Search results for " ingegneria"

Rainwater Reuse in Urban Areas: A Mathematical Model and a Long-Term Modelling Approach

2018

Natural water resources are becoming increasingly limited due to global-scale climate change and water availability issues have become so severe that they must be addressed. Given these issues, reuse of wastewater and rainwater provides a promising way to cope with water shortages. This paper describes an investigation into the efficiency of rainwater usage systems. A conceptual model was built to assess the behaviour of rainwater tanks and their effectiveness in coping with water shortages. The study is based on a long-term simulation (12 years) of different rainwater reuse tank schemes. The associated reductions in residential freshwater demand (water reuse efficiency) and wet-weather run…

Treatment of high strength industrial wastewater with membrane bioreactors for water reuse: Effect of pre-treatment with aerobic granular sludge on s…

2019

Abstract In this study, the treatment of citrus wastewater with membrane bioreactors (MBRs) under different configurations was investigated for water reuse. In particular, one MBR and one aerobic granular sludge MBR (AGS + MBR) bench scale plants were operated for 60 days. The experimental campaign was divided into two periods. In Phase I, a conventional hollow fiber MBR was employed for the treatment of the raw high strength wastewater, whereas in Phase II a combination of in-series reactors (AGS + MBR) was adopted for the treatment of the high strength citrus wastewater The results demonstrated that both plant configurations enabled very high COD removal, with average values close to 99%.…

Price dispersion in the Italian airline industry: the role of competition and online travel agents

2013

An Early Beginning of Citizen Science: Adolescents Experiencing Urban Energy Usages and Air Pollution

2021

Here, we report on the process and development of high school science projects, which were inspired by a citizen science program focused on urban monitoring. We gathered and discussed two 1980s projects’ data, involving 2600 students, 80 teachers, 15 scientists and 20 stakeholders. We added recent survey data from speaking with the former participants. Our analysis revealed key findings: (1) the process of a student-driven science investigation engages students in the scientific practices; (2) it is important to bring together scientists, teachers and students, reflecting the importance of multi-dimensional learning; and (3) citizen science was born before the 1990s, when the term came into…

Biological nitrogen and phosphorus removal in membrane bioreactors: model development and parameter estimation

2012

Membrane bioreactors (MBR) are being increasingly used for wastewater treatment. Mathematical modeling of MBR systems plays a key role in order to better explain their characteristics. Several MBR models have been presented in the literature focusing on different aspects: biological models, models which include soluble microbial products (SMP), physical models able to describe the membrane fouling and integrated models which couple the SMP models with the physical models. However, only a few integrated models have been developed which take into account the relationships between membrane fouling and biological processes. With respect to biological phosphorus removal in MBR systems, due to th…

Negotiation mechanisms for capacity allocation in distributed enterprises

2003

Abstract The paper proposes an agent based approach for the capacity allocation in distributed enterprises, characterized by complex and articulated organizations and by geographically distributed production capacities contended by many product families. In such a scenario the process of allocating the production capacity to the single customer order is one the major bottlenecks of the production planning activity as far as many organizational decisional levels are involved and market turbulence implies a continuous retuning of the capacity allocation plan. A high grade of reactiveness is needed. Agent based approaches and negotiation models, by decentralizing the decisional control and sim…

A practical protocol for calibration of nutrient removal wastewater treatment models

2011

Activated sludge models can be very useful for designing and managing wastewater treatment plants (WWTPs). However, as with every model, they need to be calibrated for correct and reliable application. Activated sludge model calibration is still a crucial point that needs appropriate guidance. Indeed, although calibration protocols have been developed, the model calibration still represents the main bottleneck to modelling. This paper presents a procedure for the calibration of an activated sludge model based on a comprehensive sensitivity analysis and a novel step-wise Monte Carlo-based calibration of the subset of influential parameters. In the proposed procedure the complex calibration i…

Occurrence of illicit drugs in two wastewater treatment plants in the South of Italy

2017

In this study the occurrence and the behavior of illicit drugs and their metabolites have been investigated for two wastewater treatment plants (WWTPs) (namely, WWTP-1 and WWTP-2) located in Sicily (island of Italy). Samples were analyzed for methamphetamine, cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA), methadone (METH), 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), 3,4-methylenedioxy amphetamine (MDA); 3,4-methylenedioxy ethylamphetamine (MDEA), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) and Benzoylecgonine (BEG). The BEG, COC, MOR and THC-COOH were found at the highest concentration in both WWTPs. The Wastewater-based epidemiology calculation for BEG, COC…

Receiving water quality assessment: comparison between simplified and detailed integrated urban modelling approaches

2010

Urban water quality management often requires use of numerical models allowing the evaluation of the cause–effect relationship between the input(s) (i.e. rainfall, pollutant concentrations on catchment surface and in sewer system) and the resulting water quality response. The conventional approach to the system (i.e. sewer system, wastewater treatment plant and receiving water body), considering each component separately, does not enable optimisation of the whole system. However, recent gains in understanding and modelling make it possible to represent the system as a whole and optimise its overall performance. Indeed, integrated urban drainage modelling is of growing interest for tools to …

Uncertainty in urban stormwater quality modelling: The influence of likelihood measure formulation in the GLUE methodology

2009

In the last years, the attention on integrated analysis of sewer networks, wastewater treatment plants and receiving waters has been growing. However, the common lack of data in the urban water-quality field and the incomplete knowledge regarding the interpretation of the main phenomena taking part in integrated urban water systems draw attention to the necessity of evaluating the reliability of model results. Uncertainty analysis can provide useful hints and information regarding the best model approach to be used by assessing its degrees of significance and reliability. Few studies deal with uncertainty assessment in the integrated urban-drainage field. In order to fill this gap, there ha…