Viability of a circular economy for space debris.

The orbital debris population is rapidly growing, increasing the chance of a Kessler-style collision event. We report a novel method for the production of estimates for the total monetary value of all debris objects and total mass of all objects currently in orbit. The method was devised using debris object data from the European Space Agency's DISCOS dataset, classified via a decision tree. 'Reuse' and 'scrap material' scenarios were developed. A high-end estimate for reuse shows a net value of $1.2 trillion. Median and low-end net value estimates of $600 billion and $570 billion, respectively, are probably judicious. A scrap material scenario produced a high mass estimate of 19,124 tonnes, a median of 6,978 tonnes and a low estimate of 5,312 tonnes. Development of in-orbit services will be crucial to solve the orbital debris problem. A future circular economy for space may be financially viable, with potentially beneficial consequences for risk reduction; resource efficiency; additional high-value employment; and climate-change knowledge, science, monitoring and early warning data.

How much does it cost to collect recyclable and residual waste in medium-income countries? A case study in the Chilean waste sector.

Improper municipal solid waste (MSW) management leads to contamination of water, soil and air with negative impacts on human health. Moreover, not dealing with residual waste has huge implications for meeting circular economy targets. Understanding how much it costs could lead to a better quality of service and boost environmental sustainability. This study estimates an input distance function using econometric techniques to measure the technical efficiency of the MSW sector in Chile. This approach further allows us to estimate the shadow price of residual waste in terms of total costs. The results indicated that the average technical efficiency of the waste sector was 0.592. This means that the potential savings in costs and residual waste among municipalities could be at the level of 40.8%. Large divergences among municipalities were found since efficiency scores ranged between 0.029 and 0.863. It is found that for 53% of the municipalities evaluated, efficiency scores varied between 0.61 and 0.80. On average, the cost of reducing residual waste was 81.10 US $ per kilogram. This means that on average the cost of preventing one more kilogram of residual waste not being collected and recycled was 81.10 US $. It was also found that on average as population density increased, the shadow price of residual waste increased as well.Implications: The study provides a methodology that allows the policy makers to estimate the efficiency of the solid waste sector where limited available statistical data usually exists in developing and medium-income countries. They have the opportunity to understand what drives costs and identify the best and worst performers. This information is essential to develop local initiatives to enhance waste recycling and therefore, achieving the targets established at national level. Managers can also see if there are other operating factors that could influence performance such as population density. The proposed methodology allows integrating other exogenous variables that might be interesting to policy makers. For instance, a tourism index could be included in the assessment to evaluate whether tourism impacts on the efficiency of municipalities in the provision of municipal solid waste services and therefore, to analyze the implementation of an eco-tax for tourists.

Wooden sticks for plaque streaking and microbiological inoculation might be more cost- effective, but is its large scale use feasible? Quality control methods and proof of concept / Métodos de controle de qualidade e prova de conceito para a utilização de palitos de madeira em microbiologia podem ser mais econômicas, mas seu uso em larga escala é viável? Método de controle de qualidade e prova de conceito

The loop is a material classically used in the laboratory for the purpose of plate streaking and handling biological materials. However, metal loops techniques might be time consuming, considering the amount of time spent to guarantee its cooling process through each inoculation. Furthermore, plastic loops may also represent environmental issues during its production and discard process and can also represent higher costs for the laboratory. Thus, in situations of limited resources, even the simplest materials can be restricted due to logistical and budgetary issues, especially in developing countries. Inspired by demands like these, facing an occasional shortage of supply of laboratory plastic handles, we hereby present a quality control for sterilization methods and cost-effectiveness studies towards the use of wooden sticks in a Latin American country and we discuss the possibility of the large-scale use of this technique.

A alça calibrada é um material usado classicamente em laboratório para fins de inoculação em placas e manuseio de materiais biológicos. No entanto, as técnicas de alças metálicas podem consumir muito tempo, considerando a quantidade de tempo gasto para garantir seu processo de resfriamento a cada inoculação. Além disso, alças de plástico também podem representar questões ambientais durante o processo de produção e descarte e também podem representar custos mais altos para o laboratório. Assim, em situações de recursos limitados, até os materiais mais simples podem ser restringidos devido a questões logísticas e orçamentárias, especialmente nos países em desenvolvimento. Inspirados por demandas como essas, diante de uma escassez ocasional de suprimentos de alças de plástico de laboratório, apresentamos um controle de qualidade para métodos de esterilização e estudos de custo-efetividade para o uso de varas de madeira em um país latino-americano e discutimos a possibilidade de grande uso em escala dessa técnica.

Variables Influencing per Capita Production, Separate Collection, and Costs of Municipal Solid Waste in the Apulia Region (Italy): An Experience of Deep Learning.

Municipal solid waste (MSW) must be managed to reduce its impact on environmental matrices and population health as much as possible. In particular, the variables that influence the production, separate waste collection, and costs of MSW must be understood. Although many studies have shown that such factors are specific to an area, the awareness of these factors has created opportunities to implement operations to enable more effective and efficient MSW management services, and to specifically respond to the variables that have the most impact. The deep learning approaches used in this study are effective in achieving this goal and can be used in any other territorial context to ensure that the organizations that deal with these issues are more aware and create useful plans to promote the circular economy. Our findings indicate the important influence of number of rooms in a residential buildings and construction years on MSW production, the combination of services such as municipal collection centers and door-to-door service for separate MSW collection and the characteristics of the residential buildings in the municipalities on MSW management costs.

Plant Secondary Metabolites: An Opportunity for Circular Economy.

Moving toward a more sustainable development, a pivotal role is played by circular economy and a smarter waste management. Industrial wastes from plants offer a wide spectrum of possibilities for their valorization, still being enriched in high added-value molecules, such as secondary metabolites (SMs). The current review provides an overview of the most common SM classes (chemical structures, classification, biological activities) present in different plant waste/by-products and their potential use in various fields. A bibliographic survey was carried out, taking into account 99 research articles (from 2006 to 2020), summarizing all the information about waste type, its plant source, industrial sector of provenience, contained SMs, reported bioactivities, and proposals for its valorization. This survey highlighted that a great deal of the current publications are focused on the exploitation of plant wastes in human healthcare and food (including cosmetic, pharmaceutical, nutraceutical and food additives). However, as summarized in this review, plant SMs also possess an enormous potential for further uses. Accordingly, an increasing number of investigations on neglected plant matrices and their use in areas such as veterinary science or agriculture are expected, considering also the need to implement "greener" practices in the latter sector.

Bioeconomy - present status and future needs of industrial value chains.

The necessary reduction of greenhouse gas emissions requires a comprehensive shift from fossil to renewable raw materials. This is accompanied by a fundamental reorganization of the value chains of the energy sectors and large parts of the manufacturing industry. In the long term, bio-based industrial raw materials will be processed preferentially by the chemical industry. In order to use the raw materials as fully as possible, sectors that support cascade use and the recycling of by-products and products after use will gain in importance. These are in particular the waste management and energy sectors, which will be integrated into the circular value chains of the bioeconomy. The industrial realization of these value chains depends essentially on the legal framework conditions, which must be developed further accordingly.

Effects of operating conditions on biogas production in an anaerobic digestion system of the food and beverage industry.

BACKGROUND: Food residuals (FR) were anaerobically biotransformed to produce biogases (e.g. methane and hydrogen), and different pre-treatment conditions, including particle size, oil content, pH and salt content, were controlled in this study. The bio-solids of a municipal solid waste (MSW) from a wastewater treatment plant were added to assess its effect on anaerobic transformation efficiency and gas yields. RESULTS: The breaking of FR and the application of MSW were effective in enhancing the transformation efficiency and yield of biogases. The energy transfer efficiency value of the combined FRs used in this study was probably 23%. However, it can be very cost effective to apply arbitrary proportions to treat two types of FR in the anaerobic digestion tank of a wastewater treatment plant. It was also found that the alkalinity and pH value were two major parameters that controlled the success of the transformation. About 0.16-0.17 kg of alkalinity was needed during the anaerobic digestion of 1 kg dry FR, but this requirement was decreased by the treatment applying MSW. Olive oil had higher reducing rates when used as a substitute for heat-oxidized oil to study the effect of oil content on methylation. CONCLUSION: The conditions for anaerobic digestion established in this study were practical for the digestion of FR in wastewater treatment plants in Taiwan. However, we nonetheless found that it was cost effective to use arbitrary proportions for both types of FR and integrate the anaerobic digestion process used in wastewater treatment plants. © 2020 Society of Chemical Industry.

Towards a bio-based circular economy in organic waste management and wastewater treatment - The Polish perspective.

Bio-based solutions are expected to ensure technological circularity in priority areas such as agriculture, biotechnology, ecology, green industry or energy. Although Poland, unlike the other EU member states, has not yet adopted a precise political strategy to promote bioeconomy, it has taken several actions to enable smart, sustainable and inclusive growth. This goal can be achieved by developing selected bioeconomy-related areas such as the biogas industry together with novel technologies implemented to optimize treatment of municipal sewage and management of organic solid waste. Here, the relatively strong status of the Polish biogas sector is presented. The widely used practice of sewage sludge biomethanation has led to construction of numerous complex installations combining biological wastewater treatment plants with anaerobic digesters. Based on physico-chemical processing of biostabilized sludges, a novel method for efficient granulated soil fertilizer production is elaborated, in line with the concept of circular economy and the notion of "waste-to-product". It is also shown that anaerobic fermentation of sewage sludges can be optimized by co-digestion with properly selected co-substrates to increase bioprocess yield and improve the resultant digestate fertilizer quality. The problem of post-fermentation eutrophic sludge liquors, environmentally hazardous waste effluents requiring proper treatment prior to discharge or field application, is addressed. Attempts to optimize biological treatment of digestate liquors with complex microbial consortia are presented. The Polish innovations described show that the "zero waste" path in circular bioeconomy may bring advantageous results in terms of transformation of waste materials into commercial, added-value products together with recovery of water resources.

[Reducing medication waste; a challenge for care providers and society]. / Geneesmiddelverspilling verminderen.

Annually, in the Netherlands, at least 100 million euro is wasted on unused medication. This waste not only has considerable economic implications, but is also associated with an unnecessary burden on the environment and suboptimal care due to nonadherence to therapy. The reasons for medication wastage can be found throughout the entire pharmaceutical supply and use chain, which includes manufacturers, distributors/wholesalers, prescribers, pharmacists and patients, both in the community and hospital setting. A number of strategies are needed to minimize the waste of medication, one of which should be a preventative approach. Involvement of all stakeholders in the supply chain is a prerequisite for a successful outcome. It is important that prescribers are aware of the extent and consequences of wastage, and of the possible ways to reduce it.

Sustainable financing for municipal solid waste management in Nepal.

Financing municipal solid waste (MSW) services is one of the key challenges faced by cities in developing countries. This study used plastic waste, a constituent of MSW, to explore the possibility of generating revenue for financing MSW management in the municipalities of Nepal. The results of this study suggest that plastic material recovery could generate revenue, which is equivalent to 1.38 times of the plastic-waste-related management cost when collection efficiency reaches 66.7%. An increase in 1% of recovery rate and collection efficiency could cover an additional 4.64% and 2.06% of the costs of managing plastic waste, respectively. In addition, an increase in tax on imported plastic materials could also motivate recovery of plastic waste for recycle and reuse. An additional 1% tax on plastic imports would be sufficient to cover plastic-related waste management when plastic waste recovery and collection efficiency rates are low. This plastic recovery- revenue exercise could be expanded to other materials such as paper and metal to fully understand the possibility of sustainable financing of MSW management and reducing environmental harm in developing countries like Nepal.

Medical waste management - how industry can help us to protect environment and money?

Background: The global climate change and its consequences force us to remodel our processes and rethink the current model of providing the HD treatments. Waste management have a massive impact on the environment and the economy. Every HD session produces above 1 kg of medical waste, which should be properly stored and destroyed. In particular in the pandemia time we should improve the dialysis unit budget as well as decrease CO2 emission produced during the waste elimination.Materials and Methods: The checked the weight of different dialyzers used regularly in dialysis centers in Poland. The Kern CM 320-IN scale was used for the measurement. The measurement accuracy was 0.1 g. Also the filling volume of each dialyzer has been taken into consideration.Results: The dialyzers were divided into four groups depending on the surface. 1,4m2 in group one, 1.5-1.6 m2 in group two, 1.7-1.8 m2 in group three and finally 2.0-2.2 m2 in group four. FX class dialyzers were lightest in every group. The heaviest ones were Polyflux dialyzers. The difference between the lightest and heaviest dialyzers was about 95 g. The filling volume was lowest in FX dialyzers and the highest in Elisio dialyzers. The difference was 20 mL.Conclusions: The weight of different dialyzers available on the market differs. The decision-makers should take into account this fact as the additional quality feature. In extreme cases the weight difference reaches 95 g. In yearly perspective, the usage of the lighter dialysis set can cause the 17 million kg decrease of medical waste and significant savings.

Incentive Mechanism and Subsidy Design for Construction and Demolition Waste Recycling under Information Asymmetry with Reciprocal Behaviors.

To solve information asymmetry, we adopted the principal-agent framework to design the incentive mechanisms between the remanufacturer and the collector in the construction and demolition (C&D) waste-recycling industry. By using the model of reciprocity, we analyzed how the entities' behavioral motives affect their decisions in terms of the incentive mechanisms. The findings showed that the collector responds to their perception of the remanufacturer's intentions. If the perception is positive, they will make more effort in the collection work. If not, less effort will be put forth. Most importantly, we found that reciprocity helps to save the remanufacturer cost in the incentive mechanisms and makes the collector choose a higher effort level in the collection work. This finding showed that reciprocity serves to solve information asymmetry. By conducting a numerical simulation, we found that although a high subsidy policy can achieve rapid improvement of recycling-supply-chain performance, it is inefficient in maintaining friendly cooperation between the remanufacturer and the collector.

Utilization of Fish Waste as Fish Feed Material as an Alternative Effort to Reduce and Use Waste.

BACKGROUND AND OBJECTIVE: Waste of fish catching and waste of fish fillet processing will cause environmental pollution, but these materials can still be used as raw material for fish feed. The objective of this research was to change fish wastes to be made as fish powder as raw material of fish feed. MATERIALS AND METHODS: This research employed a completely randomized design with three treatments; Treatment A is artificial feed that uses raw material from trash fish, Treatment B is artificial feed that uses raw material from fish fillet waste and as control is factory-made feed. The silver pompano fish stocking was done with stocking density of 20 fishes m-3. The fishes were cultured for 60 days and they were adapted with formulated feed during 7 days before testing. RESULTS: Fish powder material in Treatment A coming from trash fish waste had good enough protein content by 43.84%, while fish powder material in Treatment B coming from fish fillet waste had lower protein content by 36.3%. The results showed that the control produced better growth activity indicators compared to Treatment A and B. The results of economic analysis showed that Treatment A and B were cheaper to produce compared to control. CONCLUSION: Fisheries waste both fish catch and fish fillet waste can be used as raw material for making silver pompano fish feed. Utilization of the two wastes has two functions namely saving on aquaculture costs and reducing fisheries waste.

A Chance-Constrained Vehicle Routing Problem for Wet Waste Collection and Transportation Considering Carbon Emissions.

In order to solve the optimization problem of wet waste collection and transportation in Chinese cities, this paper constructs a chance-constrained low-carbon vehicle routing problem (CCLCVRP) model in waste management system and applies certain algorithms to solve the model. Considering the environmental protection point of view, the CCLCVRP model combines carbon emission costs with traditional waste management costs under the scenario of application of smart bins. Taking into the uncertainty of the waste generation rate, chance-constrained programming is applied to transform the uncertain model to a certain one. The initial optimal solution of this model is obtained by a proposed hybrid algorithm, that is, particle swarm optimization (PSO); and then the further optimized solution is obtained by simulated annealing (SA) algorithm, due to its global optimization capability. The effectiveness of PSOSA algorithm is verified by the classic database in a capacitated vehicle routing problem (CVRP). What's more, a case of waste collection and transportation is applied in the model for acquiring reliable conclusions, and the application of the model is tested by setting different waste fill levels (WFLs) and credibility levels. The results show that total costs rise with the increase of credibility level reflecting dispatcher's risk preference; the WFL value range between 0.65 and 0.75 can obtain the optimal solution under different credibility levels. Finally, according to these results, some constructive proposals are propounded for the government and the logistics organization dealing with waste collection and transportation.

Optimization of municipal solid waste collection and transportation routes, through linear programming and geographic information system: a case study from Sanliurfa, Turkey.

Solid waste is one of the important causes of the environmental crisis that negatively impacts human health throughout the world and is fast approaching a disaster level that will pose a direct threat to human life. As with all other environmental problems, the increase in solid waste production that goes hand in hand with growing population and rising consumption has become a focus of great concern. Along with these rising levels, the investment, management and maintenance of solid waste collection and transport vehicles is seeing a continual increase in financial outlay. It is clear from the budgets of local authority solid waste management systems, 65 to 80% of which are accounted for by domestic waste, that the collection and transport of solid waste is a high-cost process and that this expenditure can be significantly reduced by the reorganisation of solid waste collection routing schedules and the minimization of collection frequency. This study demonstrates a linear programming model in order to develop an optimal routing schedule for solid waste collection and transportation, thereby reducing costs to a minimum. The neighbourhood of Veysel Karani in the Haliliye District of Sanliurfa Province, Turkey, was specifically selected for this case study, having the suitable socio-economic and demographic variables to be representative of a metropolitan urban area. Firstly, the data regarding the municipal solid waste collection and transport routes were obtained from the local authority. Analysis and verification of these data were then performed. With the field study, these data were verified on-site, and the missing data were completed. Linear programming and geographic information system (GIS) analysis were used to determine the best route. Consequently, it is concluded that it is possible to save the route by 28% with GIS analysis and 33% with linear programming analysis according to the existing municipal solid waste collection and transportation routes.

Influencing factors behind inappropriate solid waste management of small clinics in a resource-constrained country.

Appropriate clinical waste management is a critical concern in today's era. Resource-constrained countries agonize greatly over this issue in order to mitigate inappropriate clinical waste management practices. The goal of this study is to assess factors behind inappropriate waste management of small clinics in resource-constrained countries. We tested the hypothesis that negligence of government, knowledge and awareness, and financial burden are three key factors behind inappropriate solid waste management of small clinics. A two-phase survey including a pilot study and a main study was conducted for exploratory factor analysis and confirmatory factor analysis, respectively, in the fourth largest city of Pakistan, i.e., Hyderabad. One sample t test was used to validate the hypothesis, the correlation between the three key factors, and the location of the clinics were established. These factors were found to have a contribution to inappropriate waste management of small clinics. The hypothesis was then validated, and all three factors were found to have no significant variation in responses with the contrast of three types of clinic locations, namely, low-, medium-, and high-income areas. Responses were almost identical and bear equal significance from all locations, the financial burden factor is at the highest, the second factor is the negligence of government, and the third factor is that of knowledge and awareness. This study highlights the factors that are usually neglected and can help to improve solid waste management of small clinics in resource-constrained countries.

Pricing Strategy of Construction and Demolition Waste Considering Retailer Fairness Concerns under a Governmental Regulation Environment.

In order to investigate the issues of the recycling and remanufacturing of construction and demolition waste (C&D waste), this paper develops a closed-loop supply chain (CLSC) consisting of a manufacturer, a retailer, and a recycler, considering both the retailer's fairness concern psychology and governmental regulations. Four mathematical models are developed for the calculations, and the models are solved through game theory. In both the decentralized and centralized scenarios, the members' strategies are discussed and the optimal values of decision variables are determined. A numerical study is carried out for sensitivity analyses to verify the accuracy of the theoretical conclusions. The results reveal that retailer fairness concerns lead to a decrease in the wholesale price of building materials and negatively affect manufacturers' profits. Additionally, governmental regulations can effectively increase the recycling amount and improve the utilization rate of C&D waste, and promote a virtuous cycle of the recycling and remanufacturing of C&D waste.

Environmental impact and economic sustainability analysis of a novel anaerobic digestion waste-to-energy pilot plant in Pakistan.

A novel medium-large industrial-scale, anaerobic digestion (AD) waste-to-energy pilot plant has been investigated in terms of cost-benefit, environmental impact, and economic sustainability. This pilot plant exclusively features a multi-digester AD system induced by motorized stirring, methane purification, compression, storage and digestate-fertilizer processing systems, and subsequent electricity generation. The operational productivity and success of the pilot plant has been proven on a variety of waste feedstock substrates in the form of cow-buffalo manure and potato waste. The plant has an average energy productivity of 384 kWh/day and an annual rate of return was estimated to be 15.4%. The life cycle environmental impact analysis deliberated the significant impact potentials in terms of climate change (kg CO2 equivalent), and fossil depletion (kg of oil equivalent) for three selected substrates: 100% cow-buffalo manure (CBM), 100% potato waste (PW), and a mixture of 75% CBM and 25% PW. The results show the climate change potential of 70 kg, 71 kg, and 149 kg and fossil depletion potential of - 2.43 kg, - 16.45 kg, and 18 kg per 2000 kg of substrate slurry, respectively. As such, the substrate of 100% CBM posed the least climate change impacts whereas 100% PW has been established most effective under the fossil depletion category.