Proceedings Volume 4193

Environmentally Conscious Manufacturing

cover
Proceedings Volume 4193

Environmentally Conscious Manufacturing

View the digital version of this volume at SPIE Digital Libarary.

Volume Details

Date Published: 9 February 2001
Contents: 12 Sessions, 43 Papers, 0 Presentations
Conference: Intelligent Systems and Smart Manufacturing 2000
Volume Number: 4193

Table of Contents

icon_mobile_dropdown

Table of Contents

All links to SPIE Proceedings will open in the SPIE Digital Library. external link icon
View Session icon_mobile_dropdown
  • Remanufacturing and Inventory Issues
  • End-of-Life Management
  • Disassembly
  • Life-Cycle Assessment
  • Management Issues
  • Supply-Chain Management and Information System
  • Environment Impact Assessment
  • Sustainable Product
  • ECM Design of Product and Processes
  • Fabric and Paper
  • Recycling of Construction Materials
  • Potpourri
  • Management Issues
Remanufacturing and Inventory Issues
icon_mobile_dropdown
Substitution policies for a hybrid system
As a consequence of environmental necessities, reuse of products has recently become an important issue for production and planning. Many companies are involved in retrieving used products, where they repair, refurbish and upgrade the products in order to sell them for profit. However, the regulations for many markets do not allow manufacturers to sell remanufactured products under the same pretence as new products. Therefore, companies are forced to differentiate both the recovery and the sales activities for the remanufactured products from that of the new products. In this paper, we study the impact of this differentiation. We particularly look at the feasibility of substituting one version of the product with the other in order to satisfy the demand. In the first phase of the study, we try to find optimal switching functions for substitution decisions using a Markov decision process. In the second phase, we define several control policies and compare them with respect to the expected total cost function of the system.
Life-cycle management for style goods inventory
Toyokazu Nose, Kenichi Nakashima, Hiroaki Ishii
When the life cycle of a product, material or service, studied in a Life Cycle Assessment (LCA) affects other life cycles not included in the system in analysis, it is necessary to apply allocation rules. Allocation can be defined, in LCA context, as the
Effect of reusable rate variation on the performance of remanufacturing systems
In this paper, we investigate the variation in the reusable rate of cores (used products) on the performance of the remanufacturing system. The remanufacturing system considered here consists of three modules; viz., the disassembly and testing module for returned products, the disposition module for non-reusable returns, and the remanufacturing module. Each server in the system is subject to breakdown and has a fmite buffer capacity. Repair times, breakdown times and service times follow exponential distributions. We model the remanufacturing system as an open queueing network and use the decomposition principle and expansion methodology to analyze it
End-of-Life Management
icon_mobile_dropdown
Disassembly and material recovery models for end-of-life electronics products
Bryan Reimer, Manbir Sodhi
In spite of growing environmental concerns about the disposal of mass produced products, there are few products which are economically viable to recycle. In general recycling results in an increase in product life-cycle costs. Increasing the efficiency of recycling operations will reduce the economic burden of recycling, thus providing an additional incentive for recycling. This paper presents models that consider the options of disassembly and material recovery for electronics products. Mathematical programming models, representative of the many choices for recycling are presented as well as a numerical illustration highlighting the use of the model for selecting the best recycling options.
Economics of PC recycling
Jane E. Boon, Jacqueline A. Isaacs, Surendra M. Gupta
As the use of personal computers (PCs) increases, their short life cycle and the fact that they contain many hazardous materials means that their retirement and disposal represents a significant environmental concern. Many communities are mandaling the recycling of these PCs, to recover parts and materials, and to minimize the amount of waste landfihled or incinerated. An industry to recycle these PCs is evolving to take advantage of this stream of materials. At present, PC recycling is not profitable. This paper investigates the factors that most influence the net cost to recycle PCs so that PC manufacturers, recyclers and legislators may better develop products and policies to insure that it is cost effective to recycle PCs.
Economic analysis of end-of-life computer systems in educational institutions
Mehmet Dincer, Elif A. Kizilkaya, Surendra M. Gupta
In this paper we address the operational and economical aspects of EOL computer systems at educational institutions. To this end we present an actual case study of a major university in Boston and provide an economical analysis of different options such as disposal, disassembly, recycling, reuse and re-sale of these systems. We recommend a new procedure that will improve the collection and handling processes leading to a structured decision making methodology.
Reuse of assembly systems: a great ecological and economical potential for facility suppliers
Hartmut Weule, Carsten Buchholz
In addition to the consumer goods, capital goods also offer a great potential for ecological and economic optimizations. In view of this fact the Project WiMonDi, started in September 1998, focuses to create a marketable Re-Use of modules and components of assembly systems by using modular design and organizationally closed distribution concepts. The objective of the project WiMonDi is to increase the usability and prolong the life span of assembly systems through the organized rebuilding of assembly facilities as well as the refurbishment and Re-Use of their components1. Therefore, it is necessary to develop organizational and methodical strategies and to initiate new distribution and user models between the supplier and user of assembly facilities to realize a workable Re-Use concept. WiMonDi is being conducted with tight cooperation between Industry and University.
Disassembly
icon_mobile_dropdown
Optimum disassembly sequence generation
Optimal disassembly sequences can be obtained on the basis of linear and mixed-integer programming methods. These are applied to models that are based on disassembly graphs. These graphs represent the possible subassemblies and the transitions (actions) between them. They represent the structure of the assembly in a more abstract manner than assembly drawings do. The translation from assembly drawings into graphs presupposes the selection of the feasible subassemblies and actions. In this contribution a method is discussed that supports the automatic determination of all possible subassemblies, starting from the assembly structure such as represented by drawings etc. It uses the connection diagram and a set of Boolean expressions that represent precedence relations. These are based on part removal in stead of on the disconnection of liaisons. Consequently, actions are transitions between subassemblies. Based on this method, feasible subassemblies and actions can be selected automatically. These represent the full set of data for the establishment of a disassembly graph. The method is demonstrated by the discussion of a number of assemblies that are taken from the literature. It appears that automatic selection of subassemblies is possible. Based on this selection, the set of actions can be defined and the disassembly graph can be established automatically.
Genetic algorithm for disassembly strategy definition
Claudio Caccia, Alessandro Pozzetti
The paper presents the application of a genetic algorithm to determine strategies for disassembly of products that have reached the end of their life. First, a general outline of the proposed methodology is provided and the features and specific properties of the genetic algorithm are described. Then an analysis of the algorithm’s behaviour is carried out based on different problems. Once product structure is acquired, feasible disassembly alternatives may be determined; the domain of solutions may then be analysed through the genetic algorithm. First of all, a ‘population’ of acceptable solutions is randomly generated; then these solutions are estimated based on the criteria of the highest recovery value and the minimisation of discharged parts: genetic mutation and crossover operators are applied to the current population in order to generate a new population as a substitute to the previous one. Some cycles are made estimating, each time, the goodness of each individual solution and its probability to ‘reproduce’ itself. At the end, the best-rated alternative becomes the solution of the algorithm. The solution of the algorithm is compared to the one provided by a ‘best-first’ algorithm (providing the optimal solution), for different types of products. In the paper, the efficacy of the proposed methodology is analysed, in terms of type of solution and computation time.
Life-Cycle Assessment
icon_mobile_dropdown
Integrated design strategy for product life-cycle management
G. Patrick Johnson
Two major trends suggest new considerations for environmentally conscious manufacturing (ECM) -- the continuation of dematerialization and the growing trend toward goods becoming services. A diversity of existing research could be integrated around those trends in ways that can enhance ECM. Major research-based achievements in information, computation, and communications systems, sophisticated and inexpensive sensing capabilities, highly automated and precise manufacturing technologies, and new materials continue to drive the phenomenon of dematerialization – the reduction of the material and energy content of per capita GDP. Knowledge is also growing about the sociology, economics, mathematics, management and organization of complex socio-economic systems. And that has driven a trend towards goods evolving into services. But even with these significant trends, the value of material, energy, information and human resources incorporated into the manufacture, use and disposal of modern products and services often far exceeds the benefits realized. Multi-disciplinary research integrating these drivers with advances in ECM concepts could be the basis for a new strategy of production. It is argued that a strategy of integrating information resources with physical and human resources over product life cycles, together with considering products as streams of service over time, could lead to significant economic payoff. That strategy leads to an overall design concept to minimize costs of all resources over the product life cycle to more fully capture benefits of all resources incorporated into modern products. It is possible by including life cycle monitoring, periodic component replacement, re-manufacture, salvage and human factor skill enhancement into initial design.
Streamlining environmental product declarations: a stage model
Elisabeth Lefebvre, Louis A. Lefebvre, Stephane Talbot, et al.
General public environmental awareness and education is increasing, therefore stimulating the demand for reliable, objective and comparable information about products’ environmental performances. The recently published standard series ISO 14040 and ISO 14025 are normalizing the preparation of Environmental Product Declarations (EPDs) containing comprehensive information relevant to a product’s environmental impact during its life cycle. So far, only a few environmentally leading manufacturing organizations have experimented the preparation of EPDs (mostly from Europe), demonstrating its great potential as a marketing weapon. However the preparation of EPDs is a complex process, requiring collection and analysis of massive amounts of information coming from disparate sources (suppliers, sub-contractors, etc.). In a foreseeable future, the streamlining of the EPD preparation process will require product manufacturers to adapt their information systems (ERP, MES, SCADA) in order to make them capable of gathering, and transmitting the appropriate environmental information. It also requires strong functional integration all along the product supply chain in order to ensure that all the information is made available in a standardized and timely manner. The goal of the present paper is two fold: first to propose a transitional model towards green supply chain management and EPD preparation; second to identify key technologies and methodologies allowing to streamline the EPD process and subsequently the transition toward sustainable product development.
Application of LCA method to an emergency lamp 626 Autotest Beghelli
Paolo Neri, Patrizia Buttol, Gabriele Danielli, et al.
This study was performed jointly by ENEA (Italian National Agency for New Technologies, Energy and Environment), Bologna and Florence Universities and the firm BEGHELLI1. The system function to be studied is the lighting of a room where a blackout has occurred. The functional unit is an emergency lamp manufactured by BEGHELLI, provided by a fluorescent tube and an accumulator battery with lead elements. The lamp life lasts 10 years. LCA is obtained by using the SimaPro 3.1 code and two methods: Eco indicator 95 with the normalisation weight ascribed to 10 years and a new method obtained by enclosing into the Eco – indicator 95 method some new damage categories such as some raw material depletion, solid and energy. The results show that the accumulator battery, the structure of the lamp and the electronic board are the components with greater environmental damage and the electrical energy for use produces 31% of total damage calculated by the Eco - indicator method. The most important categories of damage produced by accumulator battery are acidification due to material production and heavy metals due to disposal treatment of lead, and the ones produced by electronic card are acidification and winter smog due to copper production. To reduce the damage of emergency lamp some new solutions have been proposed. Finally the characteristics to obtain emergency lamp Ecolabel have been proposed.
Life-cycle assessment of an axial air compressor manufactured by the firm Fini Compressori
Paolo Neri, Patrizia Buttol, Marco Cremonini, et al.
This study was performed jointly by ENEA (Italian National Agency for New Technologies, Energy and Environment), Bologna and Florence Universities and the firm FINI COMPRESSORI. The functional unit is an axial air compressor manufactured by FINI COMPRESSORI, lubricated, having a 25-litres air tank, provided by 1.8 kW electrical motor. The system boundaries include raw material extraction and the end of life of the compressor. All metallic materials have the recycling as waste scenario. The LCA is obtained by using the SimaPro 3.1 code and the two methods Eco-indicator 95 and Ecopoints. The results show that air tank and stator of electrical motor are the components with greater environmental damage, even if the damage is mainly due to the electrical energy consumed during use. The most important categories of damage produced by the air tank are carcinogenic substances, heavy metals and acidification due to the material and processes used for its manufacturing and the ones produced by aluminium part of stator are acidification and winter smog due to material manufacturing. To reduce the damage of air compressor we have proposed some design solutions to lower air temperature in cylinder and at collector outlet.
Allocation of environmental loads in recycling: a model based in the qualitative value of recycled material
Jose Vicente R. Ferreira, Idalina Domingos, Paula Antunes
When the life cycle of a product, material or service, studied in a Life Cycle Assessment (LCA) affects other life cycles not included in the system in analysis, it is necessary to apply allocation rules. Allocation can be defined, in LCA context, as the act of assigning the environmental loads of a system to the functions of that system in proportionate shares. Most of the available allocation methods are of generic application and do not take into account the quality of the materials to be recycled. The few that do take quality into account attribute to it a quantitative value. Methods that are both generic and scientifically correct are generally difficult to apply. Rules that are simple enough for a case by case application could lead to LCA studies that cannot be compared. This way, the best will be to dispose of simple methods but fair and mathematically correct methods available with a fundamentally driven application to a sector of economic activity. In this study a method of allocation is proposed which takes into account primarily the "qualitative" value of the material to be recycled, irrespective of being a pos-consumption product/material or a secondary material of a production process. Through a case study, the potential of application of the proposed method is demonstrated, in the recycling of products coming from wood industries and its derivatives, when compared with other allocation methods.
Tool to incorporate environmental costs into life-cycle assessment
Senthil Kumaran Durairaj, Soh Khim Ong, Reginald Beng Hee Tan, et al.
The objective of this Life Cycle Environmental Cost Analysis (LCECA) model is to include eco-costs into the total cost of the products. Eco-costs are both the direct and indirect costs of the environmental impacts caused by the product in its entire life cycle. Subsequently, this LCECA model identifies the feasible alternatives for cost effective, eco-friendly parts/products. This attempts to incorporate costing into the Life Cycle Assessment (LCA) practice. Ultimately, it aims to reduce the total cost with the help of green or eco-friendly alternatives in all the stages of the life cycle of any product. The new category of eight eco-costs is being included in the cost breakdown structure. The mathematical model of LCECA aims to define the relationships between the total cost of products and the various eco-costs concerned with the life cycle of the products, and determine quantitative expressions between the above said costs. A computational LCECA model has been developed to compare the eco-costs of the alternatives. This model will include a break-even analysis to evaluate the alternatives, sensitivity and risk analysis modules. This model aims at a cost-effective, eco-friendly product as an end result. This LCECA model will be compatible with the existing LCA software tools.
Management Issues
icon_mobile_dropdown
Proactive environmental management of manufacturing companies
Karl-Werner Hansmann, Claudia Kroeger
This paper provides a production planning model considering reactive and proactive environmental management. Based on the traditional production planning model manufacturing companies that choose reactive environmental management, maximize their profit under consideration of emission standards for different pollutants. These state-defined standards are indicated by emission constraints that also include the possibility of investments in filters to reduce the emissions. Proactive environmental behavior leads to an objective function, which minimizes the emissions of the pollutants. Here, the impact of different pollutants is reflected by weights that can be fixed by the company and have a strong impact on the optimal solution. The paper will show under which conditions dual prices can be used as suitable weights.
Supply-Chain Management and Information System
icon_mobile_dropdown
Optimizing the supply chain in reverse logistics
Pitipong Veerakamolmal, Surendra M. Gupta
Supply chain planning systems in reverse logistics present the industry with new problems that demand new approaches. The specific problem ofthe reverse logistics for the end-of-life (EOL) products addressed in this study is to detennine the number of products to disassemble in a given time period to fulfill the demand of various components during that and subsequent time periods. We present a mathematical programming based model to solve the problem. When the problem is solved, it gives the number and thning of each product type to be disassembled in order to fuffill the demand of components needed at minimal disassembly and disposal costs. We illustrate the solution methodology with a case example.
Goal programming approach to the remanufacturing supply-chain model
The current trend of depletion of natural resources due to an ever-increasing number of consumer goods manufactured has led to an increase in the quantity ofused and outdated products discarded. From an environmental point ofview, it is not only desirable to disassemble, reuse, remanufacture and/or recycle the discarded products, in many cases it can also be economically justified. This situation being the motive, in recent years there have been several studies reported on disassembly, remanufacturing and/or recycling environments. Since "environmentally conscious manufacturing" is a relatively new concept that brings new costs and profits into consideration, its analysis cannot be provided by readily available techniques. This paper presents a quantitative methodology to determine the allowable tolerance limits of planned/unplanned inventory in a remanufacturing supply chain environment based on the decision-maker's unique preferences. To this end, an integer goal-programming model that provides a unique solution for the allowable inventoiy level is presented. The objective of the supply-chain model is to determine the number of a variety of components to be kept in the inventoiy while economically fulfilling the demand of a multitude of components, and yet have an environmentally benign policy of minimizing waste generation. A numerical example is presented to illustrate the methodology.
Disassembly knowledge representation via XML
Extensible markup language (XML) is a new powerful technique for Web and Internet development. It is a method of defining structured data in a text file. XML is expected to do for data what HTML has done for Web pages. XML's stiength lies in its simplicity to represent data and knowledge. It can maintain hierarchical structures encountered in many systems including assemblies and disassemblies. It can also be well integrated with Java, and its Java beans. Its strength lies in its flexibility to adapt to any knowledge domain because it is a metalanguage. It is used to develop modeling languages that are tailored to specific knowledge, and specific data structures and hierarchies. This paper presents an overview of XML, followed by a proposal of an XML-based knowledge representation model for disassembly planning. An example is used to demonstrate the capabilities ofthe proposed XML model.
Case-based reasoning disassembly system
This paper presents a new approach to address the problem of Planning for Disassembly (PFD). The approach is based on the Case-based reasoning technique. To assist planners to solve PH) problems, a system must have some heuristics and domain specific knowledge, which is related to the representation of the disassembly knowledge. In previous work, the authors suggested to use EMOPs (Eposodic Memory Organization Packet) for the knowledge representation of the PFD plan. This paper demonstrates the implementation of the EMOP memory model. The model has been implemented in C++, and tested. An example is presented to demonstrate the capabilities of the memory model.
Environment Impact Assessment
icon_mobile_dropdown
Ecoefficiency: how data envelopment analysis can be used by managers and researchers
Ecoefficiency is critical for organizations that seek to be both environmentally conscious and profitable. Ecoefficiency supports and aids in determining "win-win" strategies for organizations. Studying and managing organizations from this perspective requires an evaluation of ecoefficiency. To aid researchers and managers develop measures for ecoefficiency we review the use of data envelopment analysis (DEA) for this purpose. DEA theory and application have gone through major growth. Yet, its use as a tool for environmental performance evaluation has been limited. In this paper we provide a number of DEA models and some extensions and how they can be utilized from both the practitioner and researcher perspective. An illustrative example from published data helps to gain insight into the various models, their capabilities and limitations.
Methodology to assess the environmental impact of a product and its processes
K. Ravi Kumar, Dongwon Lee, Arvind Malhotra
This study presents a methodology for capturing the environmental impact of a product and its processes throughout the life cycle in discrete part manufacturing. The objectives of the study are to identify opportunities to enhance environmental friendliness of a product in its design stage, and assess whether the environmental impact has actually been reduced or has simply been shifted elsewhere in the life cycle of the product. Using the bill of materials and the process route sheet, we build the environmental status of its operations as a vector of measurable attributes, categorized under the taxonomy of social, ecological, and economic impact that can be aggregated and evaluated at a business unit level. The vector of social impact deals with the effects of materials used and wastes produced on people through the life cycle. The vector of ecological impact consists of effects of recycling, reuse, and remanufacturing of a product based on the notion of materials balance. Finally, the vector of economic impact represents the conversion of the previous two vectors into managerially relevant costs to firm expressed in dollar amounts so that managers in any positions visually appraise their operations and communicate each other with the same language.
Measuring business performance using indicators of ecologically sustainable organizations
Charles G. Snow Jr.
The purpose ofthis paper is to explore the use ofecology-based performance measures as a way ofaugmenting the Balanced Scorecard approach to organizational performance measurement. The Balanced Scorecard, as proposed by Kaplan and Norton, focuses on four primary dimensions; financial, internal-business-process, customer, and learning and growth perspectives. Recently, many 'green' organizational theorists have developed the concept of "Ecologically Sustainable Organizations", or ESOs, a concept rooted in open systems theory. The ESO is called upon to consider resource use and conservation as a strategy for long-term viability. This paper asserts that in order to achieve ESO status, an organization must not only measure but also reward resource conservation measures. Only by adding a fifth perspective for ecological dimensions will the entity be truly motivated toward ESO status.
Environmental impact assessment model for manufacturing processes
ChanPang Li, I.K. Hui
Environmental work in industry is considered as a strategically important issue. This is mainly driven by the social concerns about environmental impacts on human health and ecological system. A number of methods for the evaluation of environmental impacts have been proposed, but their considerations have only been given to either human health or ecological health. This paper presents a model to evaluate the potential environmental impacts on both ecological and human health of a manufacturing process. Five impact groups are used as the basis for the computation of the hazard values of ecological health. On the other hand, the hazard values of human health are based on the toxicological, cancer and physical effects of waste components. The model has been developed into a computer software, and its effectiveness has been demonstrated by a case of manufacturing process.
Sustainable Product
icon_mobile_dropdown
Surface cleaning substitutability in manufacturing organizations: an exploratory study
Sejal P. Shah, Joseph Sarkis
Clean manufacturing, pollution reduction, and waste minimization, have been in the limelight for the past decade as the best way to achieve industrial environmental. This paper reports the findings of an exploratory survey conducted of seven companies in the Central Massachusetts Region that have made the decision to approach the Surface Cleaning Lab (SCL or SCLab) of the Toxics Use Reduction Institute (TURI) seeking a substititte for toxic chemicals they currently use. We examine the factors associated with the decision to approach the SCL, and the factors associated with the decision to implement the recommendation of the SCL. The strongest factors in their final decision to seek a substitute are regulatory in nature, as reported by the six companies. Only one of the seven companies reports implementation of the recommendations made by the SCLab. The main determining factors for not implementing the recommendation were those associated with the quality of the substitute recommended, and employee satisfaction. This is one of the few studies that investigates motivational factors for substitutability for environmentally sensitive purposes.
Artifact System (AS) framework: a study of the coevolution of technological artifacts
Rahul Rai, Venkat Allada
The paper attempts to lay a foundation to understand and address the system level issues of sustainable product development. It is often emphasized that creating products on the basis of function/need and redefining product systems are the most important aspects of sustainable product development; however, no systematic approaches exist to adequately address these issues. We hypothesize that it is the epigenetic effect of artifact (interactions with other artifacts, environment, etc.) that produces a web structure among artifacts. This web structure (known as artifact system (AS)) has its own laws and rules of evolution. Appropriate design and realization of AS (i.e., constructive intervention of AS’s laws) will significantly promote sustainable product development. Specifically this paper addresses two issues: (1) The development of AS and discussion about how it is related to sustainable product development, and (2) A simulation model to study the distribution of artifact in AS and its implications on sustainable product development. The simulation methodology is elaborated through an example to emphasize the importance of AS framework to study sustainable product development. Finally, our preliminary results of simulation indicate that in every AS only few artifacts are dominant. This result points out that controlling the behavior of these dominant artifacts should be the prime focus of the sustainable product development efforts.
VerdEE: a new tool for the adoption of life-cycle assessment in small- and medium-sized enterprises
Paolo Masoni, Emanuela Scimia, Balazs Sara
Data and time requirements and complex methodological problems of a detailed Life Cycle Assessment (LCA) are wellknown and discussed. Its application has specific difficulties in Italian Small- and Medium- sized Enterprises (SMEs) where environmental information is generally dispersed, a short-term problem-oriented environmental management approach is common and dedicated human resources are usually missing. As a consequence, a new procedure specifically designed for SMEs, VerdEE (Verifica dell’Eco-Efficienza - Verification of Eco-Efficiency), was developed and implemented on an interactive CD-ROM. It is based on the following criteria: relying on a life cycle approach; aimed at evaluating the environmental profile of a product and at identifying improvement opportunities; sufficiently simple to be applied in a limited time; containing as much quantitative information as possible to make it usable by a non-expert user. The VerdEE procedure includes four main steps: "Goal and Scope definition"; semi-quantitative "Inventory"; "Check-list"; visualisation of results in "Matrix" and "Target-plot" form. The procedure is supported by an interconnected informative part about advantages of the life cycle approach for SMEs, principles of eco-design and environmental concerns.
Environmental aspects in product development: an investigation among small- and medium-sized enterprises
Sophie H. Byggeth, Goeran Broman
Small- and Medium sized Enterprises (SMEs) represent a large part of industry. Environmental considerations during product development in SMEs therefore imply a large potential for reducing society’s environmental impact. Implementing environmentally adapted product development among SMEs has been considered difficult and is uncommon. Our approach is to develop a qualitative Method for Sustainable Product Development (MSPD) that relates both to a framework for sustainability and to the ordinary product development process. The aim is to guide the user to avoid problems related to social and ecological non-sustainability without demanding extensive expertise knowledge. Two surveys in ten Swedish SMEs have been carried out. An initial survey registered their product development procedures and environmental work as well as desired characteristics of a new suggested method for integrating environmental aspects into the product development process. A second survey registered additional desired characteristics and improvement suggestions when testing an early version of our MSPD. The surveys and the structure of our MSPD are presented, and the desired characteristics for a workable method in SMEs, found in our investigation and in literature, are discussed.
ECM Design of Product and Processes
icon_mobile_dropdown
Environmentally conscious redesign of turbine blade fixtures
John J. Bausch III
This paper examines the re-design of turbine blade fixtures for the plasma spray coating process. The plasma spray process is used to apply a ceramic coating to turbine blades prior to gas turbine engine assembly. Without the ceramic coating, the blades would fail under the high temperatures produced during combustion. As a result, the plasma spray process is essential to modern gas turbine engines; the process as is stands, however, is environmentally expensive. Turbine blade holding fixtures are an integral part of the coating process, to both hold the blades within the furnace, and to protect precision assembly features on the root section of the turbine blade. In addition to the fuel costs and safety problems associated with the high temperature furnace, an environmentally hazardous acid bath is used to strip the ceramic coating from the fixtures to allow reuse. This acid bath is costly in terms of both production and the environment. The fixture redesign examines the functionality of the existing fixture design using a combination of classical, design for manufacturing, and axiomatic design methodologies, and develops a new design to eliminate the need for the acid bath. The new design also improves the productivity and safety of the plasma spray coating process. A prototype for the new design has been constructed and tested. The paper also discusses the economic benefits of the improved fixture design.
Evaluation of product design in environmentally conscious manufacturing
Alejandro Rivera-Becerra, Li Lin
This research presents an evaluation method to support design decision-making early in the design stage. The method is aimed at solid consumer products, and incorporates our previous work on Environmental Consciousness Criteria (ECC). A framework is defined as the foundation for the problem analysis, consisting of four mapping schemas connecting the product to the natural environment. We approach the problem of designing an environmentally conscious product as that of making decisions to incorporate the ECC as design progresses from the conceptual to the preliminary to the parametric design phases. A methodology is developed whose focus is on both the material properties and the geometric features of the product, and on how these impact the product's disposal stage. The method uses fuzzy methods and Multi Attribute Utility Analysis (MAUA). It is able to accommodate the varying degrees of uncertainty and availability of information, as well as other criteria such as cost. An analysis of cost implications from recovery is presented also. Application of this decisionmaking method will assist designers in maintaining environmental leadership in product development beyond the manufacturing stage.
Complications in disassembly line balancing
Askiner Gungor, Surendra M. Gupta, Kishore Pochampally, et al.
Disassembly line is, perhaps, the most suitable way for the disassembly of large products or small products in large quantities. In this paper, we address the disassembly line balancing problem (DLBP) and the challenges that come with it. The objective ofbalancing the disassembly line is to utilize the disassembly line in an optimized fashion while meeting the demand for the parts retrieved from the returned products. Although, the traditional line balancing problem for assembly has been studied for a long time, so far, no one has formally talked about the DLBP. In this work, our primary objective is to address the DLBP related issues. However, we also present a heuristic to demonstrate how several important factors in disassembly can be incorporated into the solution process of a DLBP. An example is considered to illustrate the use of the heuristic.
Planning end-of-life management within the product design process
Enrico Cagno, Augusto Di Giulio, Paolo Trucco
Product end-of-life management is a growing problem in all industrialised countries. The progressive shortening of the effective useful life as a result of technological obsolescence causes serious difficulties in ensuring adequate forms of disposal for the millions of products disposed each year. To date, two different approaches have been applied separately. On the one hand, disassembly and re-cycling technologies have been developed which are used when the product reaches the end of its useful life, while on the other, Design for Disassembly (DfD) and Design for Recycling (DfR) techniques have sought to provide features as early as the design phase which make it easier to dispose of or re-cycle products. Unfortunately a lack of consistence between disassembly/recyclability properties of products and actual end-of-life processes still be. The present paper describes and tests a new technique (ProEM -ProductEnd-of-Lfe Management Planning) for product end-oflife management planning from the design phase. Using an economic assessment model, ProEM identifies whether recycling/ re-use or disposal would be the preferable strategy by comparing the costs and earnings of re-cycling after disassembly with the cost of disposal in controlled tips. The validity of the model is tested in a case study of a refrigerator design based on DID techniques already introduced by the company.
Fabric and Paper
icon_mobile_dropdown
Reduction of colorants in nylon flock dyeing effluent
Qinguo Fan, Sunil Hoskote, Yuejun Hou
The batch dyeing of fiber materials such as staple fibers and flock is usually carried out by exhaustion methods. However, the dyeing of flock fibers, either nylon, PET or acetate, with acid or disperse dyes is not 100 percent efficient in terms of dye utilization. Optimally, only about 80 to 85% of the dyes used for dark shade in a dye bath can be exhausted onto the target fibers. Therefore, the remaining dyes in the spent dye bath are generally not reused and are usually discharged with minimum treatment, together with the dyeing chemicals into the sewage wastewater system causing environmental pollution. We are presenting technical solutions to reduce the colorants and chemical auxiliaries in the fiber dyeing effluents by: (1) optimizing the acid dyeing conditions such as salt addition and pH control; (2) reuse of the spent dye bath that remain after the original dyeing process. In the lab scale trials, we have successfully raised the acid dye exhaustion to over 90% by optimizing the dyeing conditions. The reuse of the spent acid dye bath also showed promising results with dye exhaustion ranging from 91 to 93% after 4 times reuse.
Improved crosslinking systems for high-quality fiber/fabric performance
Samuel C. Ugbolue, Steven B. Warner, Qinguo Fan, et al.
Crosslinking is a possible route for modifying fiber, fabric and polymer properties. Most of the crosslinking agents contain formaldehyde whose emissions into the air from textile materials have been limited to 0.1 mg/m3. Formaldehyde has irritant effect on the respiratory tract and mucosa in concentrations above 0.5 mg/m3 air and gives allergenic and sensitizing effect. Thus, several countries limit the formaldehyde content of textiles by law. The most widely used reactant resin in the textile industry is the DMDHEU (dimethyloldihroxyethyleneurea) which is based on reaction of glyoxal, urea and formaldehyde with cellulose by forming ether linkages under the influence of acid catalyst. Our research highlights an improved crosslinking system involving the use of considerably reduced formaldehyde, resulting in environmentally friendly processing flexibility, improved tenacity and toughness. This system is expected to provide crosslinks that can slide along the polymer backbone and cause the fiber to elongate under an applied load. The combination of enhanced tenacity and extensibility contributed to improved toughness, or work-to-failure properties.
Effects of technological developments in paper manufacturing and recycling: a case study of the Finnish pulp and paper industry
Sanna Poikkimaki
Technological development is seen as one of the fundamental forces in shaping the modern economies. The effects and the role of technological development are also central questions in many issues of environmental protection. This paper presents the results of a life cycle assessment study of the Finnish pulp an paper industry. Three comparative scenarios are drawn. Two scenarios describe the technological levels and production volumes of 1993 and 1997. A comparison scenario with the production volumes of 1997 and the technological level of 1997 describes the effects avoided by improvements. The results demonstrate that technological development has had considerable effects on the material flows of the industry within a relatively short period of time. Changes in most material flows result from various improvements. The environmental performance of the industry has been improved by both changes in operative practices as well as capital investments. The study fails to describe some aspects of realized developments and thus indicates that factors connected to technological change are highly problematic for LCA modelling.
Tradeoff between environmental impacts and economic benefits?: A case study of the Finnish and British pulp and paper industries
Mikko Valtonen
Due to the increased used paper collection rates in Western Europe, more recycled fibre will be used in the manufacture of paper. This will affect both the environmental and economic performance of the pulp and paper industry. The potential for the increase of the collection rate varies significantly in different countries in western Europe. In some countries the collection rate is already close to 70% (Austria, Germany) and in others it is around 45% (Italy, United Kingdom). With the increased demand for recycled fibre also the collection will increase. When the collection of waste paper is increased something has to be done with the collected paper. Different utilisation modes results in different emission profiles. They also have different economic consequences. In this article the environmental and economic impacts of an increased paper collection rate are studied with three alternative scenarios. These scenarios are drawn using a dynamic material flow modelling such as Joined Time Projection (JTP). The results show, that a clear trade off between harmful environmental impacts and economic benefits exists.
Recycling of Construction Materials
icon_mobile_dropdown
Recycling of manufactured waste shingles in asphalt paving mixes
Rajib B. Mallick, Walaa S. Mogawer, Matthew R. Teto, et al.
About 20,000 tons of manufactured waste asphalt shingles are being deposited in landfill every year in the state of Massachusetts. This has caused a shortage of precious landfill space, and significant increase in deposit fee. There is a need to evaluate the use of these waste shingles in hot mix asphalt, specially because the shingles contain significant amount of asphalt binder, and studies in some states have shown that use of shingles can result in savings, and improve hot mix asphalt performance. A laboratory study was conducted by the Worcester Polytechnic Institute and University of Massachusetts at Dartmouth, with a research grant from the Chelsea Center for Recycling and Economic Development. The results show that volumetric and low temperature property of hot mix asphalt with 3, 5 and 7 percent shingles are not significantly different from the properties of conventional hot mix asphalt used for surface courses. Standard deviation of test results for mixes with shingles are low, indicating consistency in the quality of the shingles. Mixes with 5 and 7 % shingles show significantly lower rutting potential compared to mix without any shingles. Hence, it seems that mixes with small amounts of shingles have the potential of savings as well as good performance. However, before any material can be used regularly, it must be evaluated under real-life production and construction conditions.
Reuse and recycling of construction and demolition material
Joseph P. Curro
Construction and demolition (C&D) activities are a major source ofbulky waste materials which take up valuable space in landfills. As the majority of landfills, particularly those in urban areas, are either fast approaching capacity, or are just not available, and as recycling has become a standard requirement in solid waste planning, a number of sorting and processing systems for C&D materials have been developed.
Sustainable development in the building industry: an analysis and assessment tool for design of disassembly
Carl-Alexander Graubner, Katja Reiche
Ecologically Sustainable Development (ESD) has been embraced by governments worldwide and as building plays a key role in development, it is implicated in this movement. Consideration of the whole life cycle of a building is a major aspect, when assessing its sustainability. While the reduction of operating energy and the optimization of building material selection has been a main focus of research in Europe, the consideration of maintenance during operation or the demolition of a building at the end of its life has usually been neglected. Aiming for sustainability the conversation of materials and energy by applying a closed system approach on a long term time scale must be realized. Therefore building materials are to be recycled, building elements are to be reused and buildings are to be more flexible. Designing to facilitate the disassembly of building elements is expected to be an improvement for sustainable buildings. A tool for the assessment of building elements has been developed that focuses on connection selection, its influence on material and energy flow, as well as the quality of building waste materials. The assessment of material production and erection processes, using Life Cycle Assessment is completed with a qualitative/quantitative classification of demolition processes, and disposal scenarios, considering environmental, economic and technical aspects. An analysis of floor elements has confirmed, that Design for Disassembly is very promising for the improvement of sustainable buildings but that improvement potentials can differ considerably. Details of the analysis tool developed and an analysis of building elements will be shown in this article
Application of life-cycle assessment (LCA) methodology for valorization of building demolition materials and products
Balazs Sara, Ernesto Antonini, Mario Tarantini
The VAMP project (VAlorization of building demolition Materials and Products, LIFE 98/ENV/IT/33) aims to build an effective and innovative information system to support decision making in selective demolition activity and to manage the valorization (recovery-reuse-recycling) of waste flows produced by the construction and demolition (C&D) sector. The VAMP information system will be tested it in Italy in some case studies of selective demolition. In this paper the proposed demolition-valorization system will be compared to the traditional one in a life cycle perspective, applying LCA methodology to highlight the advantages of VAMP system from an eco-sustainability point of view. Within the system boundaries demolition processes, transport of demolition wastes and its recovery/treatment or disposal in landfill were included. Processes avoided due to reuse-recycling activities, such as extraction of natural resources and manufacture of building materials and components, were considered too. In this paper data collection procedure applied in inventory and impact assessment phases and a general overview about data availability for LCA studies in this sector are presented. Results of application of VAMP methodology to a case study are discussed and compared with a simulated traditional demolition of the same building. Environmental advantages of VAMP demolition-valorization system are demonstrated quantitatively emphasizing the special importance of reuse of building components with high demand of energy for manufacture.
Potpourri
icon_mobile_dropdown
Disassembly problem and the blood-cracking decision process
Belarmino Adenso-Diaz, Fernando Moure, Manuel Rendueles, et al.
The selection of the optimal disassembly plan is a key problem in the design of many industrial processes, given its influence in the final cost of products. Design for disassembling is of increasing importance mainly due to environmental management and maintenance accessibility concerns. In this paper we study the selection of a good disassembly plan, based on the knowledge of initial separation costs for any couple of components. We have developed a rational way of evaluating the separation cost for any number of different components, based on the given binary costs. As recursive exploration of the solution tree is not a practical procedure for real problems, a heuristic approach was developed. This procedure was used to solve a real problem: the most convenient way of decomposing animal blood in slaughterhouses -a serious environmental concern- from an economic point of view, finally obtaining eatable proteins. This is converted into a disassembly problem, simply by considering blood proteins as the components of an assembly that must be separated into parts.
Use of shell chitin extracted from seafood processing waste in recycling of industrial wastewater
Yuegang Zuo, Jian Zhan, Nuno Costa
Chitin is an unbranched polymer of ?(1?4)-N-acetyl-D-glucosamine, and chitosan is deacetylated chitin derivatives. These polysaccharides are widely distributed in the shells of crustacea (lobster, crab, and shrimp), in the cuticles of insects, in the shells and skeletons of mollusks and in the cell walls of fungi. The shells of crab, shrimp and lobster, which are currently waste materials of the food processing industries, are the best available sources of chitin and chitosan. Due to their unique biological, physicochemical properties and abundance, chitin and chitosan have been found to have many exciting potential applications in medicine, food, and in wastewater treatment. The environmental applications of chitin and chitosan for clarifying water, recovering proteinaceous materials, removing lipids, grease, pesticides, PCB, toxic heavy metals and textile dye residues from industrial effluents and polluted water bodies have been reviewed. Some recent results on the mechanisms and kinetics for the adsorption of textile dyes on chitin have also been reported. The adsorption results showed that chitin adsorbs up to 7% of its weight in an azo dye, Orange (II), because of the interaction between the positively charged acetamido/amino groups in chitin/chitosan and negatively charge functional groups in the dyes. The data presented suggest that the application of chitin could solve several environmental problems at once for aquaculture, shellfishing and other industries.
Management Issues
icon_mobile_dropdown
Comparison between the environmental damages of two axial air compressors manufactured by the firm Fini Compressori
Paolo Neri, Giuseppe Bernardi, Patrizia Buttol, et al.
This study was performed jointly by ENEA (Italian National Agency for New Technologies, Energy and Environment), Bologna and Florence Universities and the firm FINI COMPRESSORI. A comparison is carried out between the environmental damages of two models (MK10 and MK94) of air axial compressors manufactured by FINI COMPRESSORI, with a volume of intaken air of 226 l/min, a power of 1.8 kW and a maximum pressure of 10 bar. The comparison is obtained by using LCA calculated by SimaPro 3.1 code and two methods: Eco-indicator 95 and a new method obtained by adding to the Eco-indicator 95 method other damage categories such as some raw material depletion, solid and energy. The system boundaries include raw material extraction and the end of life of the components and some special tools for manufacturing such as dies, moulds and shells. All metallic materials have the recycling as waste scenario. For LCA study we have considered the three components crankshaft, crankcase and valve plate for both the models, the air cooling conveyor for the MK94 and the surplus of consumed energy for the MK10. The conveyor decreases the temperature of air and therefore increases the compressor efficiency and reduces the electrical energy consumption during the use. From the LCA results, we can conclude that the introduction of the conveyor reduces the damage of MK10 model of 114.07 mPt and that the other modifications of the design increase the damage of MK10 model of 11 mPt. The damage of air compressor can be diminished by reusing crankshaft and crankcase. A design modification of the blades of the ventilator is proposed to avoid the conveyor.