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Abstract: The primary goal of managing MSW incineration residues is to avoid any impact on human health or the environment. Incineration residues consist of bottom ash, which is generally considered as rather harmless and fly ash which usually contains compounds which are potentially harmful for public health. Small quantities of ash (both bottom and fly) are produced currently in Greece, mainly from the healthcare waste incineration facility in Attica region. Once incineration plants for MSW (currently under planning) are constructed in Greece, the produced ash quantities will increase highly. Thus, it is necessary to organize, already at this stage, a roadmap towards disposal/recovery methods of these ash quantities expected. Certain methods, related to the treatment of the future generated ash which are more appropriate to be implemented in Greece are highlighted in the present paper. The performed analysis offers a waste management approach, having 2016 as a reference year for two different incineration rates; 30% and 100% of the remaining MSW after recycling process. The results focus on the two greater regions of Greece: Attica and Central Macedonia. The quantity of potential future ash generation ranges from 137 to 459kt for Attica region and from 62 to 207kt for central Macedonia region depending on the incineration rate applied. Three alternative scenarios for the treatment of each kind of ash are compiled and analysed. Metal recovery and reuse as an aggregate in concrete construction proved to be the most advantageous -in terms of economy-bottom ash management scenario. Concerning management of the fly ash, chemical treatment with phosphoric solution addition results to be the lowest total treatment cost and is considered as the most profitable solution. The proposed methodology constitutes a safe calculation model for operators of MSW incineration plants regardless of the region or country they are located in. [Copyright &y& Elsevier]

Abstract: A non-stoichiometric model for a downdraft gasifier was developed in order to simulate the overall gasification process. Mass and energy balances of the gasifier were calculated and the composition of produced syngas was predicted. The capacity of the modeled gasifier was assumed to be 0.5MW, with an Equivalence Ratio (EQ) of 0.45. The model incorporates the chemical reactions and species involved, while it starts by selecting all species containing C, H, and O, or any other dominant elements. Olive wood, miscanthus and cardoon were tested in the formulated model for a temperature range of 800–1200°C, in order to examine the syngas composition and the moisture impact on the supplied fuel. Model results were then used in order to design an olive wood gasification reactor. [Copyright &y& Elsevier]

Abstract: The development of renewable energy sources has clearly emerged as a promising policy towards enhancing the fragile global energy system with its limited fossil fuel resources, as well as for reducing the related environmental problems. In this context, waste biomass utilization has emerged as a viable alternative for energy production, encompassing a wide range of potential thermochemical, physicochemical and bio-chemical processes. Two significant bottlenecks that hinder the increased biomass utilization for energy production are the cost and complexity of its logistics operations. In this manuscript, we present a critical synthesis of the relative state-of-the-art literature as this applies to all stakeholders involved in the design and management of waste biomass supply chains (WBSCs). We begin by presenting the generic system components and then the unique characteristics of WBSCs that differentiate them from traditional supply chains. We proceed by discussing state-of-the-art energy conversion technologies along with the resulting classification of all relevant literature. We then recognize the natural hierarchy of the decision-making process for the design and planning of WBSCs and provide a taxonomy of all research efforts as these are mapped on the relevant strategic, tactical and operational levels of the hierarchy. Our critical synthesis demonstrates that biomass-to-energy production is a rapidly evolving research field focusing mainly on biomass-to-energy production technologies. However, very few studies address the critical supply chain management issues, and the ones that do that, focus mainly on (i) the assessment of the potential biomass and (ii) the allocation of biomass collection sites and energy production facilities. Our analysis further allows for the identification of gaps and overlaps in the existing literature, as well as of critical future research areas. [Copyright &y& Elsevier]

Abstract: In the present study, the quantities of infectious medical wastes, generated from 12 public hospitals supervised by the 2nd Health Region Administration of Central Macedonia, Northern Greece, were calculated at a very disaggregated level for the first time and were compared to other reported characterization studies. Data was recorded by using an appropriately designed questionnaire, which was completed for each day of one week, in every department, clinic, unit or laboratory of each one of the 12 aforementioned hospitals. Afterwards, average generation indexes were determined in relation to certain important organizational and functional factors, such as the number of beds, bed coverage, the different hospital sections and wards, and the type of hospital. The way that sources of infectious wastes, generated from hospitals, vary by ward and department, was also illustrated and the most important sources were identified. Generated infectious hospital wastes vary from 0.26 to 0.89kg/bed/day or 0.51 to 1.22kg/patient/day, excluding the three specialised hospitals of the Health Region. The total amount of medical waste generated from the 2nd Health Region (only public hospitals) was estimated to be 691tonnes/yr or 0.73kg/cap/yr. [Copyright &y& Elsevier]

Abstract: In Greece more than 14,000tonnes of infectious hospital waste are produced yearly; a significant part of it is still mismanaged. Only one off-site licensed incineration facility for hospital wastes is in operation, with the remaining of the market covered by various hydroclave and autoclave units, whereas numerous problems are still generally encountered regarding waste segregation, collection, transportation and management, as well as often excessive entailed costs. Everyday practices still include dumping the majority of solid hospital waste into household disposal sites and landfills after sterilization, still largely without any preceding recycling and separation steps. Discussed in the present paper are the implemented and future treatment practices of infectious hospital wastes in Central Macedonia; produced quantities are reviewed, actual treatment costs are addressed critically, whereas the overall situation in Greece is discussed. Moreover, thermal treatment processes that could be applied for the treatment of infectious hospital wastes in the region are assessed via the multi-criteria decision method Analytic Hierarchy Process. Furthermore, a sensitivity analysis was performed and the analysis demonstrated that a centralized autoclave or hydroclave plant near Thessaloniki is the best performing option, depending however on the selection and weighing of criteria of the multi-criteria process. Moreover the study found that a common treatment option for the treatment of all infectious hospital wastes produced in the Region of Central Macedonia, could offer cost and environmental benefits. In general the multi-criteria decision method, as well as the conclusions and remarks of this study can be used as a basis for future planning and anticipation of the needs for investments in the area of medical waste management. [Copyright &y& Elsevier]

The present position paper addresses contemporary waste management options, weaknesses and opportunities faced by Hellenic local authorities. It focuses on state-of-the-art, tested as well as innovative, environmental management tools on a municipal scale and identifies a range of different collaboration schemes between local authorities and related service providers. Currently, a policy implementation gap is still experienced among Hellenic local authorities; it appears that administration at the local level is inadequate to manage and implement many of the general policies proposed; identify, collect, monitor and assess relevant data; and safeguard efficient and effective implementation of MSWM practices in the framework of integrated environmental management as well. This shortfall is partly due to the decentralisation of waste management issues to local authorities without a parallel substantial budgetary and capacity support, thus resulting in local activity remaining often disoriented and isolated from national strategies, therefore yielding significant planning and implementation problems and delays against pressing issues at hand as well as loss or poor use of available funds. This paper develops a systemic approach for MSWM at both the household and the non-household level, summarizes state-of-the-art available tools and compiles a set of guidelines for developing waste management master plans at the municipal level. It aims to provide a framework in the MSWM field for municipalities in Greece as well as other countries facing similar problems under often comparable socioeconomic settings. [Copyright &y& Elsevier]

Abstract: In the present paper, implementation scenarios of a Pay-As-You-Throw program were developed and analyzed for the first time in Greece. Firstly, the necessary steps for implementing a Pay-As-You-Throw program were determined. A database was developed for the needs of the full cost accounting method, where all fınancial and waste-production data were inserted, in order to calculate the unit price of charging for four different implementation scenarios of the “polluter-pays” principle. For each scenario, the input in waste management cost was estimated, as well as the total waste charges for households. Finally, a comparative analysis of the results was performed. [Copyright &y& Elsevier]

Abstract: This paper presents the results from an analysis of municipal charges in Greece, as the fees paid by municipal waste producers to the municipal authorities are included in these charges and constitute a major part of them. The aim is to determine whether and how some of the demographic characteristics of a municipality influence the formulation of municipal waste charges and specifically the level of the charge. The study included 339 Hellenic municipalities, which comprised approximately 62% of the overall population in the country. [Copyright &y& Elsevier]

Abstract: The main aim of this study is the integrated assessment of a proposed Waste-to-Energy facility that could contribute in the Municipal Solid Waste Management system of the Region of Central Greece. In the context of this paper alternative transfer schemes for supplying the candidate facility were assessed considering local conditions and economical criteria. A mixed-integer linear programming model was applied for the determination of optimum locations of Transfer Stations for an efficient supplying chain between the waste producers and the Waste-to-Energy facility. Moreover different Regional Waste Management Scenarios were assessed against multiple criteria, via the Multi Criteria Decision Making method ELECTRE III. The chosen criteria were total cost, Biodegradable Municipal Waste diversion from landfill, energy recovery and Greenhouse Gas emissions and the analysis demonstrated that a Waste Management Scenario based on a Waste-to-Energy plant with an adjacent landfill for disposal of the residues would be the best performing option for the Region, depending however on the priorities of the decision makers. In addition the study demonstrated that efficient planning is necessary and the case of three sanitary landfills operating in parallel with the WtE plant in the study area should be avoided. Moreover alternative cases of energy recovery of the candidate Waste-to-Energy facility were evaluated against the requirements of the new European Commission Directive on waste in order for the facility to be recognized as recovery operation. The latter issue is of high significance and the decision makers in European Union countries should take it into account from now on, in order to plan and implement facilities that recover energy efficiently. Finally a sensitivity check was performed in order to evaluate the effects of increased recycling rate, on the calorific value of treated Municipal Solid Waste and the gate fee of the candidate plant and found that increased recycling efforts would not diminish the potential for incineration with energy recovery from waste and neither would have adverse impacts on the gate fee of the Waste-to-Energy plant. In general, the study highlighted the need for efficient planning in solid waste management, by taking into account multiple criteria and parameters and utilizing relevant tools and methodologies into this context. [Copyright &y& Elsevier]

Abstract: In the municipality of Thessaloniki in 2006 mercury-bearing dental wastes were not managed properly by 80% of dentists and metal-bearing waste was handled in accordance with internationally established best management practices by less than 50% of dentists. Those results were documented through a biennial field-based research study that took place in private dental units within the Thessaloniki Urban Area. For quantifying the waste produced, structured questionnaires were used and interviews with dentists were performed. In the present work, results of this survey are presented; critical parameters and factors affecting the quantity and quality of the dental waste stream are reported together with the analysis and classification of dominant conditions and needs of the dental sector in the waste management field. [Copyright &y& Elsevier]

Abstract: This paper presents a decision support tool for manufacturers and recyclers towards end-of-life strategies for waste electrical and electronic equipment. A mathematical formulation based on the cost benefit analysis concept is herein analytically described in order to determine the parts and/or components of an obsolete product that should be either non-destructively recovered for reuse or be recycled. The framework optimally determines the depth of disassembly for a given product, taking into account economic considerations. On this basis, it embeds all relevant cost elements to be included in the decision-making process, such as recovered materials and (depreciated) parts/components, labor costs, energy consumption, equipment depreciation, quality control and warehousing. This tool can be part of the strategic decision-making process in order to maximize profitability or minimize end-of-life management costs. A case study to demonstrate the models’ applicability is presented for a typical electronic product in terms of structure and material composition. Taking into account the market values of the pilot product’s components, the manual disassembly is proven profitable with the marginal revenues from recovered reusable materials to be estimated at 2.93–23.06 €, depending on the level of disassembly. [Copyright &y& Elsevier]

This paper deals with the creation of appropriate conditions aimed at developing social services for reuse and recycling of waste electrical and electronic equipment (WEEE), by the inclusion of handicapped and Roma people in the workforce. Application areas for the project are the Hellenic (Greek) regions of Thessaly and North Aegean, where these groups suffer from professional and social exclusion. The efforts to reduce unemployment in the two aforementioned groups, together with the efforts to implement related Greek and European legislation for sustainable WEEE management, are examined here. Furthermore, networking and cooperation at local, regional and central levels between small enterprises, entrepreneurships and local authorities are examined, so that these social enterprises and their corresponding investments may support the development of the Greek alternative WEEE recycling system. [Copyright &y& Elsevier]