民用建筑生命周期固体废弃物排放的资源环境压力

降低民用建筑生命周期固体废弃物排放带来的资源环境压力,促进经济发展逐步走上资源减量化和环境减压化的轨道,是全社会面临的共同问题。本文借用生态足迹方法和能值分析方法,构建了民用建筑生命周期各阶段固体废弃物排放的资源环境压力计算模型,并以沈阳市图书馆为例,进行了实证研究。结果表明:废弃水泥排放引起的资源环境压力分别占施工阶段生态足迹的48.56%,占使用与维护阶段生态足迹的82.78%,占拆除及废弃建材处置阶段生态足迹的56.73%;而废弃商品混凝土排放造成的资源环境压力在施工阶段生态足迹和拆除及废弃建材处置阶段生态足迹中的比例分别为31.90%和37.26%;就生命周期各阶段而言,拆除及废弃建材处置阶段固体废弃物排放的资源占用足迹最大,占总足迹的92.91%,使用与维护阶段资源占用足迹最小,占总足迹的1.06%。因此,民用建筑在生命周期各阶段削减固体废弃物排放量的重点是减少水泥和商品混凝土的用量,多开发可替代混凝土结构的钢结构或组合结构形式的民用建筑。     

Selection of an appropriate waste-to-energy conversion technology for Dhaka City,Bangladesh

Solid waste disposal poses a significant problem, as it leads to land pollution if openly dumped, water pollution if dumped in low lands and air pollution if burnt. Moreover, the scarcity of land and increase in land prices especially in Dhaka, the capital city of Bangladesh create the problems of developing new landfill sites. Realising the existing and future impacts of waste disposal issues, the analytic hierarchy process model was applied to select an appropriate Waste-to-Energy (WTE) conversion technology for household waste of Dhaka-Mirpur Cantonment area. Three alternatives, namely, anaerobic digestion, pyrolysis and plasma gasification (PG) technologies and nine criteria under three aspects (technological, environmental and financial) were chosen for comparison. The analysis revealed that PG is the most appropriate WTE conversion technology in the study area. The selected PG technology has a relatively small footprint; it can treat unsorted waste and can produce good-quality synthetic gas without generating extremely toxic by-products.     

Measurement of Fruit and Vegetable Losses in Brazil: A Case Study

This research conducted on municipal solid waste management for the first time quantified food spoilage as being 8.8% weight of all officially collected household garbage in the Brazilian city under study. The unexpected size of this waste fraction gave rise to work on the causes of waste and on its distribution over the product life cycle specific to fruit and vegetables. Waste was defined as being the combination of losses and scraps. Administrative shortcomings were identified as basic reasons for waste. At the producer and consumer ends of the cycle, negligence was shown to be the single most important problem. Fruit and vegetables deteriorate during the operations of handling, transport, packaging, storage, selling and consumption. The study detailed the occurrence of waste at all of these stages. In the medium-size Brazilian city, the total waste of fruit and vegetables was shown to amount to 16.6% weight in the marketing stage of the life cycle. At the consumer level, it was measured as 3.4% weight of all household garbage. Specific reasons for this waste were identified at the levels of producer, wholesaler and retailer. Short-term remedies were pointed out that invariably corrected deficient management procedures. It was shown that very simple administrative measures can significantly reduce the spoilage of fruit and vegetables. Long-term strategies involve the creation of sample cases for administration of the fruit and vegetables life cycle at all stages.     

A Study on The Management of Municipal Residential Solid Waste in China

As the main organic pollutant in municipal living waste , kitchen waste causes secondary pollution in the course of its being gathered and transported to the landfill by mixing with other refuse and by decomposition. This makes pollution prevention more difficult and raises the cost of landfill engineering. However, the amount of solid waste to be treated can be decreased and such pollution burden lessened by disposing of the solid waste in local municipal areas. The program in Beijing also shows that this works well with our situation in China and can accelerate marketization and public participation.     

Beijing Ministerial Declaration on Environment and Development

Abstract

As the main organic pollutant in municipal living waste, kitchen waste causes secondary pollution in the course of its being gathered and transported to the landfill by mixing with other refuse and by decomposition. This makes pollution prevention more difficult and raises the cost of landfill engineering. However, the amount of solid waste to be treated can be decreased and such pollution burden lessened by disposing of the solid waste in local municipal areas. The program in Beijing also shows that this works well with our situation in China and can accelerate marketization and public participation.     

城市废物的回收处理与利用

当前世界各国均面临着“废弃物”所造成的环境污染问题。本文列举了一些国家“废弃物”的排放以及回收利用情况,并举例说明对变废为宝的技术路线和应该采取的措施。     

Goal-based waste management strategy to reduce persistence of contaminants in leachate at municipal solid waste landfills

The required minimum 30-year post-closure care period for municipal solid waste (MSW) landfills can be shortened by reducing or eliminating of MSW components with long-terms effect in gas and leachate. The objectives of this study were to evaluate the relative persistence of landfill gas, leachate quantity, and selected leachate parameters using post-closure monitoring data from a case study landfill in south Florida. The relative persistence of selected decomposition byproducts in leachate were evaluated by both zero order and first order models based on monitoring data from the case study landfill. The analyses show that although gas and leachate production rates diminish very quickly, some contaminants remain in leachate as the decomposition process continues at a slower rate. For the case study landfill, the parameters which have been detected consistently at high concentrations (above MCL) included chloride, TDS, iron, bicarbonate, benzene, and vinyl chloride. Among these, vinyl chloride has the fastest and TDS has the slowest rate of disappearance in the landfill environment. The effect of waste diversion on persistence times of the selected persistent leachate quality parameters was evaluated. For example, a 40% reduction in the amount of plastics deposited in the landfill could reduce the monitoring time for benzene from 59 to 39 years. Zero order model underestimates the persistence times of the contaminants in leachate due to its linear nature. Shortening the monitoring times can provide significant savings for municipalities who need to continue monitoring leachate quality until the MCL levels are reached.     

Evaluation of chemical and ecotoxicological characteristics of biodegradable organic residues for application to agricultural land

The use of organic waste and compost as a source of organic matter and nutrients is a common practice to improve soil physico-chemical properties, meanwhile reducing the need for inorganic fertilisers. Official guidelines to assess sewage sludge and compost quality are mostly based on total metal content of these residues. Measurement of the total concentration of metals may be useful as a general index of contamination, but provides inadequate or little information about their bioavailability, mobility or toxicity when the organic residue is applied to the soil. However, ecotoxicity tests provide an integrated measure of bioavailability and detrimental effects of contaminants in the ecosystem. In the present study, three different types of biodegradable organic residues (BORs) have been considered: sewage sludge from municipal wastewater treatment (SS), compost from the organic fraction of unsorted municipal solid waste (MSWC), and garden waste compost (GWC). The BORs were subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn), in order to verify their suitability for land application. Water leachability was determined through the DIN 38414-S4 method, while the modified BCR sequential extraction procedure was used for metal speciation. Ecotoxicity of the BORs was studied by direct and indirect bioassays. Direct toxicity bioassays were: plant growth tests with cress (Lepidium sativum L.) and barley (Hordeum vulgare L.), and earthworm (Eisenia fetida) mortality. On the other hand, indirect exposure bioassays, with leachate from the residues, took into account: luminescent bacteria (Vibrio fischeri), seed germination (L. sativum and H. vulgare) and Daphnia magna immobilization. As far as total metal concentration is concerned, with particular reference to Zn, SS resulted neither suitable for the use in agriculture nor compatible to be disposed of as an inert material into landfill, according to the Directive 1999/31/EC. Zinc in SS was mainly present in exchangeable form (28.5%), appearing as highly bioavailable. As a consequence, SS exhibited either high ecotoxicity effects with the indirect exposure bioassays or significant mortality with the earthworm bioassay. Total content of metals in MSWC allowed its classification as "stabilised biowaste", according to 2nd draft [DG Env.A.2. Working document of Biological treatment of biowaste - 2nd draft. Directorate-General Environment, Brussels, 12th February; 2001. accessed in:http://europa.eu.int/comm/environment/waste/facts_en.htm, at 10/09/2002] while leachate, on the basis of the concentration of these contaminants, could be classified as "inert waste". This residue showed significant ecotoxicity effects with direct exposure bioassays as well as with the luminescent bacteria bioassay. However, it resulted less toxic than SS. Finally, GWC could be classified as a Class 2 compost, with no detectable toxic effects on the organisms used in the bioassays, except for the luminescent bacteria. In this case, an EC(50) of 73.0% was observed. Considering the results, the use of a battery of toxicity test in conjunction with chemical analysis should be suggested, in order to correctly assess possible environmental risks deriving from disposal or land application of biodegradable organic residues.     

垃圾块体填埋法及其应用前景

分析了垃圾排弃的现状、危害、潜在价值及现有的垃圾处理方法,提出创新垃圾处理方法势在必行。与已有的垃圾处理方法比较,垃圾块体填埋法有自己的特点,以社区为单元的垃圾源头分类投放、收集和预处理,能使垃圾实现分类化处理;通过垃圾中可回收废物的回收利用,能使垃圾最大限度资源化;通过垃圾分类粉碎、脱水、压缩成块体,使垃圾有效地减量化;经过消毒、分类堆砌有助于垃圾填埋场地的分类管理和安全监控,使垃圾处理基本无害化;回收、堆肥、焚烧、填埋,使垃圾处理综合化;填埋场的复垦与开发利用,使垃圾处理环保化。该方法的推广应用,可使垃圾处理无害化、减量化、资源化和市场化目标得以实现。     

Characterization of monitor recycling in Seattle, Washington

With the rapid growth of electronic waste (e-waste), policies that aim to effectively manage this waste stream have been introduced globally in recent years. Seattle, Washington, has been on the forefront of introducing policies to divert e-waste from the landfills and maximize recycling. With the introduction of the Take-it-Back-Network, a solid recycling infrastructure has existed in the Greater Seattle region since 2003. In 2009, the E-Cycle Washington program took into effect and now allows recyclers to offer free recycling of certain e-waste to households and small entities. Although policies to divert e-waste from the landfill to reuse and recycling is effective, there is also a need to analyze the current regional recycling infrastructure’s capacity to handle changing equipment and material quantities. This study aims to characterize the Seattle regional e-waste management capacity, with a focus on retired monitors as an example of a changing e-waste technology. We investigated waste computer monitor recycling in the Greater Seattle region, which includes the counties of King, Pierce, Snohomish, and Kitsap. Interviews were conducted on 20 collectors, 1 handler, and 2 processors to collect information on their business models, computer monitor management processes, and collection/processing quantities. Using this information, we summarize the material flows of end-of-life (EOL) cathode ray tube (CRT) and liquid crystal display (LCD) monitors in the region, both from the qualitative and quantitative perspective.     

A design for EoL approach and metrics to favour closed-loop scenarios for products

Recently, environmentally conscious design and extended producer responsibility have become key aspects for companies that need to develop products that are sustainable along their whole life cycle. Design for End of Life (EoL) is a strategy that aims to reduce landfill waste through the implementation of closed-loop product life cycles. It is important to consider disassembly and EoL scenario management as early as the design phase. For these reasons, this paper presents an approach to help designers in the evaluation and subsequent improvement in product EoL performance. The method is based on four innovative EoL indices that compare different EoL scenarios for each product component. In this way, the designer can modify the product structure or the liaisons to maximise the reuse and remanufacture of components as well as material recycling. The presented case studies confirm the validity of the approach in helping designers during the redesign phase of goods and products to reduce the quantity of materials and industrial wastes sent to landfill.     

Construction and demolition waste generation in cities in India: an integrated approach

ABSTRACT

This paper quantifies construction and demolition waste (C&DW) generation rate in Indian cities using bottom-up material flow analysis approach. A dynamic model was applied to different classes of cities in India to investigate how C&DW generation rate varies across different classes of cities. The data on construction and demolition activities in different classes of cities were estimated from information reported in secondary literature. The results show that urban areas in India generated over 150 million tonnes of C&DW in 2016, and almost 50% of waste was generated in small to medium towns. The paper concludes with discussion on opportunities for recycling of C&DW and closing the material loops in Indian cities.     

Recovery of copper from small grain size fractions of municipal solid waste incineration bottom ash by means of density separation

Small grain size fractions of municipal solid waste incineration (MSWI) bottom ash (BA) contain elemental and chemically bonded metals in appreciable amounts, especially copper. Investigations with a centrifugal concentrator were carried out using samples, which had been treated with different impact devices. Partly the impacts of single devices were visible in outlines, but mostly the surfaces of the metals were still covered with mineral residues. To generate copper rich fractions, parameters of the separation process should ensure mass yields <2%, best between 0.5 and 1%. The density of the concentrates is then generally >3.2 g/cm³. Best results were achieved with material from a special treatment train which is adapted to grain sizes <2 mm. Reliable copper contents between 20 and 40% (single runs >50%) could be realised. However, considering the required mass yields, referred to this subset only 150–170 g copper would be recovered from 1 Mg MSWI BA. Furthermore, this copper is only in parts present in elemental form. A dependable added value of such treatment step seems to be given only, if that enables a recycling of the mineral aggregates (tailings) in parallel to avoid landfill costs.     

Sustainability research and practices in enforced residential institutions: collaborations of ecologists and prisoners

Enforced institutional settings such as penitentiaries provide environments to raise awareness, carry out research, and implement and assess practices for sustainable living. Institutions where residence is enforced due to health, recreational, military, or legal reasons (e.g., assisted living centers, summer camps, army bases, prisons) house people who may lack scientific training but have time and need for intellectual stimulation that can be filled by supervised research. These institutions have stable populations, structured social organization, and measurable inputs and outputs of materials and energy to carry out sustainable practices in tasks that affect regional resources such as groundwater quality and landfill use. We report on three examples at a corrections center resulting from partnerships among visiting academic ecology researchers, sustainability practitioners, corrections administrators, and prisoners: (1) research on how to sustainably “farm” moss for the horticulture trade to reduce harvesting pressure on wild moss populations; (2) a vermiculture and thermophilic composting system to reduce the kitchen waste; and (3) a monthly seminar series at the prison. Over 26 months: (1) participants developed methods to optimize moss growth; (2) landfill-bound waste and particulate flow rate destined for wastewater treatment decreased by 50%, to less than 50% of permit limits; (3) resulting compost (ca. 5000 kg) fertilized institutional vegetable gardens; (4) water quality improved so that the prison could return funds allocated to upgrade the prison’s water quality. The lectures encouraged intellectual exchange among researchers, convicts, and guards. Researchers derived new perspectives and broader impacts for their work. This can be a model for other correctional facilities and other enforced residential institutions (ERIs). Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

The copper cycles of European countries

A comprehensive technological copper cycle treating a series of life stages (mining and processing, fabrication, utilization, and end of life) has been constructed for sixteen countries on the European continent for the year 1994. In this paper we draw on that information to present country-level copper cycles for a sampling of the countries. We then compare the countries on the basis of their relative and absolute copper production, import/export, usage, recycling, and losses to the environment, and go on to produce per capita assessments of flow and stock changes. Among the results of particular interest are: (1) country-level copper budgets possess features often different from the continental budgets of which they are a part. For example, Europe extracted only slightly more copper from mines than it deposited in landfills, while the mine to landfill flow ratio was about 11:1 in Poland and near zero in the United Kingdom; (2) Germany led all other countries in the group of sixteen in the absolute magnitude of every major copper flow (production, import, export, consumption, and waste generation, and in per capita flows of copper entering use and waste management), while the Benelux countries led all others in per capita flows for all other categories; (3) citizens of essentially all the countries discarded 1–3 kg Cu/year, mostly in obsolete electronics and end-of-life vehicles.     

A holistic approach to Concentration Assessment of hazards in the risk assessment of landfill leachate

Risk assessment is a new research area. The risk assessment research area deals with a wide range of issues other than landfills. Examples of these issues are Radiation, Food Industry, Ecology, Epidemiology, etc. The authors have found that there are generic elements in risk assessment and these elements are independent of the subject areas mentioned above. An important example of these generic elements is the Concentration Assessment of hazards and is equally important from the perspective of landfill risk assessment. Furthermore, in the literature review of landfill risk assessment approaches, no evidence has been discovered of a holistic risk assessment methodology for landfill gas, leachate, or degraded landfill waste. A range of knowledge deficiencies has been found in the literature reviewed to date. One of these deficiencies in knowledge is the lack of a holistic procedure for carrying out Concentration Assessment. From the perspective of landfill leachate, this paper discusses the extent to which the Concentration Assessment of hazards is absent in landfill risk assessment approaches described in the literature reviewed to date, and the elements that should be added to the procedure of the Concentration Assessment in order to enhance the process of risk assessment. The paper also briefly outlines a holistic procedure for the Concentration Assessment and a corresponding computer model for the risk assessment of landfill leachate.     

Environmental Optimisation in Fractionating Industrial Wastes Using Contribution Margin Analysis as a Sustainable Development Tool

This paper describes a method of estimating the “true” internal costs of industrial waste, aimed at promoting environmentally friendly waste management. The study employs contribution margin analysis and a model – The Model for Efficient Use of Resources for Optimal Production Economy (EUROPE) – introduced by the author for assigning industrial costs to waste. In a business sense, waste is regarded as having the same basic status as any normal industrial product – the equality principle. Application of the method is suggested to create incentives for environmental improvement and profitability improvement in companies. Although the results of two case studies show the generation of waste to have a substantial negative impact on the final operating income, due to the internal shadow price costs it creates, this is regarded as an unavoidable consequence of the companies' acting in accordance with the principle of sustainable development. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

完善我国医疗废物集中处置收费政策的思考和建议

医疗废物处置收费政策是医疗废物处置产业化发展的重要前提和保障。当前,医疗废物处置收费政策执行难,欠费、漏费等问题非常突出,医疗废物集中收集十分困难。在对我国医疗废物处置收费政策进行全面分析和评估的基础上,对当前收费政策存在的主要问题和产生的原因进行了分析。以加快完善医疗废物处置收费政策为目标,从完善政策体系、加强监管执法、提高标准合理性、综合确定费用承担方、制定鼓励性的经济政策、提高宣传和缴费意识等方面,提出医疗废物处置收费政策改革完善的若干建议。     

Recovery and recycling of post-consumer waste materials. Part 1. Generalities and target wastes (paper,cardboard and aluminium cans)

Recycling of post-consumer waste materials is gaining increased interest due to public awareness, legislative promotion and imposition, economic benefits and appropriate technologies being available. The present paper does not deal with municipal solid waste as such, but only with the recyclable constituents. The paper does not aim at presenting recycling process details and/or fundamental research results, but reviews the major recyclables with their reuse potential, recycling technologies used, problems, solutions and potential areas of future research and development. These target recyclables include paper and cardboard, aluminium cans, glass beverage bottles, scrap metal and steel cans, scrap tyres, batteries and household hazardous waste. The present paper sets the overall picture and deals with paper, cardboard and aluminium cans only. A second part of the paper assesses the other target recyclables. The assessment of the waste availability, the existing and currently developed recovery and recycling technologies, and the economically rewarding markets while recycling, stress the technical, economic and environmental importance of this waste management sector. The activities associated with the recovery and recycling of post-consumer wastes require a strong sustainable engineering input at all phases of the treatment, from input quality control, to the selection of the most appropriate technology and the delivery of the recyclables as readily reusable feedstock.