Recent Resources, Conservation and Recycling Articles
Review of sustainability management initiatives within Finnish forest products industry companies—Translating Eu level steering into proactive initiatives
R. Husgafvel | G. Watkins | L. Linkosalmi | O. Dahl
Abstract: Sustainability has become a major focus area within forest products industry. The European operational environment and national environmental steering in EU member states highlight the importance of sustainable development and the development of associated new management approaches to promote sustainability. This article reviews some key elements of sustainability management, covering examples of both Finnish forest products industry initiatives and public environmental steering at the European level. An assessment is made of the current situation and an outline of a future outlook for sustainability management, with special emphasis on bridging the gap between industry initiatives and environmental steering in the form of legislation, policies and strategies at the EU level.This study applied a hybrid approach comprising a review of EU sustainability initiatives, a policy and legal review and a questionnaire survey of forest industry actors. The results of the future outlook indicate that energy efficiency is perceived to be the most important focus area in addition to e.g. environmental and waste management and recycling. Less than half of the companies aim at applying sustainability management. Life-cycle management is also considered to be important whereas product-based approaches, climate change and local industrial symbiosis receive very little attention. All responding companies aim to integrate the principles of sustainability into their operations and most companies consider that life-cycle thinking, management and assessment are useful for them. Energy efficiency is identified as the most important focus area with energy and materials efficiency seen as the most crucial factors for the achievement of responsible competitive advantage and building of sustainable value-added. The findings indicate that sustainability and life-cycle management are not receiving enough management focus at the moment and neither is the industry receiving enough guidance at either the EU level or via national steering and regulatory frameworks.
Jeng Shiun Lim | Zainuddin Abdul Manan | Haslenda Hashim | Sharifah Rafidah Wan Alwi
Abstract: Increased competitiveness and the growing demands for rice have stimulated the transformation of a conventional rice mill into an integrated, resource-efficient (IRE) rice mill complex. The IRE rice mill complex utilises the by-products from a rice milling process that include the broken rice, rice bran and rice husk, to produce value-added products and energy resources. This paper reviews the current processes and technologies employed in a conventional rice mill. It also highlights the current baseline practices of rice milling that offers vast opportunities for optimising the rice mill's utility system and for value-adding the by-products. Towards these ends, the concept of an IRE rice mill complex has been introduced as a potential solution, along with the mass and energy balances of the key resources. Finally, the paper highlights the key challenges in designing an IRE rice mill complex for both private millers and large rice enterprises.
Elemental analysis of lightweight metal scraps recovered by an automatic sorting technique combining a weight meter and a laser 3D shape-detection system
Shigeki Koyanaka | Kenichiro Kobayashi | Yoshitake Yamamoto | Masato Kimura | Kenso Rokucho
Abstract: To verify the effectiveness of a new automatic sorting technique that combines a weight meter and a laser 3D shape-detection system, elemental analysis of lightweight metal scraps generated in end-of-life vehicle (ELV) shredder facilities was conducted using a handheld XRF analyzer. According to their 3D shape and chemical composition, aluminum scraps were classified into cast alloy (Alc) and wrought alloy (Alw) fragments, and magnesium scraps were classified into irregularly shaped and rod-like fragments. The average chemical composition of a group of fragments was estimated before and after the separation test using the developed automatic sorting technique. The results show that the production of wrought aluminum alloy from the mixture of Alc and Alw fragments is not realistic because the contents of some alloying elements greatly exceed the standard values, although these alloying elements greatly decrease after the Alc fragments are separated out. For the magnesium scraps, after the rod-like magnesium fragments originating from the steering column were separated from the irregularly shaped fragments, the average chemical compositions of the rod-like products and the irregularly shaped products clearly approached the standard compositions of AM60B and AZ91D alloys, respectively. Thus, it was confirmed that the developed automatic sorting technique contributes to recycling of lightweight metal scrap in the automobile industry.
Best practice measures assessment for construction and demolition waste management in building constructions
Paola Villoria Saez | Mercedes del Río Merino | Alicia San-Antonio González | César Porras-Amores
Abstract: Currently the construction and demolition (C&D) waste collection system in Spain is managed in a decentralized manner by each sub-contracted company. This lack of comprehensive strategy for C&D waste management causes a confusing and sometimes individual attitude regarding the different measures for C&D waste. Therefore effective waste management should be enforced. Construction stakeholders have wide range of best practices in C&D waste management that can be implemented, so they need to be assessed for their effectiveness.The aim of this research study is to assist construction stakeholders in making a decision on C&D waste management. This paper carries out a survey conducted among the construction agents in order to evaluate the effectiveness of 20 best practice measures regarding C&D waste management, identifying the most suitable types of building constructions to implement these practices and also the advantages and drawbacks of their performance in a building construction project.Results of this study show that among the highly effective best practices are: the use of industrialized systems and the contract of suppliers managing the waste. In addition, distributing small containers in the work areas is also another high valued practice, although only 36% of respondents usually implement this measure in their works.
Lingyu Yan | Anjian Wang | Qishen Chen | Jianwu Li
Abstract: Zinc is one of the most widely applied nonferrous metals in China. Study on the applications and recurrent situation of zinc resources is of great strategic importance for the sustainable development of China's economy. In this paper, a dynamic material flow analysis (MFA) method has been adopted to analyze quantificationally zinc resources in China, as well as to analyze and predict the quantity of zinc product scrap and their recycling situation. The weighted average method was applied to calculate average lifetimes of six major zinc products in China. The average lifetimes of battery, zinc oxide, zinc die-casting alloys, zinc material products, galvanized zinc and brass are 0.17, 5.3, 11.1, 12, 21 and 30 years, respectively. Assuming the lifetime of zinc product group obeys the Weibull distribution and the consumption of zinc products varies linearly with time, the future consumption and scrap generation of zinc products will increase continuously. It is expected that they would increase from 49% to 76% during 2004–2020, respectively. Assuming the recycling rate remains unchanged with time, the zinc old scrap index, both the theoretical and actual values, would continue increasing in China. The values are expected to reach 0.402 and 0.076 by 2020, respectively. Therefore, the regeneration resource of depreciated zinc is actually insufficient in China. According to the scenario analysis, the actual value of old scrap indexes is positively correlated with the recycling rate of zinc products. Because galvanized products are the largest consumption area of zinc products in China, the influence of their recycling rate on old scrap index is obviously larger than other zinc products. Through the analysis, this paper suggests that the increase of the recycling rate of zinc products could not only improve to a certain degree China's relative shortage of zinc resources, but greatly relive the supply pressure of zinc in the world.
Gordon W.S. Lane | Travis P. Wagner
Abstract: This paper explores the impact of recycling container attributes on household recycling practices in municipal recycling programs. While there is little in the academic literature on the specific relevance of container design on recycling programs, unpublished data and gray literature suggest factors such as container size, type, and color can impact recycling rates. Because municipal recycling program design decisions likely are based on unpublished data and gray literature—much in the form of municipal-level reports written by consultants—we review these sources and place them in the context of academic literature. Additionally, we present new data on current program designs from a nationwide survey of US municipal and county solid waste professionals. Anecdotes from the survey confirm findings of previously published studies that have correlated larger recycling containers and the use of wheeled recycling containers with greater recycling rates. However, data on the direct effect of each of these factors and container color remains elusive due to a lack of controlled studies.
Dongguo Shao | Xuezhi Tan | Huanhuan Liu | Haidong Yang | Chun Xiao | Fengshun Yang
Abstract: Water reuse and pollutant removal efficiency analysis of the on-farm irrigation tanks (OFTs) was carried out in rice paddy field region of Zhanghe Irrigation District, Southern China through field experiments during the rice growing season of 2009–2011. Water flow measurements indicate that 20.6–68.9% of drainage water captured by OFTs was reused for supplemental irrigation. Rainfall was the most important factor that determines the water reuse efficiency (WRR) of OFTs, since higher rainfall resulted in higher surplus irrigation water draining out of OFTs without reuse, and thus decreased WRR. Fully using the storage capacity for storing return flow, and releasing totally for supplemental irrigation also enhanced WRR of OFTs. Water quality analysis shows that OFTs removed 47.2% of total phosphorous (TP) and 60.8% of total nitrogen (TN) of inflow and have a great effect on increasing sedimentation for return flow as the mean of removal efficiency of pollutant load (REL) for suspended solids (SS) amounted to 68.4%. For water treatment effectiveness of OFTs, high hydraulic retention time (HRT) is most beneficial to increase REL of TN whereas REL of TP is not sensitive to HRT. These results confirm that OFTs can effectively increase agricultural return flow reuse and remove pollutants. As the cascade OFTs irrigation system recycle return flow for several times, the irrigation water demand from outside of region was reduced significantly for rice production. Coupling with the effect of cyclic irrigation on the nutrients recycling by paddy fields, OFTs irrigation system also considerably mitigate the N and P off-site emission. Therefore, it is advisable to integrate the role of OFTs on water reuse and treatment for water saving irrigation and ecological management of paddy fields landscape.
Y.R. Loh | D. Sujan | M.E. Rahman | C.A. Das
Abstract: The natural, bio-degradable features and chemical constituents of the sugarcane bagasse (SCB) have been attracting attention as a highly potential and versatile ingredient in composite materials. Eco-friendly and low cost considerations have set the momentum for material science researchers to identify green materials that give low pollutant indexes. Various components of SCB is shown to possess the ability of being applied as raw material for manufacturing of composite materials at multiple levels of properties and performances. Studies on the impacts, performances and applications of SCB in its original condition; transformed forms; treated with appropriate chemicals and/or processes; in combination with materials of distinct properties and manipulation of manufacturing methodologies have been duly considered. This paper attempts to summarize a review of current literature on the extensive studies that have been undertaken in an attempt to explore plausible applications and potentials of SCB for composite material.
Role of behavioural factors in green supply chain management implementation in Indian mining industries
Available online 18 May 2013
Kamalakanta Muduli | Kannan Govindan | Akhilesh Barve | Devika Kannan | Yong Geng
Abstract: Green supply chain management (GSCM) integrates ecological concepts with those of supply chain management in order to minimize energy and material usage and to reduce adverse impacts of supply chain activities on the environment. GSCM implementation in mining industries depends largely upon certain factors which are influenced by human behaviours. Human behaviour is dynamic in nature and the relationships between them continuously evolve and change. In this ever-changing context, therefore, identifying and ranking the behavioural factors that affect GSCM implementation becomes essential. This can be taken as a reference by the decision makers while deciding the hierarchy of action necessary for effective implementation of green practices in mining supply chains. The present research attempts to explore various behavioural factors affecting GCSM practices and their interactions which help to attain green-enabled needs. Interpretive structural modelling (ISM) is employed in this research to extract the interrelationships among the identified behavioural factors.
Environmental training in organisations: From a literature review to a framework for future research
Charbel José Chiappetta Jabbour
Abstract: Although the research on the relationship between human factors and environmental sustainability is slowly progressing, environmental training has attracted the most attention from researchers and practitioners. However, there remains a lack of research that integrates and systematises the available knowledge on organisational environmental training. Environmental training is fundamental to any successful activity of environmental management, conservation and recycling of resources. Thus, the aim of this paper was to present the results of a systematic literature review on environmental training in organisations. The main studies in this area were classified and coded, and a research agenda with 9 recommendations that may advance the field was presented. As a result of the gaps in the current literature, a framework was proposed aiming guide and strengthens the state-of-the-art research on environmental training. Additionally, results show that more research is needed on environmental training, combining training and green human resource management and defining/measuring the objectives of the environmental training actions. Future studies should also consider mixed methodologies and comparative perspectives.
Ali Diabat | Devika Kannan | Mathiyazhagan Kaliyan | Davor Svetinovic
Abstract: Current environmental issues emerging in the world are reflected in the environmental legislation of several countries. Because environmental issues are important, industries actively seek ways in which to reduce their environmental footprint. One effective method is through the use of reverse logistics. Reverse logistics is the concept of reusing used products in order to reduce wastes and to increase an industry's environmental performance and resulting profits. Stock selection, transportation, centralized collection, data collection, refurbishing, and remanufacturing are some of the more commonly utilized reverse logistic operations. An effective reverse logistics network is essential for increasing the flow of goods from customers to producers. The objective of this paper is to develop a multi-echelon reverse logistics network for product returns to minimize the total reverse logistics cost, which consists of renting, inventory carrying, material handling, setup, and shipping costs. Industries need to give more attention to the task of collecting used products from customers and establishing collection facilities. In this study, a mixed integer non-linear programming (MINLP) model is developed to find out the number and location of initial collection points and centralized return centers required for an effective return and collection system, and also the maximum holding time (collection frequency) for aggregation of small volumes of returned products into large shipments. Two solution approaches, namely genetic algorithm and artificial immune system, are implemented and compared. The usefulness of the proposed model and algorithm are demonstrated via an illustrative example.
A fuzzy multi criteria approach for evaluating green supplier's performance in green supply chain with linguistic preferences
Lixin Shen | Laya Olfat | Kannan Govindan | Roohollah Khodaverdi | Ali Diabat
Abstract: Today's international business environment has forced many firms to focus on supply chain management to gain a competitive advantage. During recent years, supplier selection process in the supply chain has become a key strategic consideration. With the growing worldwide awareness of environmental protection and the corresponding increase in legislation and regulations, green purchasing has become an important issue for companies to gain environmental sustainability. Traditionally, companies consider criteria such as price, quality and lead time, when evaluating supplier performance and do not give enough attention to environmental criteria as a means to evaluate suppliers. Now, many companies have begun to implement green supply chain management (GSCM) and to consider environmental issues and the measurement of their suppliers’ environmental performance. This paper examines GSCM to propose a fuzzy multi criteria approach for green suppliers’ evaluation. We apply fuzzy set theory to translate the subjective human perceptions into a solid crisp value. These linguistic preferences are combined through fuzzy TOPSIS to generate an overall performance score for each supplier. A numerical example is presented to demonstrate the effectiveness of the proposed approach.
A comparison of two models for dealing with urban solid waste: Management by contract and management by public–private partnership
Adauto Fernandes Marconsin | Derval dos Santos Rosa
Abstract: In work, we compared two models for dealing with urban solid waste in Brazil, namely, management by contract and management by public–private partnership. Management by contract, which is widely used by the public sector (municipalities) for urban solid waste collection and disposal and for acquiring goods and services for periods not greater than 60 months, is governed by Federal Law 8.666/93. Management by public–private partnership is governed by Federal Law 11.079/04 for contracts worth more than US$11,000,000 and involves costs for the private partner and public partner. The financial return for the private partner must be clearly delineated and the contract should last from 5 to 35 years. Management by public–private partnership that involves the management of municipal solid waste is very recent in Brazil. For this reason, the comparison between the two forms of management of municipal solid waste (management by contract and management by public–private partnership) described in this work is unprecedented in this country. Both of these models are used in the municipality of São Bernardo do Campo in the State of São Paulo, Brazil. For this study, information was gathered through semi-structured interviews with public works managers in São Bernardo do Campo, with members of an Association of Recyclable Material Collectors and with managers of a company contracted by the São Bernardo do Campo city hall, and also by researching public documents provided by the city hall. The interviews with the managers of the municipality of São Bernardo do Campo, the Association and the company were held in the headquarters of each institution. The documents analyzed, such as the plan for dealing with municipal solid waste, contracts and bids were made available electronically. Analysis of the results indicated that management by a public–private partnership was more advantageous for dealing with urban solid waste than management by contract since the former provided a strong selective collection program, reduced the amount of solid waste sent to sanitary embankments, led to the recovery an area of land previously degraded by the incorrect disposal of urban solid waste and stimulated the installation of an energy recovery unit.
Adrien Capony | Bogdan Muresan | Michel Dauvergne | Jean-Claude Auriol | Valéry Ferber | Agnès Jullien
Abstract: This study presents the contributions of materials, earth engineering machines and construction techniques to potential environmental impacts from the main items of typical road earthworks. To achieve this goal, the overall activity at a 1.9-km long French earthworks project site for a heavily trafficked highway was surveyed during its 2007–2009 construction period. Using data collected and a numerical model of road life cycle assessment (LCA), i.e. ECORCE, six indicators could be evaluated, namely: energy consumption, global warming potential, acidification, eutrophication, photochemical ozone creation, and human chronic toxicity. When available, several life cycle inventories were implemented in order to appraise indicator sensitivity with respect to the considered panel of pollutants. Results also allowed estimating from an LCA point of view: (i) the conservation of both aggregates and soil as induced by quicklime treatment and (ii) the duration necessary for projected traffic levels to offset the potential environmental impacts of the earthworks stage.
Effectiveness of novel and traditional methods to incorporate industrial wastes in cementitious materials—An overview
Tongsheng Zhang | Peng Gao | Pinhai Gao | Jiangxiong Wei | Qijun Yu
Abstract: Sustainable development and eco-efficiency are urgent and imperative demands for the well-being of our planet, continued growth of a society, and human development. Traditional Portland cement production seems unsustainable due to consumption of huge natural resources and energy and significant CO2 emissions. The volume of industrial wastes is increasing significantly, leading to a number of economical and ecological problems. Although industrial wastes can be incorporated in cementitious materials by various traditional methods, the substitution ratio of industrial wastes in cementitious materials is relatively low to avoid unacceptable performance loss. Novel methods, such as improving hydraulic activities of metallurgical slags by adding composition adjusting material at high temperature, improving surface cementitious properties of fly ashes by dehydration and rehydration treatment, and arranging cement clinker and industrial wastes in the particle size distribution of blended cements according to their hydraulic activities, are reviewed. These methods provide more effective approach to prepare high performance blended cements with larger amount of industrial wastes, leading to a very significant role in CO2 emissions reducing, resources and energy conservation of the cement industry.
Pedro E. Sánchez-Jiménez | Luis A. Pérez-Maqueda | Antonio Perejón | José M. Criado
Abstract: In this paper, some clarifications regarding the use of model-fitting methods of kinetic analysis are provided in response to the lack of plot linearity and dispersion in the activation energy values for the thermal degradation of polystyrene found in the literature and some results proposing an nth order model as the most suitable one. In the present work, two model-fitting methods based on the differential and integral forms of the general kinetic equation are evaluated using both simulated and experimental data, showing that the differential method is recommended due to its higher discrimination power. Moreover, the intrinsic limitations of model-fitting methods are highlighted: the use of a limited set of kinetic models to fit experimental data and the ideal nature of such models. Finally, it is concluded that a chain scission model is more appropriate than first order.
James Cooper | Cynthia Carliell-Marquet
Abstract: Phosphorus (P) is both an essential resource, required for plant growth and food production, and a costly pollutant, capable of causing eutrophication in water courses. The possibility of future phosphorus scarcity and the requirement to improve the quality of UK waters necessitates the development of a UK phosphorus management system, which increases use efficiency, reduces losses and recycles wastes more effectively. A vital first step towards creating such a system is to conduct a substance flow analysis (SFA), which maps and quantifies the relevant stocks and flows, allowing specific measures to be implemented that target identified losses and areas of inefficient resource use. This paper presents the results of a SFA for phosphorus in the UK, focussing in particular on the food production and consumption system for the year 2009. The SFA results suggest that the UK population consumed around 31.0kt P in 2009, which was largely achieved by importing food, feed and fertilisers, with net imports totalling 113.5kt P. Imported fertilisers accounted for 56% of the total imports, containing 77.5kt P. The largest losses within the systems were those to water, estimated at around 41.5kt P/yr, and soil accumulations are estimated at 37.5kt P/yr. The efficiency of UK crop production is estimated at 81%, whereas the efficiency of producing animal products is only 16.5%. Wastewater treatment works (WwTW) received around 55.0kt P within wastewater, with 57% being removed in sewage sludge. The 23.5kt P discharged within final effluent represented the largest loss to UK waters. Around 71% of the sludge was recycled to land, containing 22.5kt P, although the rate of application was around 5× higher than the uptake rate for crops, demonstrating the challenges of effectively recycling bulky wastes. Existing measures aimed at tackling water pollution and climate change have acted to improve P management in the UK, although additional measures focussing particularly on P as a resource are required. The results from this analysis suggest focussing on P removal and recovery at WwTW, as well as developing more effective methods for recycling bulky wastes such as animal manure, food waste and sewage sludge in order to reduce soil accumulations and replace imported fertilisers. Conducting additional SFAs at smaller scales may be necessary in order to develop more specific measures, such as regional recycling strategies.
Life cycle assessment of hot mix asphalt and zeolite-based warm mix asphalt with reclaimed asphalt pavement
Rosario Vidal | Enrique Moliner | Germán Martínez | M. Carmen Rubio
Abstract: A comprehensive life cycle assessment of asphalt pavements was conducted including hot mix asphalt (HMA), warm mix asphalt (WMA) with the addition of synthetic zeolites, and asphalt mixes with reclaimed asphalt pavement (RAP). The environmental impacts associated with energy consumption and air emissions were assessed, as well as other environmental impacts resulting from the extraction and processing of minerals, binders and chemical additives; asphalt production; transportation of materials; asphalt paving; road traffic on the pavement; land use; dismantling of the pavement at the end-of-life and its landfill disposal or recycling. Monte Carlo simulations were also conducted to take into account the variability of critical input parameters. Taking into account the entire life cycle, the impacts of zeolite-based WMA pavements were almost equal to the impacts of HMA pavements with the same RAP content. The reduction in the impacts of WMA resulting from the lowering of the manufacturing temperature was offset by the greater impacts of the materials used, especially the impacts of the synthetic zeolites. Moreover, by comparing asphalt mixes with different RAP contents, it was shown that the impacts of asphalt mixes were significantly reduced when RAP was added. All endpoint impacts as well as climate change, fossil depletion and total cumulative energy demand were decreased by 13–14% by adding 15% RAP. A key advantage of WMA is the potentially greater use of RAP. Thus, the decrease in the impacts achieved by adding large amounts of RAP to WMA could turn these asphalt mixes into a good alternative to HMA in environmental terms.
A cost and benefit analysis of future end-of-life vehicle glazing recycling in France: A systematic approach
Romain Farel | Bernard Yannou | Asma Ghaffari | Yann Leroy
Abstract: As with other European countries, the French automotive industry needs to improve the end-of-life vehicle (ELV) recycling rate in order to reach the minimum reuse and recovery rate required by EU directives. This paper proposes a model to investigate the potential cost and benefit of ELV glazing recycling for all value-chain stakeholders, and for the network as a whole. Key parameters of future changes, namely glass cullet price, landfill cost, network coverage and transportation costs are identified at the level of field research. A system dynamics approach is then used to simulate the net economic balance of the recycling network under different future scenarios. The simulation reveals an increase in the income and considerable cost savings as a result of the recycling network in some of future scenarios.
Yongwon Seo | Jungkyu Ahn | Young-Oh Kim
Abstract: The assessment of the impact of climate change depends not only on quantitative changes in precipitation but also system characteristics that can be changed and enhanced. This study investigated the effect of building the shared network of a rainwater harvesting system as an adaptation to climate change scenarios. The performance of a rain barrel network under three climate change scenarios and three global circulation models (GCM) is examined. A sample community composed of four prospective users with individual storage is tested with various forms of shared connections. Most importantly, the results show that the benefit from shared rain barrels greatly increases under the climate change conditions compared with the historical rainfall data. Especially, for high reliabilities, the results indicate that the benefit of a rain barrel network increases under future climate change scenarios, whereas it does not show apparent improvement for low reliabilities. However, the performance of a rain barrel network is highly dependent on location and climate change scenarios. In contrast, the GCM does not considerably affect the performance of the shared network. The results of this study highlight the needs to establish sharing networks of rainwater harvesting systems under the climate change conditions, which would significantly increase the benefit of the entire community.
Liangxin Fan | Guobin Liu | Fei Wang | Violette Geissen | Coen J. Ritsema | Yan Tong
Abstract: Fully understanding patterns of water use and water conservation among different consumer groups will help in implementing more effective water conservation programs worldwide. Consequently, we investigated water use patterns, water conservation practices, attitudes, and hindrances to water conservation by randomly surveying 776 households in the Weinan, Yanglin–Wugong, and Baoji districts in the middle of the Wei River Basin. The results of the study reveal that water consumption for domestic use of 70.2L per capita per day (Lpcd), 31.9L of which is allocated for outdoor use. Households with high water consumption consume more water for watering vegetable gardens and cleaning their houses and yards, and employ more appliances and apparatuses that use water. A total of 20 conservation practices were reported by of which 11 were used by the majority of residents. Residents prefer to implement the most convenient and low-cost water conservation practices. The households with low water consumption were likely to conserve water because of economic concerns, but their unwillingness to change traditional habits prevent them from conserving water. For households with high water consumption groups, environmental concerns drive them to conserve water, their unwillingness to devote additional time and energy and the lack of social support are the main hindrances to water conservation. Public education programs on water use and conservation for rural communities need to fully consider these limitations to change traditional views and behaviors toward the use of water appliances and improving quality of life, as well as employing outdoor water conservation, pro-environmental education, and price transparency to promote the judicious use of water. The results obtained can be used as guidelines for establishing policies for community water conservation.
Jingru Li | Zhikun Ding | Xuming Mi | Jiayuan Wang
Abstract: The increasing construction and demolition (C&D) waste causes both cost inefficiency and environmental pollution. Many countries have developed regulations to minimize C&D waste. Implementation of these regulations requires an understanding of the magnitude and material composition of waste stream. Construction waste generation index is a useful tool for estimating the amount of construction waste and can be used as a benchmark to enhance the sustainable performance of construction industry. This paper presents a model for quantifying waste generation per gross floor area (WGA) based on mass balance principle for building construction in China. WGAs for major types of material are estimated using purchased amount of major materials and their material waste rate (MWR). The WGA for minor quantities of materials is estimated together as a percentage of total construction waste. The model is applied to a newly constructed residential building in Shenzhen city of South China. The WGA of this project is 40.7kg/m2, and concrete waste is the largest contributor to the index. Comparisons with transportation records in site, empirical index in China and data in other economies reveal that the proposed model is valid and practical. The proposed model can be used to setup a benchmark WGA for Chinese construction industry by carrying out large-scale investigations in the future.
Chung-Chiang Chen | Yi-Tui Chen
Abstract: Whether to recycle the recyclable fraction in the MSW (municipal solid waste) or to incinerate it for energy recovery is a debating issue. In this paper we present a simple criterion to judge what type of waste components should be recycled or incinerated with energy recovery. According to the R1 formula presented by the waste framework directive (Directive 2008/98/EC of the European Parliament), this paper calculates the energy performances of MSW waste-to-energy plants currently operated in Taiwan firstly. By using the assumed value of energy recovery efficiency and carbon emission costs, we compare the treatment methods between recycling (material recovery) and energy recovery by the cost and benefit analysis, and examine the suitability of recycling for waste fractions of paper, food waste, PET, PVC, and plastic bags/films under a variety of scenarios. The results show that food waste is more appropriate to be treated by recycling while plastic bags/films are suggested to be incinerated with energy recovery.
Aaron Greenfield | T.E. Graedel
Abstract: Two centuries ago the diet of technology (the diversity of materials utilized) consisted largely of natural materials and a few metals. A century later, the diversity in the diet had expanded to perhaps a dozen materials in common use. In contrast, today's technology employs nearly every material in the periodic table, a behavior illustrated in this paper by the material evolution of electronics, medical technology, and the jet engine. Geological deposits in a given country or region tend to have only minimal to moderate elemental diversity, however. As a result, an extensive and diverse metal trade is required if modern technology is to be sustained. Some recent industry responses to elemental scarcity and implications for corporate and governmental policy are discussed.
Transitions of municipal solid waste management. Part I: Scenarios of Swiss waste glass-packaging disposal
Grégoire Meylan | Roman Seidl | Andy Spoerri
Abstract: All municipal solid waste (MSW) management systems—even “high quality systems” or those employing “best practices”—face multiple challenges, e.g., decreasing prices of secondary raw materials recovered by municipalities, increasing complexity of waste composition, technological lock-ins. Policy-making involves translating these challenges into goals that are generic in nature and implementing them on MSW fractions thanks to tailor-made policy tools, e.g., anticipated disposal fees. Anticipating the impacts of policies can provide valuable insights into the adequacy of policy tools with respect to economic, political, and social contexts of MSW. The goal of this paper is to construct consistent, future scenarios of Swiss waste glass-packaging disposal based on literature and stakeholder knowledge, including the allocation of waste to different disposal routes. These scenarios are future states to which the current system could transit to due to alternative policies in line with waste policy goals and varying societal constraints (e.g., commodity prices). Results of scenario construction show that policy has a limited effect on waste glass-packaging disposal because of economic constraints, preventing goals from consistently being achieved. For instance, increases in energy prices can impede a policy favoring recycling over downcycling to foam glass, an energy-saving product. The procedure applied to construct possible scenarios suits well the ambition of considering uncertain future developments affecting MSW management as it integrates qualitative and quantitative knowledge of various sources and disciplines.
Isabella de Castro Carvalho | Maria Lúcia Calijuri | Paula Peixoto Assemany | Marcos Dornelas Freitas Machado e Silva | Ronan Fernandes Moreira Neto | Aníbal da Fonseca Santiago | Mauro Henrique Batalha de Souza
Abstract: Airports consume significant amounts of water to maintain their infrastructure. Given the increasing worldwide demand for this type of transport and the current situation of water scarcity in many regions of the planet, efforts should be made to assess water consumption profiles as well as alternatives for its efficient use. In airport complexes, most of the water is used to meet non-potable demands, making them potential environments for implementing conservation practices aimed at reducing these demands – such as water metering and installation of water saving fixtures – and also for searching for alternative sources, such as rainwater and treated greywater or domestic sewage effluent. This review presents information regarding water consumption in globally important airports in order to provide a basis for studies that guide policies and decision-making toward a sustainable management of these environments during the planning and execution of construction, expansion and modernization projects.
Ink and dirt behavior in pulping after artificial aging of cold-set offset printed newspapers in different humidity conditions
Available online 21 April 2013
Kalle Kemppainen | Antti Haapala | Mika Körkkö | Jouko Niinimäki
Abstract: Although moisture has a decisive role in the permanence of cellulose and unprinted paper, its role in ink release from the surface of printed recovered papers remains unclear. This work aimed to determine whether various relative humidity levels in the artificial aging test affect ink release from the surface of the paper and its fibers when pulping cold-set offset printed newspapers in alkaline pulping conditions. The results showed that relative humidity variations from 30% to 70% negligibly affected ink release at 60°C. However, compared with these lower humidity levels, exposure to 90% relative humidity for at least 25h resulted in a higher ink content bound to fibers, a greater formation of visible dirt specks after pulping and a smaller formation of microscopic ink particles. In practical applications, the accurate estimation of climate effects during the storage and the transportation of recycled papers requires that humidity conditions are taken into account while performing artificial aging tests with paper products.
The paradox of packaging optimization – a characterization of packaging source reduction in the Netherlands
Mariësse A.E. van Sluisveld | Ernst Worrell
Abstract: The European Council Directive 94/62/EC for Packaging and Packaging Waste requires that Member States implement packaging waste prevention measures. However, consumption and subsequently packaging waste figures are still growing annually. It suggests that policies to accomplish packaging waste prevention do not suffice, especially since developments are less insightful as these are part of a self-declaring compliance system. This study is aimed at expanding the understanding of packaging source reduction. We collected and evaluated 131 available options implemented in the Netherlands in the period 2005–2010. Lightweighting has been identified as the most frequently applied packaging source reduction method, indicating that the packaging industry prioritizes low-effort and familiar concepts, despite the dichotomy in efficacy.
Ahmad Halilu Abba | Zainura Zainon Noor | Rafiu O. Yusuf | Mohd Fadhil M.D. Din | Mohd Ariffin Abu Hassan
Abstract: The views of the public on solid waste bound to be generated in Johor Bahru Malaysia are presented and appraised. This is because of the massive development currently going on to transform the city to an international standing by the year 2025. For this reason, attempts to raise stakeholder awareness on the need to embrace on how best to manage the current problem with reduced impacts to the environment currently and in the future was attempted. Data were collected through contacts and questionnaire survey. Analytical hierarchy process (AHP) technique was used to structure and assess the views and judgments of stakeholders on the environmental impacts of solid waste disposal. SuperDecision software was used to generate and compute results of stakeholder's judgments. The assessment revealed that fauna and flora, habitat depletion and land use among the criteria are most critical environmental impacts. Landfilling, recycling, incineration and composting were evaluated in terms of the environmental impacts. The choice of incineration is perceived to improve environmental visibility, preserves fauna and flora as well as stream ecology, improves environmental air quality and optimizes land use. Similarly, recycling of waste, is perceived to preserves fauna and flora, stream ecology, habitat depletion, improves air quality as well as land use. Composting is perceived to be the best option in terms of preservation of stream ecology, habitat depletion and land use practice. Landfill generates less noise and vibration but found to be responsible for more than 50% of the environmental impacts created by solid waste in this area. Composting and recycling are mostly preferred to landfilling and incineration and the reason why this is so was provided. The study also identified challenges ahead and highlights that benefits attached to some vital disposal options (such as incineration) are yet to be fully implemented.
Risk explicit interval linear programming model for long-term planning of vehicle recycling in the EU legislative context under uncertainty
Vladimir Simic | Branka Dimitrijevic
Abstract: With the number of vehicles expected to increase to 1.85 billion by 2030 and the scrap generated from end-of-life vehicles (ELVs) expected to be 3.71 billion tonnes, there is a strong motivation to properly process the flow of these materials. The EU Directive on end-of-life vehicles (EU ELV Directive) aims to increase recovery and recycling rates of ELVs in order to reduce waste and improve environmental performances. Long-term optimization planning of vehicle recycling is increasingly important. However, there is a lack of research of uncertainties in the vehicle recycling system, none of the previous studies analyzed the linkage and trade-offs between decision risk and system performances, and no previous research was reported on interval-based programming for vehicle recycling planning problem. In order to meet the imposed eco-efficiency quotas, maximize system profit and minimize decision risk, and at the same time fill the identified research gaps, a risk explicit interval linear programming model for optimal long-term planning in the EU vehicle recycling factories was developed. It can create optimal plans for procuring vehicle hulks, sorting of generated material fractions, allocation of sorted waste flows and allocation of sorted metals for desired value of the system aspiration level. A numerical study demonstrated the potentials and applicability of the proposed model. Vehicle recycling factories aim at reaching the highest possible level of quantity and quality of sorted metal flows. The future eco-efficiency quotas will not endanger their business. The success of the final phase of implementation of the EU ELV Directive is not jeopardized, because even the future eco-efficiency quotas were reached in all created test problems. Quantity of land-filled wastes will be radically reduced after January 1, 2015. The model results and trade-offs would be valuable for supporting the EU vehicle recycling factories in creating optimal long-term production strategies and reducing the risk for uncertain situations.
Critical aspects in the life cycle assessment (LCA) of bio-based materials – Reviewing methodologies and deriving recommendations
P. Pawelzik | M. Carus | J. Hotchkiss | R. Narayan | S. Selke | M. Wellisch | M. Weiss | B. Wicke | M.K. Patel
Abstract: Concerns over non-renewable fossil fuel supply and climate change have been driving the Renaissance of bio-based materials. To substantiate environmental claims, the impacts of bio-based materials are typically quantified by applying life cycle assessment (LCA). The internationally agreed LCA standards provide generic recommendations on how to evaluate the environmental impacts of products and services but do not address details that are specifically relevant for the life cycles of bio-based materials. Here, we provide an overview of key issues and methodologies explicitly pertinent to the LCA of bio-based materials. We argue that the treatment of biogenic carbon storage is critical for quantifying the greenhouse gas emissions of bio-based materials in comparison with petrochemical materials. We acknowledge that biogenic carbon storage remains controversial but recommend accounting for it, depending on product-specific life cycles and the likely time duration of carbon storage. If carbon storage is considered, co-product allocation is nontrivial and should be chosen with care in order to: (i) ensure that carbon storage is assigned to the main product and the co-product(s) in the intended manner and (ii) avoid double counting of stored carbon in the main product and once more in the co-product(s). Land-use change, soil degradation, water use, and impacts on soil carbon stocks and biodiversity are important aspects that have recently received attention. We explain various approaches to account for these and conclude that substantial methodological progress is necessary, which is however hampered by the complex and often case- and site-specific nature of impacts. With the exception of soil degradation, we recommend preliminary approaches for including these impacts in the LCA of bio-based materials. The use of attributional versus consequential LCA approaches is particularly relevant in the context of bio-based materials. We conclude that it is more challenging to prepare accurate consequential LCA studies, especially because these should account for future developments and secondary impacts around bio-based materials which are often difficult to anticipate and quantify. Although hampered by complexity and limited data availability, the application of the proposed approaches to the extent possible would allow obtaining a more comprehensive insight into the environmental impacts of the production, use, and disposal of bio-based materials.
Revealing an invisible giant: A comprehensive survey into return practices within original (closed-loop) supply chains
Harold Krikke | Dianne Hofenk | Yacan Wang
Abstract: Forward supply chain actors are increasingly involved in the full life cycle of their products and the packaging used. Where in the past these were disposed of via (public) waste management systems or sold in cascade markets, now returns management becomes key to focal companies. Moreover, recent literature emphasizes that returns can be a value creator rather than a cost of business as it can save the environment, provide critical resources and customer value. But relevant, up-to-date data on returns and return practices is scarce, whereas such data is essential to show the potential value of returns and make a business case for returns management to practitioners. Based on a global survey among manufacturers/wholesalers/retailers and third party service providers, this paper presents comprehensive descriptive statistics on and analysis of current return practices. We develop and test propositions on the drivers, volumes and value of different returns along the life cycle; show the inefficiencies in current return practices leading to value destruction instead of the advocated value creation; and compare return practices in different regions and industries. We also provide recommendations for converting value destruction into value creation. Although progress is slow, there are hopeful signals that the potential of returns managements will be unlocked in the near future.
V. Coman | B. Robotin | P. Ilea
Abstract: Nickel is an important metal, heavily utilized in industry mainly due to its anticorrosion properties. As a consequence, nickel containing wastes such as spent batteries and catalysts, wastewater and bleed-off electrolytes are generated in various processes. These wastes could have a negative impact on the environment and human health if they contaminate soil, water and air. The present review addresses the environmental and economical aspects of nickel recovery/removal from various types of wastes. The main physico-chemical technologies for processing various effluents and wastewaters containing nickel are reviewed and discussed. Nickel recovery from spent batteries, catalysts, electronic waste and other sources is described. Hydrometallurgical approaches are emphasized. Recovery of nickel from wastes is important not only for economical aspects, but also for environmental protection.
Urban solid waste plant treatment in Brazil: Is there a net emergy yield on the recovered materials?
Feni Agostinho | Cecília M.V.B. Almeida | Silvia H. Bonilla | José B. Sacomano | Biagio F. Giannetti
Abstract: Disposal alternatives of urban solid waste (USW) are being considered one of the main topics on the political agenda worldwide due to high concerns related to economic, social and environmental issues. In São Paulo Municipality, Brazil, the Sorting and Composting Waste Treatment Plant (SCWTP) is suggested as an appropriated way to manage the 14,000Mg of USW generated daily by 11 million inhabitants in 2010. The argument is that recovering materials from USW is aligned to sustainable development concept, however there is a lack of a deeper sustainability assessment, raising doubts about the benefits received by society on recovering materials. In this sense, emergy accounting (spelled with “m”) suggests to be a good alternative when assessing these benefits under a global scale. The aim of this work is to assess the São Paulo's SCWTP using Emergy Accounting. Results shown that currently there is an emergy balance by sorting paper (ratio of recovered by invested emergy of 0.97), and an emergy benefit for iron&steel (2.65), plastic (2.91) and compost (2.57). However, there is an emergy cost by sorting glass (0.23) and aluminum (0.20). A plausible scenario by increasing the recovering efficiency of glass from current 11.6% to 52.9%, and aluminum from 4.7% to 24.7% (both in wet weight), results in an emergy benefit for all materials. The Net Emergy Benefit indicates the SCWTP as a better alternative when the total net emergy return to society is the focus, because while it makes available about 3.13E+14seJ/Mg of treated USW, the landfills have an average emergy deficit of −3.39E+13seJ, indicating that landfill uses more emergy than makes available. Results indicates that SCWTP must receive political incentives due to its good emergy performance and others social beneficial aspects, however, aiming to improve the overall performance, each individual citizen must collaborate with waste reduction and the separation of non-organic material from the organic ones at origin.
Annarita Paiano | Giovanni Lagioia | Andrea Cataldo
Abstract: In the last twenty years, there has been a sharp increase in the consumption of commodities with a short life-cycle. This is especially true for electronic equipment such as mobile phones, which are the focus of this paper. The short lifespan, which is due to continually substituting obsolete equipment with newer and more innovative models, has stimulated the growth in sales of these electronic goods. Europe continues to be the main mobile phone market in developed countries, but this growth has slowed down over the last two years. Despite being an already mature market, Italy has a “diffusion rate” (i.e., the number of active lines per 100 inhabitants) higher than 146, which is the highest in the European Union.This scenario demonstrated the need for a study examining the sustainability of the mobile phone sector according to two critical aspects that are often due to the behavioural patterns of the users: the first is the energy consumption of mobile phones and their associated equipment, and the second is related to the conflicting link between potential dematerialisation due to the miniaturisation of the devices and the resource consumption and waste generated in this sector. This paper discusses these two critical aspects and presents an overview of the Italian mobile phone sector, particularly related to the energy consumption during the use phase and increase of mass flows due to the devices circulating in Italy and the higher amount of the disposable products that have to be managed.The results show that, in Italy, the entire mobile phone system consumes approximately 2200GWh per year, which is equal to 0.7% of the national electricity consumption, and produces potential e-waste from end-of-life devices totalling over 11 thousand tonnes for the period from 2007 to 2012. Concerning the issue of resources consumption, this estimate highlights that the potential savings in inputs, due to the reduction in device weight over time, has always been counteracted by their increasing demand.
Prashant Shirodkar | Yusuf Mehta | Aaron Nolan | Eric Dubois | Darren Reger | Leslie McCarthy
Abstract: Recent studies have consistently shown that RAP mixed with virgin binder and aggregates results in partial blending; that is, a phase between 100% blending and the “black rock” effect occurs. The impact of partial blending on new virgin binder content is apparent and may cause under-asphalting of mixture, resulting in poor pavement performance. Influence of partial blending on critical grade of RAP mixes and allowable percentages of RAP have not been evaluated. The purpose of this paper is to develop the blending chart for different degrees of blending to study the impacts of partial blending on the critical grade of blended binder. To achieve the objective, blending charts for 100%, 70% and 50% degree of blending have been developed for PG 70-28 and PG 58-28 binder by mixing virgin and RAP binders in differing proportions. The higher critical grade of blended binder does not change for different degrees of blending (70% and 50%) for low percentages of RAP binder (25% and 35%) with PG 70-28 binder. However, for high percentages of RAP binder (50%) and low degree of blending (50%), higher critical grade of blended binder can cause grade change.
Felipe Ramalho Pombo | Alessandra Magrini | Alexandre Szklo
Abstract: This study assesses the application of rationalization techniques in oil refineries to preserve freshwater resources. These techniques include conservation, recycling and reuse of water and Pinch technique. Several refineries in the world use treated household wastewater. In Brazil, a country with expanding refining capacity, this practice is planned for two refineries. Water conservation and recycling initiatives also hold promise, including reduction of losses, replacement of cooling towers with smaller units and recycling of blowdown into cooling towers and steam generation systems. Some technologies gain importance for wastewater reuse, such as ion exchange, nanofiltration and advanced oxidative processes. Finally, the application of the Pinch technique reduces the withdrawal of water and its associated costs. Thus, this method is appropriate in areas with scarce water, where some new Brazilian refineries are slated for construction.
Quantifying the impacts of primary metal resource use in life cycle assessment based on recent mining data
Pilar Swart | Jo Dewulf
Abstract: The quantification of impacts in the abiotic resource category in life cycle assessment is still controversial. However, this is a pertinent issue because of the growing dependence of our industrial society on these resources, particularly on metal resources. One of the important shortcomings of the existing assessment methods used today is that characterization factors are not based on actual mining practice data. In this paper, a new characterization factor derived from recent (1998–2010) and representative (more than 50% coverage of global primary metal production) mining data was established for nine metals: copper, zinc, lead, nickel, molybdenum, gold, silver, platinum and palladium. The quantification of this new characterization factor is based on the annual increase in mass of ore required per unit mass of metal in the ore. This quantification relies on the concept that the mining of resources is threatened not by lack of ores but by changing ore characteristics, e.g., the percentage of metal in the ore, mineral type and location. The characterization factors determined in this study ranged from below 0.1kgorekg−1y−1 for zinc to more than 15,000kgorekg−1y−1 for gold. These results indicate that in 1999, 370,000kg of ore was required per kg of gold in the ore, whereas in 2008, 530,000kg of ore was required per kg of gold in the ore (an increase of approximately 4% per annum). When comparing these results with traditional life cycle impact assessment methods, it was found that in all but one method gold, palladium and platinum have the highest characterization factors among the nine metals. In all methods based on ore grade changes lead and zinc are the metals with the lowest characterization factors. However, an important difference in the proposed method is that it assigns higher relative values to precious metals. This suggests that the supply of precious metals may be under more pressure than indicated by other methods, which in the framework of the proposed method implies greater efforts in mining and mineral processing. There is still scope for improvement of the proposed method if more data become readily available.
Door-stepping as a strategy for improved food waste recycling behaviour – Evaluation of a full-scale experiment
A. Bernstad | J. la Cour Jansen | A. Aspegren
Abstract: Comparisons were made between two groups of households in a multi-family residential area in order to investigate how oral information through a door-stepping campaign can influence household food waste recycling behaviour from a quantitative as well as qualitative perspective. Source-separation behaviour was assessed both through weakly weighting of all source-separated food waste and dry recyclables as well as residual waste generated over a period of 104 weeks, as well as repeated waste composition analyses. Introduction of source-separation of food waste for biogas production significantly decreased the generation of residual waste in the whole case-study area. An average generation of 0.72 and 0.71kg, household−1, week−1 of separately collected food waste was found amongst households receiving and not contacted through the door-stepping campaign respectively. The difference between the groups was not statistically significant. Four waste composition analyses show that the average source-separation ratio of food waste was higher and the ratio of incorrectly sorter material lower in the food waste fraction amongst households where oral information had been provided. A decrease over time in the source-separation ratio of food waste amongst households receiving oral information suggests a low durability of the door-stepping campaign. No signs were seen of increased source-separation ratio or decreased ratio of incorrectly sorted material amongst dry recyclables. The study supports previous findings pointing at accessibility as a key factor for increased recycling behaviour. However, results also suggest that such systems must address convenience also in the household interior.
Moving down the cause-effect chain of water and land use impacts: An LCA case study of textile fibres
Gustav Sandin | Greg M. Peters | Magdalena Svanström
Abstract: Environmental impacts of water and land use are often omitted or treated in an over-simplified manner in life cycle assessments (LCAs). This may provide insufficient foundation for LCA-based decision-making when product life cycles include agriculture or forestry.The aim of this paper is to assess water and land use impacts of biobased textile fibres and contribute to the development of methods for characterising such impacts in LCA. This was done by applying and developing methods suggested in literature to an LCA case study of a wood-based textile fibre under development. The water use assessment method considers water deprivation at the midpoint level and the impact on human health, ecosystem quality and resources at the endpoint level. The land use assessment method measures the impact on biodiversity, by considering changes in the vascular plant species richness and the vulnerability of the surrounding ecosystem.In the case study, five wood-based fibre production scenarios were set up in order to account for uncertainties in the future location of operations. For comparison, two cotton production scenarios were set up.An innovative consequential approach was applied in the inventory analysis of water use, in order to capture the system-scale effects of how forestry and cotton farming influence the hydrological cycle. This was compared to a more traditional attributional approach.The results show that the location of operations influences water use impacts, as water extracted from relatively water stressed environments leads to higher impacts. Furthermore, for some scenarios, the result differed considerably between the consequential and attributional inventory approaches. Moreover, it is shown that the consequential approach adds the possibility of recognising increased runoff as a potential benefit of certain types of land use.Biodiversity impacts from the transformation of natural land are much higher than impacts from the occupation of land. If transformation of land takes place, and all impact is allocated to the first harvest, cotton production appears to have a particularly high impact. However, if the transformational impact is allocated over several subsequent harvests, the impact of cotton and wood-based fibres becomes more similar. How to handle this allocation problem deserves further attention in the development of characterisation methods for land use impacts.The study has contributed to the development of characterisation methods by developing a water use inventory approach and by illuminating several methodological aspects of both water and land use impact assessment which need further research.
Ali O. Atahan | Ayhan O. Yucel
Abstract: This paper summarizes results of an experimental study intended to evaluate performance of recycled content sign posts. A total of 23 sign posts, circular, rectangular and square shaped, obtained from 13 different manufacturers were evaluated using laboratory and field tests. Full-scale specimens were used in order to account for size effects and the non-homogeneous nature of the materials. Static tests, such as flexure, hydrothermic cycling, density, creep, warpage and dynamic pendulum impact tests were used to make conclusive decisions regarding their suitability. Conventionally used wooden sign post was also included in the experimental program to provide baseline performances for the material evaluation. Static and dynamic test results demonstrated that some recycled sign posts could be suitable alternatives to conventional wooden post. Full-scale crash testing is strongly recommended to substantiate experimental findings.
Zhong Li | Gordon Huang | Yimei Zhang | Yongping Li
Abstract: In this study, an inexact two-stage stochastic credibility constrained programming (ITSCCP) method is developed and applied to the water quality management system. It incorporates the credibility constrained programming, two-stage stochastic programming and interval programming within an optimization framework, so that uncertainties expressed as intervals, probabilistic and possibilistic distributions can be effectively communicated. The study area is the Xiangxi River Basin of the Three Gorges Reservoir (TGR), the largest reservoir in China. The significant advantage of the ITSCCP water quality management model is that it can reflect the tradeoffs between the predefined economic targets and the associated environmental penalties, as well as the fuzziness of the pollution load capacities. Stable interval solutions can be obtained by using the two-step interactive solution algorithm. A spectrum of potential pollution abatement options with varied levels of system-failure risk can be generated. The resulting solutions show that the proposed method can provide scientific bases for water quality management and other environmental systems problems.
Greenhouse gas emissions and energy balance of sunflower biodiesel: Identification of its key factors in the supply chain
Alfredo Iriarte | Pablo Villalobos
Abstract: The production of first generation biofuels, such as sunflower-based biodiesel, is potentially an option for diversifying the energy matrix in several South American countries. However, biofuels present environmental challenges, especially concerning the reduction of greenhouse gas (GHG) emissions. This study, using a life-cycle approach, evaluates the GHG emissions and energy balance of the future nationwide production of sunflower-based biodiesel in Chile. Direct land use change is included in the analysis. The overall findings indicate that sunflower biodiesel, under the most likely production conditions, will have better environmental performance than fossil diesel in terms of both indicators. The agricultural stage is associated to key factors such as land use change, and nitrogen fertilizers. These factors contribute significantly to GHG emissions or energy demand in the biodiesel life cycle. The sensitivity analysis shows that no GHG emission saving could occur if nitrogen fertilizers rate exceeds 330kgN/ha. In order to reduce the environmental impacts of this biofuel, improvement measures are suggested.
Y. Pontikes | G.N. Angelopoulos
Abstract: Utilisation of Bayer's process bauxite residue, BR, aka red mud, takes place in a very small fraction worldwide, most probably <5wt.%. A success story in terms of industrial implementation is utilisation of BR as a raw material in cement production. The use of BR as a pozzolanic material has also been reported, with promising results in laboratory scale. This work aims to present an in depth review of these cases by providing a critical overview of the on-going research over the last forty years. To facilitate the transition from laboratory to industrial scale, a barriers and drivers analysis is also presented for the case of BR addition in the raw meal of cement clinker, following both BR and cement producers’ perspective. It is demonstrated that tangible results can be achieved with present-day technology and that one of the major barrier is economic. A number of clear actions are suggested to accelerate the transition towards a more sustainable management of BR.
Martin Koller | Daniel Sandholzer | Anna Salerno | Gerhart Braunegg | Michael Narodoslawsky
Abstract: Life cycle assessment (LCA) has turned into a powerful tool to critically and straightforward assess the holistic impact of bio-based plastics and other bio-based products. In order to assure at the same time ecological soundness and to support the economical success of a bioproduct, an early assessment already in the stage of product development is needed. This strategy helps to identify and subsequently to avoid ecological “hot spots”. Assessment by using the sustainable process index (SPI), a member of the ecological footprint family, is considered as an especially viable strategy to realize this goal. The software SPIonExcel was developed to make the assessment methodology easily applicable and operator-friendly.During the process of development for archaebacterial production of poly(hydroxyalkanoate) (PHA) biopolyesters from the industrial surplus material whey, a SPI assessment was accomplished to optimize the process in terms of ecological sustainability. As the major outcome, the resulting ecological footprint was comparable with that of competing fossil plastics. Additionally, optimization potentials to further increase the ecological competitiveness were highlighted and quantified. In addition, the developed PHA production process was compared with production of whey powder as the competing, conventional application of surplus whey. Also in this case, the novel PHA production process was superior according to the SPI calculations.
On-site rainwater harvesting to achieve household water security among rural and peri-urban communities in Jordan
Almoayied Assayed | Zaid Hatokay | Rania Al-Zoubi | Shadi Azzam | Mohammad Qbailat | Ahmad Al-Ulayyan | Ma’ab Abu Saleem | Shadi Bushnaq | Robert Maroni
Abstract: This paper presents the experience of Mercy Corps’ “Community Based Initiatives for Water Demand Management” project, a five year project (2006–2011), in terms of community-based initiatives for water management. This project was designed to build the capacity of local community-based organizations (CBOs) to raise the awareness level around water demand management (WDM) and engage community members in water management measures. It showed how local solutions decrease the reliance on public water systems and ultimately help in facing the water shortage on a national level. This paper also showed that on-site rainwater harvesting Cisterns funded through this project have been able to harvest 88,335m3 annually. The paper found that rainwater harvesting at household level was able to save an average of 24% in potable water per year.
Roz-Ud-Din Nassar | Parviz Soroushian | Tewodros Ghebrab
Abstract: Field investigation of high-volume fly ash (HVFA) concrete in pavement construction was carried out. Test results performed on cores drilled from pavement after 270 days of concrete age showed that use of HVFA results in production of pavement concrete with improvements in: strength; moisture barrier qualities; and abrasive resistance characteristics. These improvements are brought about by the pozzolanic reaction of fly ash with the hydrates of cement that favorably changes the microstructure and interfacial transition zone in the resulting concrete.Use of high volume of fly ash in pavement concrete as partial replacement for cement is estimated to produce major energy and environmental gains and is a practice that is aimed at producing durable and sustainable concrete-based infrastructure. The use of HVFA concrete can significantly economize the construction of concrete pavements and improve the service life of transportation infrastructure.
Assessment of residential rainwater harvesting efficiency for meeting non-potable water demands in three climate conditions
Mohammad Hossein Rashidi Mehrabadi | Bahram Saghafian | Fereshte Haghighi Fashi
Abstract: Global demand for clean water supplies is on the rise due to population growth. This is also true in most cities of Iran. Non-conventional water resources must be developed to partially offset the increasing demand. In this study, the applicability and performance of rainwater harvesting (RWH) systems to supply daily non-potable water were assessed. Storage of rain falling on the roofs of residential buildings and directed into installed tanks was simulated in three cities of varying climatic conditions, namely Tabriz (Mediterranean climate), Rasht (humid climate), and Kerman (arid climate). Daily rainfall statistics for a period of 53 years as well as the information on the contributing roof area, available tank volumes and non-potable water demand were collected in each city. Typical residential buildings with roof areas of 60, 120, 180 and 240m2 with an average of four residents in each house were considered for the study. According to the results in humid climate, it is possible to supply at least 75% of non-potable water demand by storing rainwater from larger roof areas for a maximum duration of 70% of the times. For roofs with small surface area, the supply meets 75% of non-potable water demand for a maximum duration of 45% of the times. Moreover, for Mediterranean climate, it is possible to supply at least 75% of non-potable water demand in buildings with larger roof areas for a maximum duration of 40% of the times. It is also found that in arid climate, similar duration is only 23% of the times.
Is PET bottle-to-bottle recycling safe? Evaluation of post-consumer recycling processes according to the EFSA guidelines
Abstract: For almost 15 years now in Europe, used plastic bottles made of polyethylene terephthalate (PET) have been recycled in such a way that the recyclate can be used for new PET bottles. Several recycling plants have been established all over Europe. Since May 2008 the European Recycling Regulation 282/2008 has been in force. According to this regulation, every recycling process must be individually approved by the European Food Safety Authority (EFSA). For this evaluation process, EFSA has developed a conservative evaluation concept in order to protect consumers. The evaluation is partly based on mathematical calculation of the migration. The current migration model overestimates the migration. EFSA acknowledges that the migration model overestimates by at least a factor of 5. This applies for small molecules such as toluene. However, higher molecular weight contaminants such as benzophenone are even more overestimated. The reason for this overestimation is that the currently used migration model is based on a fixed activation energy of diffusion. Conversely, the curve of the maximum bottle wall concentration calculated using the current migration model increases much too gradually with the molecular weight. New developments in migration modelling consider more precisely the activation energies of diffusion. Consequently, using the new, more realistic diffusion coefficients influences significantly the EFSA evaluation criteria.