Material Flow Systems Research Articles

Consequential life cycle assessment of demolition waste management in Germany

ContextBulk mineral waste materials such as construction and demolition waste are Germany’s largest waste stream. Despite the availability of high-quality recycling pathways such as road base layers, waste concrete is predominantly recycled into lower-quality recycling pathways like earthworks or unbound road construction. This is due to low demand for recycled aggregates in road base layers and frost protection layers, especially in public procurement.PurposeThis study assesses the environmental consequences of increasing high-quality recycling of waste concrete in the near future to provide decision support for public procurement in Germany. The focus lies on climate change due to its importance for decision-makers. However, 17 other impact categories were assessed to avoid problem shifting.MethodsLife cycle assessment (LCA) is applied with background data from ecoinvent 3.9.1. Impact assessment was conducted at midpoint level using IPCC 2021 and ReCiPe Midpoint (H). Foreground data were taken from literature and expert interviews. In line with the goal of this LCA, a consequential modeling approach was followed to account for changes in the material flow system. Substitution creates a cascade effect previously omitted in consequential LCA studies, in which lower quality recycling materials replace higher quality recycling materials in their respective utilization pathways.Results and discussionIncreasing the high-quality recycling of waste concrete into road base layers causes a reduction in environmental impacts for all 18 impact categories, as it replaces natural aggregate and avoids backfilling of mixed mineral waste and excavated earth through substitution effects. Transport distances and ferrous metal recovery were identified as hot spots. Sensitivity analyses show that only transport is a significant issue.ConclusionIncreasing the high-quality recycling of waste concrete in Germany is recommended in terms of environmental impacts. Lower-quality recycling is environmentally feasible only in cases where the avoided transport distances for natural aggregates and backfilling are significantly lower than the additional transport distances for high-quality recycling.

DEVELOPMENT OF AN ALGORITHM FOR ADAPTING A MATHEMATICAL MODEL OF THE PROCESS OF MIXING AND MELTING COPPER CONCENTRATES

The paper describes the information base of the system, which is formed by algorithms of centralized control, automated analytical control system and control data of material flows. The data processing algorithm according to a special program generates additional information necessary to solve the control tasks of the system and includes algorithms for processing analytical data information, as well as data for monitoring material flows, calculations of additional electric furnace variables, loading of charge into furnace bunkers and technological variables by department. The simulation model of the functioning of the complex "technological process – control system" is implemented in the form of a package of interconnected software modules. The package implementing the simulation model is divided into three complexes: a set of programs for "Data collection and processing"; a complex for "Optimal process control"; a set of programs for "optimal energy regime management".

Synergy or Strife? Integrated assessment of economy–resource–environment development in Yangtze River Delta region based on material flow analysis and system dynamics

Synergy or Strife? Integrated assessment of economy–resource–environment development in Yangtze River Delta region based on material flow analysis and system dynamics

Partial Eruption of Solar Filaments. I. Configuration and Formation of Double-decker Filaments

Partial eruptions of solar filaments are the typical representatives of solar eruptive behavior diversity. Here we investigate a typical filament partial eruption event and present integrated evidence for the configuration of the pre-eruption filament and its formation. The Chinese Hα Solar Explorer Hα observations reveal a structured Doppler velocity distribution within the pre-eruption filament, where distinct redshift only appeared in the eastern narrow part of the southern filament region and then disappeared after the partial eruption, while the northern part dominated by blueshift remained. Combining the Solar Dynamics Observatory and Advanced Space-based Solar Observatory observations, together with nonlinear-force-free-field modeling results, we verify that there were two independent material flow systems within the preflare filament, whose magnetic topology is a special double-decker configuration consisting of two magnetic flux ropes (MFRs) with opposite magnetic twist. During the formation of this filament system, continuous magnetic flux cancellation and footpoint motion were observed around its northern end. Therefore, we propose a new double-decker formation scenario: that the two MFRs composing such a double-decker configuration originated from two magnetic systems with different initial connections and opposite magnetic twist. Subsequent magnetic reconnection with the surrounding newly emerging fields resulted in the motion of the footpoint of the upper MFR to the region around the footpoint of the lower MFR, thus leading to the eventual formation of the double-decker configuration consisting of two MFRs with similar footpoints but opposite signs of magnetic twist. These results provide a potential way to determine unambiguously the progenitor configuration of a partially eruptive filament and reveal a special type of double-decker MFR configuration and a new double-decker formation scenario.

Analysis of China's non-ferrous metals industry's path to peak carbon: A whole life cycle industry chain based on copper

Copper is an essential nonferrous metal, and the adjustment of its whole industry chain structure is conducive to realizing a carbon peak in the nonferrous metal industry. We have performed a life cycle assessment to calculate the carbon emissions of the copper industry. Based on the carbon emissions scenarios of shared socioeconomic pathways (SSPs), we have utilized material flow analysis and system dynamics to analyze the structural changes in the copper industry chain from 2022 to 2060 in China. The results show that (1) the flows and in-use stocks of all types of copper resources will increase significantly. The overall copper supply may meet demand around 2040–2045 due to secondary copper production potentially replacing primary copper production to a large extent, and trade supply is the primary pathway for meeting copper demand. (2) The total carbon emissions from the regeneration system are the smallest (4 %), followed by the production and trade subsystems, accounting for 48 %. The embodied carbon emissions from copper product trade in China have expanded annually. (3) Under the SSP scenario, the copper chain carbon emission peak will be achieved by approximately 2040. Based on a balanced copper supply and demand scenario, the recycled copper recovery efficiency must reach 84.6 %, and the energy structure (the proportion of non-fossil energy in electricity) must reach 63.8 % by 2030 to achieve the carbon peak target for the copper industry chain in China. The above conclusions indicate that actively promoting adjustments in the energy structure and resource recovery processes may help encourage the carbon peak of nonferrous metals in China by realizing the carbon peak of the copper industry.

Think before you throw! An analysis of behavioral interventions targeting PET bottle recycling in the United States

The United States generates 42 Mt of plastic waste each year and is one of the biggest contributors to ocean plastic waste. Consequently, plastic has become synonymous with the linear economy, and many scholars are studying and proposing circular economy solutions to mitigate plastic pollution. Recycling has received much attention from both social sciences and engineering as a circular economy strategy, but no study has yet quantified how behavioral interventions could asymmetrically affect different populations. This study combines agent-based modeling, material flow analysis, system dynamics, and life cycle assessment to assess the effect of four behavioral interventions on the collection rates of polyethylene terephthalate bottle waste, displaced virgin plastic manufacturing, and avoided greenhouse gas (GHG) emissions. Results show that, while behavioral interventions would require about 300–900 GJ of additional energy at end-of-life due to improved collection rates, they would avoid about 500–700 thousand metric tons of GHG emissions. Results also illustrate the importance of habits in disposal behaviors and show that different forms of interventions can be better adapted to particular social contexts than others. While the circular economy and its application to plastic waste should certainly not be restricted to recycling, this study demonstrates that improved collection rates and recycling technologies can contribute to reducing the amount of plastic waste polluting our oceans.

Potentials and limits of mechanical plastic recycling

AbstractPlastics consumption continues to steeply increase worldwide, while resultant waste is currently mostly landfilled, discarded to the environment, or incinerated. This significantly contributes to global warming and causes negative health and ecosystem effects. Increasing the circularity of plastics can reduce these impacts. This study investigated to which extent plastics' circularity can be increased by mechanical recycling. For this purpose, future scenarios involving increased waste collection, improved product design, and improved waste sorting were assessed. The system studied consists of 11 plastic types in 69 product groups consumed and arising as waste in Switzerland. By means of a material flow analysis, the amounts of consumption, waste, and secondary material utilizable in product manufacturing were quantified for the year 2040. For the waste not mechanically recycled, treatment situations mainly involving energy recovery in waste‐to‐energy plants and cement kilns were modeled. A life cycle assessment of the complete plastic material flow system was conducted. We found that the mechanical recycling rate calculated based on the utilizable secondary material can be increased to up to 31%. This can lower the plastic carbon footprint by one quarter (1.3% of today's total Swiss carbon footprint) compared to no recycling. Important barriers to a further increase of the recycling rate were inaccessibility, the large diversity of plastic grades, and contamination. The remaining impact at maximum recycling is mainly caused by polyurethanes, polypropylene, and polystyrene production. In conclusion, the potential of mechanical plastic recycling is limited, but it can, as one of several measures, contribute to combating climate change.

The impact of the wall insulation material and variable refrigerant flow system on building energy consumption and cost

The use of VRF system and insulation in building envelope are both considered as promising option to reduce energy consumption of a building. This study analysis energy saving potential of VRF system and building insulation using modelling and simulation of a typical office building. The model office building is simulated with the weather of Hyderabad, Sindh, Pakistan using EnergyPlus building simulation software. The simulation cases include conventional and VRF air conditioning systems with and without insulation to evaluate and compare the annual cooling and energy savings and payback period. Results showed that by replacing conventional air conditioner with VRF AC electrical power can be reduced by 42-45%. It is also noted that Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulations can save around 49.5, 51.4, 51.6, and 54.54% of electricity, respectively. In the case VRF air conditioner used with Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulation may reduce electricity consumption by 66.5, 67.4, 67.5 and 68.9 %, respectively. The payback period varies from 7 to 15 months. However, cellulose with VRF air conditioner has the least payback period of around 7 months. The longest payback period of around 15 months was noted for the un-insulated office building with VRF air conditioner. Despite having longer payback period, the combination of polyurethane insulation with VRF air conditioning system is the most efficient combination.

Industrial Symbiosis for Sustainable Management of Meat Waste: The Case of Śmiłowo Eco-Industrial Park, Poland.

This study presents the developing process of the Śmiłowo Eco-Park, located in the Noteć valley region (Poland), is a part of the biggest Polish agri-food consortium, from its initial small waste management company to its final structure as an eco-industrial park using industrial symbiosis methods. The industrial symbiosis applied in the Eco-park promotes a business model which covers the whole life cycle of the products starting from the plant growing by animal feed preparation, livestock breeding, meat preparations, meat-bone meal production from animal waste, and the use of pig slurry as a fertilizer. The Eco-park model is presented in the form of a system of connected stream flows of materials and energy covering the full lifecycle of products, from cereal cultivation, through the production of industrial feed, and poultry and pig breeding for the production of meat products. The solutions used include the prevention of environmental pollution through the modernization of existing processes, implementation of new technologies, reduction of waste and its reuse, recycling, and recovery of materials and energy, the substitution of raw materials with waste, and thermal treatment of waste and its use as biofuel. This case study allows for analyses of the organizational and technical key strategic activities which enable waste, including hazardous waste, to be transformed into valuable materials and energy. These activities have modified the system of material and energy flows through the value chain to realize the goal of allowing profitable management of waste according to circular economy methods and also indicates methods of supporting modifications of supply chains in terms of implementation of the industrial symbiosis business model according to its relationship with sustainable development, cleaner production, and circular economy models. EIP Śmiłowo annually utilizes 300,000 t meat waste, produces 110,000 t meat bone meal biofuel, uses 120,000 t of pig manure as fertilizers, produces 460,000 GJ bioenergy, eliminates 92,000 t CO2 emissions.

Finding high-impact intervention points for plastic recycling using an exploratory stock-flow model

With the growing impetus to increase the recycling of plastic waste, a more detailed understanding of the impact of different interventions on improving material circulation in the plastic value chain is needed. This paper uses an exploratory stock-flow modeling approach to analyze the impact potential of critical intervention points and their combinations for increasing circularity and reducing linearity in the Finnish plastic recycling system. The results show that interventions at all our selected intervention points—demand, collection, sorting, and processing—are needed to reach the best outcomes in terms of linear material flows. With uncertainty regarding international flows, collection- and sorting-targeting actions are most effective in avoiding the most pessimistic circularity outcomes, whereas demand- and capacity-targeting interventions have the potential to achieve the best optimistic circularity outcomes. The results contribute to previous research on plastic recycling by improving understanding of the critical bottlenecks and synergistic effects of supply- and demand-side interventions, as well as by supporting policy and industrial decision-making by drawing attention to effective combinations of interventions under uncertainty. The analysis also highlights how the coarse resolution structure of the material flow system governs the impact potential of intervention points, while many system parameters are less significant.

Digital twin architecture and sim-to-real gap analysis of a material transfer system in a remanufacturing environment

This paper presents a digital twin architecture for a material flow system as well as experiments to determine the sim-to-real gap between virtual models and their real counterparts. The architecture comprises three layers, namely the physical/logical layer, the cyber layer as well as the descriptive layer. Virtual and real assets are able to communicate on the cyber layer by means of OPCUA and the Asset Administration Shell (AAS). The virtual models are implemented in a physics-based simulation environment and allow the reuse of all control and application layer software modules of their real counterpart. In addition, the sim-to-real gap between a selected asset, namely the Transfer Unit is analyzed by means of a collision analysis of the material transfer of simple shaped objects. The results show similar behavior of the real and the virtual models. However, more effort is needed to accurately model the meshes of the collision elements to ensure realistic results.

OPTIMIZATION OF INTERNAL LOGISTICS USING A COMBINED BPMN AND SIMULATION APPROACH

The optimization of material flow systems requires a profound understanding of the underlying processes. Business Process Model and Notation (BPMN) is an established way of creating a process model that allows an interdisciplinary analysis and optimization. Quantitative exploration of systems using discrete-event simulation can help to enrich these insights. For that reason, this paper introduces a combined BPMN simulation approach that connects the advantages of both modeling frameworks. By synthesizing systems from generic modules, a comprehensive yet structured optimization process chain is developed. A case study evaluation based on key metrics for material flow.

Innovative Industry 4.0 Application Possibilities for Roller Conveyor Design

As a result of constantly changing customer demands, it becomes necessary to review the material flow systems operated by companies from time to time. The purpose of this is usually to minimize material flow losses and/or to ensure the necessary transport capacities. Revisions can affect intermittent and continuous operating material flow systems, and the combination of these. The thesis examines the areas where roller conveyor systems are used. Such systems are typically found in the food industry and the vehicle industry. The development of the 4th industrial revolution, its most important tools, and their applicability in the design and operation of roller conveyor systems will be presented. The article outlines a number of new research areas that may be of corporate interest.

Reducing food-system nitrogen input and emission through circular agriculture in montane and coastal regions

Reducing biogeochemical flows (e.g., reactive nitrogen [Nr]) is essential for a sustainable food system. Previous studies lack tailored strategies for Nr reduction in smaller-scale agricultural production. We developed a framework coupling material flow analysis and system dynamics modeling to establish a pathway for Nr reduction. We applied this framework to Fujian, southeast China, a mountainous and coastal province with fragmented small-scale agricultural and large-scale aquaculture production. Crops, livestock, and aquaculture accounted for 44.03%, 31.11%, and 23.69%, respectively, of Nr input in 2019. Thus, crop and livestock production accounted for approximately 70% of total Nr emissions. Only 8.66% of the total Nr inputs were recycled from livestock to cropland, and the Nr use efficiency of all three food categories was less than 20%. A balanced diet among residents increased (by 15.5%) Nr emissions, whereas minimized food loss and waste partially neutralized (reduced by 17.9%) the increase in Nr emission from dietary changes. By contrast, recycling kitchen waste, manure, and straw would eliminate 39.5% of the regional-food-system Nr emissions. We conclude that a circular agricultural system with Nr recycling is effective to reduce Nr input and emissions through more unified crop and livestock production in montane and coastal regions of Fujian.

Magnetic shape fabric analysis from syntectonic granites: a study based on the eigenvalue method

AbstractWe investigate the shape and strength of the magnetic fabrics (anisotropy of magnetic susceptibility (AMS) data) of various massive granitic plutons from different parts of India, using the eigenvalue method. The study aims to analyse eigenvalues and establish their relationship with various deformational attributes. It involves: (1) calculating eigenvectors and their corresponding eigenvalues from magnetic fabric datasets; (2) finding a link between the geometrical appearance of eigenvectors and the mechanistic issues involved with a specific deformation scenario; and (3) determining shape and strength parameters from the magnetic foliation data distribution.The statistical analysis for the unimodal magnetic fabric dataset of orthorhombic symmetry class implies that the plane, consisting of intermediate (V2) and minimum (V3) eigenvectors with pole V1, accurately traces the instantaneous stretching axis (ISAmax) of a particular material flow system under a pure shear regime. Moreover, for the distributions of similar symmetry and modality, we infer that the rotational characteristics of eigenvectors with respect to a fixed coordinate cause a distinct shift of such planes (V2–V3) from the ISAmax of a steady-state flow system under simple shear, where a substantial amount of rotational strain is involved. However, our findings also suggest that variation in symmetry and modality of magnetic fabric data distribution of different studied granitoids can directly influence the relative disposition of V2–V3 with respect to the direction of ISAmax. We conclude that eigenvalue analysis of magnetic fabrics is a powerful approach, which can be utilized while studying the salient deformational aspects of any syntectonic massive granitic body.

Actual problems of creating general logistics system in the Ukraine Defense Forces

Purpose: identify the main problems of the logistics as a management governing organ to support the defense system of Ukraine and to suggest ways to solve them.
 Design/Method/Approach: the main research methods are methods of statistical analysis, military-economic analysis, expert forecasting methods.
 Findings: from the mentioned problematic issues, there is a need to create the state logistics, as a system of logistics flow management and the definition of state standards, a clear conceptual framework for logistics, both state and military (military).
 Theoretical implications: in the article, the authors made an attempt and proposed to improve the system of material resources support and services of the Ukraine Defense Forces and create a united logistics system of the state, as management system of material, information and human flows which based on their optimization.
 Papertype: descriptive and analytical.

On the Fidelity of Computational Models for the Flow of Milled Loblolly Pine: A Benchmark Study on Continuum-Mechanics Models and Discrete-Particle Models

The upstream of bioenergy industry has suffered from unreliable operations of granular biomass feedstocks in handling equipment. Computational modeling, including continuum-mechanics models and discrete-particle models, offers insightful understandings and predictive capabilities on the flow of milled biomass and can assist equipment design and optimization. This paper presents a benchmark study on the fidelity of the continuum and discrete modeling approaches for predicting granular biomass flow. We first introduce the constitutive law of the continuum-mechanics model and the contact law of the coarse-grained discrete-particle model, with model parameters calibrated against laboratory characterization tests of the milled loblolly pine. Three classical granular material flow systems (i.e., a lab-scale rotating drum, a pilot-scale hopper, and a full-scale inclined plane) are then simulated using the two models with the same initial and boundary conditions as the physical experiments. The close agreement of the numerical predictions with the experimental measurements on the hopper mass flow rate, the hopper critical outlet width, the material stopping thickness on the inclined plane, and the dynamic angle of repose, clearly indicates that the two methods can capture the critical flow behavior of granular biomass. The qualitative comparison shows that the continuum-mechanics model outperforms in parameterization of materials and wall friction, and large-scale systems, while the discrete-particle model is more preferred for discontinuous flow systems at smaller scales. Industry stakeholders can use these findings as guidance for choosing appropriate numerical tools to model biomass material flow in part of the optimization of material handling equipment in biorefineries.

Исследование информационного взаимодействия между различными подсистемами на основе стандартов CCSDS при идентификации материальных объектов

Due to the increasing complexity of information processes, there is a need to develop models and methods of interaction between various subsystems, segments and, in relation to them, to develop methods for identifying ob-jects. The object of research is the process of accounting for the movement of material objects between different segments of complex systems, for example, between different segments of the international space station, between different segments of the material flow system or other segments of the Earth-Space system. Instruments and instrument complexes were chosen as material objects. Based on the performed study of data structure complexity levels, the necessity of development of identification systems for different segments of the material flow transportation system was substantiated. A new method is proposed and the results of practical experiments on the identification of material objects on the basis of CCSDS standard (CCSDS RFID Tag-Encoding Yellow Book) are considered. The hardware platform for accounting of tangible objects and information collection was selected radio-frequency readers and on-board computer networks represented by CCSDS 881.1-B-1 (Spacecraft onboard interface services - RFID tag encoding specification). RFID tags are used to identify tangible objects. To solve the problem of transferring information about material objects the developed model of information exchange and method of identification of material objects are presented, necessary fields and tag's memory bank structure are presented. In the process of describing the identification of material objects it is proposed to use a special alphabet ECMA-113 for data representation in the identifiers placed in the RFID tags. As part of the study, the simulation of information exchange between different subsystems during the transfer of information about material objects was conducted. The results of the experiments are presented, confirming that the universality of the alphabet lies in the possibility of simultaneous use of Latin and Cyrillic coding. For an estimation of efficiency of the offered models and modelling of a situation of an exchange of the information on material objects in wireless on-board networks separate independent subprogrammes of coding, decoding of identifiers of material objects have been developed and practical modelling of transfer of the big information volume between two various agencies (segments) is spent. The programmes were developed by the participants independently 
 of each other. On the basis of fulfilled modeling of information interaction and information transfer on material objects it was found that the error of data recognition does not exceed 6-7% and it does not increase with the increasing number of objects. The development results allowed to formulate a conclusion about the success of the experiment on the application of object identifiers based on CCSDS for airborne wireless networks, for the use of radio-frequency identification systems.

Limited utilization options for secondary plastics may restrict their circularity

Plastic recycling can provide environmental benefits by avoiding the detrimental impacts of alternative disposal pathways and enabling the substitution of primary materials. However, most studies aiming at increasing recycling rates have not investigated how the resulting secondary materials can be utilized in product manufacturing. This study assesses the future substitution potential of primary with secondary plastics, building on a material flow system of 11 plastic types in 54 product subsegments in Switzerland in 2017 with a recycling rate of 9%. In a prospective material flow analysis of a scenario for 2025, the collection rate of the plastic fractions collected in 2017 is increased to 80%. The secondary material flows are allocated to suitable uptaking product subsegments using a linear optimization. The maximum share of secondary materials utilizable in each product subsegment is estimated, whereby three sub-scenarios involving high, moderate and low allowed secondary material shares are modelled. Depending on plastic type and scenario, 21% to 100% of the secondary material gained can substitute for primary material, covering 11% to 17% of the total material demand. While the overall recycling rate could reach 23%, taking into account only the uptaken secondary materials a true recycling rate of only 17% results in the moderate applicability sub-scenario. Based on these results, the secondary material uptake can be said to constitute a limiting factor for increased future recycling. Therefore, thorough consideration of the possible secondary material application is a prerequisite for designing and assessing future recycling systems or for setting recycling rate targets.

Исследование и практическая реализация модели идентификации объектов систем учета материального потока на основе стандартов CCSDS

Although RFID hardware and software solutions for material flow and supply chain systems are widespread, their implementation today is realized at the local process and system level. When solving the problem of transmitting information about equipment between different systems, errors of inconsistency in data formats occur. This situation arises in the practical work of instrument making and space industry enterprises. There is a fragmenta-tion of the used information environments, models and methods. Today the development of new models and methods of identification of objects of material flow is important; they would provide data flexibility and the ability to integrate with existing RFID hardware systems, readers and other hardware systems. As a methodological support there have been chosen CCSDS standards, which offer solutions and development of hardware and software packages to solve the problem of identification of objects based on RFID tags. A systematic approach to representing the object identification levels has been offered and the need to develop a new system that is applicable for the identification throughout the life cycle of the object of material flow has been proved. The analysis of changing CCSDS standards in the development of hardware and software systems is presented to solve the problem of identification of objects based on RFID tags, the developed new model of data representation for the identification of the object is given, the practical implementation in the form of a subprogram is given. In addition, the possibility of adding new information about the object of the material flow is implemented, which has caused an opportunity to solve the problem of monitoring its movement in practice. The presented solution is versatile and can be used with a large number of well-known models of RFID tags. The identification system has been tested successfully so far and the results are presented in the standard CCSDS “Spacecraft onboard interface services – RFID tag encoding specification”.