John Carrell

An investigation of indicators for measuring sustainable manufacturing

This paper presents an investigation of sustainable manufacturing indicators in both industry and academia. While the concept of Sustainable Manufacturing has been brought up for a long time, little consensus has been researched so far with respect to how to define or measure it, especially in Economic and Social dimensions. This research tries to investigate current application status of sustainable indicators within U.S. manufacturing companies, and explore various views from academia in regards to weighting Economic / Social indicators through Analytic Hierarchy Process (AHP). The paper concludes with a summary of statistical results as well as recommendations for its further development and practical application.

Review and future of active disassembly

Disassembly has been widely accepted as a disadvantageous end-of-life activity, but with increasing pressures from directives, such as waste on electrical and electronic equipment, and with increasing pressures to become sustainable disassembly is becoming necessary. Current disassembly methods, including both manual and automated disassembly, need improvements to meet this necessity. This paper will introduce the improvements needed and suggest through literature the validity of active disassembly (AD) to provide these improvements. Past and current research will also be considered to provide a future path for AD. This future path for AD will consider a collaborative effort to solve problems with materials, environmental triggers and costs seen with AD.

Robust analysis of the active disassembly process

This paper explores a means to control the active disassembly (AD) process for designed and manufactured heat-activated shape memory polymer snap-fits. Testing was performed for demonstration of the active release of the SMP snap-fits and for analysis of AD control factors. Robust design methodologies with Taguchi methods were used to analyze the AD process factors, including heating method and disassembly temperature. The results from this research show the successful demonstration of the SMP snap-fits. AD process analysis shows that both the heating method and temperature affect the AD process. The analysis determines that by increasing the heat exchange rate the snap-fit disassembly time is shortened. From the performed experiments, it was seen that an Oil bath at 150°C produced the best results in regards to disassembly time and signal-noise ratio.

Improvement of home appliances design based on energy-saving concept: Case studies on hair dryer and coffee maker

World market energy consumption is projected to increase by 57% from 2004 to 2030. Worldwide efforts to meet these challenges include developing alternative energy sources, exploring renewable energy resources, and reducing energy consumption. In this paper, the authors presented a new design method for energy-saving product by means of two simple case studies, hair dryer and coffeemaker. The results show that the new design method is useful and applicable. However, there were some simplifications in the case studies, and further research need to be done by considering improving all the parts of the product.

A Binary Linear Programming Approach for LCA System Boundary Identification

One of the very first steps in conducting life cycle assessment (LCA) is system boundaries identification. A binary linear programming (LP) model is proposed to identify boundary between significant and insignificant processes in a LCA study. The proposed model is designed based on Relative Mass-Energy-Economic (RMEE) methodology. There are two types of objective function that can be solved by the proposed model, (1) to minimize number of processes considered in LCA or (2) to maximize cut-off criteria values. A numerical example and sensitivity analysis are provided to verify the applicability of the proposed model.

Use of an energy-saving concept to assess life-cycle impact in engineering

Energy and Environmental issues are worldwide concerns in the 21st century. The authors propose that the best way to solve the energy-use problem is to account for all of a products energy consumption information at the beginning of product design. Therefore, with the objective to promote energy-saving throughout the entire life cycle of general products or systems, the authors develop a new product design method by integrating the engineering design theory and two new concepts. A case study based on a typical energy-consuming product, a commercial hair dryer, will be presented in the paper for demonstrating the new design concept.

Shape memory polymer nanocomposites for application of multiple-field active disassembly: experiment and simulation.

Active disassembly (AD) uses innovative materials that can perform a designed disassembly action by the application of an external field. AD provides improvements over current disassembly processes by limiting machine or manual labor and enabling batch processing for end-of-life products. With improved disassembly operations, more reuse of components and purer recycling streams may be seen. One problem with AD, however, has been with the single-field actuation because of the probability of accidental disassembly. This presentation will discuss the application of shape memory polymer (SMP) nanocomposites in a new AD process. This novel AD process requires multiple-field actuation of the SMP nanocomposite fastener. In the analysis of this AD process, thermal and magnetic field tests were performed on the SMP nanocomposite. From these tests, finite-element analysis was performed to model and simulate the multiple-field AD process. The results of the simulations provide performance variables for the AD process and show a better performance time for the SMP nanocomposite fastener than for a comparable SMP fastener.

Disassembly efficiency improvements with active disassembly technologies

DISASSEMBLY is an advantageous end-of-life activity that can promote reuse, remanufacture, and purer recycling of a products subassemblies and components. The benefit of disassembly for small electronic products, such as modems, routers, and electric adaptors, has, however, outweighed by the processing costs because current disassembly methods require one-at-a-time processing. This limits disassembly for these products and thus limits the recovery of valuable materials and components from these products at end-of-life. Active disassembly (AD) has been a means to overcome this disadvantage by incorporating innovative fasteners and elements that can react with an outside stimulus to cause self disassembly of a product [1]. This in turn will allow for batch or mass processing of products for disassembly. This paper will thus focus on the benefits and efficiency gains in disassembly when products are fitted with AD fasteners. Seven electronic products that would normally not be disassembled at end-of-life are analyzed and their theoretical gains with AD are discussed.

An improved binary linear programming approach for life cycle assessment system boundary identification

According to ISO standards life cycle assessment (LCA) consists of goal definition and scoping, inventory analysis, life cycle impact assessment and interpretation. In goal definition and scoping LCA system boundary is defined. Since LCA is time consuming then there is a need for a systematic approach to determine which processes needed to be included in the system boundary. This paper fulfills the need by proposing an improved binary linear programming model for LCA system boundary identification. The objective function of the model is to minimize the number of processes included in the system boundary and its constraints are the specified mass, energy and economic value ratios. In order to demonstrate its applicability an example is presented. A sensitivity analysis is also conducted in order to illustrate how the change in the specified mass, energy and economic value ratio will affect current optimum system boundary.

Modeling of Heat Transfer in Shape Memory Polymer Nanocomposites

Diaplex MS5520, SMP Technologies, Inc. transition temperature 55°C, was filled with varying proportions (5 wt.%, 15.00 wt.%, and 25 wt.%) of magnetite nanoparticles, NanoArc and Iron(III) Oxide; 20–40 nm APS Powder from Alfa Aesar. The SMP nanocomposite was tested by thermomechanical methods, derived thermo-magnetic-mechanical methods, and shape memory methods. The results of such methods show an ability of the SMP nanocomposite to be controlled in shape deformation and recovery with an applied thermal then applied magnetic field. This paper focuses on the thermal field needed to help trigger the SMP nanocomposite. The objective of the study is to investigate the heat transfer characteristics of a SMP filled with magnetite nanoparitcles. A transient heat equation model is developed, and numerical simulation is performed in Sundance to show the underlying state of thermal change in recovery and deformation process. Result of the simulations roughly match those observed in the experiment.Copyright