Waste Flows Research Articles

Material Flow and Waste Recovery in a Community-Based Waste Management System in Batu, Indonesia

Indonesian government has promoted to establish Community Based Waste Management (CBWM) in Indonesia to increase the resource recovery rate and to reduce the amount of landfilling waste in stead of conventional the waste management. In CBWM, recyclable materials are recovered by neighborhood communities and only the residual waste is landfilled. Although CBWM can contribute to the reduction of green house gas emission and conservation of resources, the effectiveness of CBWM on the reduction of waste is an clear due to a lack of detailed information about CBWM such as economic benefit, waste flow and its sustainability. The aims of this study are to identify the waste flow in common CBWM in Indonesia and to evaluate the effectiveness of CBWM for reduction of MSW carried to a landfill site. The TPS3R Dadaprejo Mandiri (DM-TPS) in Dadaprejo Village, Batu City, Indonesia was investigated as a case of CBWM. Waste composition was surveyed for 8 consecutive days on three separate occasions in 2021 and 2022. Each resource was weighed and measured at each step of the process to analyze waste flow. Monthly data summarizing the amount of each resource separated at DM-TPS was obtained from their records. Information about the amount of waste and resources collected by the 13 waste banks was obtained by interviewing the administrators of those waste banks. The amount of waste carried to DM-TPS during the first, second, and third surveys averaged 5.61, 6.65, and 5.40 t/day, respectively. Of the 9 categories of waste, the largest was the organic waste. Fruits and vegetables made up the largest percentage of resources followed by plastic bags. The average resource recovery rate was approximately 15.2%. However, the composition survey revealed that the potential resource recovery rate was approximately 39.5%. In order to increase of resource recovery rate, the corporation of households on simple source separation at home would be required.

Study of "Green Manufacturing" on Rural Crystal Coconut Sugar SMEs

Crystal coconut sugar production will produce waste which will have an impact on environmental pollution. Waste generated is liquid waste and solid waste. Waste reduction handling can applied to "green manufacturing" principle. Research aims are: (1) identify waste generated, (2) determine green manufacturing opportunities, (3) green manufacturing opportunities analyze feasibility, and (4) green manufacturing implementation determine priority. Research phase includes: (1) quick scan analysis, (2) material, energy and waste flows identification, (3) alternative green manufacturing opportunities, (4) feasibility analysis (financial, technical and environmental), and (5) determination green manufacturing implementing priority. Results showed that ant sugar production produces waste in excrement on sap form, ashes from combustion, energy loss, crystal nuclei, and spilled sugar. Green manufacturing alternatives that are technically, environmentally and financially feasible are ash into inorganic fertilizers utilization, replacing cooking furnace, modifying drying equipment, replacing process materials, repairing and modifying screening, drying and packaging equipment. Implementing green manufacturing priority alternatives indicates that main alternatives to implemented are repairs and screening, drying and packaging equipment modifications which are considered technical and technological capabilities good in criteria, finance, human resources (HR), and environment. These results indicate that "Green Manufacturing" in rural SMEs crystal coconut sugar to increase global competitiveness "Green Economy".

Dynamic Plastics Flow Analysis for Korea between 1982-2020

Objectives : This study analyzed Korea’s plastic flows and stocks over the past 40 years to provide a quantitative basis for the nation’s plastic management and circular economy.Methods : Dynamic material flow analysis was conducted to quantify plastic flows across lifecycle stages and to estimate the size of in-use stocks. Focusing on 10 resins and 7 products, the analysis was conducted between 1982 and 2020 and at a national level. Production and trade flows were mainly quantified based on statistical and literature data, while consumption and waste flows were estimated using transfer coefficients. Different from static material flow analysis, waste flows were calculated based on the products’ lifetime distribution functions, and the changes in in-use stocks were estimated.Results and Discussion : Between 1982 and 2020, Korea produced 237 million tons of resins and provided 242 million tons of primary plastic products after the trade. Approximately 207 million tons of final products were consumed, 71% of which was generated as post-consumption waste and additional 3.8 million tons of waste was generated from the manufacturing stage. The amount of in-use stock of plastics was estimated to be 60 million tons. Of the 151 million tons of plastic waste, 24% was landfilled, 29% was incinerated and 47% was entered into sorting and recycling facilities. After sorting and recycling, 27 million tons were estimated to be recycled into products. From 1982 to 2020, per-capita plastic consumption increased from 15 kg to 150 kg, and per-capita waste generation increased from 2 kg to 139 kg. Packaging and containers, or PP and PE represented a major share of plastic consumption as well as waste generation. On the other hand, about half of the plastic stock was used for buildings and more than 50% of the building plastic stock was PVC.Conclusion : This study used a dynamic material flow analysis to quantify plastic flows over time, identify the composition of plastic waste flows according to resins or products, and estimate the size of in-use stocks. Such information on the waste composition and in-use stocks would be useful to improve recycling systems and estimate future waste flows.

DYNAMIC MECHANICAL PROPERTIES OF NATIVE ENDPLATE

A study of mechanical properties of native tissues is a great challenge in biomechanics. Especially, hardly accessible structures that play a very important role within a locomotive system. A study of a cartilaginous endplate (CEP) is just such a challenge. CEP is approximately 0.6 mm thin layer of hyaline cartilage between an intervertebral disc (IVD) and a vertebral body (VB). A calcification or any mechanical damage of CEP can cause restrictions of nutrition and metabolic waste flow inward and outward from IVD, respectively. Degenerative processes influence mechanical properties of the tissue. Due to very small thickness of CEP, instrumental nanoindentation seems to be suitable method for this task. This paper presents a study of time dependent viscoelastic properties of native porcine CEP using nanoscale dynamic mechanical analysis in the range of frequency from 5 Hz to 215 Hz. The storage moduli were obtained in the range from 11.78 MPa to 17.11 MPa. The loss moduli were obtained in the range from 2.96 MPa to 5.32 MPa.

Effect of inlet pipe design on self-cleaning ability of a circular tank in RAS

To improve the water reuse efficiency of circular recirculating aquaculture tanks in Recirculating Aquaculture Systems (RAS) this research investigated the effect of inlet pipe deployment distance d (the distance between the stream tube hole and the tank wall) and the inlet pipe deployment angle α (the acute angle between the inlet pipe jetting direction and the nearest tank wall) on the self-cleaning ability of the circular aquaculture tank under dual and single inlet pipe designs. First, waste collection experiments were conducted to figure out the preferable inlet pipe design based on the efficiency of waste collection. Then, flow field measurement experiments were carried out employing the Particle Image Velocimetry (PIV) technique to measure the flow field in the near bottom layer of the tank, and the essential mechanism of the inlet pipe deployment on the waste collection was explored by analyzing the flow field and the corresponding hydrodynamic characteristic indicators, such as the average flow velocity (vavg), the uniformity coefficient of water flow (DU50), and the water resistance coefficient (Ct). The results indicate that the variations of waste movement, flow filed and hydrodynamic indicators are consistent in both designs of dual inlet and single inlet, and merely differ in the absolute value. Based on the comprehensive analysis, the optimal performance of self-cleaning can be obtained at α=0°~10°, 20°~30°, 40°~50° for d=1/2 r, 1/4 r, and 1/50 r, respectively. At the same flow rate condition, the jetting velocity of the inlet pipe in the single inlet pipe design is significantly greater than that in the dual inlet pipe design, and the hydrodynamic characteristics of the waste collection are better. Therefore, in circulating water aquaculture production, it is recommended to design the inlet pipe in a similar aquaculture tank to the single inlet pipe with d=1/4 r, α=20°~30°, thus improving the self-cleaning ability of the aquaculture tank. The study results also provide a reference for adjusting the inlet pipe in circular recirculating aquaculture tank.

Material and Waste Flow Analysis for Environmental and Economic Impact Assessment of Inorganic Acid Leaching Routes for Spent Lithium Batteries’ Cathode Scraps

With the development trend and technological progress of lithium batteries, the battery market is booming. This means that the demand for lithium batteries has increased significantly, resulting in a large number of discarded lithium batteries. The consumption of plenty of lithium batteries may lead to the scarcity and expending of relevant raw material metal resources, as well as serious heavy metal environmental pollution. Therefore, it is of great significance to recycle valuable metal resources from discarded lithium batteries. The proper recycling of these valuable metals can reduce the shortage of mineral resources and environmental hazards caused by a large number of scrapped vehicle batteries. Recently, different systematic approaches have been developed for spent lithium battery recovery. However, most of these approaches do not account for the hidden costs incurred from various processing steps. This work is determined by the concept of material flow cost accounting (MFCA). Hence, in this research, a MFCA-based approach is developed for the leaching process of spent lithium batteries recovery, taking into consideration the hidden costs embedded in process streams. In this study, hydrochloric acid had the worst leaching efficiency due to its high solid-to-liquid ratio and the lowest acid concentration, so it was excluded in the first stage selection. It takes TWD 16.03 and TWD 24.10 to leach 10 g of lithium battery powder with sulfuric acid and nitric acid, respectively. The final sulfuric acid was the acid solution with the highest leaching efficiency and relatively low cost among inorganic acids.

Dynamic Simulation and Thermoeconomic Analysis of a Novel Hybrid Solar System for Biomethane Production by the Organic Fraction of Municipal Wastes

The anaerobic digestion of the organic fraction of municipal solid waste and the biogas production obtained from its stabilization are becoming an increasingly attractive solution, due to their beneficial effects on the environment. In this way, the waste is considered a resource allowing a reduction in the quantity of it going to landfills and the derived greenhouse gas emissions. Simultaneously, the upgrading process of biogas into biomethane can address the issues dealing with decarbonization of the transport. In this work, the production of biogas obtained from the organic fraction of municipal solid wastes in a plug flow reactor is analyzed. In order to steer the chemical reactions, the temperature of the process must be kept under control. A new simulation model, implemented in the MatLab® environment, is developed to predict the temperature field within the reactor, in order to assess how the temperature affects the growth and the decay of the main microbial species. A thermal model, based on two equilibrium equations, is implemented to describe the heat transfer between the digester and the environment and between the digester and the internal heat exchanger. A biological model, based on suitable differential equations, is also included for the calculation of the biological processes occurring in the reactor. The proposed anaerobic digestion model is derived by the combination of these two models, and it is able to simultaneously simulate both thermal and biological processes occurring within the reactor. In addition to the thermal energy demand, the plant requires huge amounts of electricity due to the presence of a biogas upgrading process, converting biogas into biomethane. Therefore, the in-house developed model is integrated into a TRNSYS environment, to perform a yearly dynamic simulation of the reactor in combination with other renewable technologies. In the developed system layout, the thermal energy required to control the temperature of the reactor is matched by a solar thermal source. The electrical demand is met by the means of a photovoltaic field. In this work, a detailed thermoeconomic analysis is also proposed to compare the environmental impact and economic feasibility of a biomethane production plant based on a plug flow reactor and fed by renewables. Several economic incentives are considered and compared to determine the optimal solution, both in terms of energy and economic savings. The plant is designed for the treatment of a waste flow rate equal to 626.4 kg/h, and the biomethane produced, approximately 850 tons/years, is injected into the national gas grid or supplied to gas stations. In the proposed plant, a solar field of an evacuated tube collector having a surface of approximately 200 m2 is able to satisfy 35% of the thermal energy demand while over 50% of the electric demand is met with a photovoltaic field of 400 m2. A promising payback time of approximately 5 years was estimated.

Model of multiperiod production-distribution for closed-loop supply chain considering carbon emission and traceability for agri-food products

PurposeThis study aimed to develop the integration of the multiperiod production-distribution model in a closed-loop supply chain involving carbon emission and traceability. The developed model was for agricultural food (agri-food) products, considering the reverse flow of food waste from the disposal center (composting center) to producers.FindingsThe results indicate that integrating the production and distribution model considering food waste recycling provides low carbon emissions in lower total costs. The sensitivity analysis also found that there are trade-offs between production and distribution rate and food waste levels on carbon emission and traceability.Research limitations/implicationsThis study focuses on the mathematical modeling of a multiperiod production-distribution formulation for a closed-loop supply chain.Originality/valueThe model of the agri-food closed-loop supply chain in this study that considers food recycling and carbon emissions would help stakeholders involved in the agri-food supply chain to reduce food waste and carbon emissions.

Policy implications for gaps in traditional plastic waste material flow analysis: Palmerston North, New Zealand

The Basel Plastic Waste Amendments reflect growing global concern about the illegal plastic waste trade as waste colonialism. Comprehensive analyses of plastic waste material sources, pathways, and fates are needed for effective plastic waste trade policy. Plastics waste flows from Palmerston North, New Zealand to Malaysia highlight potential gaps in plastic waste trade policies. The authors recommend strengthening New Zealand's national waste policy framework and the Basel Convention's Plastics Amendments by basing policy responses on critical transboundary plastic waste material flow analyses, establishing harmonized definitions including “recyclable” and “environmentally sound recycling”; regulating contamination thresholds and container inspections; and waste trade traceability, transparency, compliance, enforcement, and remediation; reclassifying fluorinated polymers and thermosets as “hazardous”; and prioritizing principles of prevention, proximity and precaution over future investments in the management of plastic waste.

Ocean-based sources of plastic pollution: An overview of the main marine activities in the Peruvian EEZ

Marine-based activities are a critical source of plastic waste into the ocean. This is particularly important in countries with a competitive fishing industry, such as Peru. Thus, this study aimed to identify and quantify the major flows of plastic waste accumulating in the ocean from ocean-based sources within the Peruvian Economic Exclusive Zone. A material flow analysis was elaborated to analyze the stock of plastic and its release to the ocean by a set of Peruvian fleets, including the fishing industry, merchant vessels, cruises, and boating vessels. Results show that in 2018 between 2715 and 5584 metric tons of plastic waste entered the ocean. The fishing fleet was the most pollutant, representing approximately 97 % of the total. Moreover, fishing gear loss represented the highest single-activity contribution, although other sources, such as plastic packaging and antifouling emissions, have the potential to become vast sources of marine plastic pollution.

Multi-objective two-stage stochastic optimization model for post-disaster waste management

Abstract Post-disaster waste management is one of the most crucial tasks in the recovery phase of the disaster cycle, and it was created to assist affected communities in returning to a stable state following a disaster. To develop an efficient post-disaster waste management strategy, this study presents a multi-objective two-stage stochastic mixed integer linear programming model for post-disaster waste management. The proposed mathematical model was developed based on a mixed strategy of on-site and off-site waste separation in the supply chain. This study aims to minimize not only the total cost and the environmental impact to provide waste flow decisions and choose collection and separation sites, recycling sites, landfill sites, and incineration sites throughout the supply chain under the uncertain situation. To solve a multi-objective problem, a normalized weighted sum method is used to find the solution. A numerical case based on realistic data is presented to validate and verify the proposed model. Based on the numerical example, the results demonstrated that the implementation of the mixed strategy for waste separation with the consideration of uncertain situations can reduce the total cost, balance the environmental impact, and determine the unexpected situation in the post-disaster waste supply chain efficiently.

The Importance of Digitalization for the Sustainability of the Food Supply Chain

This paper aims to define the negative impact of various indicators on the sustainability and functioning of the traditional food supply chain (FSC) in the segment of wholesale and retail activities and to propose a set of measures and incentives for the digitalization of its business processes. After a systematic review of the literature, the most common indicators significant for the functioning of the FSC were defined, primarily in the segment of wholesale and retail activities. Empirical research examined the influence of given indicators on the FSC. The obtained results showed that indicators such as poor coordination and transfer of information among FSC participants, food loss, economic performance, transaction costs, external elements, chemical and microbial contamination, and control of raw material, food, and waste flows significantly complicate the sustainability and functioning of the FSC. Based on the obtained results, a set of measures and incentives is proposed that the management of the supply chain should undertake to digitalize business processes, primarily in the segment of wholesale and retail activities. This paper also lists shortcomings of the research and gives guidelines for future research.

Dynamic estimation of end-of-life electric vehicle batteries in the EU-27 considering reuse, remanufacturing and recycling options

With the rapid promotion of electric vehicles (EV) in the European Union (EU), a new e-waste category is emerging, the lithium-ion batteries (LIBs). LIBs require proper management through circular economy business models. These include Remanufacturing, Reuse and Recycling of LIBs to extend their life before valuable materials are recovered. Material and substance flow analysis with a 3-parameter Weibull distribution function are employed to quantify all battery waste flows and their embedded materials. The available LIBs for remanufacturing will be 113–301 thousand (6–31 GWh) by 2024–2034, while the capacity of Second Life (2 L) LIBs will be 212–617 GWh by 2040. The available 2 L capacity in Germany and France could effectively cover the demand for energy storage for photovoltaic systems in these countries, which have the highest EV adoption in the EU-27. The recycled metals Li, Co, Ni and Cu could meet 5.2–11.3% of the demand for new materials considering the recycling efficiencies of the 2020 EU Battery Directive.

Identifying the impacts of trading construction waste across jurisdictions: a simulation of the Greater Bay Area, China, using non-linear optimization.

Local authorities worldwide are actively encouraging waste material trading within their jurisdictions as a promising strategy to develop a more circular economy. Construction activities consume natural resources intensively and generate massive solid waste. With proper ex-post treatment, the waste materials can be recycled or even directly reused, hence contributing to the circular economy. Using the Hong Kong-Macao-Guangdong Greater Bay Area (GBA) as the context, we simulate the impacts of a construction waste trading market on the waste flows and the resulting monetary exchanges. Our model views each city as a representative agent that maximizes the benefit of conducting waste recycling. The interactions of their profit-seeking behavior will lead to optimized overall social costs. We then solve this problem using a non-linear optimization algorithm. The simulation shows that with a fully operational market, the traded waste materials amount to 1253.84 million m3, covering 82.36% of GBA's total construction waste generation in a typical year. The monetary transactions equal to US$38.41 billion. Such huge payments present a great opportunity for the GBA cities to develop their recycling industries. In addition, we argue that although increasing public pressure is effective in reducing inequalities in the final waste distribution, it also results in fewer financial transactions flowing to less-developed cities, which reduces their funding for developing the circular economy.

Towards neodymium recycling: Analysis of the availability and recyclability of European waste flows

The world is facing a growing neodymium demand, creating the need for developing a recycling system to handle future waste flows. Recycling technologies are emerging, but the recycling system around them can only be established with knowledge about available end-of-life (EoL) products. Therefore, this study quantified neodymium waste in European countries using material flow analysis, and assessed the recyclability of major EoL products. For 2019, we find a waste flow of 7.7 kt Nd, consisting mostly of NdFeB magnets. HDDs represent a large current waste flow, while the demand for magnets in industrial applications is increasing. In the future, electric vehicle motors and wind turbines likely provide a source of neodymium with good recyclability. Consequently, there will be different product groups that determine the future waste volumes. To manage the changing waste flows, a neodymium recycling system should be developed with the product properties of future waste flows in mind. Meanwhile, the recyclability of products can be improved by addressing bottlenecks in the recycling chain.

What counts as infrastructural labour? Community action as waste work in South Africa

ABSTRACT Studies of waste work have largely focused on labourers who collect and process materials in exchange for money, including informal waste reclaimers and those now working precariously due to neoliberalization. Researchers have also drawn attention to who sorts waste in and beyond the household. Here we examine voluntary clean-ups as well as waste education in South Africa. State discourse encourages people to engage with the wastescape without framing this participation as work. Yet such engagements require people to act, and changing existing practices and expectations of who does what (and who is paid what) to make waste flow. We argue that understanding such activities as infrastructural helps to explain how the state seeks to enrol citizens into waste configurations, and understanding them as labour enables more capacious politics and claims to waste’s value.

Model predicting social acceptance behavior to implement ELV policy: Exploring the role of knowledge toward ELV policy on social acceptance in Malaysia.

Effective management of end-of-life vehicles (ELVs) represents a sound strategy to mitigate global climate change. ELVs are contaminants that pollute water, air, soil, and landscape. This waste flow must be adequately treated, but no proper rule oversees the disposal of ELV waste in Malaysia. This study aims to determine the extent of implementing the ELV policy and the social readiness in implementing environmentally friendly ELV disposal in Malaysia. The questionnaire seeks public input on critical ELV concerns such as public perception of the phenomena, environmental and safety standards, and recycling and treatment facilities. This research uses a cross-sectional design with 448 respondents in the survey. Fit models in structural equation modeling are evaluated using a variety of goodness-of-fit indicators to ensure an actual hypothesis. This study's advantages include the availability of representative samples and allowing for comparable and generalizable conclusions to larger communities throughout Malaysia. It is found that personal experience is significantly correlated with social readiness. The cause of ELV vehicles knowledge was the vital mediator, along with recycling costs knowledge. Thus, knowledge regarding ELV management costs is the most decisive mediation variable to predict public acceptance. The recommended strategy to reduce resentment and rejection of ELV policy is to disseminate information about the negative ELV impact on environmental and social sustainability.

Symbiotic integration of waste disposal capability within a city cluster: The case of the Yangtze River Delta

With the ongoing urbanization in developing regions, integrating regional waste disposal capability is challenging due to unbalanced economic development and rising environmental issues. This research proposed a multi-dimensional symbiotic integration of waste disposal capability. Applying data from the Yangtze River Delta (YRD) in China, we first explore the waste flows and interactions between cities to identify the possibility of inter-municipal collaboration based on the augmented gravity model. We then employ social network analysis to categorize the cities in the collaborative network of waste disposal into subgroups by functionalities. Finally, we proposed the top-down framework of symbiotic networks for waste disposal. Our findings indicate that YRD cities can be classified into four types according to their waste density and disposal efficiency: High-High, Low-High, Low-Low, and High-Low. We also identify three types of inter-municipal collaborative relationships: between high-density and high-efficiency cities, between high-density cities, and between high-efficiency cities. The city subgroups can be categorized into “high-efficiency clusters,” “high-density clusters,” and “hub clusters,” which pave the way for a shared or complementary urban symbiosis in the waste recycling industry. The division of roles among subgroups enables symbiotic activities within the city cluster. This paper extends the spatial scope of industrial symbiosis literature and has practical implications for transitioning to a circular economy in waste management of developing countries.

Insights into circular material and waste flows from c-Si PV industry

A material flow model for the production of Bifacial Selective Emitter 60-cell p-type Cz PERC (Passivated Emitter and Rear Contacted) glass-backsheet modules with aluminium frame was built. The selected module represents mature technologies in the PV industry and their manufacturing is considered to take place in China in a production cluster with an annual module capacity of 5 GWp. In a first step, data acquisition and validation for wafer, cell and module fabs took place. The data were used to generate the reference system lifecycle inventories (LCI) and extended waste databases for the reference wafers, cells and modules. A set of potential circularity actions, such as the vertical integration of the operations and waste revalorisation strategies, had been proposed and their environmental performance and cost assessed by means of a life cycle assessment (LCA) and a total cost of ownership (TCO). Our results show that 87% of the waste can be reduced and revalorised, this represents a circular flow of raw materials of 18,756 Mg per year from a 5GWp PV module production cluster. Environmental impact reductions of 0.6–2.3% are estimated for different impact categories. We also estimate a cost reduction potential of 2.59% from total module costs.

АНАЛИЗ ПРОБЛЕМАТИКИ ТЕКСТИЛЬНОЙ ПРОМЫШЛЕННОСТИ И ПУТЕЙ УТИЛИЗАЦИИ ЕЁ ОТХОДОВ В РОССИИ И МИРЕ

The authors analyze the flows of material waste from the textile industry and the efficiency of textile processing in the Russian Federation, justifying the need to use a circular economy model. There are the main tools for reducing waste in the textile industry, namely: reverse logistics, extension of the period of use of textiles, secondary use of textiles, secondary use of fabrics as raw materials for new products, wastefree production.