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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Waste heat recovery lube oil management

A waste heat recovery system comprising a thermal circuit. The thermal circuit includes a boiler and an expander fluidly coupled to the boiler. The thermal circuit further includes a power transfer system integrated to the expander. The power transfer system is configured to receive mechanical energy from the expander. The thermal circuit further includes an ejector fluidly coupled to the boiler and to the power transfer system. The ejector is configured to receive a motive flow of working fluid from the boiler. The ejector is further configured to receive a suction flow of working fluid from the power transfer system. The ejector is further configured to combine the motive flow of working fluid and the suction flow of working fluid.

Ernst, Timothy C.↗
DOE OSTI2010

Methods for Processing ENDF/B-VII with NJOY

The NJOY Nuclear Data Processing System is widely used to convert evaluations in the Evaluated Nuclear Data Files (ENDF) format into forms useful for practical applications such as fission and fusion reactor analysis, stockpile stewardship calculations, criticality safety, radiation shielding, nuclear waste management, nuclear medicine procedures, and more. This paper provides a description of the system's capabilities, summary descriptions of the methods used, and information on how to use the code to process the modern evaluated nuclear data files from ENDF/B-VII. It begins with the generation of pointwise libraries, including reaction and resonance reconstruction, Doppler broadening, radiation heating and damage, thermal scattering data, unresolved resonance data, and gas production. It then reviews the production of libraries for the continuous-energy Monte Carlo code MCNP, multigroup neutron, photon, and particle cross sections and matrices, and photon interaction data. The generation of uncertainty information for ENDF data is discussed, including new capabilities for calculating covariances of resonance data, angular distributions, energy distributions, and radioactive nuclide production. NJOY's ability to prepare thermal scattering data evaluations for bound moderators (which was used during the preparation of the ENDF/B-VII library) is described. The strong plotting capabilities of NJOY are summarized. Many examples of black and white and color Postscript plots are included throughout the paper. The capabilities of NJOY to output multigroup data in several different formats to suit various applications is reviewed. Finally, a section is included that summarizes the history of the development of the NJOY system over the last 37 years.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Tritium Packages and 17th RH Canister Categories of Transuranic Waste Stored Below Ground within Area G

A large wildfire called the Las Conchas Fire burned large areas near Los Alamos National Laboratory (LANL) in 2011 and heightened public concern and news media attention over transuranic (TRU) waste stored at LANL’s Technical Area 54 (TA-54) Area G waste management facility. The removal of TRU waste from Area G had been placed at a lower priority in budget decisions for environmental cleanup at LANL because TRU waste removal is not included in the March 2005 Compliance Order on Consent (Reference 1) that is the primary regulatory driver for environmental cleanup at LANL. The Consent Order is a settlement agreement between LANL and the New Mexico Environment Department (NMED) that contains specific requirements and schedules for cleaning up historical contamination at the LANL site. After the Las Conchas Fire, discussions were held by the U.S. Department of Energy (DOE) with the NMED on accelerating TRU waste removal from LANL and disposing it at the Waste Isolation Pilot Plant (WIPP). This report summarizes available information on the origin, configuration, and composition of the waste containers within the Tritium Packages and 17th RH Canister categories; their physical and radiological characteristics; the results of the radioassays; and potential issues in retrieval and processing of the waste containers.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

The Cires facility in Morvilliers: from a VLL waste disposal facility to the development of industrial activities - 15252

The disposal facility of CIRES for very low level wastes was designed to provide safe and cost effective services to waste generators, in particular for decommissioning works. The facility could significantly increase waste annual deliveries to meet waste generators' needs and accommodate large disused components as PWR steam generators after decontamination. However an anticipated saturation of its capacity is foreseen as needs for disposal has doubled since its start-up. The geometry of the cells was optimized and the technical capacity of the repository is presently by 40% above its licensed capacity. Saturation has been delayed; however a new facility will be necessary by 2030 and other waste management options are to be considered as recycling of metallic wastes or crushed concrete rubble. CIRES facility also became Andra's industrial platform for the management of institutional wastes. A grouping and a storage facility have been built and a new processing facility should start up in 2016. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Preliminary Evaluation of Removing SNF from Nuclear Power Plant Sites - Pilgrim Site Visit - 20048

The U.S. Department of Energy Office of Integrated Waste Management (DOE-IWM)a conducted an evaluation of removing spent nuclear fuel (SNF) from the Pilgrim site on November 4-8, 2019. The Pilgrim site is located on the western shore of Cape Cod Bay in the Town of Plymouth, Massachusetts, about 61 km southeast of Boston and 71 km east of Providence, Rhode Island. Participants in the site visit included the U.S. Department of Energy, Oak Ridge National Laboratory, Pacific Northwest National Laboratory, the state of Massachusetts, the Federal Railroad Administration, the U.S. Coast Guard, the U.S. Army Corps of Engineers, the Mashpee Wampanoag Tribe, the Consolidated Group of Tribes and Organizations, the Council of State Governments-Eastern Regional Conference, the Pilgrim Nuclear Decommissioning Citizens Advisory Panel, and the Massachusetts Coastal Railroad. The Pilgrim site was found to have two transportation mode options for the removal of SNF, offsite rail access and onsite barge access. Two offsite heavy haul truck to rail transload locations were evaluated, one in Middleborough, Massachusetts, about 35-47 km from the Pilgrim site, and a second location in Middleborough about 36-43 km from the Pilgrim site. A passenger railroad terminates in Plymouth, Massachusetts, about 11 km from the Pilgrim site; however, this location is not suitable for freight rail involving large SNF transportation casks. There is also an onsite barge facility located on the Pilgrim site that was used during construction and would require refurbishment to be used. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

Opportunities and challenges in thermochemical conversion of municipal solid waste: A comprehensive review

Recent advancements in thermochemical conversion processes have elucidated new pathways for converting municipal solid waste into valuable resources. This review explores the primary thermochemical conversion methods, including combustion, gasification, pyrolysis, torrefaction, hydrothermal carbonization, and hydrothermal liquefaction, emphasizing their potential roles in waste management and energy recovery. Key challenges including feedstock variability, ash behavior, and scale-up limitations are discussed alongside opportunities for hybrid systems and circular economy integration. A comparative analysis of research publications indicates a significant focus on thermochemical pathways within the broader context of municipal solid waste research, underscoring the growing interest in these technologies. Recent advancements in each thermochemical process, alongside their operational, technical, and economic challenges, are discussed. Comparative data reveal that torrefaction enhances the hydrophobicity and grindability of municipal solid waste components, though its energy densification benefits are more modest than those observed in biomass. Hydrothermal carbonization and liquefaction are highlighted for their ability to process high-moisture and heterogeneous waste streams. The review also synthesizes recent findings on reactor configurations, emissions control, and synergistic effects in co-processing municipal solid waste fractions. The findings underscore the importance of developing standardized protocols for municipal solid waste characterization and the need for innovative hybrid systems to improve efficiency.

99 - GENERAL AND MISCELLANEOUS↗
DOE OSTI2012

Hazard Classification of the Remote Handled Low-Level Waste Disposal Facility

The Battelle Energy Alliance (BEA) at the Idaho National Laboratory (INL) is constructing a new facility to replace remote-handled low-level radioactive waste disposal capability for INL and Naval Reactors Facility operations. Current disposal capability at the Radioactive Waste Management Complex (RWMC) will continue until the facility is full or closed for remediation (estimated at approximately fiscal year 2015). Development of a new onsite disposal facility is the highest ranked alternative and will provide RH-LLW disposal capability and will ensure continuity of operations that generate RH-LLW for the foreseeable future. As a part of establishing a safety basis for facility operations, the facility will be categorized according to DOE-STD-1027-92. This classification is important in determining the scope of analyses performed in the safety basis and will also dictate operational requirements of the completed facility. This paper discusses the issues affecting hazard classification in this nuclear facility and impacts of the final hazard categorization.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

First Road / River Barge Security Transport of SNF under the New German Transport Security Guidelines - 19102

A transfer of 342 spent fuel assemblies from NPP Obrigheim to NPP Neckarwestheim, both located alongside the river Neckar in the south of Germany, is required to promote the decommissioning process of NPP Obrigheim, which started in 2008 after the NPP had been shut down three years before. The spent fuel storage facility in Neckarwestheim offers sufficient storage space to accept the 342 SNF assemblies, stored in fifteen dry casks type CASTOR{sup R} 440/84 mvK. After several transport feasibility studies had been conducted, Daher Nuclear Technologies GmbH was awarded the commission to plan, prepare and conduct the SNF transport. Since the combined road / river barge transport promised to be the most suitable mode of transportation Daher Nuclear Technologies started to prepare its security concept, a prerequisite to apply for and attain the transport license mandatory for transporting spent nuclear fuel in Germany. In March 2014 the company applied for the transport license, which, after more than three years and numerous amendments to the security concept, was finally granted to Daher Nuclear Technologies on May 16, 2017 by the German Federal Office for the Safety of Nuclear Waste Management (successor organization of the BfS). Simultaneously to the license application phase the transport equipment - amongst others the heavy-duty trucks and trailers, the pusher tugs, the river barge and transport frames - had to be provided and modified to meet the intensified requirements of the New German Transport Security Guidelines Road / Rail as well as several other legal regulations referring to the transport of dangerous goods by road and inland waterways (e.g. ADR - European Agreement concerning the International Carriage of Dangerous Goods by Road and ADN - European Agreement concerning the International Carriage of Dangerous Goods by Inland Waterways). The planning process involved various meetings with representatives of different authorities and administrative bodies incl. accredited experts as well as subcontractors. Tremendous training efforts had to be undertaken to train more than 100 transport participants regarding security measures, health, safety and environmental measures, as well as the proper handling of radioactive material. This also included the training of the security staff, that had to be qualified in compliance with the new Transport Security Guidelines Road and Rail. Finally, in June 2017, when all preparations where complete, all requirements met, and all permits obtained, the first ever security SNF transport on a German river was performed. Three laden CASTOR{sup R} 440/84 mvK transport and storage casks were transported in one batch via heavy-duty truck-trailer from the NPP Obrigheim to the NPP's own harbor, to be rolled on to the river barge, that would carry the three casks upstream the river Neckar to the approx. fifty kilometer distant NPP Neckarwestheim. The journey on the river took about eleven hours, in which several bridges and locks had to be passed. The entire transport was escorted by qualified security staff and auxiliary police forces on waterways and alongside on roads. It attracted nationwide public attention, due to its pioneer status and the fact, that there hadn't been any SNF or HLW shipments in Germany since 2011. After the convoy safely arrived at NPP Neckarwestheim's pier the three laden CASTOR{sup R} 440/84 mvK casks were rolled off the river barge via heavy-duty truck-trailers to be stored in the on-site interim storage facility. This first transport was a success and was followed by four additionally successful security transports in September, October, November and December 2017. The public attention receded significantly during the transport campaign, which ended on December 19, 2017 with the transfer of the last three of fifteen casks to the on-site interim storage facility in Neckarwestheim. With the last cask safely transferred to the interim storage facility Daher Nuclear Technologies successfully completed the transport campaign on schedule, meeting one of EnBW's fundamental objectives to finish the transfer of the 342 SNF assemblies by the end of 2017. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

External Engagement During Evaluations of Shutdown Nuclear Power Plant Sites - 19221

This is a technical paper that does not take into account the contractual limitations under the Standard Contract for Disposal of Spent Nuclear Fuel and/or High-Level Radioactive Waste (Standard Contract) (10 CFR Part 961). Under the provisions of the Standard Contract, DOE does not consider spent nuclear fuel in multi-assembly canisters to be an acceptable waste form, absent a mutually agreed to contract amendment. To the extent discussions or recommendations in this paper conflict with the provisions of the Standard Contract, the Standard Contract provisions prevail. The U.S. Department of Energy Office of Integrated Waste Management (DOE-IWM) continues to conduct evaluations of removing spent nuclear fuel (SNF) from shutdown nuclear power plant sites. The 14 shutdown sites included in the evaluation to date have nuclear power reactors that have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The 14 shutdown sites are Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, Vermont Yankee, and Fort Calhoun. The Oyster Creek Nuclear Generating Station ceased operations in September 2018 and will be included in future evaluations. A key part of the shutdown site evaluations are visits to the sites. These site visits typically take place over 3 days. The first day is spent at the nuclear power plant site. The second day is spent evaluating the near-site transportation infrastructure, including rail infrastructure, potential heavy-haul routes, and potential rail and barge transload locations. The third day is often spent meeting with community engagement or advisory panels. External engagement activities during site visits are conducted in two areas. The first area involves inviting tribal and state representatives, State Regional Group (SRG) representatives, and Federal Railroad Administration (FRA) representatives to participate in the entire site visit. The SRG representatives are from the Southern States Energy Board, the Western Interstate Energy Board, the Council of State Governments - Midwest, or the Council of State Governments - Eastern Regional Conference, according to the location of the nuclear power plant. State representatives typically represent their state department of energy, state department of environmental or natural resources, State Rail Safety Participation Program, state police, state department of transportation, radiation protection organization, or emergency management organization. Tribal representatives explore issues associated with cultural affiliation and tribal involvement with past and present site activities. As the regulator of the U.S. railroads, the FRA representatives bring unique experience to the site visits. They also coordinate meetings with the railroads that serve the shutdown sites. The second area of external engagement activities during site visits involves meeting with local community engagement or advisory panels. Meeting with local community engagement or advisory panels provides an opportunity to inform these panels on DOE activities and the roles and responsibilities of federal agencies during site decommissioning. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Determinants of efficiency in the provision of municipal street-cleaning and refuse collection services

Effective waste management systems can make critical contributions to public health, environmental sustainability and economic development. The challenge affects every person and institution in society, and measures cannot be undertaken without data collection and a quantitative analysis approach. In this paper, the two-stage double bootstrap procedure of is used to estimate the efficiency determinants of Spanish local entities in the provision of public street-cleaning and refuse collection services. The purpose is to identify factors that influence efficiency. The final sample comprised 1072 municipalities. In the first stage, robust efficiency estimates are obtained with Data Envelopment Analysis (DEA). We apply the second stage, based on a truncated-regression, to estimate the effect of a group of environmental factors on DEA estimates. The results show the existence of a significant relation between efficiency and all the variables analysed (per capita income, urban population density, the comparative index of the importance of tourism and that of the whole economic activity). We have also considered the influence of a dummy categorical variable - the political sign of the governing party - on the efficient provision of the services under study. The results from the methodology proposed show that municipalities governed by progressive parties are more efficient.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2010

Summary of Conceptual Models and Data Needs to Support the INL Remote-Handled Low-Level Waste Disposal Facility Performance Assessment and Composite Analysis

An overview of the technical approach and data required to support development of the performance assessment, and composite analysis are presented for the remote handled low-level waste disposal facility on-site alternative being considered at Idaho National Laboratory. Previous analyses and available data that meet requirements are identified and discussed. Outstanding data and analysis needs are also identified and summarized. The on-site disposal facility is being evaluated in anticipation of the closure of the Radioactive Waste Management Complex at the INL. An assessment of facility performance and of the composite performance are required to meet the Department of Energy’s Low-Level Waste requirements (DOE Order 435.1, 2001) which stipulate that operation and closure of the disposal facility will be managed in a manner that is protective of worker and public health and safety, and the environment. The corresponding established procedures to ensure these protections are contained in DOE Manual 435.1-1, Radioactive Waste Management Manual (DOE M 435.1-1 2001). Requirements include assessment of (1) all-exposure pathways, (2) air pathway, (3) radon, and (4) groundwater pathway doses. Doses are computed from radionuclide concentrations in the environment. The performance assessment and composite analysis are being prepared to assess compliance with performance objectives and to establish limits on concentrations and inventories of radionuclides at the facility and to support specification of design, construction, operation and closure requirements. Technical objectives of the PA and CA are primarily accomplished through the development of an establish inventory, and through the use of predictive environmental transport models implementing an overarching conceptual framework. This document reviews the conceptual model, inherent assumptions, and data required to implement the conceptual model in a numerical framework. Available site-specific data and data sources are then addressed. Differences in required analyses and data are captured as outstanding data needs.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2014

Hot Cell Liners Category of Transuranic Waste Stored Below Ground within Area G

A large wildfire called the Las Conchas Fire burned large areas near Los Alamos National Laboratory (LANL) in 2011 and heightened public concern and news media attention over transuranic (TRU) waste stored at LANL’s Technical Area 54 (TA-54) Area G waste management facility. The removal of TRU waste from Area G had been placed at a lower priority in budget decisions for environmental cleanup at LANL because TRU waste removal is not included in the March 2005 Compliance Order on Consent (Reference 1) that is the primary regulatory driver for environmental cleanup at LANL. The Consent Order is an agreement between LANL and the New Mexico Environment Department (NMED) that contains specific requirements and schedules for cleaning up historical contamination at the LANL site. After the Las Conchas Fire, discussions were held by the U.S. Department of Energy (DOE) with the NMED on accelerating TRU waste removal from LANL and disposing it at the Waste Isolation Pilot Plant (WIPP). This report summarizes available information on the origin, configuration, and composition of the waste containers within the Hot Cell Liners category; their physical and radiological characteristics; the results of the radioassays; and the justification to reclassify the five containers as LLW rather than TRU waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Panel Session 16: Hot Topics and Emerging Issues in US Commercial LLRW Management and Disposal

This panel focused on emerging issues in commercial LLW management in the US from the perspective of active members of the Low-Level Radioactive Waste Forum, Inc. State, compact, federal and industry officials will share their views on a variety of timely and significant topics related to low-level radioactive waste management, disposal and related issues. Presentations proposed include: 1 - Overview of NRC Activities and Initiatives (John Tappert, US NRC (USA)); 2 - Advocates for Responsible Disposal in Texas (Edward Selig, Advocates for Responsible Disposal in Texas (ARDT) (USA)); 3 - Hot Topics and Emerging Issues in U.S. Commercial LLW Management and Disposal (Joe Weismann, US Ecology (USA)); 4 - DOE/NNSA Office of Radiological Security (ORS) Sealed Source Management and Disposal (David Martin, Energetics Incorporated (USA), Temeka Taplin, US DOE NNSA (USA))

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Panel Session 128: Best Practices in Project Communications

This panel focused on a sustainable, holistic and integrated approach to structure nuclear waste management, disposal and remediation decisions. This panel had participation from internal and external stakeholders and demonstrate use of tools and techniques to effectively communicate factors that inform decisions. The desired outcome was to effectively communicate how risk is evaluated at complex sites, highlight holistic site level approaches that are protective of human health and the environment, and incorporate policy and technical concerns related to achieving alternative end points. This discussion included existing decision-making tools in conjunction with case studies. Panelists with presentations: Removing the Cloak of Secrecy from Legacy Cleanup at Los Alamos National Laboratory (David Nickless); Best Practice In Project Communications (Alan Paulley); Stakeholder and Public Engagement (Mark Lesinski); Stakeholder Engaged Structured Decision Making (Kelly Black)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

Assessing recycling versus incineration of key materials in municipal waste: The importance of efficient energy recovery and transport distances

Highlights: Black-Right-Pointing-Pointer We model the environmental impact of recycling and incineration of household waste. Black-Right-Pointing-Pointer Recycling of paper, glass, steel and aluminium is better than incineration. Black-Right-Pointing-Pointer Recycling and incineration of cardboard and plastic can be equally good alternatives. Black-Right-Pointing-Pointer Recyclables can be transported long distances and still have environmental benefits. Black-Right-Pointing-Pointer Paper has a higher environmental benefit than recyclables found in smaller amounts. - Abstract: Recycling of materials from municipal solid waste is commonly considered to be superior to any other waste treatment alternative. For the material fractions with a significant energy content this might not be the case if the treatment alternative is a waste-to-energy plant with high energy recovery rates. The environmental impacts from recycling and from incineration of six material fractions in household waste have been compared through life cycle assessment assuming high-performance technologies for material recycling as well as for waste incineration. The results showed that there are environmental benefits when recycling paper, glass, steel and aluminium instead of incinerating it. For cardboard and plastic the results were more unclear, depending on the level of energy recovery at the incineration plant, the system boundaries chosen and which impact category was in focus. Further, the environmental impact potentials from collection, pre-treatment and transport was compared to the environmental benefit from recycling and this showed that with the right means of transport, recyclables can in most cases be transported long distances. However, the results also showed that recycling of some of the material fractions can only contribute marginally in improving the overall waste management system taking into consideration their limited content in average Danish household waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2010

Options Study - Phase II

The Options Study has been conducted for the purpose of evaluating the potential of alternative integrated nuclear fuel cycle options to favorably address the issues associated with a continuing or expanding use of nuclear power in the United States. The study produced information that can be used to inform decisions identifying potential directions for research and development on such fuel cycle options. An integrated nuclear fuel cycle option is defined in this study as including all aspects of the entire nuclear fuel cycle, from obtaining natural resources for fuel to the ultimate disposal of used nuclear fuel (UNF) or radioactive wastes. Issues such as nuclear waste management, especially the increasing inventory of used nuclear fuel, the current uncertainty about used fuel disposal, and the risk of nuclear weapons proliferation have contributed to the reluctance to expand the use of nuclear power, even though it is recognized that nuclear power is a safe and reliable method of producing electricity. In this Options Study, current, evolutionary, and revolutionary nuclear energy options were all considered, including the use of uranium and thorium, and both once-through and recycle approaches. Available information has been collected and reviewed in order to evaluate the ability of an option to clearly address the challenges associated with the current implementation and potential expansion of commercial nuclear power in the United States. This Options Study is a comprehensive consideration and review of fuel cycle and technology options, including those for disposal, and is not constrained by any limitations that may be imposed by economics, technical maturity, past policy, or speculated future conditions. This Phase II report is intended to be used in conjunction with the Phase I report, and much information in that report is not repeated here, although some information has been updated to reflect recent developments. The focus in this Options Study was to identify any nuclear fuel cycle technology or option that may result in a significant beneficial impact to the issues as compared to the current U.S. approach of once-through use of nuclear fuel in LWRs or similar reactors followed by direct disposal of UNF. This approach was taken because incremental differences may be difficult to clearly identify and justify due to the large uncertainties that can be associated with the specific causes of the issues. Phase II of this Options Study continued the review of nuclear fuel cycle options that was initiated and documented during Phase I, concentrating on reviewing and summarizing the potential of integrated nuclear fuel cycles. However, based on the reviews of previous studies and available data, it was not always possible to clearly determine sufficiently large differences between the various fuel cycle and technology options for some of the issues or evaluation measures, for example, in cases where only incremental differences with respect to the issues might be achieved regardless of the fuel cycle option or technologies being considered, or where differences were insufficient to clearly rise above the uncertainties.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2010

A competing risks approach for time estimation of household WEEE disposal

The recent growth in the number of electrical and electronic devices is viewed as one the priority waste streams in European Union waste management policy. This paper presents the findings of a survey to study domestic habits with respect to Waste Electrical and Electronic Equipment (WEEE) in Spain. A specific problem when performing this estimation arises from the fact that consumers quite often store old appliances at home when they are no longer used. Focusing on four different types of appliance, survival analysis (SA) is used to study both the usage span and the reasons for no longer using each device. The time that the discarded products were kept at home before being disposed of was studied using competing risks (CR) analysis. The results of the analysis provide information on the distribution of the studied variables for the different outcomes as well as the influence exerted by the socio-demographic variables considered. Relations between these characteristics and the storage time of the appliances before disposal emerge based on survey data. For instance, the CR model finds that the storage time of the some appliances (i.e. refrigerator) is related to these social-demographics factors. However, other appliances (i.e. microwave oven) are less influenced by these factors. The attitude and motivation of the respondents to the survey as regards the End-of-Life of appliances were also analysed. A majority of respondents do not store discarded appliances at home. The first reason for storing appliances at home is the possibility of it being useful in the future and the second that the respondents did not know what to do with them.

54 ENVIRONMENTAL SCIENCES↗