Waste Supply Chain Research Articles

Identification of Waste Supply Chain Flow to Improve Performance

Semarang city has the amount of waste that piled up in the Landfill as much as 850 tons/day with the amount of unmanaged waste as is 100 tons/day. This phenomenon needs to be identified and evaluated for the flow of waste disposal from upstream to downstream. Therefore, the purpose of this study is to identify the flow of the waste supply chain and simulate it to determine the performance of waste handling in an area. The research method begins with a supply chain questionnaire which will then be statistically tested to be used as input for supply chain flow generation and simulation using Arena software. Based on the identification of the supply chain, the flow of the waste supply chain in the Wonosari area of Semarang is from households to the garbage dump to be taken to the landfill as far as 10 km. From the landfill, it is further processed into a selling value product. In this study, waste from the landfill is also the input material for the paving block production workshop (WPBP FT) at the Faculty of Engineering, Dian Nuswantoro University. Plastic waste will be used as a mixed material for making paving blocks. The supply chain simulation results using Arena show that the performance is good.

Bioprocessing of biowaste derived from food supply chain side-streams for extraction of value added bioproducts through biorefinery approach

Food chain-based waste is generated in tonnes globally and this has led to release of greenhouse gases, poor air quality, land and water pollution. Food wastes are generated in tremendous quantity globally from local producer to international consumers and traders. Authors have used systematic literature review to identify the research gaps, thematic areas, methodology, sustainable techniques and future directions of processing food supply chain waste. Research is focused towards utilization of food waste as source for recovery of value-added compounds through sustainable technologies. Food waste can be utilized to synthesis platform chemicals, nutraceuticals, sugars, bio-fuels, bio-gas and bio-char via thermo-chemical conversion, anaerobic digestion and fermentation processes. This paper summarizes and provides technical insights on achieving circular bio-economy via technological advances in food waste processing for enhanced recovery of value-added compounds and future industrial scale operations. The state of art perspectives of food waste valorization and market outlook of platform chemicals and other products provides profitable economy for the food waste generator. Food security requires holistic approaches for effective usage of resources with inter linked global policies.

Towards a sustainable organic waste supply chain: A comparison of centralized and decentralized systems

Proper disposal of Municipal Solid (MSW) waste is an important issue as it causes land, air, and water pollution. Organic MSW provides a habitat environment to insects and often it spreads dangerous diseases. Major reasons identified behind this as the non-separation of MSW at the source and lack of facilities (bins) in the appropriate place for collection of wastes. The present study has proposed an integrated three-stage model to provide a solution to the problem of (i) allocation of the bin for waste collection, (ii) allocation and comparison of centralized and decentralized composting plants, and finally, (iii) vehicle routing for waste collection. The proposed generic model is applied to an Indian city, Bilaspur located in the state of Chhattisgarh. From the results, it is observed that the first stage model provides an optimal number of bins required and allocation of it at minimum cost. Taking it as input for the second stage model, it identifies the best locations for centralized and decentralized composting plants. The result also reveals that decentralized composting plants are more economical than centralized plants. Finally, the third stage of the model identifies the vehicle routing for the waste collection considering both centralized and decentralized plants to minimize the cost. Further, sensitivity analysis is carried out on collection rate and participation percentage parameters to draw additional insights for better management of MSW.

Drivers for the adoption of integrated sustainable green lean six sigma agile manufacturing system (ISGLSAMS) and research directions

Due to the scarcity of resources, and the need for preserving the resources for the future generation, there has been significant growth in research and development in a sustainable market-focused manufacturing system, in particular with the view of product recovery, waste elimination, and landfill legislation. It has extended the responsibility of manufacturing organizations to include the recovery and safe disposal of their product, process, and supply chain waste, as well as, the adoption of a sustainable quick response manufacturing system, to produce sustainable customized products. A more compatible manufacturing system and strategy are required to meet these business goals. It is observed through literature that an integrated sustainable green lean six sigma agile manufacturing system (ISGLSAMS) provides a strong platform to meet all these business, societal and ecological needs under a single umbrella. However, many organizations opt for this strategy voluntarily and many do not. It is observed through a literature survey that through this strategy organizations improve their financial, market, social, environmental, operational, and sustainable performance. The main objective of this review is to identify the various drivers for the adoption of an ISGLSAMS, so that governments, stakeholders, and policymakers may plan the strategy for motivating the organizations for the ISGLSAMS. The review also discusses the key enablers and characteristics of ISGLSAMS, product, and strategy. The review also highlights the key characteristics, and clauses of each driver, and research areas for the drivers for the adoption of ISGLSAMS. The review also shows a performance measurement or performance benchmark framework for ISGLSAMS.

Pricing problem in a medical waste supply chain under environmental investment: a game theory approach

ABSTRACT This study examines the pricing and environmental investment problem for a medical waste supply chain, including waste generators, contractors, and disposal facilities. Unlike prior studies, different game structures are considered to study the interaction between supply chain players. The models are formulated using nonlinear optimization. To maximize supply chain players’ total profit, an analytical and closed-form approach is applied to determine the best service price and environmental investment. The numerical illustration confirms that investment in environmental factors increases the total profit of supply chain partners and an optimal extent exists. Medical waste generators are also willing to pay more to firms that incorporate environmental aspects into their disposal operations. Furthermore, according to the sensitivity analysis, the decision-making power of the contractor has no significant impact on its profitability.

Municipal solid waste supply chain management under an integrated optimization of sustainability targets

This research study presents a dynamic discrete optimization model for the treatment of municipal solid waste (MSW) with sustainability as an essential research objective. The optimization model screens capacity selections for MSW technologies over distributed sites with consideration of pretreatment biodrying technologies for waste calorific value enhancement. The choices for these MSW technologies and the network operation are described by binary and continuous variables, respectively. The MSW network economic seeks the maximization of the net present value (NPV). Key environmental impacts of MSW technology use as well as the impacts of MSW transportation are described by a minimization optimization problem. The social target of the MSW network considers the maximization of job creation. When applying the model to a case study, sustainability objective functions showed conflict in the results. Pareto optimal solutions are found from the multi-objective optimization model and a compromised solution is suggested for the considered case study.

Organizational enablers for sustainable manufacturing and industrial ecology

Due to the scarcity of resources, global warming, and rising energy prices, there has been significant growth in research and development in sustainable manufacturing. This has moved the responsibility of manufacturers to manufacture sustainable products in a sustainable manner focusing on product, process and supply chain waste during their life cycle. However, many organizations try to opt for this strategy, but due to price competition, focus on quality issues, and lack of integration of various enablers of sustainable manufacturing, organizations are not able to implement sustainable manufacturing strategically. The purposes (scientific value) of this paper are to (i) identify various enablers for sustainable manufacturing (ii) familiarize industrial professionals and SMEs practitioners with the sustainable manufacturing tools and practices (iii) enhance industrial ecology through sustainability gain (iv) enhance the organizational financial, market, social, environmental performance throughout the whole supply chain of manufacturing and product life cycle, for developing the better place of livelihood for the species and increasing GDP value of the nation (v) identification of associated future research directions. This study helps the stakeholders, practitioners and organizations to plan the strategic significance of each enabler for developing the pathway to achieve sustainability goals. This study contributes to a better understanding and holistic approach for sustainable manufacturing throughout the whole supply chain of manufacturing and product life cycle. It is observed through this study that for achieving sustainability goals in manufacturing, strategic holistic long-term streamlined planning along with top management commitment is essential. For sustainable manufacturing implementation, the roadmap has to be developed by the policymakers. Organization commitment for tools and practices is the key essential requirement for the successful implementation of sustainable manufacturing in the supply and value chain.

Drivers of industry 4.0-enabled smart waste management in supply chain operations: a circular economy perspective in china

Increasingly, circular economy (CE) has been adopted globally to operationalize supply chain sustainability. The development of industry 4.0 technologies provides a new opportunity to improve the effectiveness and efficiency of adoption of CE, in particular, from the waste management perspective. More recently, scholars acknowledge the need for more studies on industry 4.0 and CE-driven sustainability aspects in supply chains. This research aims to fill the literature void and make a contribution from the perspective of smart waste management in supply chains using industry 4.0-based CE operations. Eleven key drivers were identified through semi-structured interviews, administered to experienced supply chain practitioners in China. A fuzzy DEMATEL method was used to analyse the interrelationships among these key drivers. The results show that the most fundamental causal drivers of smart waste management are overcoming operational challenges, recovering value, speeding up operations, saving cost and improving profit. There is a virtuous cycle between market demand and the improving price-performance ratio of industry 4.0 technologies. Our findings are part of the development of a bottom-up approach to adopting smart waste management in supply chains. The interrelationships identified in this research provide valuable insights into driving forces. Organizations, policy makers and technology providers can apply these insights when utilizing industry 4.0 technologies to improve supply chain waste management in line with the CE principle, and to achieve supply chain sustainability.

Research on the Evolutionary Game of Construction and Demolition Waste (CDW) Recycling Units' Green Behavior, Considering Remanufacturing Capability.

At present, China has not yet formed an effective development model for the industrialization of construction waste. The level of construction waste treatment and resource utilization is still low, and recycled products also lack market competitiveness. In order to promote the effective development of the remanufactured construction and demolition waste supply chain better, and based on the present situation, this manuscript establishes a game model for recycling units in two different situations: with and without remanufacturing capabilities. However, most existing studies have determined that all recycling units have remanufacturing capabilities. In the first situation, the main players of the game are recycling units with remanufacturing capabilities and consumers. In the second situation, the main players of the game are recycling units without remanufacturing capabilities and the third-party remanufacturer with remanufacturing ability. Therefore, our research can ascertain the optimal strategy choices of both parties in the game under different return situations and discuss the impact of changes to related parameters through numerical simulations. The results show: (1) When the recycling unit has remanufacturing capabilities, corporate leadership and government supervision rate have positive effects on its evolution to strict manufacturing. Only a high supervision rate can effectively suppress the negative impact of speculative gains and drive the system to (strict manufacturing; positive). Furthermore, the higher the supervision rate, the faster the system will converge. Then, the consumer’s payment difference coefficient has a negative effect on the evolution of the recycling unit to strict manufacturing. The larger the payment difference coefficient, the faster the system will converge to a stable state (tendency to formal manufacturing; negative). (2) When the recycling unit does not have the ability to remanufacture, the government cost subsidy rate and the recycling unit’s effort profit coefficient have positive effects on the recycling unit’s evolution to the direction of effort. Meanwhile, the larger the profit coefficient of the recovery unit’s effort, the faster the system will converge. The conclusions obtained provide certain theoretical guidance for the decision making of CDW recycling supply chain recovery units and relevant government departments.

Redesigning the Municipal Solid Waste Supply Chain Considering the Classified Collection and Disposal: A Case Study of Incinerable Waste in Beijing

The output of municipal solid waste is growing rapidly, which has brought tremendous pressure to urban development. The supply chain of municipal solid waste (MSW) in China mainly contains three processes: collection, transportation, and disposal. The waste is sorted at the collection and disposed of according to the classification. However, it is mixed at the transportation stage. Mixed transportation remixes the separately collected waste, which seriously affects the disposal effect. The supply chain of MSW urgently needs to be redesigned to improve the MSW disposal effect. First of all, on the ground of the waste treatment situation, we redesigned the supply chain of MSW in China. Secondly, combined with the redesign of the MSW supply chain, this paper established the function allocation model for collection stations, making a collection station only gather one type of waste, and built the transportation path planning model for vehicles, reducing the impact of waste storage on residents. Finally, based on the data of Xuanwu District in Beijing, the supply chain redesigning practical example of incinerable waste was given. The supply chain redesigning model in this paper not only makes full use of the existing infrastructure but also improves the disposal effect of waste. The supply chain redesigning model has practical application value.

Growing e-waste management risk awareness points towards new recycling scenarios: The view of the Big Four’s youngest consultants

The e-waste sector is characterised by a rapid growth at global level and therefore involves an area not yet sufficiently investigated in its risk management dimension. This research fills the gap of the absence of a holistic approach to risk identification and assessment in e-waste management, suggesting a new Risk Awareness Indicator (RAI). An integrated Multi-criteria decision analysis (MCDA)-Analytic Hierarchy Process (AHP) is proposed to calculate the new index. Weights and values will be proposed by twenty Big Four’s youngest consultants (generation-Z and millennials). For e-waste, cyber risks related to personal data are critical in the collection phase, environmental risks in the transport phase, and financial and economic risks in the processing phase. Recycling scenarios pose less overall risk than landfill alternatives. The results can help policy makers to meet the circular economy targets set at the European Union level by implementing administrative and regulatory simplifications to support recycling supply chains and make them more efficient and resilient after the pandemic disruption. This work focuses on e-waste and the opinion of screenagers consultants, however the methodology used to design the RAI index makes it easy to replicate the analysis to other social settings and other waste supply chains.

Post-disaster waste management with carbon tax policy consideration

Generally, the activities of post-disaster waste management usually produce high carbon emissions, which can cause damage to the environment. However, the issue of carbon emissions in the post-disaster waste supply chain is neglected. Hence, this paper aims to propose a mixed-integer linear programming model to address the post-disaster waste processing supply chain network design problem with the consideration of a carbon tax policy. The proposed model is developed based on the concept of a mixed strategy of waste separation to reduce carbon emissions. Not only the carbon emission perspective but also the financial perspective for post-disaster waste supply chain management is determined in the objective function. The proposed model was verified and validated by employing a numerical example based on realistic data. Based on the numerical example, the results show that the implementation of a carbon tax policy with the mixed strategy for waste separation can reduce carbon emissions in the post-disaster waste supply chain efficiently.

Energy from food waste

Energy from food waste

Modeling and identification of suitable motivational mechanism in the collection system of municipal solid waste supply chain.

Many studies have identified that incentive, subsidy, and reward-penalty mechanisms improve the collection rate of recyclables and end of life products. But there is a lack of studies mathematical models and analysis of these mechanisms in the context of municipal solid waste supply chain. Therefore, in this study, models have been formulated for municipal solid waste supply chain (profit) considering government and collectors' profit under incentive, subsidy, and reward-penalty mechanisms. The study has analysed the models against the non-separation and separation scenario of waste. A numerical analysis is performed and observed that: (i) separation of waste at source along with incentive, subsidy, and reward-penalty mechanisms scenario improve the collection rate by 17%, 23%, 30%, and 45% compared to non-separated MSW. (ii) Incentive, subsidy, and reward-penalty mechanisms increases the total supply chain profit by around 9%, -36% and 18%. (iii) reward-penalty mechanism performs better than incentive and subsidy mechanism by providing the high supply chain profit (18% and 85%) and collection rate (22% and 15%) comparatively. Further, sensitivity analysis carried out to understand the behaviour of the models against the key parameters. The study also develops interesting propositions and proved for a better understanding of the models. From results, some key managerial insights have been drawn and a few future scopes of the study are presented.

Valorisation of grape stalks and pomace for the production of bio-based succinic acid by Actinobacillus succinogenes

Valorisation of food supply chain waste for the production of bio-based platform chemicals will facilitate the transition to the sustainable bio-economy era. To this end, a novel process has been developed for the conversion of grape pomace and stalks into bio-based succinic acid. Free sugars (2.55 g/100 g), a phenolic-rich extract (185.75 mg gallic acid equivalent per g extract with Antioxidant Activity Index of 1.03) and lipids (8.2 g/ 100 g) were initially extracted from grape pomace. Residual grape pomace solids were subsequently mixed with grape stalks (1:1 ratio) and treated with sodium hydroxide (1%, w/v) for lignin removal. The residual solids were treated with varying H2SO4 concentrations (3–10 %, v/v) followed by enzymatic hydrolysis using different dosages of cellulases and β-glucosidase leading to the release of 22.7 g glucose per 100 g remaining solids (48 % cellulose hydrolysis). Actinobacillus succinogenes fed-batch cultures carried out with the crude hydrolysate as fermentation medium and free sugars from grape pomace as feeding solution resulted in 40.2 g/L succinic acid concentration with a yield of 0.67 g/g and productivity of 0.79 g/L/h. This study proposes for the first time a sustainable process for valorising grape pomace and stalks for efficient bio-based succinic acid production integrated with the extraction of value-added fractions.

Sustainable Green Supply Chain Management and Waste Management in Construction Industry

Sustainable Green Supply Chain Management and Waste Management in Construction Industry

Towards Circular Economy through Industrial Symbiosis in the Dutch construction industry: A case of recycled concrete aggregates

Since 95% of the Construction and Demolition Waste (CDW) is down-cycled and the material value is not effectively recovered, the Dutch construction industry strives for implementing Circular Economy (CE). From the recycling/reusing perspective, a key enabler towards CE is Industrial Symbiosis (IS). Although IS has been widely applied in manufacturing industries, its implementation is unclear in the construction industry. Particularly, the potential IS economic convenience is hard to predict in the highly fragmented construction supply chain. This study explores the IS based on the Recycled Concrete Aggregates (RCA) in the context of a concrete waste supply chain in the Twente region of the Netherlands. The research tackles with the CE challenge of lacking economic incentives by investigating the Industrial Symbiosis Network (ISN) emerged by replacing Primary Concrete Aggregates (PCA) with RCA. An Agent-Based Modelling (ABM) approach is proposed by integrating Geographic Information Systems (GIS) to present the dynamic supply-demand of RCA. Besides, supply chain actors are simulated as negotiable agents in a platform model to reveal the IS collaboration dynamics under different economic scenarios. It is found that the IS exists in the construction industry but only in an implicit manner because the RCA treatment requires the collaboration of multiple actors across substantial temporal and spatial differences. The study enriches the IS taxonomy by defining Implicit IS and provides instruments to support the decision-making of business collaborations and policy-making for a circular construction industry.

Optimizing the polymer waste supply chains based on circular economy

The paper shows the results of an empirical study on the optimization of polymer waste supply chains based on the circular economy in Ukraine. The research shows that the main links in the activity should be harmonized for quality and quick optimization of polymer waste supply chains, including the processes of collecting, sorting, treatment, processing, and recycling of resources for maintaining the quality by total cost reduction. The research argues that the circular economy that stipulates the easy processing, recycling, disassembling, and restoring of products replaced the traditional linear model “take, produce, and throw out” that has dominated the economy by now. The study shows that the transformation of supply chains in production ecosystems forms competitive advantages at the enterprises that allow them to be more productive through efficient use of resources.

Microwave-assisted extraction and matrix solid-phase dispersion as green analytical chemistry sample preparation techniques for the valorisation of mango processing waste

Food supply chain waste is consisted not only by the visible part generated in commercial and consumer steps, but also by the residues generated during harvesting and processing of food-related plants. A great part of these materials is unavoidable, meaning that they cannot be prevented trough waste reduction policies currently being pushed to achieve better food distribution and end hunger across the globe. Valorising this waste stream may help increasing stability in the food sector, having not only a financial gain, but also an environmental and social positive impact. Mango Processing Waste (MPW) is one of the examples of how such residues are poorly explored, as its large volumes contain several valuable substances, such as bioactive compounds, that can be used in the food industry as ingredients and as nutraceuticals, pesticides in agriculture, biocides and other uses. The flavonol hyperoside and the xanthone mangiferin are the main secondary metabolites found in MPW, being reported to have biological activities that range from antioxidant to pesticidal and pharmacological potential uses. In a broader context considering the use of MPW in a biorefinery and circular economy concepts, sustainable processes are required to meet future sustainability parameters. Therefore, Microwave-Assisted Extraction (MAE) and Matrix Solid-Phase Dispersion (MPSD), two sample preparation techniques, were discussed and studied as proposed green and sustainable methodologies for the extraction of mangiferin and hyperoside from MPW. Doehlert and Box-Behnken experimental designs were used to help assessing the influences of the variables of each technique, allowing to employ a Response Surface Methodology (RSM) to visualize the best conditions and calculate optimum parameters. Fast extraction was achieved using MAE, which obtained maximum response of 261.39 mg kg −1 of mangiferin and 244.44 mg kg −1 of hyperoside. Higher yields were obtained using MSPD methodology, with an extraction yield of 352.90 mg kg −1 and 398.52 mg kg −1 of mangiferin and hyperoside, respectively. The conditions that allowed maximum simultaneous extraction concentrations were calculated using the desirability function. MAE and MSPD methodologies were compared, with an overall conclusion that both were adequate for the determination of the two analytes and can be further studied to be used in higher scales.

Textile supply chain waste management in China

The development of the textile industry directly leads to the growth of pre-consumer waste generation. Investigating textile supply chain waste management in China is necessary to determine potential measures with the purpose of waste reduction from textile production. In this study, 396 textile supply chain factories in China were surveyed to evaluate their waste generation (quantity, waste streams, and disposal methods), waste management (practices, financial investments, expenditures and revenues), and difficulties and challenges in waste management. The results showed that the surveyed factories generated 331.88 t of the total waste in 2015, including an average of 15.32 t of hazardous waste, which accounted for 4.62% of the total waste. The average waste per ton of production in these factories were 0.14 t. The primary waste streams in the Chinese textile supply chain included sludge accounting for 41.67% of the total waste, followed by food/human (28.57%), textile (13.67%), other domestic (4.57%), cardboard/paper (4.30%), and chemical (3.15%) waste. Accumulated data related to the production of as sludge, other hazardous, and textile materials was sufficient; however, data related to human activities was inadequate. Only 35% of sludge was recycled in the textile industry. To improve the reuse ratio of sludge, it is necessary to classify the sludge with respect to its source. In the textile supply chain, 80% of textiles were recycled. Compared with post-consumer waste, the recovery rate of pre-consumer textile waste was high with a good recycling quality. Less than 20% of the food/human and domestic waste were recycled; most of these waste were mixed with other waste and collected by city municipalities in 2015. Further, there were a few recycling programs in mills. Our results also showed that the factories invested three times more in infrastructure than that in administrative expenditures, and that the revenues were nearly 50% of the total investments. Over 80% of factories were found to have an extended payback period (more than 10 years) for waste investments, and few factories could recoup the money invested in a short time frame. Among them, we found that more attention needs to be paid to financial problems of waste management in small-sized factories. Investing positively should be adopted by the government and brands. Based on our observations, the predominant problems encountered in waste management included a lack of technical support, lack of support from the government and brands, and shortage of qualified recycling contractor. To resolve these issues, collaborations between the government, brands, and suppliers is imperative. In general, China exhibited more sufficient waste management compared to Cambodia, Vietnam, South Korea, and Myanmar. However, waste management in China and these other countries have great potential for improvement. The results presented herein can provide information for policymakers as well as on systemic waste management in the textile industry.