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This paper presents a new non-parametric methodology in which robust frontiers are used to measure the impact of environmental constraints on efficiency. In this approach, a data panel structure is applied to determine which management forms for the delivery of municipal services - public or private, in cooperation or individual - are best suited to the environment where the services are provided. The study method proposed is then applied to analyse the waste collection service provided in Spanish municipalities during the period 2002-2014. The results obtained show that of the management forms considered inter-municipal cooperation adapts best to heterogeneous environmental conditions.In the Western hemisphere, the hybridity of public service delivery is widely acknowledged to generate governance challenges arising from the mutual contestation of the competing institutional logics, such as those of the public and the private for-profit sector. The present paper explores these challenges by means of an in-depth qualitative case study of the waste management service delivery in the municipality of Znojmo, Czech Republic. Encompassing structured interviews of stakeholders and desk research, the case study was aimed at understanding the strengths and weaknesses of waste management hybridity, as well as the impact of hybridity on the relationship between innovativeness and accountability. The overall finding is that the engagement of the private for-profit sector does make this service delivery more innovative, but the useful impact of innovativeness is maximized through a hybrid arrangement. The key benefit of the hybrid arrangement is the stable intersectoral partnership allowing comprehensive control of the waste management service delivery. This benefit possibly rests on the accountability of the hybrid arrangement running on political rather than purely economic lines. Another finding was that the profit maximizing imperative was felt to constrain potential innovation, an outcome that could be prevented by the engagement of the municipality. At the same time, the hybrid mode of waste management service delivery in Znojmo is by no means free of governance challenges, such as the occasional lack of transparency and communication difficulties and disagreements among stakeholders.Solid recovered fuel (SRF) ash consists of element oxides, which are valuable materials for cement manufacturers. When SRF is co-processed in the cement industry, its mineral content is incorporated into the clinker. Therefore, from a technical perspective, SRF ash is recycled. However, since recycling processes for materials that may be present in SRF exist, and since recycling goals are defined for different waste types, understanding the origin of these ash constituents and the contribution of different materials to the Recycling-index (R-index, i.e., the material-recyclable share of SRF) is important. In this work, the origins of Al, Ca, Fe, Si, Ti, Mg, Na, K, S, and P were first reviewed. Subsequently, ten SRF samples were sorted, and the ash content and composition of the sorting fractions (e.g., less then 10 mm, plastics, paper&cardboard) determined. Additionally, selected samples of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), liquid packaging board (LPB), wood, and paper&cardboard (P&C) extracted from SRF were investigated. The results demonstrated that the materials that contributed most of the valuable oxides and ash content, and thereby to the R-index of SRF, are mixed or composite fractions, for example, the fine fraction, composites, and the sorting residues. Except for the composite LPB, no other material recovery options exist for most of these fractions. For this reason, the recycling of mixed and soiled materials or residues in the cement industry may be considered a complementary option to existing recycling processes.Pyrolysis is a waste conversion technology to solve an increasing plastic waste issue worldwide. Waste plastic pyrolysis fuel from a commercial-scale pyrolysis plant (10 ton/day) was comprehensively investigated using distillation methods by separating the crude pyrolysis fuel to isolate the diesel-like pyrolysis fuel fraction (C9-C25 for fraction 2 + fraction 3, middle distillate). Other fractions were C5-C10 for the light distillate (fraction 1), and >C25 for the heavy distillate (fraction 4). The relationship between the fuel boiling point and liquid vapor temperature were found for designing a scaled-up oil separation process. The diesel grade pyrolysis fuel fraction comprised approximately 70-80% of the crude pyrolysis fuel, wherein it had values of 43-45 MJ/kg, 1-6 cSt, and 12-42 mgKOH/goil. Meanwhile, the elemental ratios of the crude pyrolysis oil improved to 0.1 for O/C and 1.9 for H/C after separation, close to petroleum fuels (0.0 O/C and 1.95 H/C). The highest relative chemical composition was the olefins (46% in fraction 1 and 41% in fraction 2), whereas the paraffin was approximately 15-20% in the light fraction. Finally, the potential CO2 reduction for the plastic waste-to-energy process was evaluated, revealing that a total of 0.26 tCO2/tonwaste of emissions could be avoided during the waste plastic pyrolysis process.Biochar aging is a key factor leading to the decline of biochar stability and the release of endogenous pollutants. This study investigated the effects of five artificial and simulated aging processes on the surface properties and endogenous copper (Cu) and zinc (Zn) leachability of swine manure biochar and its composite with alkali-fused fly ash. Aging obviously reduced carbon (C) content on the surface of swine manure biochar and increased oxygen (O) content. Among all the aging treatments, high-temperature aging had the greatest effect on C content. Following the aging treatments, the C-C bond contents on the surfaces of swine manure biochar decreased significantly, whereas the C-O bonds increased significantly; however, there were less changes in the amounts of C-C and C-O bonds on the surfaces of modified biochar than on swine manure biochar. 4-MU Aging significantly enhanced the leaching toxicity of Cu and Zn, and Zn availability and bioaccessibility in swine manure biochar and modified biochar. However, it minimized Cu availability and bioaccessibility, especially under high-temperature aging.