Comprehensive Material Flow Research Articles

Resolving complexity: Material flow analysis of a national wood flow system integrating the versatility of wood

AbstractA systemic understanding of the use of wood resources is required to defossilize society and promote bio‐based developments. This study provides a novel approach to represent a comprehensive material flow analysis (MFA) spanning the entire wood value chain; encompassing wood harvest to products, use in society, collection, reuse, recycle, energy generation, and trade. By recognizing wood as a complex material, with changing properties throughout its lifespan, we developed a method where we employed a color‐coded system for processes (27 boxes) and 110 flows to symbolize distinct life stages and the dynamic characteristics, including 23 different trade flows. The wood processes and flows are categorized (11 categories) into different wood types (e.g., softwood and hardwood) and harmonized to include all available data on each single step of the wood life cycle, improving data traceability and visualization, and allowing for replicable analysis with respective data noted for each process and flow. Methodological obstacles due to different units, uncertainty of flows, and discrepancies in data are addressed and adjustments proposed. Switzerland was chosen as a case study as a large number of various types of data were available to perform the analysis. The categorized and harmonized flows of woody biomass mapped and analyzed in the MFA provide a comprehensive basis to identify and recommend avenues to increase cascading use of wood as a carbon sink, by considering relevant aspects like the network of flows and processes, the quality and availability of the woody biomass, and the organization of the industry.

Plastics in the Indian economy: a comprehensive material flow analysis

AbstractPlastic is valued for its flexibility to be utilized in different applications, yet it poses a significant threat to our environment because of mismanaged plastic waste. India’s compound annual growth of plastic consumption has been around 7% for a decade. Despite this significant growth, there has not been a comprehensive study of Indian plastic flows since 2000. This work presents a 20-year update, detailing plastic production, consumption by all plastic types and sectors, and the overall material flow for 2018–19 to fill the gap in the data on post-consumer plastic flows. The analysis reveals a total plastic production of 19.3 Mt, 22% of which is Polyethylene as the most wildly used plastic. The total mass of plastic in products distributed in various applications is 23.9 Mt. Key sectors for plastic consumption are Packaging (30%), Textiles (17%), and Buildings and Construction (16%). Plastic waste generation is 15.5 Mt, primarily from packaging and textiles. Only 13% of this plastic gets recycled, 46% is mismanaged, and the rest incinerated or dumped. The study’s unique nationwide, mass-balanced, transparent approach offers a rigorous reference point for decision-makers. Yet, the lack of reliable data is the main barrier to design, implement, and monitor of policy interventions.

From expansion to efficiency: Machine learning-based forecasting of Japan's building material stocks under demographic declines

Japan's unique demographic trajectory, marked by population decline and aging, coupled with continued urbanization, presents distinct challenges for aligning built environment capacity with resource efficiency. This study aims to investigate the historical evolution and project future scenarios of building material stock (MS) and their spatial distribution across Japan's three major metropolitan areas. Through a comprehensive material flow and stock analysis, the historical accumulation of building materials from 2009 to 2020 was quantified, revealing a dominance of concrete and an increasing overall stock. The contributions of various driving factors to changes in construction areas were explored, identifying population dynamics as the predominant influence. Leveraging shared socioeconomic pathway scenarios (SSPs), this research forecasted building floor area and MS until 2050 under five distinct SSPs. The results indicated an overall reduction across all scenarios, yet with a continued concentration in high-density urban cores. The substantial gap between the highest and lowest projected MS scenarios highlighted opportunities for material conservation and emission reductions through sustainable practices. Sustainable urban development in densely populated regions necessitates a balance between infrastructure provision and environmental conservation, while in sparsely populated areas, the focus shifts to the efficient management and utilization of vacant properties and materials to cope with the impacts of significant population declines. By offering insights into the building floor area and MS implications of Japan's demographic changes, this study underscores the necessity of sustainable urban planning and resource management strategies to navigate the challenges posed by demographic shifts, ultimately contributing to sustainable development and environmental conservation goals.

Advancing sustainability in China's pulp and paper industry requires coordinated raw material supply and waste paper management

As the largest global producer and consumer of pulp and paper, China faces significant sustainability challenges in fiber supply and waste paper management. A comprehensive material flow analysis of China's pulp and paper industry (CPPI) is needed to understand the interaction between raw material supply and waste paper management. Here, we construct a closed-loop material flow analysis model for CPPI, examine the evolution patterns of material metabolism from 1990 to 2019, and explore the demand for paper production, waste paper recycling, and virgin fiber supply in 2030 and 2050 under multiple scenarios considering critical factors. Results show that the industry has undergone rapid expansion, increased material use efficiency, and a shift towards recycled pulp from 1990 to 2019. China's paper demand will grow to 186 Mt in the next 30 years, resulting in a significant increase in both demand for fibers (173 Mt) and the generation of waste paper (138 Mt). To ensure a sustainable fiber supply for CPPI, domestic waste paper recycling needs to be prioritized. However, attention should also be paid to the availability of virgin pulp supply and proper disposal of organic solid waste. Proper management of these factors is crucial for achieving a circular economy in the industry and reducing its environmental impact. The findings highlight the importance of addressing both raw material supply and waste paper management for CPPI's sustainable development.

MECHANICAL VIBRATION AND SHOCK MEASUREMENT OF MATERIAL FLOW DEVICES AND SYSTEMS

The article deals with the measurement and analysis of the vibration of material flow devices and systems. This work has been done to find out if and in what form kinetic energy arises in comprehensive material flow processes. In the first chapter the theory of vibration measurement from periodic vibration to transient effects will be described using their physical and mathematical foundations. In the second chapter will present the results of the large-scale measurements. A special focus is on the natural frequency of the individual material flow devices. It has to be examined whether it is a certain useful frequency of technical units such as trucks, conveyor belt, etc. egsist over the entire supply chain. At the beginning of the article, the theoretical basics of metrology will be described, then the results will be presented and then the results will be summarized and evaluated. At the very end, an outlook is given about the further steps of the work.

On the importance of linking inputs and outputs in material flow accounts. The Weight of Nations report revisited

The influential Word Resources Institute report The Weight of Nations of 2000 called for additional research effort to understand linkages between primary material inputs and output of waste and emissions in material flow accounts. The report proved highly influential in driving efforts toward methodological harmonization of national material flow accounts but had little impact in triggering additional study into comprehensive material flow accounts and material balances for national economies. In this research we test the feasibility of linking inputs to outputs by establishing material flow balances for five countries including Germany, Japan, the United States, China and Australia using available statistical data and agreed calculation methods. While statistics for emissions to air are well documented, statistics for solid waste are usually incomplete and for many countries are of poor quality. We employ stock and flow modeling to determine the “waste potential” of a national economy, which can be used to validate statistically reported waste flows. We ask whether the accounts could be up-scaled to a global dataset and discuss challenges and limitations of such an approach; we also revisit the findings of the WRI report and find that methodological improvements to material flow accounting yield more reliable results than could be achieved two decades ago. Unifying input and output accounts in one coherent framework, i.e. a material balance, allows alignment of the policy domains of resource efficiency, greenhouse gas and pollution abatement, and waste minimization.

Sustainability indicators from resource flow trends in the Philippines

The topics of resource efficiency, pollution reduction and waste minimization have become important global policy goals and have gained prominence in developing countries in the context of the new Sustainable Development Goals. These pose challenges to the policy community in the formulation of plausible and ambitious targets for resource use, greenhouse gas emissions and waste. To bridge this gap, we utilize the material flow indicators derived from standard MFA methodology to show trends in material use, waste and emissions in the Philippines. We find that direct material inputs in the Philippines grew at 2.4% yearly, from 293 million tonnes in 1980 to 661 million tonnes in 2014. Domestic processed output, or materials released to environment has tripled from 96 million tonnes in 1980 to 260 million tonnes in 2014, with 89% as emission to air. The environmental Kuznets curve shows that the growing economy entails greater pressure to the environment. Net additions to stock grew slower than waste and emissions which is testament of a lack of infrastructure investment in the Philippines. Such a comprehensive material flow account responds to the information requirements of a modern environmental policy stance that looks at economy and environment simultaneously and has not previously been available. These findings call for policies to increase resource efficiency and improvement on recycling system, strict implementation of policies related to solid wastes management, mitigating air emission, and wastewater. The new dataset also shows slow progress in achieving SDG targets 8.4, 12.2 and 12.5.

A Comprehensive Material Flow Account for Lao PDR to Inform Environmental and Sustainability Policy

SummaryModern environmental and sustainability policy that acknowledges the linkages between socioeconomic processes and environmental pressures and impacts, and designs policies to decouple economic activity from environmental pressures and impacts, requires a sophisticated and comprehensive knowledge base. The concept of industrial metabolism provides a sound conceptual base, and material flow accounting—including primary material inputs and outflows of waste and emissions—provides a well‐accepted operationalization. Studies presenting a comprehensive material flow account for a national economy are rare, especially for developing countries. Countries such as Lao People's Democratic Republic (Lao PDR or Laos) face dual objectives of improving the material standard of living of their people while managing natural resources sustainably and mitigating adverse environmental impacts from growing resource throughput. Our research fills a knowledge gap, presents a comprehensive account of material inputs and outflows of waste and emissions for the Lao PDR national economy, and applies the accounting approach for a low‐income economy in Asia. We present a material balance for the years 2000 and 2015. For this research, we used data from Lao PDR national statistics and the accounting guidelines of the European Statistical Office (Eurostat), which pioneered the use of material flow data as part of its official statistical reporting. We demonstrate the feasibility of the accounting approach and discuss the robustness of results using uncertainty analysis conducted with statistical approaches commonly used in the field of industrial ecology, including Gauss's law of error propagation and Monte Carlo simulation. We find that the fast‐changing scale and composition of Lao PDR material flows, waste, and emissions presents challenges to the existing policy capacity and will require investment into governance of changed patterns of material use, waste disposal, and emissions. We consider the data analysis sufficiently robust to inform such a change in policy direction.

Evaluation of Environmental Performance Based on Proximity to Bat Associated Resource Utilization and Emission Values: A Case Study in a Steel-Making Industry

Best available techniques reference documents (BREFs) that are drawn up as required by the European Union Industrial Emissions Directive (IED) describe best available techniques (BAT) as the most effective, advanced and applicable methods, preventing emissions to the environment and providing efficient use of resources. Iron and steel industry, which causes quite significant amount of resource depletion and waste production, is one of the industries within the scope of IED. In this study; environmental performance of an integrated iron and steel plant in Turkey was evaluated by comparing its resource utilization and emission levels with the BAT associated values. To this end, a comprehensive material flow analysis was conducted, all inputs (energy, raw material, water) and outputs (products, by-products, emissions) involved in all sub-processes in the facility were determined and specific emissions and resource consumptions were calculated. In general, the studied plant’ performance against BAT associated resource utilization and emission values was within the span defined in the BREF. Concerning specific water use and the emission load to the receiving waters, the plant’s performance was pretty good. However, the plant was found to be in need of making additional efforts to reduce its dust emission load and specific energy consumption to achieve the BAT associated values. A total of 74 candidate BAT alternatives were identified and evaluated considering their adaptability to local conditions with regard to environmental benefits and technical practicability and economic feasibility. Among them, 36 alternatives were determined to be applicable BAT options for this plant to improve environmental performance and to reach BAT associated resource utilization and emission values.

Material flow analysis as basis for efficient resource management – the case of aluminium flows in Austria

Aluminium (Al) consumption growth exceeded those of all other major metals over the last decades. The main driver for this development is the broad range of applications for Al and Al-alloys. As the growth in consumption went along with an increase of anthropogenic stocks and flows of Al, information about material cycles became a crucial issue in terms of resource management. In this study a comprehensive material flow analysis (MFA) of the flows and stocks of Al in Austria for the year 2010 is conducted. The focus of the presented Al balance is on data harmonization and plausibility checks, both based on extensive data and literature research. The stock of Al is derived from bottom-up calculations indicating a total stock of about 260 kg Al per capita with an annual growth of 11 ± 3.1 kg/cap yr in 2010. Total old Al scrap generation is calculated to be 7 ± 1 kg/cap yr. For considering data quality aspects of single input data an adopted method for uncertainty assessment has been applied to the different material flows. This allowed a consistent evaluation of uncertainties within the material flow model. Due to the substantial uncertainties associated with end-of-life Al flows and their significance for secondary Al production in Austria, a better data base is needed in order to evaluate and optimize national Al scrap utilization in secondary production. Therefore, a dynamic MFA model will be built for Austrian Al flows and, in conjunction with the results from the static analyses, will provide a reliable decision basis for future Al resource management.

A new, entropy based method to support waste and resource management decisions.

A new method is presented to quantify the potential of a system to concentrate or dilute substances. The approach is based on a comprehensive material flow analysis and Shannon's statistical entropy function that is transformed by a three-step procedure. The result is a new function that can be applied to any defined system with known mass-flows and substance concentrations. In combination with materials balances, the method yields quantitatively the Relative Statistical Entropy (RSE) and the Substance Concentrating Efficiency (SCE) of a given system. When applied to compare five solid waste incinerators of increasing technology levels, the method (1) gave evidence of the potential of modern incinerators to control material flows and (2) pointed to future directions for further improvement of incineration technology. Case studies demonstrate that the new tool is well suited to support and complement existing methods for decision making in waste and resource management such as LCA.