92 resultados para Waste recycling
Resumo:
This study examined the beliefs underlying people’s decision-making, from a theory of planned behaviour (TPB) framework, in the prediction of curbside household waste recycling. Community members in Brisbane, Australia (N = 148) completed a questionnaire assessing the belief based TPB measures of attitudinal beliefs (costs and benefits), normative beliefs (important referents), and control beliefs (barriers) in relation to engaging in curbside household waste recycling for a 2-week period. Two weeks later, participants completed self report measures of recycling behaviour for the previous fortnight. The results revealed that the attitudinal, normative, and control beliefs for people who performed higher and lower levels of recycling differed significantly. A regression analysis identified both normative and control beliefs as the main determinants of recycling behaviour. For normative beliefs, high level recyclers perceived more approval from referents such as partners, friends, and neighbours to recycle all eligible materials. In addition, the strong results for control beliefs indicated that barriers such as forgetfulness, lack of time, and laziness were rated as more likely to hamper optimal recycling performance for low level recyclers. These findings provide important applied information about beliefs to target in the development of future community recycling campaigns.
Resumo:
It is well known that China and India have been recycling centers of WEEE, especially printed circuit boards, and that serious environmental pollution in these countries has been generated by improper recycling methods. After the governments of China and India banned improper recycling by the informal sector, improper recycling activities spread to other places. Then, these governments changed their policies to one of promoting proper recycling by introducing a scheme, under which E-waste recycling requires a license issued by the government. In this paper, the effectiveness of that license scheme is examined by means of an economic model. It can be shown that the license scheme can work effectively only if disposers of E-waste have a responsibility to sell E-waste to license holders. Our results run counter to the idea that international E-waste trade should be banned and provide an alternative solution to the problem.
Resumo:
Construction and demolition (C&D) waste occupies the largest share of overall waste generation in many countries. However, waste management practices and outcomes may differ between countries. For instance, in Australia, C&D waste recovery is continuously improving during the last years but the amount of C&D waste increases every year, as there has been little improvement in waste avoidance and minimization. In contrast, in Germany, waste generation remains constant over many years despite the continuous economic growth. The waste recycling rate in Germany is one of the highest in the world. However, most waste recycled is from demolition work rather than from waste generated during new construction. In addition, specific laws need to be developed to further reduce landfill of non-recycled waste. Despite of the differences, C&D waste generation and recovery in both countries depend on the effectiveness of the statutory framework, which regulates their waste management practices. This is an issue in other parts of the world as well. Therefore countries can learn from each other to improve their current statutory framework for C&D waste management. By taking Germany and Australia as an example, possible measures to improve current practices of C&D waste management through better statutory tools are identified in this paper. After providing an overview of the statutory framework of both countries and their status in waste generation and recovery, a SWOT analysis is conducted to identify strengths, weaknesses, opportunities and threats of the statutory tools. Recommendations to improve the current statutory frameworks, in order to achieve less waste generation and more waste recovery in the construction industry are provided for the German and Australian government and they can also be transferred to other countries.
Resumo:
While concrete recycling is practiced worldwide, there are many unanswered questions in relation to ultrafine particle (UFP; Dp<100nm) emissions and exposure around recycling sites. In particular: (i) Does recycling produce UFPs and in what quantities? (ii) How do they disperse around the source? (iii) What impact does recycling have on ambient particle number concentrations (PNCs) and exposure? (iv) How effective are commonly used dust respirators to limit exposure? We measured size-resolved particles in the 5-560 nm range at five distances from a simulated concrete recycling source and found that: (i) the size distributions were multimodal, with up to ~93% of total PNC in the UFP size range; and (ii) dilution was a key particle transformation mechanism. UFPs showed a much slower decay rate, requiring ~62% more distance to reach 10% of their initial concentration compared with their larger counterparts. Compared with typical urban exposure during car journeys, exposure decay profiles showed up to ~5 times higher respiratory deposition within 10 m of the source. Dust respirators were found to remove half of total PNC; however the removal factor for UFPs was only ~57% of that observed in the 100-560 nm size range. These findings highlight a need for developing an understanding of the nature of the particles as well as for better control measures to limit UFP exposure.
Resumo:
Background The population exposed to potentially hazardous substances through inappropriate and unsafe management practices related to disposal and recycling of end-of-life electrical and electronic equipment, collectively known as e-waste, is increasing. We aimed to summarise the evidence for the association between such exposures and adverse health outcomes. Methods We systematically searched five electronic databases (PubMed, Embase, Web of Science, PsycNET, and CINAHL) for studies assessing the association between exposure to e-waste and outcomes related to mental health and neurodevelopment, physical health, education, and violence and criminal behaviour, from Jan 1, 1965, to Dec 17, 2012, and yielded 2274 records. Of the 165 full-text articles assessed for eligibility, we excluded a further 142, resulting in the inclusion of 23 published epidemiological studies that met the predetermined criteria. All studies were from southeast China. We assessed evidence of a causal association between exposure to e-waste and health outcomes within the Bradford Hill framework. Findings We recorded plausible outcomes associated with exposure to e-waste including change in thyroid function, changes in cellular expression and function, adverse neonatal outcomes, changes in temperament and behaviour, and decreased lung function. Boys aged 8–9 years living in an e-waste recycling town had a lower forced vital capacity than did those living in a control town. Significant negative correlations between blood chromium concentrations and forced vital capacity in children aged 11 and 13 years were also reported. Findings from most studies showed increases in spontaneous abortions, stillbirths, and premature births, and reduced birthweights and birth lengths associated with exposure to e-waste. People living in e-waste recycling towns or working in e-waste recycling had evidence of greater DNA damage than did those living in control towns. Studies of the effects of exposure to e-waste on thyroid function were not consistent. One study related exposure to e-waste and waste electrical and electronic equipment to educational outcomes. Interpretation Although data suggest that exposure to e-waste is harmful to health, more well designed epidemiological investigations in vulnerable populations, especially pregnant women and children, are needed to confirm these associations. Funding Children's Health and Environment Program, Queensland Children's Medical Research Institute, The University of Queensland, Australia.
Resumo:
Lead is present everywhere in the environment and has been defined as one of the greatest threats to the human health. In this paper, attempts have been made to study a way of recycling the lead produced from waste usage and disposed of in such a way as to avoid degrading the surrounding environment. In order to contain the waste, recycled asphalt material is mixed with the lead and then heated with microwave energy. This is an attempt to solidify and reduce the lead contaminants and use the final product as sub-base material in road pavement construction. The microwave heating of the specimens is carried out with 30%, 50%, 80% and 100% of power at 800W. The optimum power mode is used to compare with the conventional heating of asphalt with sulfur additive. The results are characterized by compact density, permeability, and subjected to toxicity test with regards to lead concentration. A mechanical test to evaluate the stability is also performed on the three methods of solidification and to prove that microwave zapping method allow to convert into an environmentally stable material for recycling without having to be deposited in a landfill site.
Resumo:
In recent years considerable effort has gone into quantifying the reuse and recycling potential of waste generated by residential construction. Unfortunately less information is available for the commercial refurbishment sector. It is hypothesised that significant economic and environmental benefit can be derived from closer monitoring of the commercial construction waste stream. With the aim of assessing these benefits, the authors are involved in ongoing case studies to record both current standard practice and the most effective means of improving the eco-efficiency of materials use in office building refurbishments. This paper focuses on the issues involved in developing methods for obtaining the necessary information on better waste management practices and establishing benchmark indicators. The need to create databases to establish benchmarks of waste minimisation best practice in commercial construction is stressed. Further research will monitor the delivery of case study projects and the levels of reuse and recycling achieved in directly quantifiable ways
Resumo:
The refurbishment of commercial buildings is growing as a percentage of overall construction activity in Australia and this trend is likely to continue. Refurbishment generates a significant waste stream much of which is potentially reusable or recyclable. Despite this potential, several factors are known to unnecessarily inhibit the amount of recycling that actually occurs on renovation projects. In order to identify the reasons causing this reluctance, a process of project monitoring and expert consultation was carried out. Twenty three experts experienced in commercial refurbishment projects and three waste contractors with specific knowledge of construction waste were interviewed. Records of receipts for waste from a case study project reveal three principal factors inhibiting recycling rates: the presence of asbestos in the building; the continued occupation of the building during construction; and the breaking up of a large project into small separate contracts thereby reducing economies of scale. To ascertain the potential for improvement, current rates for reuse and recycling of materials were collected from the experts. The results revealed a considerable variation in practice between companies and indicated key areas which should be targeted to improve performance.
Resumo:
Renovation and refurbishment of the existing commercial building stock is a growing area of total construction activity and a significant generator of waste sent to landfill in Australia. A written waste management plan (WMP) is a widespread regulatory requirement for commercial office redevelopment projects. There is little evidence, however, that WMPs actually increase the quantity of waste that is ultimately diverted from landfill. Some reports indicate an absence of any formal verification or monitoring process by regulators to assess the efficacy of the plans. In order to gauge the extent of the problem a survey was conducted of twenty four consultants and practitioners involved in commercial office building refurbishment projects to determine the state of current practice with regard to WMPs and to elicit suggestions with regard to ways of making the process more effective. Considerable variation in commitment to recycling policies was encountered indicating a need to revisit waste minimisation practices if the environmental performance of refurbishment projects is to be improved.
Resumo:
Office building retrofit projects face many challenges for on-site waste management. While the projects themselves have the potential for a significant level of reuse and recycling from decon-struction and demolition, their unique characteristics often prohibit direct application of existing waste management systems, which are typically based on managing waste generated through new material application in new build projects. Moreover, current waste management plans include no stimuli to involve Small and Medium Enterprises (SMEs) for on-site waste management. As SMEs carry out the majority of on-site work as subcontractors, their active involvements will result in more proactive approaches to waste management and enhance project delivery. This paper discusses the interim results of a continuing research aimed at engaging SMEs in the planning processes of waste management through the collaboration between subcontractors and main contractors of retrofitting projects. It introduces a conceptual model for SMEs to proactively plan and manage on-site waste generation for both deconstruction and construction stages, before traditional waste management plans by the main contractor come into place. The model also suggests a collaboration process between SMEs as subcontractors and large companies as the main contractor to improve the involvement and performance of SMEs in waste management of office building retrofit projects.
Resumo:
Office building retrofit is a sector being highlighted in Australia because of the mature office building market characterised by a large proportion of ageing properties. The increasing number of office building retrofit projects strengthens the need for waste management. Retrofit projects possess unique characteristics in comparison to traditional demolition and new builds such as partial operation of buildings, constrained site spaces and limited access to as-build information. Waste management activities in retrofit projects can be influenced by issues that are different from traditional construction and demolition projects. However, previous research on building retrofit projects has not provided an understanding of the critical issues affecting waste management. This research identifies the critical factors which influence the management of waste in office building retrofit projects through a literature study and a questionnaire survey to industry practitioners. Statistical analysis on a range of potential waste issues reveals the critical factors, as agreed upon by survey respondents in consideration of their different professional responsibilities and work natures. The factors are grouped into five dimensions, comprising industry culture, organisational support and incentive, existing building information, design, and project delivery process. The discussions of the dimensions indicate that the waste management factors of office building retrofit projects are further intensified compared to those for general demolition and construction because retrofit projects involve existing buildings which are partially operating with constrained work space and limited building information. Recommendations for improving waste management in office building retrofit projects are generalised such as waste planning, auditing and assessment in the planning and designing stage, collaboration and coordination of various stakeholders and different specialists, optimised building surveying and BIM technologies for waste analysis, and new design strategies for waste prevention.
Resumo:
This paper examines factors that affect the trade of recyclable waste in both exporting and importing countries. To this end, we employ two important elements: first, we adopt a gravity model in our empirical methodology; second, we select five waste and scrap commodities and undertake estimations using commodity-level trade data. We demonstrate that, the higher the wage/per capita GDP/population of an importing country, the more recyclable wastes it imports. This result suggests that the demand for final goods and, accordingly, the demand for materials including recycled material, have strong effects on the import volume of recyclable waste. Moreover, this implies that the imports of a developing country from developed countries increase with expanding industrial activity and economic growth. We find no evidence for a pollution haven for wastes and recycling.
Resumo:
Textile waste is a significant contributor to landfill yet the majority of textiles can be recycled, allowing for the energy and fibre to be reclaimed. This chapter examines the open-loop and closed loop recycling of textile products with particular reference to the fashion and apparel context. It describes the fibres used within apparel, the current mechanical and chemical methods for textile recycling, LCA findings for each method, and applications within apparel for each. Barriers for more effective recycling include ease of integration into existing textile and apparel design methods as well as coordinated collection of post-consumer waste. The chapter concludes with a discussion of innovations that point to future trends in both open-loop and closed-loop recycling within the apparel industry.