Search results for "SANITARIA"

Health Care Waste production: measures and estimates in Joint Hospitals “Civico e Benfratelli, Ascoli e Di Cristina”, Palermo, Italy.

2008

A monitoring work was carried out in October 2006 in one large health care facility located in Palermo. The monitoring consisted in weighing infectious waste containers filled in some Departments purposely chosen. As a second stage of the work a comparison was attempted between the results obtained from the waste production monitoring and the archive data recorded in the same time. A restricted list of purchased products out of the general one was extracted. Such list allows one to calculate approximately the mass of medical devices purchased and their composition. To these materials a reasonable change in humidity after use was attributed. It was possible in this deductive way to draw a pr…

Impulse response tests in completely mixed tanks and reactors. Key assumptions and steps in mathematical developments.

2010

Stimulus-response technique is a method to obtain the Residence Time Distribution (RTD) for the elements of a fluid passing through a vessel. Generally speaking, in reactor science unsteady-state tests may often appear preferable to steady-state since they are made up of a chain of intermediate ones; but without any theoretical necessity holding. In RTD studies, however, non-steady state tests are the only conceivable ones if conservative tracers are employed, because once a transition is over there is no way to reconstruct it and assess the hydraulic behaviour of the tank. Only a series of tests with non-conservative tracers of known disappearance rate would achieve the task, but at the pr…

IMPATTO DELLE ACQUE METEORICHE SUGLI IMPIANTI DI DEPURAZIONE

2014

Greenhouse gas emissions from integrated urban drainage systems: where do we stand?

2017

Integrated urban drainage systems (IUDS) (i.e., sewer systems, wastewater treatment plants and receiving water bodies) contribute to climate change being sources of greenhouse gas emissions (GHG). This paper, produced by the International Working Group on Data and Models, which works under the IWA/IAHR Joint Committee on Urban Drainage, reviews the state-of-the-art and the recently developed modelling tools used to understand and manage GHG emissions from IUDS. Further, open problems and research gaps are discussed, while proposing a framework for handling GHG from IUDS. The literature review reveals that there is a need to strengthen and partially adequate already available mathematical mo…

Global sensitivity analysis in integrated water quality modelling: an application to a real case study

2012

The increasing sensitivity towards water quality environmental issues led to the setting up of water quality integrated modelling approaches and the definition of water quality criteria that better represent the receiving water body quality status. More specifically, compared to the past, the tendency today is to design and manage the whole integrated urban drainage system, i.e. , wastewater treatment plant and receiving water body (RWB) considering each component not separately but jointly. Despite the advantages of a holistic approach for the assessment of the RWB quality state there are some limits that may prevent a straightforward application. Indeed, integrated models are generally ch…

CO-TREATMENT OF LANDFILL LEACHATE IN SBR SYSTEM: LAB-SCALE CASE STUDY REPORT

2015

SUMMARY: Landfill leachate represents nowadays one of the most controversial topics in the waste management cycle. A possible alternative for treating aged landfill leachate is represented by the co-treatment with municipal wastewater (MWW) that provides the necessary amount of biodegradable substances to enhance the development of bacteria metabolism. The correct tradeoff between landfill leachate and MWW represent a key factor in order to avoid inhibition of biomass activity. The paper reports the results of an experimental research carried out on two lab-scale Sequencing Batch Reactors (SBRs) fed with synthetic wastewater and landfill leachate in different percentages (SBR1 fed with 20% …

TREATMENT OF LANDFILL LEACHATE IN SBR SYSTEMS: ANALYSIS OF BIOMASS ACTIVITY BY MEANS OF RESPIROMETRIC TECHNIQUES

2013

In the last decades landfilling has been the main method of municipal solid waste (MSW) disposal in many countries. MSW landfills are usually considered as a large biological reactor where the MSWs undergo anaerobic digestion producing gas and liquid emissions. Aged, or mature leachate, which is produced by older landfills, can be very refractory; for this reason mature leachate is difficult to treat alone, but it can be co-treated with sewage or domestic wastewater. The aim of the study was to investigate the feasibility of co-treatment of landfill leachate and synthetic wastewater in different percentages, in terms of process performance and biomass activity, by means of respirometric tec…

Sensitivity analysis: fundamentals

2015

Sensitivity analysis (SA) is a valuable tool to support the use of mathematical models for environmental systems. Local or global SA (namely, LSA and GSA) are performed in order to better understand processes and to select the most influential factors affecting processes. The main objective of this extended abstract is to provide an informed problem statement of the issues surrounding LSA and GSA applications in the environmental water quality modelling field. Specifically, this paper aims at identifying, for the most popular methods, their potential use, the critical issues to be solved and the limits identified in a comprehensive literature review.

Variance-based sensitivity analysis for wastewater treatment plant modelling

2014

Global sensitivity analysis (GSA) is a valuable tool to support the use of mathematical models that characterise technical or natural systems. In the field of wastewater modelling, most of the recent applications of GSA use either regression-based methods, which require close to linear relationships between the model outputs and model factors, or screening methods, which only yield qualitative results. However, due to the characteristics of membrane bioreactors (MBR) (non-linear kinetics, complexity, etc.) there is an interest to adequately quantify the effects of non-linearity and interactions. This can be achieved with variance-based sensitivity analysis methods. In this paper, the Extend…

Global sensitivity analysis in ASM applications: comparison of the SRC and Extended-FAST method for a UCT-MBR model

2011

In this study global sensitivity analysis is performed to identify influential as well as non-influential parameters in a model of a University Cape Town Membrane Bioreactor (UCT-MBR). In particular, the Standardised Regression Coefficients (SRC) and Extended-FAST sensitivity analysis methods are applied. The sensitivity of model variables towards parameter variation is analysed for CODTOT, SNH4, SNO3, SPO, and MLSS along five reactor compartments. Both methods indicate that the parameters identified as being influential differ from section to section due to the different processes involved. Moreover, the relevant influence of the membrane filtration parameters is detected in the first plan…