of a fast, even if only short term, recovery of water quality through application of lime, was tested through analysis of ion dynamics in two reservoirs, to develop an `emergency plan', to counteract cyanobacterial blooms and to decrease the risk for human health. The results indicate that these water bodies are suitable for lime treatments, even thou…
A Graphical User Interface as a DSS Tool for GHG Emission Estimation from Water Resource Recovery Facilities
2017
A Grafical User Interface (GUI) for the greenhouse gas (GHG) emissions from WWTPs based on four models aimed at quantifying the gas emissions from the aerated tanks (i.e. CAS and MBR reactor), aerobic digesters, secondary clarifiers and anaerobic digesters have been englobed in a GUI in order to provide a valid decision support system (DSS) to the practitioners. The GUI allows to estimate such emissions for the different WWTP phases considered. The GUI has been developed on MATLAB platform and provides as output the GHG emissions in terms of CO2 and N2O fluxes.
Filtration process cost in submerged anaerobic membrane bioreactors (AnMBRs) for urban wastewater treatment
2015
[EN] The objective of this study was to evaluate the effect of the main factors affecting the cost of the filtration process in submerged anaerobic membrane bioreactors (AnMBRs) for urban wastewater (UWW) treatment. Experimental data for CAPEX/OPEX calculations was obtained in an AnMBR system featuring industrial-scale hollow-fiber (HF) membranes. Results showed that operating at J(20) slightly higher than the critical flux results in minimum CAPEX/OPEX. The minimum filtration process cost ranged from Euro0.03 to Euro0.12 per m(3), mainly depending on SGD(m) (from 0.05 to 0.3 m(3)m(-2)h(-1)) and MLSS (from 5 to 25 gL-1). The optimal SGD(m) resulted in approx. 0.1 m(3)m(-2)h(-1).
Real-time optimization of the key filtration parameters in an AnMBR: Urban wastewater mono-digestion vs. co-digestion with domestic food waste
2018
[EN] This study describes a model-based method for real-time optimization of the key filtration parameters in a submerged anaerobic membrane bioreactor (AnMBR) treating urban wastewater (UWW) and UWW mixed with domestic food waste (FW). The method consists of an initial screening to find out adequate filtration conditions and a real-time optimizer applied to a periodically calibrated filtration model for minimizing the operating costs. The initial screening consists of two statistical analyses: (1) Morris screening method to identify the key filtration parameters; (2) Monte Carlo method to establish suitable initial control inputs values. The operating filtration cost after implementing the…
Growth of Arundo donax L. and Cyperus alternifolius L. in a horizontal subsurface flow constructed wetland using pre-treated urban wastewater - a cas…
2013
Constructed wetland systems for wastewater treatment represent an excellent opportunity for the recovery of water resources in those areas subject to prolonged periods of water shortage. This paper presents a study of the efficiency of a pilot horizontal subsurface flow system using pre-treated urban wastewater from a small town in the West of Sicily. The pilot system had a total surface area of 100 m2 with two units. Unit A was planted with Arundo donax L. and unit B with Cyperus alternifolius L. The HLR was 10 cm d-1. The main objectives of research were to evaluate the growth and biomass yield of two macrophytes and determine the removal efficiency of physical-chemical and microbiologica…