The 22nd CIRP conference on Life Cycle Engineering A cost and resource consumption model for improving resource efficiency of configurable roll-to-roll processing
Please refer to published version for the most recent bibliographic citation information. If a pu... more Please refer to published version for the most recent bibliographic citation information. If a published version is known of, the repository item page linked to above, will contain details on accessing it.
UM3-LCE3-ISN: a methodology for multi-level life cycle environmental and economic evaluation of industrial symbiosis networks
The International Journal of Life Cycle Assessment, 2022
Life cycle assessment (LCA) and life cycle costing (LCC) are state-of-the-art methods used to hol... more Life cycle assessment (LCA) and life cycle costing (LCC) are state-of-the-art methods used to holistically measure the environmental and economic performance of industrial symbiosis networks (ISNs). Existing methodologies face a challenge in unifying LCA and LCC of an ISN in a single model that can disaggregate the network-level results to the entity and resource flow levels. This study introduces UM3-LCE3-ISN, a methodology for multi-level matrix-based modeling for life cycle environmental and economic evaluation of ISNs. The UM3-LCE3-ISN methodology is designed to conduct a process-based LCA and LCC of any ISN scenario. The methodology constructs a single matrix-based model that represents the physical and monetary flows of an ISN across the entire life cycle. The demand and price vectors in the model can be manipulated to produce LCA and LCC results of an ISN at the levels of the entire network, individual companies, and specific resource flows. A formalism is provided that outlines the steps for model construction and multi-level analysis. Verification of the model constructed can be done by producing scaled technology and monetary matrices of an ISN. UM3-LCE3-ISN is tested through a case study of an urban agri-food ISN comprising five entities engaged in open and closed-loop recycling. The case study results demonstrated that UM3-LCE3-ISN can be used to compute the life cycle environmental impacts and net present value of ISNs at the three different stakeholder levels. Only one matrix model was required for each scenario to compute the LCA and LCC results for multiple stakeholders through one computation as opposed to several computations in multiple separate models. UM3-LCE3-ISN can produce granular LCA and LCC results regarding specific waste-to-resource conversion processes within an ISN and their contribution to the environmental and economic performance of specific entities. Overall, UM3-LCE3-ISN is able to unify potential conflicting assumptions and data used by different models and obtain more holistic LCA and LCC results that are harmonized for stakeholders across different levels. The UM3-LCE3-ISN methodology can be applied in industrial symbiosis facilitation tools that allow diverse stakeholders such as policy-makers, urban planners, businesses, and product designers to operate on a common platform to determine the life cycle environmental and economic performance of an ISN from multiple perspectives of interest. This would allow diverse stakeholders to make holistic evidence-based decisions and strategies for developing ISNs in different sectors that enable a large-scale transition to a circular economy.
The indoor laboratory-scale microalgae culture was elevated to 50 liter in outdoor photobioreacto... more The indoor laboratory-scale microalgae culture was elevated to 50 liter in outdoor photobioreactors for the cultivation of an oil-rich microalga, Chlorella vulgaris ESP-31. Under phototrophic and photoheterotrophic conditions using CO2 and acetic acid as carbon source, respectively , the lipid productivity and lipid content obtained were 30-31 mg/L/d and 35-44%, respectively. The effect of inoculum sizes on the performance of biomass and lipid production under phototrophic cultivation was also investigated. The lipid productivity of C. vulgaris ESP-31 was further improved to 47.6 mg/L/d when a higher inoculum size of 0.70 g/L was used. Finally, to avoid severe contamination problem during outdoor cultivation in the summer time, a two-stage lipid accumulation strategy was employed. The results show that the proposed two-stage process was able to avoid the bacterial contamination and enhanced the lipid content and lipid productivity of Chlorella vulgaris ESP-31.
Life cycle assessment of single-use surgical and embedded filtration layer (EFL) reusable face mask
Resources, Conservation and Recycling, 2021
Background The outbreak of the COVID-19 pandemic has led to an unprecedented amount of face mask ... more Background The outbreak of the COVID-19 pandemic has led to an unprecedented amount of face mask consumption around the world. The increase in face mask consumption has brought focus to their environmental impact. To keep up with the increased demand for face masks, different variations of reusable face masks such as the embedded filtration layer (EFL) reusable face mask have emerged in the market. This study quantifies the environmental impact of the EFL reusable face mask and the single-use surgical face mask. Methods The life cycle assessment (LCA) study of the entire value chain from cradle-to-grave is applied to each face mask. Both face masks are evaluated over 1 functional unit (FU) of 31 12-h days for a single person. The ReCiPe method with the Hierachist perspective was applied. A total of nine impact categories as well as the generated waste of each face mask are evaluated. Results The results show that for 1 functional unit, the use of single-use surgical face mask and EFL reusable face mask will contribute 0.580 kg CO2-eq and 0.338 kg CO2-eq to climate change and generate 0.004 kg and 0.0004 kg of waste respectively. Conclusion Comparing both face masks, the EFL reusable face mask will have a lower emission of at least 30% in terms of the generated waste and the impact categories considered, except for water depletion, freshwater eutrophication, marine eutrophication, and human toxicity.
In industrial symbiosis networks (ISNs), there are multiple stakeholders involved that require di... more In industrial symbiosis networks (ISNs), there are multiple stakeholders involved that require different levels of environmental performance insight for specific organizational goals. Life cycle assessment (LCA) has been widely applied to holistically evaluate the environmental benefits of ISNs and identify burden shifts. Representing ISNs in LCAs is complex due to resource flows with multiple sources and sinks and inter-company waste-to-resource exchanges. Furthermore, existing LCA methodologies face challenges in using one model for multi-level analysis to provide the network, entity, and resource flow-level perspectives of LCA results. To address these challenges, this study introduces M 3-IS-LCA, a methodology for multi-level matrix-based modeling and analysis of the life cycle environmental impacts of ISNs. A formalism is outlined for constructing the model and analyzing the model so that LCA results can be provided at the levels of the network, individual company, and specific resource flows. M 3-IS-LCA is tested through an LCA case study that evaluates a potential food waste valorization ISN in Singapore. The case study demonstrated that the methodology can analyze the environmental performance of an entire ISN. Through manipulation of the demand vector in the model, the network-level results can be disaggregated to the levels of individual companies and resource flows. In flow-level analysis, M 3-IS-LCA can isolate the environmental impacts of recycling processes to determine their contribution to the environmental impacts of specific companies or the network. M 3-IS-LCA can be applied to industrial symbiosis collaboration platforms to evaluate the environmental performance of existing or prospective waste-to-resource exchanges.
An Algorithmic Approach to Streamlining Product Carbon Footprint Quantification: A Case Study on Sheet Metal Parts
International Journal of Automation Technology, 2012
Sustainable manufacturing is increasingly being recognized as the direction for technological inn... more Sustainable manufacturing is increasingly being recognized as the direction for technological innovation and implementation in industry. However, to measure and guide technology conceptualization, development, and deployment decisions, a quantifying indicator that is easy to understand is required. The carbon footprint (CFP) is found to be an effective indicator, as its value reflects essential elements of sustainability in manufacturing: materials, energy, and waste treatment. The existing standards provide a general framework to guide CFP quantification but lack explicit formulas for easy adoption. This paper presents an algorithmic approach that aims to granularize the emission source to streamline CFP quantification. This approach pinpoints the direct and indirect contributions and the respective task owners, decentralizes the responsibilities in data collection, and ascertains the degree of control to set realistic targets for CFP reductions. A case study is carried out in a ma...
Industrial symbiosis is a way to realize circular economy in which waste streams from industrial ... more Industrial symbiosis is a way to realize circular economy in which waste streams from industrial production and related activities are collected, reused or recycled into resources. The concept is increasingly incorporated into new company design and industrial park development. There also exist waste management companies who collect and process certain waste streams for economic gains. However, industrialized cities typically experience difficulty to increase their total recycling rate due to the lack of complete and detailed data on the types, quantity, and location of waste streams generated, and hence the economically-viable collection and processing of many waste streams. This paper explores and discusses the feasibility and methods for a big data approach to obtain necessary data for discovery of potential industrial symbioses within the perimeter of a large industrialized city. The aim is to realize the objective of embedding industrial symbioses as an essential part of sustainable urban living and management. .
In today's business environment, the trend towards more product variety and customization is unbr... more In today's business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to analyze a product or one product family on the physical level. Different product families, however, may differ largely in terms of the number and nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. The aim is to cluster these products in new assembly oriented product families for the optimization of existing assembly lines and the creation of future reconfigurable assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach.
One of the major issues companies face in driving environmental sustainability is the lack of foc... more One of the major issues companies face in driving environmental sustainability is the lack of focus. To overcome this issue, we propose a methodology based on the concept of eco-efficiency improvement (EEI) to help companies plan for environmental sustainability improvements. Through this methodology, the current state of a company in terms of environmental performance is assessed and hotspots for improvement are identified. Subsequently, proposed initiatives to address the hotspots are evaluated and prioritised to help the company focus their sustainability efforts to achieve greatest impacts. To demonstrate the application of the methodology, a case study of a fruit juice manufacturing company is presented.
Buildings consume a significant proportion of the world's resources, mostly in the form of materi... more Buildings consume a significant proportion of the world's resources, mostly in the form of materials usage. In addition, with the ongoing efforts focusing on reducing the operational energy consumption of buildings, the embodied emissions of buildings are expected to increase in proportion in the future. With the increasing focus placed on the embodied emissions of buildings, organizations in the construction industry will face requirements to report information regarding the embodied emissions of buildings. However, in order to obtain the embodied emission of buildings, tremendous efforts have to be placed as the process is data intensive. In order to overcome this challenge, a streamlined technique is proposed to minimize the efforts required by practitioner to obtain the embodied carbon footprint. The proposed technique comprises a probabilistic model of emission factor estimators used to estimate the required embodied emissions. Based on the four projects presented as case study for the proposed technique, the practitioner would be required to manually match the appropriate emission factors to the activity data for between 12 and 21% of the data points. This is in contrast to the current traditional technique, which requires the manual matching of 100% of data points. The resultant deviation of the computed embodied carbon footprint from the proposed technique and the current technique was between À0.25% and þ3.65%.
A Cost and Resource Consumption Model for Improving Resource Efficiency of Configurable Roll-to-roll Processing
Procedia CIRP, 2015
ABSTRACT Roll-to-roll (R2R) processing is the process of creating functional films and printed el... more ABSTRACT Roll-to-roll (R2R) processing is the process of creating functional films and printed electronic devices, such as printed RFID and printed lighting, by integrating various large area manufacturing processes into a single manufacturing line. It is poised to be a low-cost and efficient manufacturing technology. However, uncertainty and risk exists for the production of specific products in competition with conventional manufacturing approaches. Therefore, a configurable cost and resource consumption model was developed in order to assess the resource effectiveness of the R2R processing line for a specific product design and to identify areas of improvement. The model considers the technical and parametric relationships in terms of cost, manpower, materials, energy consumption and resource requirements. Using the model, hotspots in the manufacturing line were identified and appropriate recommendations were suggested to minimize resource usage and waste, thereby further reducing the cost of manufacturing and enhancing its commercial viability.
Carbon footprint assessment of a four storey industrial building constructed in Singapore
This paper presents the environmental assessment using carbon footprint as an indicator to quanti... more This paper presents the environmental assessment using carbon footprint as an indicator to quantify the environmental impact generated from "cradle-to-grave" of a four storey industrial building.
A lack of energy management often leads to inefficient use of energy and improper allocation of e... more A lack of energy management often leads to inefficient use of energy and improper allocation of energy resource. To overcome such issues, it is proposed to conduct energy monitoring as a first step towards energy management. Monitoring the energy consumption of a machine creates an understanding of energy usage pattern and may reveal underlying issues that are often neglected by users. A case study of sheet metal part manufacturing reveals inefficient energy consumption from machine that idled 89% during the studied period, as a result of improper scheduling of work order. The study also shows that low power factor of 0.5 may lead to early failure of motor. Results from the examined case signify the importance of energy monitoring in energy management and help to identify opportunities for improving energy efficiency and reducing energy costs
Framework and methods to quantify carbon footprint based on an office environment in Singapore
Journal of Cleaner Production, 2016
Abstract A framework and set of methods to provide quantification of carbon footprint for an offi... more Abstract A framework and set of methods to provide quantification of carbon footprint for an office in Singapore is presented in this work. As office operations become the center of many organization's activities, a rising awareness of climate change puts the focus on the carbon footprint of office operations. Various international standards have provided guidelines in assessing the carbon footprint of organizations. However, a lack of explicit formulation and procedure in these standards makes them difficult to apply. Furthermore, organizations that are just starting to assess their footprint may not have the resources and trained personnel to perform a full-scale assessment. To fill this gap, the framework proposed in this paper categorizes the emission sources from an office into several categories: core devices, shared resources, pantry, and transportation; and a set of quantification methods then guide the practitioner in a visual manner to do their office carbon footprint. A case study was conducted with an organization in Singapore. Results showed that the organization has a monthly office carbon footprint of 2306.57 kg CO 2 e, with major emissions coming from the air-conditioning system and private car usage. The study showed that the method can be used to assess the overall emissions, as well as identifying the major emission sources.
Assessment of industrial sustainability is an important step towards converting the theoretical g... more Assessment of industrial sustainability is an important step towards converting the theoretical goal of sustainable development into practice. One category of sustainability assessment tools is indicators. Indicators are useful tool to summarise and condense complex data into meaningful information and track performance progress over time. This article identifies 40 most commonly used sustainability indicators for Singapore small and medium-sized manufacturing enterprises (SMEs) from four internationally-recognised indicator frameworks through a systematic indicator selection method. These indicators could potentially facilitate local SMEs to manage their manufacturing systems. To ensure appropriate categorisation of the indicators into the sub-categories, content of each sub-category is analysed and a concise definition of nine sustainability terms are put forward. This study has proposed a comprehensive indicator framework in the context of Singapore.
Manufacturing companies are increasingly perceived not only on the basis of their products but al... more Manufacturing companies are increasingly perceived not only on the basis of their products but also of their factories and their embedding within the environment. For this reason, both existing and future factories face the challenges posed by a dynamic and changing market environment. Thus, a gradual change from a throughput to a circular economy leads to the emergence of two categories of factory systems. One category is producing goods, while the second one is recovering and treating waste, residues and the rest of the product at the end of its life. Against this background, this paper introduces the concept of Circulation Factories which combines manufacturing with remanufacturing and recycling into one integrated system. Circulation Factories will enable the realization of an industrial symbiosis transferring waste to value. Drivers and challenges are discussed.
A Big Data Analytics Approach to Develop Industrial Symbioses in Large Cities
Procedia CIRP, 2015
ABSTRACT A big problem for industry and large cities is the increasing waste streams from househo... more ABSTRACT A big problem for industry and large cities is the increasing waste streams from households as well as industries and their impacts to the environment. Treatment of the waste is expensive, and cities face challenges on waste disposal sites. A sustainable solution would be to realize industrial symbioses. The typical approach is to design and develop industrial parks each of which is aimed to be an industrial symbiosis. This approach is proven by successful cases, but is constrained by land scarce cities as well as the limited types and scales of the companies that can be included in an industrial park. The paper proposes a big data analytics approach to realize industrial symbioses among the industries in a city's close proximity. The waste streams and resource requirements of existing companies are identified and matched with resources needs directly or indirectly through conversion processes. The viability, critical elements and technical challenges of the approach are discussed.
The 22nd CIRP conference on Life Cycle Engineering A cost and resource consumption model for improving resource efficiency of configurable roll-to-roll processing
Please refer to published version for the most recent bibliographic citation information. If a pu... more Please refer to published version for the most recent bibliographic citation information. If a published version is known of, the repository item page linked to above, will contain details on accessing it.
UM3-LCE3-ISN: a methodology for multi-level life cycle environmental and economic evaluation of industrial symbiosis networks
The International Journal of Life Cycle Assessment, 2022
Life cycle assessment (LCA) and life cycle costing (LCC) are state-of-the-art methods used to hol... more Life cycle assessment (LCA) and life cycle costing (LCC) are state-of-the-art methods used to holistically measure the environmental and economic performance of industrial symbiosis networks (ISNs). Existing methodologies face a challenge in unifying LCA and LCC of an ISN in a single model that can disaggregate the network-level results to the entity and resource flow levels. This study introduces UM3-LCE3-ISN, a methodology for multi-level matrix-based modeling for life cycle environmental and economic evaluation of ISNs. The UM3-LCE3-ISN methodology is designed to conduct a process-based LCA and LCC of any ISN scenario. The methodology constructs a single matrix-based model that represents the physical and monetary flows of an ISN across the entire life cycle. The demand and price vectors in the model can be manipulated to produce LCA and LCC results of an ISN at the levels of the entire network, individual companies, and specific resource flows. A formalism is provided that outlines the steps for model construction and multi-level analysis. Verification of the model constructed can be done by producing scaled technology and monetary matrices of an ISN. UM3-LCE3-ISN is tested through a case study of an urban agri-food ISN comprising five entities engaged in open and closed-loop recycling. The case study results demonstrated that UM3-LCE3-ISN can be used to compute the life cycle environmental impacts and net present value of ISNs at the three different stakeholder levels. Only one matrix model was required for each scenario to compute the LCA and LCC results for multiple stakeholders through one computation as opposed to several computations in multiple separate models. UM3-LCE3-ISN can produce granular LCA and LCC results regarding specific waste-to-resource conversion processes within an ISN and their contribution to the environmental and economic performance of specific entities. Overall, UM3-LCE3-ISN is able to unify potential conflicting assumptions and data used by different models and obtain more holistic LCA and LCC results that are harmonized for stakeholders across different levels. The UM3-LCE3-ISN methodology can be applied in industrial symbiosis facilitation tools that allow diverse stakeholders such as policy-makers, urban planners, businesses, and product designers to operate on a common platform to determine the life cycle environmental and economic performance of an ISN from multiple perspectives of interest. This would allow diverse stakeholders to make holistic evidence-based decisions and strategies for developing ISNs in different sectors that enable a large-scale transition to a circular economy.
The indoor laboratory-scale microalgae culture was elevated to 50 liter in outdoor photobioreacto... more The indoor laboratory-scale microalgae culture was elevated to 50 liter in outdoor photobioreactors for the cultivation of an oil-rich microalga, Chlorella vulgaris ESP-31. Under phototrophic and photoheterotrophic conditions using CO2 and acetic acid as carbon source, respectively , the lipid productivity and lipid content obtained were 30-31 mg/L/d and 35-44%, respectively. The effect of inoculum sizes on the performance of biomass and lipid production under phototrophic cultivation was also investigated. The lipid productivity of C. vulgaris ESP-31 was further improved to 47.6 mg/L/d when a higher inoculum size of 0.70 g/L was used. Finally, to avoid severe contamination problem during outdoor cultivation in the summer time, a two-stage lipid accumulation strategy was employed. The results show that the proposed two-stage process was able to avoid the bacterial contamination and enhanced the lipid content and lipid productivity of Chlorella vulgaris ESP-31.
Life cycle assessment of single-use surgical and embedded filtration layer (EFL) reusable face mask
Resources, Conservation and Recycling, 2021
Background The outbreak of the COVID-19 pandemic has led to an unprecedented amount of face mask ... more Background The outbreak of the COVID-19 pandemic has led to an unprecedented amount of face mask consumption around the world. The increase in face mask consumption has brought focus to their environmental impact. To keep up with the increased demand for face masks, different variations of reusable face masks such as the embedded filtration layer (EFL) reusable face mask have emerged in the market. This study quantifies the environmental impact of the EFL reusable face mask and the single-use surgical face mask. Methods The life cycle assessment (LCA) study of the entire value chain from cradle-to-grave is applied to each face mask. Both face masks are evaluated over 1 functional unit (FU) of 31 12-h days for a single person. The ReCiPe method with the Hierachist perspective was applied. A total of nine impact categories as well as the generated waste of each face mask are evaluated. Results The results show that for 1 functional unit, the use of single-use surgical face mask and EFL reusable face mask will contribute 0.580 kg CO2-eq and 0.338 kg CO2-eq to climate change and generate 0.004 kg and 0.0004 kg of waste respectively. Conclusion Comparing both face masks, the EFL reusable face mask will have a lower emission of at least 30% in terms of the generated waste and the impact categories considered, except for water depletion, freshwater eutrophication, marine eutrophication, and human toxicity.
In industrial symbiosis networks (ISNs), there are multiple stakeholders involved that require di... more In industrial symbiosis networks (ISNs), there are multiple stakeholders involved that require different levels of environmental performance insight for specific organizational goals. Life cycle assessment (LCA) has been widely applied to holistically evaluate the environmental benefits of ISNs and identify burden shifts. Representing ISNs in LCAs is complex due to resource flows with multiple sources and sinks and inter-company waste-to-resource exchanges. Furthermore, existing LCA methodologies face challenges in using one model for multi-level analysis to provide the network, entity, and resource flow-level perspectives of LCA results. To address these challenges, this study introduces M 3-IS-LCA, a methodology for multi-level matrix-based modeling and analysis of the life cycle environmental impacts of ISNs. A formalism is outlined for constructing the model and analyzing the model so that LCA results can be provided at the levels of the network, individual company, and specific resource flows. M 3-IS-LCA is tested through an LCA case study that evaluates a potential food waste valorization ISN in Singapore. The case study demonstrated that the methodology can analyze the environmental performance of an entire ISN. Through manipulation of the demand vector in the model, the network-level results can be disaggregated to the levels of individual companies and resource flows. In flow-level analysis, M 3-IS-LCA can isolate the environmental impacts of recycling processes to determine their contribution to the environmental impacts of specific companies or the network. M 3-IS-LCA can be applied to industrial symbiosis collaboration platforms to evaluate the environmental performance of existing or prospective waste-to-resource exchanges.
An Algorithmic Approach to Streamlining Product Carbon Footprint Quantification: A Case Study on Sheet Metal Parts
International Journal of Automation Technology, 2012
Sustainable manufacturing is increasingly being recognized as the direction for technological inn... more Sustainable manufacturing is increasingly being recognized as the direction for technological innovation and implementation in industry. However, to measure and guide technology conceptualization, development, and deployment decisions, a quantifying indicator that is easy to understand is required. The carbon footprint (CFP) is found to be an effective indicator, as its value reflects essential elements of sustainability in manufacturing: materials, energy, and waste treatment. The existing standards provide a general framework to guide CFP quantification but lack explicit formulas for easy adoption. This paper presents an algorithmic approach that aims to granularize the emission source to streamline CFP quantification. This approach pinpoints the direct and indirect contributions and the respective task owners, decentralizes the responsibilities in data collection, and ascertains the degree of control to set realistic targets for CFP reductions. A case study is carried out in a ma...
Industrial symbiosis is a way to realize circular economy in which waste streams from industrial ... more Industrial symbiosis is a way to realize circular economy in which waste streams from industrial production and related activities are collected, reused or recycled into resources. The concept is increasingly incorporated into new company design and industrial park development. There also exist waste management companies who collect and process certain waste streams for economic gains. However, industrialized cities typically experience difficulty to increase their total recycling rate due to the lack of complete and detailed data on the types, quantity, and location of waste streams generated, and hence the economically-viable collection and processing of many waste streams. This paper explores and discusses the feasibility and methods for a big data approach to obtain necessary data for discovery of potential industrial symbioses within the perimeter of a large industrialized city. The aim is to realize the objective of embedding industrial symbioses as an essential part of sustainable urban living and management. .
In today's business environment, the trend towards more product variety and customization is unbr... more In today's business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to analyze a product or one product family on the physical level. Different product families, however, may differ largely in terms of the number and nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. The aim is to cluster these products in new assembly oriented product families for the optimization of existing assembly lines and the creation of future reconfigurable assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach.
One of the major issues companies face in driving environmental sustainability is the lack of foc... more One of the major issues companies face in driving environmental sustainability is the lack of focus. To overcome this issue, we propose a methodology based on the concept of eco-efficiency improvement (EEI) to help companies plan for environmental sustainability improvements. Through this methodology, the current state of a company in terms of environmental performance is assessed and hotspots for improvement are identified. Subsequently, proposed initiatives to address the hotspots are evaluated and prioritised to help the company focus their sustainability efforts to achieve greatest impacts. To demonstrate the application of the methodology, a case study of a fruit juice manufacturing company is presented.
Buildings consume a significant proportion of the world's resources, mostly in the form of materi... more Buildings consume a significant proportion of the world's resources, mostly in the form of materials usage. In addition, with the ongoing efforts focusing on reducing the operational energy consumption of buildings, the embodied emissions of buildings are expected to increase in proportion in the future. With the increasing focus placed on the embodied emissions of buildings, organizations in the construction industry will face requirements to report information regarding the embodied emissions of buildings. However, in order to obtain the embodied emission of buildings, tremendous efforts have to be placed as the process is data intensive. In order to overcome this challenge, a streamlined technique is proposed to minimize the efforts required by practitioner to obtain the embodied carbon footprint. The proposed technique comprises a probabilistic model of emission factor estimators used to estimate the required embodied emissions. Based on the four projects presented as case study for the proposed technique, the practitioner would be required to manually match the appropriate emission factors to the activity data for between 12 and 21% of the data points. This is in contrast to the current traditional technique, which requires the manual matching of 100% of data points. The resultant deviation of the computed embodied carbon footprint from the proposed technique and the current technique was between À0.25% and þ3.65%.
A Cost and Resource Consumption Model for Improving Resource Efficiency of Configurable Roll-to-roll Processing
Procedia CIRP, 2015
ABSTRACT Roll-to-roll (R2R) processing is the process of creating functional films and printed el... more ABSTRACT Roll-to-roll (R2R) processing is the process of creating functional films and printed electronic devices, such as printed RFID and printed lighting, by integrating various large area manufacturing processes into a single manufacturing line. It is poised to be a low-cost and efficient manufacturing technology. However, uncertainty and risk exists for the production of specific products in competition with conventional manufacturing approaches. Therefore, a configurable cost and resource consumption model was developed in order to assess the resource effectiveness of the R2R processing line for a specific product design and to identify areas of improvement. The model considers the technical and parametric relationships in terms of cost, manpower, materials, energy consumption and resource requirements. Using the model, hotspots in the manufacturing line were identified and appropriate recommendations were suggested to minimize resource usage and waste, thereby further reducing the cost of manufacturing and enhancing its commercial viability.
Carbon footprint assessment of a four storey industrial building constructed in Singapore
This paper presents the environmental assessment using carbon footprint as an indicator to quanti... more This paper presents the environmental assessment using carbon footprint as an indicator to quantify the environmental impact generated from "cradle-to-grave" of a four storey industrial building.
A lack of energy management often leads to inefficient use of energy and improper allocation of e... more A lack of energy management often leads to inefficient use of energy and improper allocation of energy resource. To overcome such issues, it is proposed to conduct energy monitoring as a first step towards energy management. Monitoring the energy consumption of a machine creates an understanding of energy usage pattern and may reveal underlying issues that are often neglected by users. A case study of sheet metal part manufacturing reveals inefficient energy consumption from machine that idled 89% during the studied period, as a result of improper scheduling of work order. The study also shows that low power factor of 0.5 may lead to early failure of motor. Results from the examined case signify the importance of energy monitoring in energy management and help to identify opportunities for improving energy efficiency and reducing energy costs
Framework and methods to quantify carbon footprint based on an office environment in Singapore
Journal of Cleaner Production, 2016
Abstract A framework and set of methods to provide quantification of carbon footprint for an offi... more Abstract A framework and set of methods to provide quantification of carbon footprint for an office in Singapore is presented in this work. As office operations become the center of many organization's activities, a rising awareness of climate change puts the focus on the carbon footprint of office operations. Various international standards have provided guidelines in assessing the carbon footprint of organizations. However, a lack of explicit formulation and procedure in these standards makes them difficult to apply. Furthermore, organizations that are just starting to assess their footprint may not have the resources and trained personnel to perform a full-scale assessment. To fill this gap, the framework proposed in this paper categorizes the emission sources from an office into several categories: core devices, shared resources, pantry, and transportation; and a set of quantification methods then guide the practitioner in a visual manner to do their office carbon footprint. A case study was conducted with an organization in Singapore. Results showed that the organization has a monthly office carbon footprint of 2306.57 kg CO 2 e, with major emissions coming from the air-conditioning system and private car usage. The study showed that the method can be used to assess the overall emissions, as well as identifying the major emission sources.
Assessment of industrial sustainability is an important step towards converting the theoretical g... more Assessment of industrial sustainability is an important step towards converting the theoretical goal of sustainable development into practice. One category of sustainability assessment tools is indicators. Indicators are useful tool to summarise and condense complex data into meaningful information and track performance progress over time. This article identifies 40 most commonly used sustainability indicators for Singapore small and medium-sized manufacturing enterprises (SMEs) from four internationally-recognised indicator frameworks through a systematic indicator selection method. These indicators could potentially facilitate local SMEs to manage their manufacturing systems. To ensure appropriate categorisation of the indicators into the sub-categories, content of each sub-category is analysed and a concise definition of nine sustainability terms are put forward. This study has proposed a comprehensive indicator framework in the context of Singapore.
Manufacturing companies are increasingly perceived not only on the basis of their products but al... more Manufacturing companies are increasingly perceived not only on the basis of their products but also of their factories and their embedding within the environment. For this reason, both existing and future factories face the challenges posed by a dynamic and changing market environment. Thus, a gradual change from a throughput to a circular economy leads to the emergence of two categories of factory systems. One category is producing goods, while the second one is recovering and treating waste, residues and the rest of the product at the end of its life. Against this background, this paper introduces the concept of Circulation Factories which combines manufacturing with remanufacturing and recycling into one integrated system. Circulation Factories will enable the realization of an industrial symbiosis transferring waste to value. Drivers and challenges are discussed.
A Big Data Analytics Approach to Develop Industrial Symbioses in Large Cities
Procedia CIRP, 2015
ABSTRACT A big problem for industry and large cities is the increasing waste streams from househo... more ABSTRACT A big problem for industry and large cities is the increasing waste streams from households as well as industries and their impacts to the environment. Treatment of the waste is expensive, and cities face challenges on waste disposal sites. A sustainable solution would be to realize industrial symbioses. The typical approach is to design and develop industrial parks each of which is aimed to be an industrial symbiosis. This approach is proven by successful cases, but is constrained by land scarce cities as well as the limited types and scales of the companies that can be included in an industrial park. The paper proposes a big data analytics approach to realize industrial symbioses among the industries in a city's close proximity. The waste streams and resource requirements of existing companies are identified and matched with resources needs directly or indirectly through conversion processes. The viability, critical elements and technical challenges of the approach are discussed.
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