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The production of mixed municipal waste changes due to the increase of separation rate, urbanization and other factors. The future changes in the legislation and technology development influences the way the waste is being treated. Thus the method, location and capacity of processing sites are unknown. The realization of future projects can be supported by the developing of transportation infrastructure. Such a feature may be represented by a robust transfer station grid, which can be designed to handle all possible future realizations and technological solutions (establishment of waste treatment facilities). The paper presents an approach utilising a mathematical model for the design of transfer stations. It is formulated as a multi-objective two-stage mixed-integer stochastic programming problem, where the trade-off between the environmental aspect and the economic viability is considered. The model is tested through a case study for the Czech Republic, where the waste treatment of over 6,000 municipalities is analysed. The solutions for different preferences are assessed throughout the principle called out-of-sample stability with 10,000 scenarios. The optimal decision consists of the robust transfer station grid with selected locations and their respective capacity. The particular solution with respect to the potential trade-off suggests to save 1.148 mil of travelled kilometres with only 0.77 mil EUR. The output in the form of decision support can serve possible stakeholders from the field of waste management to plan more sustainable projects. • A transfer station grid designed to handle future realizations and developments. • The efficiency of waste transport was analysed for more than 6000 municipalities. • A trade-off between environmental aspects and the economic viability was considered. • A solution suggests to save travelled 1.148 mil km with only extra 0.77 mil EUR. • Introduction. [ABSTRACT FROM AUTHOR]

This paper proposes a mathematical model and two heuristic procedures to solve the cutting stock problem with usable leftovers, relating the implications of the model with aspects considering sustainability in terms of environmental, economic and social issues. The possibility of generating leftovers that can be used or sold, reduces raw material waste during the cutting process and, consequently, increases companies’ profits. By reducing waste and increasing profits, companies can become more competitive in the market. They can also integrate environmental aspects into their operational strategies and, therefore, create a better self-image and profitability, generating more jobs and contributing to a stronger local economy. We believe that the model is more likely to be adopted by smaller companies, which generally face numerous barriers but at the same time have a significant social impact, generating income and jobs. Based on the knowledge of the authors, this is the first study that relates a cutting problem with its implications for sustainability. Computational tests were performed, and the obtained results are discussed considering the win-win approach to sustainability. [ABSTRACT FROM AUTHOR]

The amount of material entering end-of-life vehicles (ELVs) management systems all over the EU has been reduced due to increased export of used vehicles to non-EU countries. According to the latest data, only 6.23 million ELVs were processed in 2012 (e.g., 8.37 million ELVs were processed in 2009). Considering that currently 342 active vehicle recycling factories exist in the EU, as well as that in the last ten years the total processing capacity has been increased several times, it is clear that there is a serious conflict. This paper proposes a multi-stage interval-stochastic programming model for planning end-of-life vehicles allocation. The developed model is able to reflect dynamics in terms of decisions for ELV allocation from a multi-region waste management system to multiple vehicle recycling factories within a multi-period context. It is capable of incorporating multiple policies within the optimization framework. Uncertainties expressed as probability distributions and discrete intervals are effectively handled, based on a multi-layered scenario tree with a finite set of scenarios. A semi-hypothetical case study is conducted in order to demonstrate the potentials and applicability of the proposed model. Influences of parameter uncertainty on model solutions are thoroughly examined. Comprehensive analyses of various policy situations, associated with different levels of economic penalties and system failure risks, are presented. The proposed model is effective for solving difficult ELV allocation problems with uncertainties included as part of the formulation. It can help quantify the relationships between ELV management system profit and disruption risk of the vehicle recycling factories, and thus provide optimal ELV allocation schemes. [ABSTRACT FROM AUTHOR]

Abstract: Part I of this paper contained a technological description and economic evaluation of a large-scale high-end CDW recycling plant in the Lisbon Metropolitan area. It concludes that economic viability is likely under the operating conditions considered, but these may and will very probably change in the near future. The reasons for such assumption have to do with the inherent uncertainty related to CDW generation (which might vary, for instance, due to socio-economic conditions in the region), such as the variability of CDW input gate fees and tariffs associated with landfilling rejected materials, which are market dependent parameters. This made it necessary to perform an (simplified) economic viability sensitivity analysis, focused on the investment return period and global economic balance. If parameters such as the plant''s capacity, the CDW input gate fee and landfill fee are varied, the investment return period is affected in different ways, though its value is generally kept below 8 years, for parameter variations of ±30%. The analysis indicates economic performance for variations in single parameters, except for the plant''s capacity, which was considered to vary simultaneously with all others. Extreme best and worst scenarios were also tested in an attempt to define the model''s boundaries. [Copyright &y& Elsevier]

Abstract: The significance of waste management systems in recent years increased due to the growing problems of waste management chains affecting the daily lives of millions of people and the impact on the environment. Several promising approaches have been developed in the past few years. One of them is the waste management system modelling using reliability, availability, maintainability and safety software. This paper analyses and evaluates this approach. The main goal is to provide quantitative forecasts for various performance measures of waste management systems. They include availability, downtimes, number of failures, and cost. Evaluation of these measures is important for optimal decision making. The system design should both maximise the system performance leading to cleaner processing and minimise the overall cost within the allowable constraints. The effectiveness of this methodology is demonstrated through a case study. [Copyright &y& Elsevier]