Improving the layout of recycling centres by use of lean production principles

There has been increased focus on recycling in Sweden during recent years. This focus can be attributed to external environmental factors such as tougher legislation, but also to the potential gains for raw materials suppliers. Recycling centres are important components in the Swedish total recycling system. Recycling centres are manned facilities for waste collection where visitors can bring, sort and discard worn products as well as large-sized, hazardous, and electrical waste. The aim of this paper was to identify and describe the main flows and layout types at Swedish recycling centres. The aim was also to adapt and apply production theory for designing and managing recycling centre operations. More specifically, this means using lean production principles to help develop guidelines for recycling centre design and efficient control.Empirical data for this research was primarily collected through interviews and questionnaires among both visitors and employees at 16 Swedish recycling centres. Furthermore, adapted observation protocols have been used in order to explore visitor activities. There was also close collaboration with a local recycling centre company, which shared their layout experiences with the researchers in this project.The recycling centres studied had a variety of problems such as queues of visitors, overloading of material and improper sorting. The study shows that in order to decrease the problems, the recycling centres should be designed and managed according to lean production principles, i.e. through choosing more suitable layout choices with visible and linear flows, providing better visitor information, and providing suitable technical equipment. Improvements can be achieved through proper planning of the layout and control of the flow of vehicles, with the result of increased efficiency and capacity, shorter visits, and cleaner waste fractions. The benefits of a lean production mindset include increased visitor capacity, waste flexibility, improved sorting quality, shorter time for visits and improved working conditions.     

Evaluation of investments in recycling centres for construction and demolition wastes in Brazilian municipalities

There are very few construction and demolition (C&D) waste recycling centres in Brazil. To encourage the building and operation of new units, data were collected and analysed relating to C&D waste management and recycling in Brazil. Based on the results of this analysis, a conceptual model is presented for conducting viability studies of future C&D waste recycling centres. Applying this model to verify the viability of private recycling centres, the results show that under current market conditions in Brazil, C&D waste recycling centres are not financially feasible based solely on revenue from the sale of processed products. Nevertheless, under the same market conditions, the recycling centres could be economically viable for public authorities depending on the particular circumstances of each municipality. The feasibility, however, depends on continuity and the production volume reached. The conceptual model, the results of its applications and the discussions about the experiences of existing centres can strongly support public authorities and private initiatives in their decision-making about investments in Brazil and in other developing countries.     

Waste collection systems for recyclables: An environmental and economic assessment for the municipality of Aarhus (Denmark)

Recycling of paper and glass from household waste is an integrated part of waste management in Denmark, however, increased recycling is a legislative target. The questions are: how much more can the recycling rate be increased through improvements of collection schemes when organisational and technical limitations are respected, and what will the environmental and economic consequences be? This was investigated in a case study of a municipal waste management system. Five scenarios with alternative collection systems for recyclables (paper, glass, metal and plastic packaging) were assessed by means of a life cycle assessment and an assessment of the municipality’s costs. Kerbside collection would provide the highest recycling rate, 31% compared to 25% in the baseline scenario, but bring schemes with drop-off containers would also be a reasonable solution. Collection of recyclables at recycling centres was not recommendable because the recycling rate would decrease to 20%. In general, the results showed that enhancing recycling and avoiding incineration was recommendable because the environmental performance was improved in several impact categories. The municipal costs for collection and treatment of waste were reduced with increasing recycling, mainly because the high cost for incineration was avoided. However, solutions for mitigation of air pollution caused by increased collection and transport should be sought.     

Property-close source separation of hazardous waste and waste electrical and electronic equipment--a Swedish case study

Through an agreement with EEE producers, Swedish municipalities are responsible for collection of hazardous waste and waste electrical and electronic equipment (WEEE). In most Swedish municipalities, collection of these waste fractions is concentrated to waste recycling centres where households can source-separate and deposit hazardous waste and WEEE free of charge. However, the centres are often located on the outskirts of city centres and cars are needed in order to use the facilities in most cases. A full-scale experiment was performed in a residential area in southern Sweden to evaluate effects of a system for property-close source separation of hazardous waste and WEEE. After the system was introduced, results show a clear reduction in the amount of hazardous waste and WEEE disposed of incorrectly amongst residual waste or dry recyclables. The systems resulted in a source separation ratio of 70 wt% for hazardous waste and 76 wt% in the case of WEEE. Results show that households in the study area were willing to increase source separation of hazardous waste and WEEE when accessibility was improved and that this and similar collection systems can play an important role in building up increasingly sustainable solid waste management systems.     

Modelling a recovery network for WEEE: a case study in Portugal

The European Union directive for electric and electronic waste, published in 2003, enforced all European countries to meet some targets concerning the recycling and recovery of these products. This directive was transposed to the Portuguese legislation in 2004. Following this, a group of EEE producers set up an organization (Amb3e) whose mission was to design and manage a nationwide recovery network for WEEE, which will be the subject matter of this work. A generic MILP model is proposed to represent this network, which is applied to its design and planning, where the best locations for collection and sorting centres are chosen simultaneously with the definition of a tactical network planning. Several analyses are performed to provide further insights regarding the selection of these alternative locations. The results gave support to the company strategic expansion plans for a high number of centres to be opened and to their location near the major WEEE sources.     

Solid waste management practices and review of recovery and recycling operations in Turkey

This paper provides a general overview of solid waste data and management practices employed in Turkey during the last decade. Municipal solid waste statistics and management practices including waste recovery and recycling initiatives have been evaluated. Detailed data on solid waste management practices including collection, recovery and disposal, together with the results of cost analyses, have been presented. Based on these evaluations basic cost estimations on collection and sorting of recyclable solid waste in Turkey have been provided. The results indicate that the household solid waste generation in Turkey, per capita, is around 0.6 kg/year, whereas municipal solid waste generation is close to 1 kg/year. The major constituents of municipal solid waste are organic in nature and approximately 1/4 of municipal solid waste is recyclable. Separate collection programmes for recyclable household waste by more than 60 municipalities, continuing in excess of 3 years, demonstrate solid evidence for public acceptance and continuing support from the citizens. Opinion polls indicate that more than 80% of the population in the project regions is ready and willing to participate in separate collection programmes. The analysis of output data of the Material Recovery Facilities shows that, although paper, including cardboard, is the main constituent, the composition of recyclable waste varies strongly by the source or the type of collection point.     

Packaging waste recycling in Europe: Is the industry paying for it?

This paper describes and examines the schemes established in five EU countries for the recycling of packaging waste. The changes in packaging waste management were mainly implemented since the Directive 94/62/EC on packaging and packaging waste entered into force. The analysis of the five systems allowed the authors to identify very different approaches to cope with the same problem: meet the recovery and recycling targets imposed by EU law. Packaging waste is a responsibility of the industry. However, local governments are generally in charge of waste management, particularly in countries with Green Dot schemes or similar extended producer responsibility systems. This leads to the need of establishing a system of financial transfers between the industry and the local governments (particularly regarding the extra costs involved with selective collection and sorting). Using the same methodological approach, the authors also compare the costs and benefits of recycling from the perspective of local public authorities for France, Portugal and Romania. Since the purpose of the current paper is to take note of who is paying for the incremental costs of recycling and whether the industry (i.e. the consumer) is paying for the net financial costs of packaging waste management, environmental impacts are not included in the analysis. The work carried out in this paper highlights some aspects that are prone to be improved and raises several questions that will require further research. In the three countries analyzed more closely in this paper the industry is not paying the net financial cost of packaging waste management. In fact, if the savings attained by diverting packaging waste from other treatment (e.g. landfilling) and the public subsidies to the investment on the “recycling system” are not considered, it seems that the industry should increase the financial support to local authorities (by 125% in France, 50% in Portugal and 170% in Romania). However, in France and Portugal the industry is paying local authorities more than just the incremental costs of recycling (full costs of selective collection and sorting minus the avoided costs). To provide a more definitive judgment on the fairness of the systems it will be necessary to assess the cost efficiency of waste management operators (and judge whether operators are claiming costs or eliciting “prices”).     

Comparison of different collection systems for sorted household waste in Sweden

Composition and quantity per person of municipal solid waste (MSW) have been analyzed in six municipalities in southern Sweden with similar socio-economic conditions but with different collection systems. Samples of residual waste have been sorted, classified and weighed in 21 categories during 26 analyses that took place from 1998-2004. Collection data of the total waste flow, including source sorted recycling materials, in the same area have been compiled and compared. Multivariate data analyses have been applied. Weight-based billing reduced delivered amounts of residual household waste by 50%, but it is unknown to what extent improper material paths had developed. With curbside collection more metal, plastic and paper packaging was separated and left to recycling. When separate collection of biodegradables was included in the curbside system, the overall sorting of dry recyclables increased. The large uncertainty associated with waste composition analyses makes it difficult to draw strong conclusions regarding the effects on specific recyclables or the changes in the composition of the residual waste.     

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。     

LCA of integrated MSW management systems: case study of the Bologna District

LCA as a decision-supporting tool in planning integrated municipal solid waste management is not, as yet, widely used in Italy. This paper presents a study concerning the application of the LCA methodology to support the development of the new waste management plan for the Bologna District. The main goal of the study was to show decision-makers at the political level the benefits obtainable with the use of LCA, in terms of the identification and quantification of the potential environmental impacts of different waste management strategies. The integrated waste management system of the Bologna District includes waste collection and transport, sorting, recycling, composting, incineration and landfilling. Three scenarios, referring to 2006 and assuming the presence of 950,000 inhabitants and the production of approximately 566,000 t of waste in the district, have been compared. A detailed model has been developed in order to capture effects related to the waste fraction from separated collection and to the different waste treatments. The discussion of the results has focussed in particular on the greenhouse effect and the acidification potential. On the basis of the results obtained, the analysis of an additional scenario characterised by a further increase in separated collection has been put forward.     

Use of recycling stations in Borlänge, Sweden--volume weights and attitudes

This paper presents a study of recycling stations in the municipality of Borl?nge, Sweden. The main objectives were to measure volume weights of recyclables, to facilitate future planning of collection intervals and bin/container volume, and to investigate the general attitudes among the public towards waste management in general and recycling stations in particular. Volume weights measured in bins/containers were: paper/newsprint: 297 kg/m3, glass packaging: 297 kg/m3, metal packaging: 81.7 kg/m3, paper packaging: 27.8 kg/m3, plastic packaging: 28.1 kg/m3. The recycling stations have been in use since 1994. Most visitors (90%) arrived by car but said the visit to the recycling station was not the main purpose of the trip. The results from the interviews indicated that the people who use the recycling stations have found ways to incorporate waste sorting into their everyday lives, with the help of information, design of the collection system and environmental concerns.     

Energy efficiency of substance and energy recovery of selected waste fractions

In order to reduce the ecological impact of resource exploitation, the EU calls for sustainable options to increase the efficiency and productivity of the utilization of natural resources. This target can only be achieved by considering resource recovery from waste comprehensively. However, waste management measures have to be investigated critically and all aspects of substance-related recycling and energy recovery have to be carefully balanced. This article compares recovery methods for selected waste fractions with regard to their energy efficiency.Whether material recycling or energy recovery is the most energy efficient solution, is a question of particular relevance with regard to the following waste fractions: paper and cardboard, plastics and biowaste and also indirectly metals. For the described material categories material recycling has advantages compared to energy recovery. In accordance with the improved energy efficiency of substance opposed to energy recovery, substance-related recycling causes lower emissions of green house gases.For the fractions paper and cardboard, plastics, biowaste and metals it becomes apparent, that intensification of the separate collection systems in combination with a more intensive use of sorting technologies can increase the extent of material recycling. Collection and sorting systems must be coordinated. The objective of the overall system must be to achieve an optimum of the highest possible recovery rates in combination with a high quality of recyclables.The energy efficiency of substance related recycling of biowaste can be increased by intensifying the use of anaerobic technologies. In order to increase the energy efficiency of the overall system, the energy efficiencies of energy recovery plants must be increased so that the waste unsuitable for substance recycling is recycled or treated with the highest possible energy yield.     

Time series analysis of the effects of refuse collection on recycling: Taiwan's "Keep Trash Off the Ground" measure

The state of recycling in Taiwan has seen significant achievements due to various recycling policies implemented by environmental agencies in recent years. These policies include the "Keep Trash Off the Ground" (KTOG) measure, the "Four-in-One Recycling Plan", the per-bag trash collection fee and mandatory garbage sorting. An important question worthy of study is which of these policies has had a more pervasive and critical impact on the outcome of recycling. For example, there is evidence that the KTOG measure made it more convenient for people to begin recycling. This study therefore first analyzed the monthly data over the past decade on the amounts of recyclables in Taiwan's three major cities. By examining time series plots and employing an analysis of the time series intervention model, we can better understand the extent of the effects of the KTOG measure on these cities' amounts of recyclables. The same effects were also analyzed for the mandatory garbage sorting policy and the per-bag trash collection fee. Results show that the KTOG measure, essentially a change in refuse collection practice, presented consistent and significant effects on these cities' amounts of recyclables. It is suggested that the key to improving participation in a recycling program in waste management is for techniques to be tailored to actual settings in a way that facilitates citizen cooperation.     

Life cycle assessment of a packaging waste recycling system in Portugal

Life Cycle Assessment (LCA) has been used to assess the environmental impacts associated with an activity or product life cycle. It has also been applied to assess the environmental performance related to waste management activities. This study analyses the packaging waste management system of a local public authority in Portugal. The operations of selective and refuse collection, sorting, recycling, landfilling and incineration of packaging waste were considered. The packaging waste management system in operation in 2010, which we called “Baseline” scenario, was compared with two hypothetical scenarios where all the packaging waste that was selectively collected in 2010 would undergo the refuse collection system and would be sent directly to incineration (called “Incineration” scenario) or to landfill (“Landfill” scenario). Overall, the results show that the “Baseline” scenario is more environmentally sound than the hypothetical scenarios.     

The ecological relevance of transport in waste disposal systems in Western Europe

With the development of modern waste management systems in Western Europe, a remarkable increase in the distances for waste transportation has been observed. The question thus arises whether recycling with longer transport distances is ecologically advantageous or whether disposal without recycling is to be preferred. This situation was analysed using selected product and waste streams. This included refrigerators, paper, polyethylene films and expanded polystyrene. For each of these streams, a life cycle analysis was conducted with an emphasis on waste transport. The system boundaries were set in terms of the generation of waste to recycling or landfilling. The comparison included several scenarios with recycling and different transport distances. Landfilling was used as the reference scenario. The results obtained demonstrated how transport distances influence the ecological benefit of recycling. In the case of expanded polystyrene, the ecological boundaries are reached in practical situations, while with other materials these boundaries are far from being attained. In these cases, more complex and elaborate collection schemes, such as kerbside collection, which is economically convenient and shows the highest collection rates, can also be recommended.     

Solid Waste Recycling And Reuse In Bangkok

Materials recovered from solid waste in Bangkok are mainly glass bottles, paper and paper products, plastic products and metals. Materials are separated at three different stages of the collection process: at the source, prior to collection; by the crews of the collection vehicle; and by the scavengers at the dump site. The total daily tonnage of recyclable garbage collected at the source by the waste pickers is estimated at 286 tonnes, about 5% of the garbage collected by the city. There are small scale recycling shops (SSR) located around the main disposal sites where collected materials are sold by the collection crews and the scavengers. The quantity of materials delivered to the SSR shops by the collection crew vary between 1-6 tonnes per day. The amount of materials recovered by the scavengers (at the dump site) varies between 50-150 kg person^-1 day^-1. Therefore around 7.5% of the solid waste is recycled. In Bangkok both formal and informal sectors manufacture paper pulp, cardboard boxes and magazines from the recyclable paper. Paper products which account for 55% of the total waste stream are considered as the largest "product group" in the municipal solid waste. Recyclable glass (1-3% of the total waste stream) or cullet is used to manufacture plain glasses or cups. Plastics constitute about 10-15% of the waste stream. The benefit/cost ratios of production of most of these industries were reported to be higher than 1.5. In order to enhance recycling, legislative measures need to be introduced and enforced. In Thailand, there is, however, no law concerning recycling. There is no incentive for the consumer to separate solid waste for recycling, as the prices of waste in Bangkok are low and inconsistent. Therefore the pricing system should be more organized for recycling to be more effective.     

Municipal solid waste disposal in Portugal

In recent years municipal solid waste (MSW) disposal has been one of the most important environmental problems for all of the Portuguese regions. The basic principles of MSW management in Portugal are: (1) prevention or reduction, (2) reuse, (3) recovery (e.g., recycling, incineration with heat recovery), and (4) polluter-pay principle. A brief history of legislative trends in waste management is provided herein as background for current waste management and recycling activities. The paper also presents and discusses the municipal solid waste management in Portugal and is based primarily on a national inquiry carried out in 2003 and directed to the MSW management entities. Additionally, the MSW responsibility and management structure in Portugal is presented, together with the present situation of production, collection, recycling, treatment and elimination of MSW. Results showed that 96% of MSW was collected mixed (4% was separately collected) and that 68% was disposed of in landfill, 21% was incinerated at waste-to-energy plants, 8% was treated at organic waste recovery plants and 3% was delivered to sorting. The average generation rate of MSW was 1.32 kg/capita/day.     

Household food waste separation behavior and the importance of convenience

Two different strategies aiming at increasing household source-separation of food waste were assessed through a case-study in a Swedish residential area (a) use of written information, distributed as leaflets amongst households and (b) installation of equipment for source-segregation of waste with the aim of increasing convenience food waste sorting in kitchens. Weightings of separately collected food waste before and after distribution of written information suggest that this resulted in neither a significant increased amount of separately collected food waste, nor an increased source-separation ratio. After installation of sorting equipment in households, both the amount of separately collected food waste as well as the source-separation ratio increased vastly. Long-term monitoring shows that results where longstanding. Results emphasize the importance of convenience and existence of infrastructure necessary for source-segregation of waste as important factors for household waste recycling, but also highlight the need of addressing these aspects where waste is generated, i.e. already inside the household.     

Medical waste management in Trachea region of Turkey: suggested remedial action.

The main objective of this paper was to analyse the present status of medical waste management in the Trachea region of Turkey and subsequently to draw up a policy regarded with generation, collection, on-site handling, storage, processing, recycling, transportation and safe disposal of medical wastes. This paper also presents the results of study about awareness on how to handle expired drugs. Initially all health-care establishments in Tekirda?, Edirne and Kyrklareli provinces in Trachea region were identified and the amounts of hospital wastes generated by each of them were determined. Current medical waste-management practices, including storage, collection, transportation and disposal, in surveyed establishments were identified. Finally, according to results, remedial measurements for medical waste management in these establishments were suggested. Unfortunately, medical wastes are not given proper attention and these wastes are disposed of together with municipal and industrial solid wastes. The current disposal method is both a public health and environmental hazard. When landfill sites are visited, many scavengers can be seen sorting for recyclable materials, a practice which is dangerous for the scavengers. In addition, it was found that some staff in health-care establishments are unaware of the hazard of medical wastes. It is concluded that a new management system, which consists of segregation, material substitution, minimization, sanitary landfilling and alternative medical waste treatment methods should be carried out. For the best appropriate medical waste management system, health-care establishment employers, managers and especially the members of house- keeping divisions should be involved in medical waste management practice.     

Recycling in Davis,California

The waste collection and recycling programme at Davis, California, is described. The programme provides for separate collection of paper, glass, metal and garden waste, in addition to garbage collection; the public may deliver used motor oil and sell clean waste aluminium to the recycling center; garden waste and leaves are composted. Public relations activities are described. Although the recycling programme does not make money, but just covers the cost of operation, the environmental and social benefits are important.