Incineration of Pre-Treated Municipal Solid Waste (MSW) for Energy Co-Generation in a Non-Densely Populated Area

Abstract: The planning actions in municipal solid waste (MSW) management must follow strategies aimed at obtaining economies of scale. At the regional basin, a proper feasibility analysis of treatment and disposal plants should be based on the collection and analysis of data available on production rate and technological characteristics of waste. Considering the regulations constraint, the energy recovery is limited by the creation of small or medium-sized incineration plants, while separated collection strongly influences the heating value of the residual MSW. Moreover, separated collection of organic fraction in non-densely populated area is burdensome and difficult to manage. The paper shows the results of the analysis carried out to evaluate the potential energy recovery using a combined cycle for the incineration of mechanically pre-treated MSW in Basilicata, a non-densely populated region in Southern Italy. In order to focalize the role of sieving as pre-treatment, the evaluation on the MSW sieved fraction heating value was presented. Co-generative (heat and power production) plant was compared to other MSW management solutions (e.g., direct landfilling), also considering the environmental impact in terms of greenhouse gases (GHGs) emissions

Fuzzy Logic and Neuro-Fuzzy Networks for Environmental Hazard Assessment

Pollution and management of the environment are serious problems which concern the entire planet; the main responsibility should be attributed to human activities that contribute significantly to damage the environment, leading to an imbalance of natural ecosystems. In recent years, numerous studies focused on the three environmental compartments: soil, water and air. The pollution of groundwater is a widespread problem. The causes of pollution are often linked to human activities, including waste disposal. Solid waste management has become an important environmental issue in industrialized countries. The most serious problems are related to solid waste disposal. Landfill is still the most used disposal technique but not the safest. In fact, even controlled landfills could easily incur in the breakdown of containment elements. This breakdown could cause contamination of aquifer that is environmental pollution. Such contamination can be mitigated by performing remediation and environmental restoration. The assessment of environmental pollution risk can be performed with different degrees of detail and precision. Various statistical and mathematical models can be used for a qualitative risk assessment. The planning of a program for environmental remediation and restoration can be supported by expeditious methodologies that allow to obtain a hierarchical classification of contaminated sites. The literature offers some expeditious and qualitative methods including fuzzy logic (Zadeh, 1965), neural networks and neuro-fuzzy networks, which are more objective methods. The three artificial intelligence systems differ among themselves in some respects: fuzzy inference system learns knowledge of data only through the fuzzy rules; neural network is able to learn knowledge of data using the weights of synaptic connections; neuro-fuzzy systems are able to learn knowledge of neural data with neural paradigm and represent it in the form of fuzzy rules. Fuzzy logic was founded in 1965 by Zadeh. The first applications date back to the nineties. They were mainly used to control industrial processes, household electrical appliances and means of transport. Later, this approach was used in several fields including the environment. In fact it could be used for assessing environmental risk related to contamination of groundwater. The fuzzy approach is advantageous because it allows a quick assessment of the risk, but is disadvantageous because of the increasing complexity in the definition of fuzzy rules along with the increasing of the number of parameters. In many situations, when the number of parameters are considered high in the analysis, application of these techniques is cumbersome and complex and could be used for neuro-fuzzy models. These models reduce the complexity because they use training data. The neuro-fuzzy model were supported by a sensitivity analysis in order to address the problem of subjectivity and uncertainty of model input data

MODELLING OF AEROBIC REACTORS FOR LANDFILL METHANE OXIDATION

Landfill gas is produced by anaerobic degradation of organic waste. Landfills are one of the principal anthropogenic sources of atmospheric methane, a strong greenhouse gas. At the present, abatement techniques of landfill biogas consist in the energy recovery for the production of electrical energy, when the percentage of methane is in the order of 40 - 50% v/v. In this case, the complete combustion and the subsequent functioning of the engine for the production of energy is ensured. For percentages of the order of 30% v/v, the extracted biogas is conveyed to a system of gas flare which ensures the complete thermal oxidation before entering into the atmosphere. In all cases of low production of landfill gas or low methane concentration (small landfills or landfills in the terminal phase of stabilization), the combustion of biogas is difficult. In such conditions the biogas produced is often directly emitted into the atmosphere. Technical specifications for the operation of gas flares indicate a minimum flow of 50 Nm3/h and a methane concentration of 30% v/v. A flow of this size is equivalent to an annual emission of approximately 3200 tons of CO2eq. It is however known that methane can be metabolized by specific CH4-reducing microorganisms. The aim of this work is the evaluation of the efficiency of an aerobic bioreactor for the oxidation of methane, through the application of a mathematical model representative of the biological oxidation process, by implementing a calculation algorithm. The developed mathematical model describes the evolution of the phenomenon of methane oxidation. It is able to evaluate the efficiency of the system under varying operating conditions with the aim of optimizing the performance of the "biofilter". Literature data have been used in order to build the model and to drawing up the equations that describe the process. Through the implementation of the model in the MATLAB software, good results on the performance of this system were obtained. The factors that mostly affect the efficiency of the process of methane oxidation and that actually regulate the entire process have been highlighted in this work. The results obtained from the mathematical model showed that the biofilter system is simple to implement and manage and allows the achievement of high efficiency of methane oxidation

reuse study of sustainable wastewater in agroforestry domain of marrakesh city

The current work aims to perform a feasibility study of sustainable urban wastewater reuse in agroforestry domain of Marrakesh city in order to assess the environmental and the sustainability of urban wastewater reuse in agroforestry irrigation. To this end, wastewater physicochemical characteristics from Marrakesh full-scale wastewater treatment plant, soil physicochemical analysis and climate analysis were investigated. Finally, treated urban wastewater potential production in Marrakesh WWTP and challenge related to its reuse are provided. The obtained results of the present study reveals the feasibility of this practice in Marrakesh region. Regarding the actual situation, climate analysis highlight that the local climatic conditions is an ultimate challenge for water resources; soil analysis reveals a loss of soil fertility due to the decline in soil organic matter. To face this condition, treated urban wastewater reuse is a sustainable and promising strategy to face water scarcity, enhance soil fertility, preserve natural resources, develop local products and improve living conditions of agriculture and farmers. Keywords: Urban wastewater, Physicochemical analysis, Wastewater reuse, Climate analysis, Arid climate, Marrakes

Critical analysis of the integration of residual municipal solid waste incineration and selective collection in two Italian tourist areas

Municipal solid waste management is not only a contemporary problem, but also an issue at world level. In detail, the tourist areas are more difficult to be managed. The dynamics of municipal solid waste production in tourist areas is affected by the addition of a significant amount of population equivalent during a few months. Consequences are seen in terms of the amount of municipal solid waste to be managed, but also on the quality of selective collection. In this article two case studies are analyzed in order to point out some strategies useful for a correct management of this problem, also taking into account the interactions with the sector of waste-to-energy. The case studies concern a tourist area in the north of Italy and another area in the south. Peak production is clearly visible during the year. Selective collection variations demonstrate that the tourists' behavior is not adequate to get the same results as with the resident population. © The Author(s) 2014

Current Trends in Gelatin-Based Drug Delivery Systems

Gelatin is a highly versatile natural polymer, which is widely used in healthcare-related sectors due to its advantageous properties, such as biocompatibility, biodegradability, low-cost, and the availability of exposed chemical groups. In the biomedical field, gelatin is used also as a biomaterial for the development of drug delivery systems (DDSs) due to its applicability to several synthesis techniques. In this review, after a brief overview of its chemical and physical properties, the focus is placed on the commonly used techniques for the development of gelatin-based micro- or nano-sized DDSs. We highlight the potential of gelatin as a carrier of many types of bioactive compounds and its ability to tune and control select drugs' release kinetics. The desolvation, nanoprecipitation, coacervation, emulsion, electrospray, and spray drying techniques are described from a methodological and mechanistic point of view, with a careful analysis of the effects of the main variable parameters on the DDSs' properties. Lastly, the outcomes of preclinical and clinical studies involving gelatin-based DDSs are thoroughly discussed

Efficacy and Safety of Long-Term Treatment with Stiripentol in Children and Adults with Drug-Resistant Epilepsies: A Retrospective Cohort Study of 196 Patients

BACKGROUND: Stiripentol is an antiseizure medication with multiple potential mechanisms of action, indicated as adjunctive therapy in people with Dravet syndrome, whose seizures are not adequately controlled with clobazam and valproate. However, there are scattered data on its efficacy in other epilepsy aetiologies and types. We previously reported our single-centre experience on the efficacy of adjunctive stiripentol treatment in a cohort of 132 patients with different types of refractory epilepsies. OBJECTIVE: We aimed to expand our analysis to a larger cohort of 196 patients with a long-term follow-up. METHODS: We retrospectively evaluated long-term efficacy, tolerability and predictors of treatment response in 196 patients with a long-term follow-up (range 0.5-232.8 months). RESULTS: After an initial median follow-up of 3 months after stiripentol introduction, we observed a responder rate of 53% including seizure freedom in 9%. At subsequent follow-ups at 12 and 24 months, responder rates were 29% and 22%, respectively. Aetiology was associated with sustained response over time, with Dravet syndrome being the aetiology with the highest responder rate (64%) at 48 months compared with syndromes with other genetic causes (13%) or unknown aetiology (38%). A higher responder rate over time was also observed in patients with generalised (44%) and combined focal and generalised epilepsies (28%) than in patients with focal epilepsies (20%). The highest relapse free-survival was observed when stiripentol was initiated at the youngest age (0-4 years) or in adulthood. The retention rate (i.e. proportion of patients who continued stiripentol with no change in either pharmacological or non-pharmacological therapy) was 53% at 12 months and 33% at 24 months. CONCLUSIONS: Based on our findings, we suggest that stiripentol is an effective and well-tolerated therapeutic option not only in Dravet syndrome but also in other epilepsy syndromes with or without an established genetic aetiology. Response duration was influenced by age at stiripentol initiation across different aetiologies

Removal of diclofenac from aqueous solutions by adsorption on thermo‑plasma expanded graphite

The adsorption of diclofenac on thermo-plasma expanded graphite (a commercial product) from water solutions was investigated. The adsorbent material was characterized by SEM, TEM, BET, Raman and X-ray diffraction analyses. Typical diffractogram and Raman spectrum of graphitic material, dimension of 24.02 nm as crystallite dimension and a surface area of 47 m2 g−1 were obtained. The effect of pH on the adsorption capacity was evaluated in the range 1–7 and the adsorption mechanism was described by kinetic and isothermal studies. Pseudo-second order and Dubinin–Radushkevich models agreed with theoretical values of adsorption capacity (i.e. 400 and 433 mg g−1, respectively) and resulted to be the best fit for kinetics and isothermal experimental data. The thermodynamics of the process was evaluated by plotting the adsorption capacity/concentration ratio at the equilibrium as a function of different values of the multiplicative inverse of temperature. Moreover, the adsorbent regeneration was also investigated, comparing two different remediation techniques. Solvent washing performed with NaOH 0.2 M and thermo-treatment carried out by heating in an oven at 105 °C for 2 h and then at 200 °C for 4 h. The thermo-treatment was the best technique to regenerate the adsorbent, ensuring same performance after 4 cycles of use and regeneration

EXPERIMENTAL ASSESSMENT OF CARBON FIBER JACKETING OF STEEL PLATES

It is presented a numerical assessment of experimental data concerning Mode–II delamination tests of steel plates jacketed with Carbon fiber textile sheets. In particular, an inverse identification procedure, based on finite element analysis, has been performed in order to estimate the constitutive parameters of the interface bonding steel and textile. Such a procedure proved to be capable of characterizing a constitutive model which reproduces with sufficient accuracy the peak load and the fracture triggering propagation of the bonding interface. The identified finite element model is accurate enough to be employed in force–based design or in structural analysis where a suitable displacement–ultimate limit state is considered. The contribution analyzes the physical interpretation of the Mode–II delamination process with particular focus on its representation by means of finite element models. In particular, a discussion about the delamination process will show the consistency of the finite element model with the physical behavior of the specimen observed during the experimental tests. Such considerations, although encouraging, introduced further issues which outlines future research directions in order to improve the identification strategy