Economic Concepts Research Articles

A mathematical programming model integrating waste pickers in urban area recycling practice

Urbanization has resulted in a significant accumulation of waste in densely populated areas. Effective household waste separation practices within urban areas are crucial for advancing the concept of circular economy. The informal system has contributed remarkably to urban material circulation, but it has not been appropriately valued. Through the partnership among the municipal solid waste authorities, condominium building residents, and waste pickers, the latter can be engaged in the community to assist in household waste separation. This initiative would not only enhance their income and reduce probable occupational risks but also augment the recycling rate in the community. Based on the insights from the current waste picker assignment policy in Taichung City, this study has established a mathematical programming model by considering the overall waste separation volume and proximal distance to the neighborhood, facilitating the assignment of individual waste picker to multiple communities within the neighborhood area. Consequently, concerned waste pickers may increase their income and avoid the constraints of picking up recyclables in high-occupational-risk areas. Additionally, it may reduce the volume of unsorted garbage in the community. According to the findings of case studies, the developed model could obtain an optimal solution or acceptable approximate solution in a short timeframe. In contrast to the outcomes from the existing waste picker assignment policy, the application of the developed model could increase the total volume of sorted recyclables, which was directly proportional to the income of waste pickers, by 2.3–2.6 times.

THE RELATIONSHIP BETWEEN THE CIRCULAR ECONOMY AND BUSINESS PERFORMANCE: A SYSTEMATIC LITERATURE REVIEW

The circular economy represents an effective way to address limited resources and mitigate the impact of human activity on the planet. To summarize the possible effect of circular economy implementation on business performance and its possible measurement, a systematic literature review on a final sample of 28 papers was conducted. The main findings reveal that the circular economy can help to improve business performance and that numerous indicators could be used to measure it, especially the balanced scorecard approach, which seems suitable for such classification (however, more research on this topic is needed). Additionally, it was revealed that the circular economy concept itself has no clear and generally used definition, which complicates the summarizing of the revealed indicators. To simplify future research, we proposed a research framework based on this systematic literature review and emphasized the research gaps.

Agglomeration Economies and Rural-to-Urban Migration in India

<p style="text-align:justify"><span style="font-family:Times New Roman,Times,serif"><span style="font-size:16px"><span dir="ltr" lang="EN-US"><span style="color:black">Keeping in view the concept of agglomeration economies and the New Economic Geography (NEG) angle, this paper makes an attempt to examine the rural to urban population movement at the district level in India. The findings do not favour a strong positive association between levels of urbanization and migration rates.  However, there exists a cluster of districts which are able to attract migrants on a large scale in spite of being already urbanized. The work participation rate, share of services and construction work, and literacy rate all form parts of this positive nexus, indicating that opportunities exist with increased levels of urbanization which in turn prompt people to migrate. The positive spill-over effects of higher levels of urbanization are not limited to the urban spaces only as the adjoining rural areas also seem to have undergone   a significant transformation. The land use pattern and activities are changing and some of the developmental impact is evident. However, the regional variations in this respect are evident. There are sharp differences in the relationship between urbanization level and migration rates across regions. The nature of urbanization and its determinants and the outcome variables of urbanization and migration also unravel regional variations. Besides, there are many districts with higher levels of urbanization; yet, they are not able to attract migrants at a rapid pace. New investment opportunities can be created in these spaces to reduce the cost of growth and make employment generation process more effective, facilitating the rural population to take the benefits of agglomeration economies.</span></span></span></span></p>

From by-products to new application opportunities: the enhancement of the leaves deriving from the fruit plants for new potential healthy products.

In the last decades, the world population and demand for any kind of product have grown exponentially. The rhythm of production to satisfy the request of the population has become unsustainable and the concept of the linear economy, introduced after the Industrial Revolution, has been replaced by a new economic approach, the circular economy. In this new economic model, the concept of "the end of life" is substituted by the concept of restoration, providing a new life to many industrial wastes. Leaves are a by-product of several agricultural cultivations. In recent years, the scientific interest regarding leaf biochemical composition grew, recording that plant leaves may be considered an alternative source of bioactive substances. Plant leaves' main bioactive compounds are similar to those in fruits, i.e., phenolic acids and esters, flavonols, anthocyanins, and procyanidins. Bioactive compounds can positively influence human health; in fact, it is no coincidence that the leaves were used by our ancestors as a natural remedy for various pathological conditions. Therefore, leaves can be exploited to manufacture many products in food (e.g., being incorporated in food formulations as natural antioxidants, or used to create edible coatings or films for food packaging), cosmetic and pharmaceutical industries (e.g., promising ingredients in anti-aging cosmetics such as oils, serums, dermatological creams, bath gels, and other products). This review focuses on the leaves' main bioactive compounds and their beneficial health effects, indicating their applications until today to enhance them as a harvesting by-product and highlight their possible reuse for new potential healthy products.

Sustainability Evaluation of a Paper and Pulp Industrial Waste Incorporation in Bituminous Pavements

The valorization of wastes as an alternative or secondary raw material in various products and processes has been a solution for the implementation of sustainability, a safer environment, and the concept of circular economy in the efficient use and management of natural resources. To promote sustainability through a circular economy approach, this work tries to demonstrate the environmental gains that are obtained by bringing together, in an industrial symbiosis action, two large industrial sectors (the pulp and paper and the road pavement sectors) responsible for generating large amounts of wastes. A sustainability assessment, based on a life cycle and circular economy approach, is presented here, and discussed using a simple case study carried out on a real scale. Two wastes (dregs and grits) from the pulp and paper industry (PPI) were used to partially replace natural fine aggregates in the production of bituminous mixtures used on the top surface of road pavements. The impacts at a technical, environmental, economic, and social level were assessed and it was shown that this simple waste valorization action is not only positive for the final product from a technical point of view, but also for the environment, causing positive impacts on the different sustainability dimensions that were evaluated.

More Biosurfactants and Fewer Synthetic Surfactants to Improve Alkali-Surfactant-Polymer Flooding: Feasibility Study and Large-Scale Field Application

Summary Alkali-surfactant-polymer (ASP) flooding has achieved highly enhanced oil recovery (EOR) in the Daqing Oil Field; however, there are concerns about synthetic surfactants owing to their high cost and difficulty in biodegradation. Cheap biosurfactants conform to human concepts of green circular economy; however, known biosurfactants, as well as their mixtures with alkali, cannot reduce water/oil interfacial tension (IFT) to ultralow values below 0.01 mN/m, which is necessary for ASP flooding to effectively mobilize residual oil. Therefore, we investigate the feasibility of partially replacing synthetic surfactants with biosurfactants rather than completely replacing them to improve ASP flooding. First, through a series of IFT tests, a blend of rhamnolipids (RLs) and alkylbenzene sulfonate (ABS) in a 1:1 mass ratio is determined to be the optimal mixed surfactant and labeled RL/ABS-opt. Second, the interfacial activities, phase behaviors, and wettability alteration capabilities of ASP solutions with RL/ABS-opt are studied. Then, 1.0 wt% NaOH and 0.2 wt% RL/ABS-opt are determined to construct a new ASP system. Subsequently, the waterflooded cores are displaced using the new and the classical ASP systems. Based on the promising experimental results, the new ASP system floods a test block of 56 wells for 3 years. The EOR and surfactant costs are calculated to determine the technical and economic effects. Finally, the concentrations of surfactants before and after activated sludge treatment (AST) are tested by spectrophotometry to verify the biodegradability of RLs better than that of ABS. The laboratory and field results indicate that more biosurfactants and fewer synthetic surfactants could improve ASP flooding to be more environmentally friendly and cost-effective with a higher EOR.

Circular Economy as an Important Lever to Reduce Greenhouse Gas Emissions: Case of an Electricity Distribution Company in Morocco

This article discusses the major challenges related to greenhouse gas (GHG) emissions in the electricity sector and their impact on global climate change. The electricity sector is responsible for about a quarter of total global GHG emissions. To address these challenges, Life Cycle Assessment (LCA) is used to measure the environmental impact of different energy sources and electricity generation and distribution processes. The circular economy is presented as a promising approach to reducing the carbon footprint of the electricity sector. By optimizing the use and value of materials throughout their life cycle, this approach contributes to waste minimization and resource efficiency. Morocco is committed to reducing its GHG emissions and has adopted policies and regulatory frameworks to combat climate change. This study aims to calculate the climate change impacts of electricity distribution phases by applying a life-cycle approach to the case of an electricity distribution company in Morocco. This assessment makes it possible to identify significant contributors from each area. In the context of this company, it is a question of demonstrating how the application of the principles of the circular economy concepts contributes to the reduction of greenhouse gas emissions, in particular, that of scope 3. This study may be useful for other similar companies.

Utilizing waste rocks from phosphate mining in Jordan as concrete aggregates

This study investigates the potential of replacing natural aggregates in concrete with aggregates obtained from Phosphate Mine Waste (PMW) rocks in Jordan. Several tests were conducted to determine the PMW rocks' chemical, physical, and mechanical properties according to ASTM standards. A comprehensive experimental investigation was conducted, involving thirty-six concrete cylinder specimens, to evaluate the strength and durability properties of concrete made with PMW rocks compared to concrete made with natural limestone aggregates. The tested aggregates of PMW rocks consist mainly of quartz, dolomite, montmorillonite, and fluorapatite. Their physical and mechanical properties were found to be similar to the natural aggregates used for concrete. Concrete specimens made of waste rocks had an average compressive strength of 28.72 MPa at 28 days versus 30.18 MPa for concrete specimens made with natural aggregates. The tensile splitting strengths of the concrete made with PMW aggregates were higher than expected, with an average of 5.36 MPa at 28 days, whereas the reference specimens had an average tensile splitting strength of 5.49 MPa at 28 days. According to the findings, PMW rocks can successfully replace natural aggregates in structural and infrastructural constructions, enhancing the circular economy concept and contributing to a more environmentally friendly mining industry.

“Minorities”, the nation and Europe in the history textbooks of Germany, Spain and Turkey

A feature of the concept of “minorities” is the invisibility and stigmatization of communities, more so within the idea of the nation. The European Union project stimulated new vistas, and offers challenges to reconcile peoples under a new political, social and economic concept. However, in the midst of crisis and war in Europe, mistrust and hostility are increasing, incited by right-wing populism and nationalism and these aims of the last century are slowly making their way into history textbooks. This article analyses the representation and construction of these complex concepts in eight German, Turkish and Spanish secondary school history textbooks. In times of strengthening nationalism, it is also discussed here whether the representations convey essentialist ideas and imperialistic structures hidden between the lines in school textbooks, or whether they reflect the concept of “minorities” as a component of a pluralistic and hybrid European society. The research is divided into two areas: 1) A quantitative analysis of textbooks: A comparative research will be carried out on the representation of 'minorities' in English, German, Turkish and Spanish history textbooks. The textbook research is temporally limited to the period from the sixteenth until the twenty-first centuries.

How Does a Decision-Making Tool Enhance Spent Mushroom Substrate Valorization into Polysaccharides?

In mushroom farming, one kilogram harvested results in about five kilograms of spent mushroom substrate (SMS), posing an environmental management challenge. As an in-tune work with the concepts of circular economy, cleaner production, and waste minimization, this study has developed a mathematical model than analyzes the valorization potential of SMS through polysaccharide production. The in-depth mathematical model is based on a system dynamics approach, which explains the interactive interplay amongst the production process, related costs, energy consumption, and caused emissions. The model has been developed in a generic way. Meaning that it can be re-adjusted flexibly for a different cleaner production process. A user-friendly interface has been developed. Users can easily maneuver around the variables within the model that offers instantaneous insight into the environmental and economic impacts of SMS valorization. This interface was later integrated into an educational context to serve as an interactive decision-making tool for cleaner production modelling. The main purpose of the developed tool was to favor understanding of causalities between production chains, energy consumption, labor, emissions, and expenses. This tool has been tested on master’s degree students in a cleaner production course. Survey results show that 82% of students report the need to incorporate similar decision-making tools in their learning curriculum. In sum, the application of system dynamics to the valorization of SMS does not only present an attractive solution for this environmental problem but also shows great potential in setting educational backgrounds for an interactive and close-to-life learning process. It is recommended to develop more interactive tools available for students.

A multi-objective fuzzy mathematical model for circular economy with leasing as a strategy

PurposeThis paper aims at developing a multi-objective mathematical model of circular economy that integrates key concept of leasing as a strategy in addition to reuse, refurbishing, primary recycling, secondary recycling and disposal.Design/methodology/approachThis paper proposes multi-objective fuzzy mixed integer linear programming mathematical model considering multi-product, multi-echelon and multi-capacitated concepts of the circular economy. The three objectives of the proposed model, namely, economic, environmental and social are solved simultaneously using constraint approach to obtain balanced trade-off between the objective functions. The model is validated by solving a case study from the literature. The proposed model is made pragmatic for industrial application by considering multi-external suppliers multi-customer zones, multi-disassembly centers, multi-collection centers and multi-refurbishing centers and accounting for purchasing, processing, transportation, set-up costs and capacity constraints at the same time.FindingsThe results show that the leasing of the products improves the economic function in addition to the known environmental improvements. The proposed model also shows that the circular economy can generate the jobs for the unskilled people at different locations.Research limitations/implicationsThe proposed model can be further improved by considering the non-linearity due to economy of scale at various centers and in transportation. The model can be further extended to make it multi-period model.Practical implicationsThe proposed model of circular economy can be used by the organizations as a policy tool to decide the optimum number of collection centers, disassembly centers, refurbishing centers, recycling centers and disposal centers and their optimum locations and allocations. The organizations can also trade-off among economic, environmental and social benefits of their proposed decisions in circular economy.Originality/valueThe originality of the proposed mathematical model is consideration of leasing as a strategy to have better control over the supply chain for circularity; considering the training of unskilled people for backward supply chain jobs and accounting for primary recycling and secondary recycling separately for economical computation.

Transparent wood-based materials: A new step toward sustainability and circularity

Wood is a natural composite material mainly consisting of three components, i.e., cellulose, hemicellulose, and lignin. It exhibits a complex hierarchical structure characterized by open channels, aligned in the growth direction, having specific porosity at micro-, meso-, and macro-scale, and an extended opacity, due to adsorption phenomena because of the presence of lignin and scattering, as different refractive indexes characterize its components. Even if during the historical ages some of its applications have been replaced by other materials, wood still covers a large part of common uses, which range from biomass for energy recovery to material for the building sector, or from artifacts to household/furniture manufacturing. Despite its real invention dating to 1992, only about ten years ago two independent research groups, one from the University of Maryland (USA) and the other from the Royal Institute of Technology (Sweden) rediscovered and started to thoroughly investigate the so-called transparent wood (TW). TW can be derived from almost any wood biomass through specific chemical treatments focused on lignin. These aim to completely remove this component from wood or to eliminate the chromophore groups present in the pristine material, hence obtaining, after direct densification or after infiltration with a suitable polymer resin, a new material with very high transparency, toughness, and lightness. These characteristics can further be combined with other specific features (such as environmental protection, flame retardancy, photoluminescence, and energy storage ability, among others), which open the way toward the development of new, up-to-date, advanced, and sustainable materials for both structural and functional purposes, fulfilling the current concepts of circular economy and sustainability. The present review is aimed at providing the reader with an overview of the characteristics of transparent wood, describing the latest applications and, finally, discussing some challenging issues and perspectives for possible developments in the forthcoming years.

Meeting Report: Microbes as Safeguards of the Environment

Abstract From 12 to 14 March, a gathering of microbiologists and biotechnologists convened at the International University of Andalucía (UNIA) in Baeza (Jaén, Spain) under the auspices of UNIA and the Applied Microbiology International (AMI) Society. The primary objective of this meeting was to analyse the pivotal role microbes play in sustaining our planet in a broader context—both from the descriptive (what is the state of affairs) and the prescriptive perspective (what to do and look for regarding activities of interest). The workshop focused on exploring the ecological aspects of microbes in soil and water, including some extreme environments, the potential of microorganisms as promoters of plant growth and biocontrol agents as well as active large-scale catalysts for environmental health. Various topics were examined in this context, encompassing the application of microbes as platforms for the biosynthesis of value-added chemicals, bioremediation technologies, the concept of the circular economy, the emergence of zoonotic concerns within a dynamically changing global environment and the role of microbes in precision nutrition and precision medicine. In alignment with the strategic plan of AMI, the discussion was focused on the background of the United Nations Sustainability Development Goals (UN SDGs). These targets were formulated at the beginning of the past decade to guide humanity towards a sustainable future. The UN SDGs aim to prevent the overstepping of planetary boundaries, which are endangering Earth's biodiversity and even human survival.

Valorization of agitated thin film dryer (ATFD)-mixed-salt from textile wastewater for its application in leather manufacturing – a sustainable approach

ABSTRACT The textile industry uses sodium chloride and sodium sulphate during the dyeing process to improve the fixation of dyes on fabrics. After wastewater treatment, the reject stream is dried resulting in mixed salts as solid wastes that are not reused. The leather industry also uses a vast quantity of salt for temporary preservation of skins/hides and as swelling-suppressing agent during the pickling (acidification) process. Thus, an attempt was made to utilize the mixed salt obtained from the textile industry to replace sodium chloride in leather processing. It was found that a 40% w/w offer of ATFD salt was able to preserve the skins for 3 months, which was on par with the preservation carried out using a similar quantity of sodium chloride in conventional preservation process. Likewise, for the pickling process, an offer of 10% w/w ATFD salt provided sufficient deswelling action when compared to conventionally used sodium chloride. However, the residual colour of the mixed salts affected the quality of the leather obtained. To overcome this, an electro-oxidation treatment was carried out to obtain decolourized salts. The COD measurements showed that the 1% solution of ATFD-3 salt reduced from 471 ± 25 to 88 ± 16 ppm. A similar trend was also seen in BOD reduction from 80 ± 12 to 18 ± 10 ppm. These results confirmed that the colour removal could be due to the degradation of the organic contaminants present in the ATFD salt. Thus, the treated ATFD salt can be reused for leather processing without affecting leather quality, thus promoting the concept of circular economy.

What is the meaning of value in a circular economy? A conceptual framework

Today, the concept of a circular economy (CE) has become omnipresent. Central to this concept is the term value, however, it is not properly defined, which leads to different interpretations, and hinders implementation of the CE concept. Hence, this article operationalizes the theoretical concept of value into a more practical understanding. First, the meaning of value within the CE context is examined, followed by the development of a framework wherein value is decomposed into two essential types; functional and created value. Next, the framework is applied to an illustrative case study involving four different end-of-life strategies: landfilling, closed loop recycling, remanufacturing and reusing. The framework enables a holistic comparison of the different strategies, represented in a visually compelling way, and clarifies the connection between theoretical CE concepts and practical measures. Consequently, it enhances the understanding of existing CE indicators and serves as a stepstone for the development of new indicators.

Critical Review of Islamic Economic Thoughts Based on the Perspective of Three Schools (Mazhab): Iqtishaduna, Mainstream, and Alternative-critical

Islamic economics is a science that combines economics with the principles of Shariah. The development of Islamic thought and economics started from the time of Rasulullah SAW, Sahabat until today. Regarding how the concept of Islamic economics is, three mazhabs have different views, namely: Iqtisaduna Mazhab, mainstream mazhabs, and critical alternative mazhabs. This article aims to understand the views of Islamic economics in all the three mazhabs mentioned above. The three mazhabs have different backgrounds in criticizing the concepts of socialist and capitalist economics. The Iqtishaduna mazhab was pioneered by Baqir al-Sadr, this mazhab chose to replace the economic term with ‘iqtishaduna’. Mainstream mazhabs approach Western economic thought with an open heart and mind, not necessarily rejecting it completely; therefore, there needs to be filtering and refinement of economic concepts; while the alternative-critical mazhab is a spirit of criticism that invitesnot only socialists and capitalists who are are criticized, but also Islamic economic thought should be criticized, because this mazhab argues that Islam must be true, but Islamic economics is not necessarily true. Keywords: Islamic economics, Iqtishaduna, mainstream, alternative-critical

Circular And Sustainable: Evaluating Lithium-Ion Battery Recycling using a Combined Statistical Entropy and Life Cycle Assessment Methodology.

While there has been a growing interest on the concept of Circular Economy (CE), its correlation with sustainability remains controversial. In this work, the combination of Statistical Entropy Analysis (SEA) and Life Cycle Assessment (LCA) is proposed as a new methodology to evaluate recycling processes from the perspective of materials circularity and environmental impacts using a Li-ion battery recycling process as a case study. This work addresses the need of quantitative circularity indicators, as SEA evaluates the concentration of materials at a systems level, while LCA measures the environmental impact of recycling processes in comparison with virgin raw materials production. It was found that process optimization points can be found by simultaneously accounting for materials recovery and the LCA categories of global warming potential, ozone depletion and mineral resource scarcity. Furthermore, a strong correlation was found for the first time between the recovery of critical elements and the environmental impact of raw materials production. The proposed methodology thus offers a robust analysis of a product lifecycle that aids in its design and optimization from the CE perspective.

Rhodium‐Catalyzed C–H Bond Annulation for the Synthesis of 5‐ and 6‐Membered N‐Heterocyclic Building Blocks

The sustainable preparation of N‐heterocycles is one of the most active research areas owing to their predominance as synthetics building blocks with extensive applications in organic, pharmaceutical, and material chemistry fields. Among the various catalytic protocols, the C–H bond functionalization with the concomitant C–N bond formation, so‐called C–H bond annulation, has become one of the most sustainable routes to access N‐heterocycles because it starts from low‐functionalized materials and generates a limited amount of waste, all respecting the concept of atom economy. Rhodium complexes often catalyze these reactions. This review focuses on the synthesis of 5‐ and 6‐membered ring N‐containing heterocycles such as indoles, pyrroles, indolines, (iso)quinolinones, dihydroquinolines, and pyrrolidones from readily available starting materials, with an emphasis on the novel C–H bond cascade synthetic methodologies via C–N/C–C bond formation, as well as on the mechanisms of these reactions, especially the oxidation steps. We hope this review will help researchers looking to prepare N‐heterocycles in a minimum of steps and those who want to develop new methodologies based on C–H bond activation/functionalizations.

Strategy of Empowering Maritime Defense Areas to Increase the Income of Fisherman Communities and Awareness of National Defense in Banyuasin Regency, South Sumatra (Study at Palembang Naval Base)

Republic of Indonesia Law No.34 of 2004 regulating the Indonesian National Armed Forces Navy Duties in Article 9 Paragraph (e); Implementing the Empowerment of the Maritime Defense Area. The implementation of maritime defense area empowerment is the empowerment of coastal communities through Maritime Potential Development, which is implemented by Main Naval Bases III/JKT, in this case, Palembang Naval Base in Banyuasin district, South Sumatra, which is represented by the coastal area of Sungsan I-IV village, Banyuasin II subdistrict. From the perspective of the Indonesian National Armed Forces, the goal is to carry out the primary mission of the Indonesian Navy, which is to raise awareness of national defense. The main objective of this research is to investigate the strategy for empowering maritime defense areas by Main Naval Base III/JKT, specifically Palembang Naval Base, in terms of increasing coastal communities' economic income and awareness of national defense in Banyuasin district, South Sumatra. The findings of this research reveal that there is no coastal community/fishermen empowerment program in Banyuasin district, South Sumatra that is planned, measurable, and sustainable. According to Chamber, community empowerment is an economic development concept that encompasses social values. This notion reflects a new "people-centered" development paradigm that is participatory and sustainable. The concept of empowerment encompasses more than merely meeting fundamental needs or providing a mechanism to prevent future impoverishment. Conclusion: Coastal community empowerment measures intended to increase fishing communities' earnings along with comprehension of National Defense in Banyuasin Regency, South Sumatra, have not been planned.

Институциализация психологической помощи в системе высшего образования Российской Федерации

<p style="text-align: justify;">In the article, psychological assistance in the higher education system is analyzed in the context of its formation and development as a social institution — taking into account various scientific approaches to the definition of the concept of “Social institution”, including within the framework of the economic concept of growing social institutions and directed institutional changes, since this determines the role and place of psychological assistance in the life of society in general and the university community in particular, and also ensures its acceptance, recognition, sustainability and adaptability in changing historical conditions and socio-economic situation. In addition, recommendations are presented for the further development of the institute of psychological assistance in the system higher education in modern cultural and historical conditions.</p>