Life cycle assessment of integrated recycling schemes for plastic containers and packaging with consideration of resin composition

Many life cycle assessment studies have evaluated and compared the environmental performance of various technologies for recycling plastic containers and packaging in Japan and other countries. However, no studies have evaluated the combination of recycling technologies in consideration of the resin composition in terms of the quantity of each recycled product so as to maximize their environmental potential. In this study, 27 scenarios of recycling schemes for household waste plastic containers and packaging are developed through integrating a conventional recycling scheme with additional recycling schemes. The conventional recycling scheme involves municipal curbside collection and either the material recycling or feedstock recycling of waste plastics. The additional recycling schemes are feedstock recycling in steel works of the residue from conventional material recycling processes, and corporate voluntary collection and independent material recycling of specific types of plastic trays. Life cycle assessment based on the modeling of recycling processes considering the resin composition in terms of the quantity of each recycled product is applied to evaluate and compare these scenarios from the viewpoints of fossil resource consumption and CO₂ emission. The results show that the environmental loads are reduced in all scenarios including the additional recycling schemes compared with the conventional recycling scheme. However, the independent plastic tray recycling scheme exhibits lower additional environmental savings when the residue recycling scheme is integrated with the conventional material recycling scheme. This is because both additional recycling schemes aim to utilize polystyrene and polyethylene terephthalate, which would otherwise be incinerated as residue from material recycling processes. The evaluation of the environmental loads of plastic recycling with consideration of the resin composition in terms of the quantity of each recycled product makes it possible to investigate recycling schemes that integrate different technologies to maximize their environmental potential.     

Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input-output model: A case of Suzhou in China

Investigating impacts of urban solid waste recycling on urban metabolism contributes to sustainable urban solid waste management and urban sustainability. Using a physical input-output model and scenario analysis, urban metabolism of Suzhou in 2015 is predicted and impacts of four categories of solid waste recycling on urban metabolism are illustrated: scrap tire recycling, food waste recycling, fly ash recycling and sludge recycling. Sludge recycling has positive effects on reducing all material flows. Thus, sludge recycling for biogas is regarded as an accepted method. Moreover, technical levels of scrap tire recycling and food waste recycling should be improved to produce positive effects on reducing more material flows. Fly ash recycling for cement production has negative effects on reducing all material flows except solid wastes. Thus, other fly ash utilization methods should be exploited. In addition, the utilization and treatment of secondary wastes from food waste recycling and sludge recycling should be concerned.     

Recycling rates of waste home appliances in Taiwan

The objective of this study is to provide a calculation of recycling rates of waste home appliances in Taiwan, for the EPA to amend these rates in order to increase the recycling efficiency. The recycling rate is calculated by a formula according to the statistical results obtained through: (1) an estimation of domestic use of home appliances using time series analysis with multiplicative seasonal ARIMA model, (2) a further estimation of generated waste home appliances based upon the estimated domestic use and the corresponding distribution of lifetime span, and (3) a cost analysis of recycling home appliances based on a sampling survey with stratified systematic sampling conducted among collectors and a survey on five recycling plants of waste home appliances. The suggested recycling rates in this study finally used by the EPA show that all of the recycling rates have increased compared with the rates in previous years. This study also implies that amending the recycling rates may only solve some recycling problems temporarily; however, the recycling system of waste home appliances in Taiwan has to be reformed to increase the recycling efficiency for the long term.     

Comparisons of four categories of waste recycling in China's paper industry based on physical input-output life-cycle assessment model

Waste recycling for paper production is an important component of waste management. This study constructs a physical input-output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China’s paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for paper production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment.     

Evaluation of the effect of automotive bumper recycling by life-cycle inventory analysis

This paper describes a case study of the application of life-cycle inventory analysis to automotive bumper recycling. Two scenarios of bumper recycling are compared. One is “bumper-to-bumper recycling,” in which we recycle bumpers into more bumpers. The other is “cascade recycling,” in which bumpers are recycled into different parts of a car with a lower function. Inventory analysis is applied to both these recycling scenarios by analyzing the stages of acquiring natural resources, manufacturing materials, and parts, disposal, and recycling. We chose air emission, solid waste, and fossil fuel resources as items of the inventory analysis. We quantified the effect of reductions in the environmental load by recycling bumpers, and found that reductions in the environmental load were larger with cascade recycling than with bumper-to-bumper recycling based on current conditions. Received: February 2, 2000 / Accepted: April 21, 2000     

Life Cycle Assessment of Poly(Lactic Acid) (PLA): Comparison Between Chemical Recycling,Mechanical Recycling and Composting

This paper presents a life cycle assessment (LCA) comparing three forms of poly(lactic acid) (PLA) disposal: mechanical recycling, chemical recycling and composting. The LCA data was taken from lab scale experiments for composting and hydrolysis steps. Polymerization data in chemical recycling was obtained from computer simulation. Mechanical recycling data from lab scale were combined with the data from a plastics commercial mechanical recycling plant. The analysis considered two different product systems based on the input of the recycled PLA in the product system. Considering the categories: climate change, human toxicity and fossil depletion, the LCA showed that mechanical recycling presented the lowest environmental impact, followed by chemical recycling and composting. Among the forms of recycling, the most important input was the electricity consumption.     

关于遏制废旧铅酸蓄电池环境污染现象的建议

近几年,我国废旧铅酸蓄电池的回收处理工作取得了很大进展,但由于各种原因引起的环境污染现象仍触目惊心.回收处理废旧铅酸蓄电池提取再生铅,与原生铅相比更节能环保,符合资源回收和循环利用法则.但目前回收和处理市场很不规范,存在严重的环境污染问题,着重讨论用政策引导的方式规范废旧铅酸蓄电池回收处理市场,实现资源节约和环境保护的双重目的.     

On achieving the state's household recycling target: a case study of Northern New Jersey, USA

In recent times, the State of New Jersey (USA) has been making attempts at promoting recycling as an environmentally friendly means of attaining self-sufficiency at waste disposal, and the state has put in place a 50% recycling target for its municipal solid waste stream. While the environmental benefits of recycling are obvious, a recycling program must be cost effective to ensure its long-term sustainability. In this paper, a linear programming model is developed to examine the current state of recycling in selected counties in Northern New Jersey and assess the needs to achieve the state's recycling goal in these areas. The optimum quantities of waste to be sent to the different waste facilities, which include landfills, incinerators, transfer stations, recycling and composting plants, are determined by the model. The study shows that for these counties, the gap between the current waste practices where the recycling rate stands at 32% and the state's goal can be bridged by more efficient utilization of existing facilities and reasonable investment in expanding those for recycling activities.     

The development and prospects of the end-of-life vehicle recycling system in Taiwan

Automobiles usually contain toxic substances, such as lubricants, acid solutions and coolants. Therefore, inappropriate handling of end-of-life vehicles (ELVs) will result in environmental pollution. ELV parts, which include metallic and non-metallic substances, are increasingly gaining recycling value due to the recent global shortage of raw materials. Hence, the establishment of a proper recycling system for ELVs will not only reduce the impact on the environment during the recycling process, but it will also facilitate the effective reuse of recycled resources. Prior to 1994, the recycling of ELVs in Taiwan was performed by related operators in the industry. Since the publishing of the “End-of-life vehicle recycling guidelines” under the authority of the Waste Disposal Act by the Environmental Protection Administration (EPA) in 1994, the recycling of ELVs in Taiwan has gradually become systematic. Subsequently, the Recycling Fund Management Board (RFMB) of the EPA was established in 1998 to collect a Collection–Disposal–Treatment Fee (recycling fee) from responsible enterprises for recycling and related tasks. Since then, the recycling channels, processing equipment, and techniques for ELVs in Taiwan have gradually become established. This paper reviews the establishment of the ELV recycling system, analyzes the current system and its performance, and provides some recommendations for future development. The reduction of auto shredder residue (ASR) is a key factor in maximizing the resource recovery rate and recycling efficiency. The RFMB needs to provide strong economic incentives to further increase the recycling rate and to encourage the automobile industry to design and market greener cars.     

石家庄市农村再生资源回收体系建设的现状、存在问题及对策

石家庄市是再生资源回收体系建设试点城市,再生资源回收利用事业扎实推进,成绩显著,但石家庄市广大农村地区再生资源回收利用网络建设事业发展缓滞。分析了石家庄市农村再生资源回收体系建设的现状和存在的问题,对如何有效地推进农村再生资源回收利用事业发展,更好地促进农村生态文明和社会主义新农村建设提出建议和对策。     

Management of recycling in the Gulf Co-operation Council states

Although some of the Gulf Co-operation Council (GCC) member states have placed recycling at the top of their waste management priorities, the low cost of landfill and the availability of land, usually old sand or gravel quarries, make recycling programs infeasible, uneconomical and unachievable. The only comprehensive form of recycling available within the GCC states is recycling of paper and cartons. The majority of the GCC states never set national or regional recycling targets. The cost of recycling in the GCC states region could be moderate to high depending on the collection system selected for the recycling program. Almost all of the cities within the GCC states use mechanised systems for daily collection of municipal solid waste (MSW). Therefore, the same daily collection system used for MSW might well be used for collection of recyclable materials, both on the same day and at the same time, or according to a different timetable. This paper provides strategies for developing an effective recycling marketing program and discusses regional co-ordination options.     

上海市一次性塑料饭盒的管理现状分析及建议

梳理了上海市在一次性塑料饭盒管理工作中回收处置系统难以正常运转的主要问题，提出了建立全国一盘棋的格局，将其他塑料废弃物纳入回收处置的管理范畴，并建立对废塑料回收处置的奖励或补贴政策，从而继续控制视觉污染，促进生活垃圾减量化和资源化。     

大连实施垃圾分类回收积极推进垃圾资源再生利用产业化

大连在全国率先创建新型垃圾分类回收体系,实现废旧物资回收与垃圾分类回收在同一个垃圾分类回收站内完成,有利于各类废物资源集中收集、分类回收、资源化利用或处理,彻底改革了我国传统落后的废旧物资回收与垃圾收集处理方式,为废旧物资与垃圾资源再生与循环利用提供了保障条件,也为垃圾处理产业化奠定了坚实的基础。     

国外建筑废弃物循环利用的经验及对我国的启示

伴随着建筑废弃物产生量的迅速增长,建筑废弃物循环利用已成为循环经济发展的重点领域。从完善的法律法规、深度循环利用方式和产业化发展等方面,对国外发达国家废弃物循环利用的经验和做法加以总结和提升,并结合我国实际,提出建立健全我国建筑废弃物法律法规体系、构筑多级循环利用模式和培育废弃物利用产业体系的几点启示,以期为我国相关部门制定建筑废弃物的相关政策制度、提高建筑废弃物的循环再利用水平提供参考和依据。     

建设有中国特色的再生资源回收利用体系

分析了我国再生资源回收利用工作的现状,借鉴发达国家的先进经验,提出建设我国再生资源回收利用体系的基本框架,以及发展我国再生资源产业的政策建议。指出建设具有中国特色的再生资源回收利用体系是推动再生资源产业成为新的经济增长点的前提和保障。     

对县级供销社再生资源回收网络体系的设计与思考

目前,县级再生资源回收网络体系存在体系不健全、行业发展基础薄弱、回收企业经营管理落后、回收网点散乱、回收技术落后、回收资源范围小、再利用效率低等问题。县域经济实力增强、政策扶持和社会各界支持、资源回收利润合理,为县级供销社建设再生资源回收网络体系提供了发展机会。建立以村级回收站为基础、乡镇级分拣中心为支撑、县级再生资源集散交易市场为核心的三级再生资源回收网络体系。通过建设专业市场、鼓励龙头企业发展、强化市场监管、推进完善回收网络体系,以及政府政策规范、引导和扶持,从而推进再生资源回收网络体系建设。     

建筑废弃物循环利用的GD-AHP模型研究

通过分析国内外建筑废弃物循环利用的现状,找出制约我国建筑废弃物循环利用的因素,并借鉴国外的成功经验,提出促进我国建筑废弃物循环利用的可行方案;运用群组层次分析法（GD-AHP）分析获取的专家问卷数据,得出了可行方案的重要性排序.     

大力推进城市资源循环利用基地建设——以北京市朝阳区资源循环利用产业基地为例

资源循环利用基地的建设是破解城市固体废弃物“邻避效应”的创新道路,有助于新型城市功能区的建设,是推进资源循环利用的主要方式。以北京市朝阳区资源循环利用产业基地为例,研究其基地建设的优势基础及制约因素,通过探索基地建设模式,分析了基地建设的总体思路和重要举措,以期为其他地区资源循环利用基地建设提供经验。     

The potential of financial incentives to enhance householders' kerbside recycling behaviour

Although the successful enhancement of householders' participation in kerbside recycling schemes is essential for household waste recycling schemes to reach their desired levels of achievement, our understanding of householders' responses to the various incentives available to waste managers is incomplete. In particular, whether and how the recycling behaviour of householders may be favourably altered through imposition of financial penalties or rewards is not fully understood. Surveys of householders' attitudes in the London Borough of Havering, served by a kerbside co-mingled survival bag recycling scheme, showed they might be better encouraged to recycle more through improvements to structural and promotional aspects of the recycling scheme than through imposition of financial incentives. If financial incentives were to be imposed to enhance kerbside recycling, householders preferred: (1) rewards to penalties, and (2) community-based rewards and local taxation rebates to other or individual rewards. Given the attitudes of householders and the resources that would be needed to monitor their recycling behaviour as a basis for delivering financial incentives, it is suggested that the priority for enhancing recycling should be to make appropriate improvements in the infrastructure and support of the kerbside scheme and service.     

Cross-cultural comparison of concrete recycling decision-making and implementation in construction industry

Waste management is pressing very hard with alarming signals in construction industry. Concrete waste constituents major proportions of construction and demolition waste of 81% in Australia. To minimize concrete waste generated from construction activities, recycling concrete waste is one of the best methods to conserve the environment. This paper investigates concrete recycling implementation in construction. Japan is a leading country in recycling concrete waste, which has been implementing 98% recycling and using it for structural concrete applications. Hong Kong is developing concrete recycling programs for high-grade applications. Australia is making relatively slow progress in implementing concrete recycling in construction. Therefore, empirical studies in Australia, Hong Kong, and Japan were selected in this paper. A questionnaire survey and structured interviews were conducted. Power spectrum was used for analysis. It was found that “increasing overall business competitiveness and strategic business opportunities” was considered as the major benefit for concrete recycling from Hong Kong and Japanese respondents, while “rising concrete recycling awareness such as selecting suitable resources, techniques and training and compliance with regulations” was considered as the major benefit from Australian respondents. However, “lack of clients’ support”, “increase in management cost” and “increase in documentation workload, such as working documents, procedures and tools” were the major difficulties encountered from Australian, Hong Kong, and Japanese respondents, respectively. To improve the existing implementation, “inclusion of concrete recycling evaluation in tender appraisal” and “defining clear legal evaluation of concrete recycling” were major recommendations for Australian and Hong Kong, and Japanese respondents, respectively.