The Experts below are selected from a list of 86394 Experts worldwide ranked by ideXlab platform
Bernd Nowack - One of the best experts on this subject based on the ideXlab platform.
-
dynamic probabilistic Material Flow Analysis of rubber release from tires into the environment
Environmental Pollution, 2020Co-Authors: Ramona Sieber, Delphine Kawecki, Bernd NowackAbstract:The presence of microplastics in the environment is currently receiving a lot of attention. Rubber particles from tire wear have been estimated in several mass emission inventories to be a major contributor to the total microplastic release. This work used dynamic probabilistic Material Flow Analysis to quantify the Flows of rubber particles from tires to roads and further onto soils and surface waters of Switzerland. The model considered the whole life-cycle of tires from import over the use phase to the end-of-life and the re-use of scrap tires. Uncertainties of model parameters and data variability were considered by using a probabilistic approach. Mass Flows onto soils and through road drainage by both uncontrolled dispersal and engineered systems are considered. In addition, the release of rubber from artificial turfs was included. The accumulation of rubber particles in the environment was quantified over the time frame from 1988 to 2018. The results show that in 2018, 1.29 ± 0.45 kg/capita of rubber was emitted from tire wear (97%) and rubber granules (3%). Street cleaning and waste water treatment removed around 26% of this rubber mass before finally reaching the receiving environmental compartment, resulting in an effective input of 0.96 ± 0.35 kg/capita of rubber in 2018 into the natural environment. Most of this mass (74%) was deposited on roadside soils (up to 5 m distance from road), 22% Flowed into surface waters and the remaining part (4%) was emitted to soils. The dynamic modeling showed an increase of the input into the environment by about 10% from 1990 to 2018. The ban of sewage sludge application on soils resulted in a marked decrease in the amount transferred to soils after the year 2000. In total, 219 ± 22 ktonnes of rubber particles have accumulated in the environment since 1988 in Switzerland.
-
considering the forms of released engineered nanoMaterials in probabilistic Material Flow Analysis
Environmental Pollution, 2018Co-Authors: Veronique Adam, Alejandro Caballeroguzman, Bernd NowackAbstract:Abstract Most existing models for assessing the releases of engineered nanoMaterials (ENMs) into the environment are based on the assumption that ENMs remain in their pristine forms during their whole life cycle. It is known, however, that this is not always the case as ENMs are often embedded into solid matrices during manufacturing and can undergo physical or chemical transformations during their life cycle, e.g. upon release to wastewater. In this work, we present a method for systematically assessing the forms in which nano-Ag and nano-TiO2 Flow through their life cycle (i.e. production, manufacturing, use and disposal) to their points of release to air, soil and surface water. Input data on the forms of released ENMs were probability distributions based on peer-reviewed literature. Release data were incorporated into a probabilistic Material Flow Analysis model to quantify the proportions of ENMs in product-embedded, matrix-embedded, pristine, transformed and dissolved forms in all technical and environmental compartments into which they Flow, at the European scale. Releases of nano-Ag to surface water and soil were modelled to occur primarily in transformed forms (Q25 and Q75 of 34–58% and 78–86%, respectively, with means of 53% and 82%), while releases to air were mostly in pristine and matrix-embedded forms (38–46% and 36–44%, respectively, with means of 42% and 40%). In contrast, nano-TiO2 releases to air, soil and water were estimated to be predominantly in pristine form (75–85%, 90–95%, 96–98%, respectively, with means of 80%, 91% and 97%). The distributions of ENM releases between forms developed here will improve the representativeness and appropriateness of input data for environmental fate modelling and risk assessment of ENMs.
-
probabilistic Material Flow Analysis of seven commodity plastics in europe
Environmental Science & Technology, 2018Co-Authors: Delphine Kawecki, Paul R W Scheeder, Bernd NowackAbstract:The omnipresence of plastics in our lives and their ever-increasing application range continuously raise the requirements for the monitoring of environmental and health impacts related to both plastics and their additives. We present a static probabilistic Material Flow Analysis of seven polymers through the European and Swiss anthropospheres to provide a strong basis for exposure assessments of polymer-related impacts, which necessitates that the plastic Flows from production to use and finally to waste management are well-understood. We consider seven different polymers, chosen for their popularity and application variety: low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), expanded polystyrene (EPS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). We include synthetic textile products and consider trade Flows at various stages of the life cycle, thus achieving a complete overview of the consumption for these polymers. In Europe, the order of consumption is PP > LDPE > PET > HDPE > PVC > PS > EPS. Textile products account for 42 ± 3% of the consumption of PET and 22 ± 4% of PP. Incineration is the major waste management method for HDPE, PS, and EPS. No significant difference between landfilling and incineration for the remaining polymers is found. The highest recycling share is found for PVC. These results can serve as a basis for a detailed assessment of exposure pathways of plastics or their additives in the environment or exposure of additives on human health.
-
possibilities and limitations of modeling environmental exposure to engineered nanoMaterials by probabilistic Material Flow Analysis
Environmental Toxicology and Chemistry, 2010Co-Authors: Fadri Gottschalk, Tobias Sonderer, Roland W Scholz, Bernd NowackAbstract:Information on environmental concentrations is needed to assess the risks that engineered nanoMaterials (ENM) may pose to the environment. In this study, predicted environmental concentrations (PEC) were modeled for nano-TiO2, carbon nanotubes (CNT) and nano-Ag for Switzerland. Based on a life-cycle perspective, the model considered as input parameters the production volumes of the ENMs, the manufacturing and consumption quantities of products containing those Materials, and the fate and pathways of ENMs in natural and technical environments. Faced with a distinct scarcity of data, we used a probabilistic Material Flow Analysis model, treating all parameters as probability distributions. The modeling included Monte Carlo and Markov Chain Monte Carlo simulations as well as a sensitivity and uncertainty Analysis. The PEC values of the ENMs in the different environmental compartments vary widely due to different ENM production volumes and different life cycles of the nanoproducts. The use of ENM in products with high water relevance leads to higher water and sediment concentrations for nano-TiO2 and nano-Ag, compared to CNTs, where smaller amounts of ENM reach the aquatic compartments. This study also presents a sensitivity Analysis and a comprehensive discussion of the uncertainties of the simulation results and the limitations of the used approach. To estimate potential risks, the PEC values were compared to the predicted-no-effect concentrations (PNEC) derived from published data. The risk quotients (PEC/PNEC) for nano-TiO2 and nano-Ag were larger than one for treated wastewater and much smaller for all other environmental compartments (e.g., water, sediments, soils). We conclude that probabilistic modeling is very useful for predicting environmental concentrations of ENMs given the current lack of substantiated data.
-
possibilities and limitations of modeling environmental exposure to engineered nanoMaterials by probabilistic Material Flow Analysis
Environmental Toxicology and Chemistry, 2010Co-Authors: Tobias Sonderer, Fadri Gottschalk, Roland W Scholz, Bernd NowackAbstract:Information on environmental concentrations is needed to assess the risks that engineered nanoMaterials (ENM) may pose to the environment. In this study, predicted environmental concentrations (PEC) were modeled for nano-TiO2, carbon nanotubes (CNT) and nano-Ag for Switzerland. Based on a life-cycle perspective, the model considered as input parameters the production volumes of the ENMs, the manufacturing and consumption quantities of products containing those Materials, and the fate and pathways of ENMs in natural and technical environments. Faced with a distinct scarcity of data, we used a probabilistic Material Flow Analysis model, treating all parameters as probability distributions. The modeling included Monte Carlo and Markov Chain Monte Carlo simulations as well as a sensitivity and uncertainty Analysis. The PEC values of the ENMs in the different environmental compartments vary widely due to different ENM production volumes and different life cycles of the nanoproducts. The use of ENM in products with high water relevance leads to higher water and sediment concentrations for nano-TiO2 and nano-Ag, compared to CNTs, where smaller amounts of ENM reach the aquatic compartments. This study also presents a sensitivity Analysis and a comprehensive discussion of the uncertainties of the simulation results and the limitations of the used approach. To estimate potential risks, the PEC values were compared to the predicted-no-effect concentrations (PNEC) derived from published data. The risk quotients (PEC/PNEC) for nano-TiO2 and nano-Ag were larger than one for treated wastewater and much smaller for all other environmental compartments (e.g., water, sediments, soils). We conclude that probabilistic modeling is very useful for predicting environmental concentrations of ENMs given the current lack of substantiated data. Environ. Toxicol. Chem. 2010;29:1036–1048. © 2010 SETAC
Paul H. Brunner - One of the best experts on this subject based on the ideXlab platform.
-
Material Flow Analysis as a tool to improve waste management systems the case of austria
Environmental Science & Technology, 2017Co-Authors: Astrid Allesch, Paul H. BrunnerAbstract:This paper demonstrates the power of Material Flow Analysis (MFA) for designing waste management (WM) systems and for supporting decisions with regards to given environmental and resource goals. Based on a comprehensive case study of a nationwide WM-system, advantages and drawbacks of a mass balance approach are discussed. Using the software STAN, a Material Flow system comprising all relevant inputs, stocks and outputs of wastes, products, residues, and emissions is established and quantified. Material balances on the level of goods and selected substances (C, Cd, Cr, Cu, Fe, Hg, N, Ni, P, Pb, Zn) are developed to characterize this WM-system. The MFA results serve well as a base for further assessments. Based on given goals, stakeholders engaged in this study selected the following seven criteria for evaluating their WM-system: (i) waste input into the system, (ii) export of waste (iii) gaseous emissions from waste treatment plants, (iv) long-term gaseous and liquid emissions from landfills, (v) waste be...
-
handbook of Material Flow Analysis for environmental resource and waste engineers second edition
2016Co-Authors: Paul H. Brunner, Helmut RechbergerAbstract:In this second edition of a bestseller, authors Paul H. Brunner and Helmut Rechberger guide professional newcomers as well as experienced engineers and scientists towards mastering the art of Material Flow Analysis (MFA) from the very beginning to an advanced state of Material balances of complex systems. Handbook of Material Flow Analysis: For Environmental, Resource, and Waste Engineers, Second Edition serves as a concise and reproducible methodology as well as a basis for Analysis, assessment and improvement of anthropogenic systems through an approach that is helpfully uniform and standardized. The methodology featured in this book is a vital resource for generating new data, fostering understanding, and increasing knowledge to benefit the growing MFA community working in the fields of industrial ecology, resource management, waste management, and environmental protection. This new second edition takes into account all new developments and readers will profit from a new exploration of STAN software, newly added citations, and thoroughly described case studies that reveal the potential of MFA to solve industrial ecology challenges.
-
Material Flow Analysis as a decision support tool for waste management a literature review
Journal of Industrial Ecology, 2015Co-Authors: Astrid Allesch, Paul H. BrunnerAbstract:This article reviews, categorizes, and evaluates the objectives, means, and results of the application of Material Flow Analysis (MFA) in waste management. It identifies those areas where MFA methodologies are most successful in supporting waste management decisions. The focus of this review is on the distinction between MFA on the level of goods and on the level of substances. Based on 83 reviewed studies, potentials, strengths, and weaknesses are investigated for the two levels of MFA when applied for Analysis, evaluation, and improvement of waste management systems. The differences are discussed in view of effectiveness, applicability, and data availability. The results show that MFA on the level of goods are instrumental for understanding how waste management systems function, facilitating the connections of stakeholders, authorities, and waste management companies. The substance level is essential to assess qualitative aspects regarding resources and environment. Knowledge about the transformation, transport, and storage of valuable and hazardous substances forms the base for identifying both resource potentials and risks for human health and the environment. The results of this review encourage the application of MFA on both levels of goods and substances for decision making in waste management. Because of the mass balance principle, this combination has proven to be a powerful tool for comprehensively assessing if a chosen system reaches designated waste management goals.
-
combination of Material Flow Analysis and substance Flow Analysis a powerful approach for decision support in waste management
Waste Management & Research, 2014Co-Authors: Nemanja Stanisavljevic, Paul H. BrunnerAbstract:The novelty of this paper is the demonstration of the effectiveness of combining Material Flow Analysis (MFA) with substance Flow Analysis (SFA) for decision making in waste management. Both MFA and SFA are based on the mass balance principle. While MFA alone has been applied often for analysing Material Flows quantitatively and hence to determine the capacities of waste treatment processes, SFA is more demanding but instrumental in evaluating the performance of a waste management system regarding the goals "resource conservation" and "environmental protection". SFA focuses on the transformations of wastes during waste treatment: valuable as well as hazardous substances and their transformations are followed through the entire waste management system. A substance-based approach is required because the economic and environmental properties of the products of waste management - recycling goods, residues and emissions - are primarily determined by the content of specific precious or harmful substances. To support the case that MFA and SFA should be combined, a case study of waste management scenarios is presented. For three scenarios, total Material Flows are quantified by MFA, and the mass Flows of six indicator substances (C, N, Cl, Cd, Pb, Hg) are determined by SFA. The combined results are compared to the status quo in view of fulfilling the goals of waste management. They clearly point out specific differences between the chosen scenarios, demonstrating potentials for improvement and the value of the combination of MFA/SFA for decision making in waste management.
-
combination of Material Flow Analysis and substance Flow Analysis a powerful approach for decision support in waste management
Waste Management & Research, 2014Co-Authors: Nemanja Stanisavljevic, Paul H. BrunnerAbstract:The novelty of this paper is the demonstration of the effectiveness of combining Material Flow Analysis (MFA) with substance Flow Analysis (SFA) for decision making in waste management. Both MFA and SFA are based on the mass balance principle. While MFA alone has been applied often for analysing Material Flows quantitatively and hence to determine the capacities of waste treatment processes, SFA is more demanding but instrumental in evaluating the performance of a waste management system regarding the goals “resource conservation” and “environmental protection”. SFA focuses on the transformations of wastes during waste treatment: valuable as well as hazardous substances and their transformations are followed through the entire waste management system. A substance-based approach is required because the economic and environmental properties of the products of waste management – recycling goods, residues and emissions – are primarily determined by the content of specific precious or harmful substances. To su...
Tetsuya Nagasaka - One of the best experts on this subject based on the ideXlab platform.
-
Identifying the Substance Flow of Metals Embedded in Japanese International Trade by Use of Waste Input-Output Material Flow Analysis (WIO-MFA) Model
Isij International, 2011Co-Authors: Kenichi Nakajima, Kazuyo Matsubae, Yasushi Kondo, Shinichiro Nakamura, Keisuke Nansai, Shigemi Kagawa, Rokuta Inaba, Tetsuya NagasakaAbstract:This study proposes a method of combining a waste input–output Material Flow Analysis (WIO-MFA) model with trade statistical data to identify the Flows of substances embedded in trade commodities. We focused on the case of Japan as a typical processing and trading country, and we estimated each mass of iron and aluminum embedded in the imports and exports of 300 product items categorized in the WIO-MFA. We found that iron ore imported from Australia, Brazil, and India as a raw Material is processed and exported to South Korea, China, and other Asian countries as steel Materials and to the United States as steel Materials and automobiles. Primary aluminum imported from Russia, Australia, and Brazil as a raw Material is processed and exported to Asia as rolled Materials and to the United States as rolled Materials and automobiles.
-
analyzing polyvinyl chloride in japan with the waste input output Material Flow Analysis model
Journal of Industrial Ecology, 2009Co-Authors: Shinichiro Nakamura, Kenichi Nakajima, Yoshie Yoshizawa, Kazuyo Matsubaeyokoyama, Tetsuya NagasakaAbstract:Summary Effective life cycle management of polyvinyl chloride (PVC) calls for the separation of end-of-life PVC products at the time of collection not only from other wastes but among different PVC types as well. Information about the Flow of PVC products in the economy is important for this purpose. Within the framework of the Japanese input−output (IO) table for the year 2000, with around 400 industry sectors, the Flow of PVC is captured in terms of six PVC-embodying products and in terms of three PVC types, (1) flexible PVC (soft PVC), (2) rigid PVC (hard PVC), and (3) others. The degree of resolution; the consideration of different PVC types, which are seldom performed in the Material Flow Analysis (MFA) literature; and the use of waste input−output Material Flow Analysis (WIO-MFA) represent distinguishing features of our study. The use of WIO-MFA methodology enables one to convert a monetary input−output table into a physical interindustry Flow table involving an arbitrary number of Materials under full consideration of the mass balance. The results indicate that 40% of the PVC produced in Japan is exported (as resins and as products such as passenger motor cars), and the rest is accumulated mostly as capital stock. The largest share of accumulation goes to public construction in the form of plates, pipes, and bars, which are mostly hard-PVC products.
Shinichiro Nakamura - One of the best experts on this subject based on the ideXlab platform.
-
Identifying the Substance Flow of Metals Embedded in Japanese International Trade by Use of Waste Input-Output Material Flow Analysis (WIO-MFA) Model
Isij International, 2011Co-Authors: Kenichi Nakajima, Kazuyo Matsubae, Yasushi Kondo, Shinichiro Nakamura, Keisuke Nansai, Shigemi Kagawa, Rokuta Inaba, Tetsuya NagasakaAbstract:This study proposes a method of combining a waste input–output Material Flow Analysis (WIO-MFA) model with trade statistical data to identify the Flows of substances embedded in trade commodities. We focused on the case of Japan as a typical processing and trading country, and we estimated each mass of iron and aluminum embedded in the imports and exports of 300 product items categorized in the WIO-MFA. We found that iron ore imported from Australia, Brazil, and India as a raw Material is processed and exported to South Korea, China, and other Asian countries as steel Materials and to the United States as steel Materials and automobiles. Primary aluminum imported from Russia, Australia, and Brazil as a raw Material is processed and exported to Asia as rolled Materials and to the United States as rolled Materials and automobiles.
-
analyzing polyvinyl chloride in japan with the waste input output Material Flow Analysis model
Journal of Industrial Ecology, 2009Co-Authors: Shinichiro Nakamura, Kenichi Nakajima, Yoshie Yoshizawa, Kazuyo Matsubaeyokoyama, Tetsuya NagasakaAbstract:Summary Effective life cycle management of polyvinyl chloride (PVC) calls for the separation of end-of-life PVC products at the time of collection not only from other wastes but among different PVC types as well. Information about the Flow of PVC products in the economy is important for this purpose. Within the framework of the Japanese input−output (IO) table for the year 2000, with around 400 industry sectors, the Flow of PVC is captured in terms of six PVC-embodying products and in terms of three PVC types, (1) flexible PVC (soft PVC), (2) rigid PVC (hard PVC), and (3) others. The degree of resolution; the consideration of different PVC types, which are seldom performed in the Material Flow Analysis (MFA) literature; and the use of waste input−output Material Flow Analysis (WIO-MFA) represent distinguishing features of our study. The use of WIO-MFA methodology enables one to convert a monetary input−output table into a physical interindustry Flow table involving an arbitrary number of Materials under full consideration of the mass balance. The results indicate that 40% of the PVC produced in Japan is exported (as resins and as products such as passenger motor cars), and the rest is accumulated mostly as capital stock. The largest share of accumulation goes to public construction in the form of plates, pipes, and bars, which are mostly hard-PVC products.
-
waste input output Material Flow Analysis and its application to quantity metals
Journal of The Japan Institute of Metals, 2006Co-Authors: Shinichiro Nakamura, Kenichi NakajimaAbstract:This paper develops a theoretical model of Material Flow Analysis (MFA) within the framework of the Waste Input-Output model (WIO) (Nakamura and Kondo). The model is developed based on two fundamental ingredients: yield ratios and the degree of fabrication. In manufacturing process, multiplication of physical inputs by the yield ratios gives the portion that enters physical outputs, with the rest being discarded as process waste without entering outputs. In input-output Analysis, the degree of fabrication can be visualized as triangularity of the input coefficients matrix (goods of lower degree of fabrication can enter those of higher fabrication, but the reverse does not hold), which is known to emerge through an appropriate reordering of sectors. Application to the Japanese IO data indicates that the model can provide accurate estimates of the weight as well as the composition of metals (Fe, Cu, Pb, Zn, and Al) used in a passenger car. The model is also used to estimate the major final use categories (household consumption, public consumption, capital investment, inventory investment, and export) of metals.
-
waste input output Material Flow Analysis of metals in the japanese economy
Materials Transactions, 2005Co-Authors: Shinichiro Nakamura, Kenichi NakajimaAbstract:This paper develops a theoretical model of Material Flow Analysis (MFA) within the framework of the Waste Input–Output model (WIO) (Nakamura and Kondo). The model is developed based on two fundamental ingredients: yield ratios and the degree of fabrication. In manufacturing process, multiplication of physical inputs by the yield ratios gives the portion that enters physical outputs, with the rest being discarded as process waste without entering outputs. In input–output Analysis, the degree of fabrication can be visualized as triangularity of the input coefficients matrix (goods of lower degree of fabrication can enter those of higher fabrication, but the reverse does not hold), which is known to emerge through an appropriate reordering of sectors. Application to the Japanese IO data indicates that the model can provide accurate estimates of the weight as well as the composition of metals (Fe, Cu, Pb, Zn, and Al) used in a passenger car. The model is also used to estimate the major final use categories (household consumption, public consumption, capital investment, inventory investment, and export) of metals.
Kenichi Nakajima - One of the best experts on this subject based on the ideXlab platform.
-
Identifying the Substance Flow of Metals Embedded in Japanese International Trade by Use of Waste Input-Output Material Flow Analysis (WIO-MFA) Model
Isij International, 2011Co-Authors: Kenichi Nakajima, Kazuyo Matsubae, Yasushi Kondo, Shinichiro Nakamura, Keisuke Nansai, Shigemi Kagawa, Rokuta Inaba, Tetsuya NagasakaAbstract:This study proposes a method of combining a waste input–output Material Flow Analysis (WIO-MFA) model with trade statistical data to identify the Flows of substances embedded in trade commodities. We focused on the case of Japan as a typical processing and trading country, and we estimated each mass of iron and aluminum embedded in the imports and exports of 300 product items categorized in the WIO-MFA. We found that iron ore imported from Australia, Brazil, and India as a raw Material is processed and exported to South Korea, China, and other Asian countries as steel Materials and to the United States as steel Materials and automobiles. Primary aluminum imported from Russia, Australia, and Brazil as a raw Material is processed and exported to Asia as rolled Materials and to the United States as rolled Materials and automobiles.
-
analyzing polyvinyl chloride in japan with the waste input output Material Flow Analysis model
Journal of Industrial Ecology, 2009Co-Authors: Shinichiro Nakamura, Kenichi Nakajima, Yoshie Yoshizawa, Kazuyo Matsubaeyokoyama, Tetsuya NagasakaAbstract:Summary Effective life cycle management of polyvinyl chloride (PVC) calls for the separation of end-of-life PVC products at the time of collection not only from other wastes but among different PVC types as well. Information about the Flow of PVC products in the economy is important for this purpose. Within the framework of the Japanese input−output (IO) table for the year 2000, with around 400 industry sectors, the Flow of PVC is captured in terms of six PVC-embodying products and in terms of three PVC types, (1) flexible PVC (soft PVC), (2) rigid PVC (hard PVC), and (3) others. The degree of resolution; the consideration of different PVC types, which are seldom performed in the Material Flow Analysis (MFA) literature; and the use of waste input−output Material Flow Analysis (WIO-MFA) represent distinguishing features of our study. The use of WIO-MFA methodology enables one to convert a monetary input−output table into a physical interindustry Flow table involving an arbitrary number of Materials under full consideration of the mass balance. The results indicate that 40% of the PVC produced in Japan is exported (as resins and as products such as passenger motor cars), and the rest is accumulated mostly as capital stock. The largest share of accumulation goes to public construction in the form of plates, pipes, and bars, which are mostly hard-PVC products.
-
waste input output Material Flow Analysis and its application to quantity metals
Journal of The Japan Institute of Metals, 2006Co-Authors: Shinichiro Nakamura, Kenichi NakajimaAbstract:This paper develops a theoretical model of Material Flow Analysis (MFA) within the framework of the Waste Input-Output model (WIO) (Nakamura and Kondo). The model is developed based on two fundamental ingredients: yield ratios and the degree of fabrication. In manufacturing process, multiplication of physical inputs by the yield ratios gives the portion that enters physical outputs, with the rest being discarded as process waste without entering outputs. In input-output Analysis, the degree of fabrication can be visualized as triangularity of the input coefficients matrix (goods of lower degree of fabrication can enter those of higher fabrication, but the reverse does not hold), which is known to emerge through an appropriate reordering of sectors. Application to the Japanese IO data indicates that the model can provide accurate estimates of the weight as well as the composition of metals (Fe, Cu, Pb, Zn, and Al) used in a passenger car. The model is also used to estimate the major final use categories (household consumption, public consumption, capital investment, inventory investment, and export) of metals.
-
waste input output Material Flow Analysis of metals in the japanese economy
Materials Transactions, 2005Co-Authors: Shinichiro Nakamura, Kenichi NakajimaAbstract:This paper develops a theoretical model of Material Flow Analysis (MFA) within the framework of the Waste Input–Output model (WIO) (Nakamura and Kondo). The model is developed based on two fundamental ingredients: yield ratios and the degree of fabrication. In manufacturing process, multiplication of physical inputs by the yield ratios gives the portion that enters physical outputs, with the rest being discarded as process waste without entering outputs. In input–output Analysis, the degree of fabrication can be visualized as triangularity of the input coefficients matrix (goods of lower degree of fabrication can enter those of higher fabrication, but the reverse does not hold), which is known to emerge through an appropriate reordering of sectors. Application to the Japanese IO data indicates that the model can provide accurate estimates of the weight as well as the composition of metals (Fe, Cu, Pb, Zn, and Al) used in a passenger car. The model is also used to estimate the major final use categories (household consumption, public consumption, capital investment, inventory investment, and export) of metals.