Sustainable Production Chain Research Articles

Design strategy for the prototyping of 3D-printed continuous fiber-reinforced components for solar-powered vehicle

Continuous fiber fused filament fabrication is an advanced 3D printing method that allows designers to produce high-performing lightweight structures, leading toward innovative design philosophies and sustainable production chains. In this work, we proposed a design strategy to manufacture selected components for a solar-powered vehicle, which consists of three stages. Firstly, the prototypes’ CAD models are developed, considering their geometric and manufacturing requirements. Then, a finite element analysis is carried out to ensure optimal fiber reinforcement of prototypes’ critical regions. Lastly, the manufacturing stage involves the slicing process and optimization of the time and cost of the printed part employing Markforged® technology. Adopting the proposed methodology, the experimental campaign investigated the print quality and performance of several prototypes of each component by adjusting printing parameters.

A CIRCULAR ECONOMY APPROACH TO PRODUCE LOW-COST BIODIESEL USING AGRO-INDUSTRIAL AND PACKING WASTES FROM MEXICO: VALORIZATION, HOMOGENEOUS AND HETEROGENEOUS REACTION ROUTES AND PRODUCT CHARACTERIZATION

This manuscript describes a circular economy approach to produce low-cost biodiesel using Tetra Pak (TP) and Mexican biomass wastes. Lipids were extracted from non-edible biomass with hexane. Corozo seeds contained 53 wt% lipids, while remaining biomass had <5 wt%. Corozo seed oil was selected to produce biodiesel with both homogeneous and heterogeneous reaction systems. A heterogeneous catalyst was synthesized from TP and its performance was compared with KOH in homogeneous systems using corozo and soybean oils. The best reaction conditions were identified through the Signal/Noise ratio analysis. TP catalyst achieved biodiesel yields of 12.7-98.11% (corozo) and 87.0-98.4% (soybean), while KOH systems showed 7.2-96.3% and 64.6-98.5%, respectively. These reactive systems were endothermic and fit to pseudo-second order kinetic model. Activation energies for KOH-catalyzed systems were 86.89 (corozo) and 43.72 (soybean) kJ/mol, while TP-catalyzed systems showed 78.31 and 105.68 kJ/mol, respectively. TP catalyst reuse was tested, and the loss of catalytic activity was attributed to active sites poisoning. Biomass, catalysts, and reaction products were characterized (e.g., FTIR, ICP, XRD, EDX-SEM, WDXRF, XPS, basicity and nitrogen adsorption isotherms). The TP catalyst showed competitive performance with respect to KOH, contributing to a sustainable biodiesel production chain viable for commercial implementation in Mexico.

From needs to policy action: Italian agri-food districts as a case of territorial cooperation

In the context of ecological and social challenges in global food systems, this study investigates the potential of agri-food districts to foster balanced territorial development. A multi-step approach to developing sustainable agri-food districts is outlined. How these districts, as integrated systems and meso-level organizational forms, can enhance sustainability through governance is then assessed. This research uses a context-driven analysis pathway involving stakeholder participation and needs identification. The theoretical background, the Italian regulatory framework, and a case study from Lombardy are presented. Needs are identified through participatory approaches and actions are prioritized using desk research and a narrative SWOT analysis combined with key stakeholder discussions (focus group). A total of eighteen needs are identified and categorized into 3 dimensions of sustainability: economic, environmental, and socio-institutional. Findings indicate that agri-food district organization has great potential to help achieve local and regional policy goals in line with the shift to sustainable approaches in the Common Agricultural Policy (CAP). The paper proposes actions to strengthen district capacity-building, focusing on internal governance and sustainable production chains. Additionally, initiatives to attract young people to rural areas and agreements for ecosystem services in agri-food districts are suggested. These actions aim to promote sustainability and competitiveness while addressing challenges related to governance, innovation, branding, demographics, and environment. In conclusion, the study prompts critical inquiry into governance models and system dynamics. The innovative aspects of this study lie in its methodological approach, integration of theory and practice, holistic perspective, policy relevance, and critical inquiry, which collectively contribute to advancing knowledge and understanding in the field of sustainable agriculture and territorial development.

CULTIVATING HOLISTIC APPROACHES TO SUSTAINABLE CONSTRUCTION: INSIGHTS FROM THE REAL-WORLD PROJECTS

This study examines the impact and performance of sustainable building practices through selected case studies. It assesses sustainable design, construction, production, and supply chains, emphasizing the use of advanced materials like Cross-Laminated Timber (CLT) and coated glass to enhance durability and energy efficiency while reducing environmental impact. Nanotechnology and wood innovation in construction are explored alongside insights into reducing energy consumption, utilizing renewable energy, and managing waste across a building's lifecycle. Case studies, including The Edge building in Amsterdam and the Treet building in Bergen, illustrate the efficacy of sustainable practices in creating enduring, eco-friendly structures. The study also highlights successful waste management techniques, exemplified by the Eden Project, demonstrating effective waste reduction, reuse, and recycling in construction. Overall, this research offers a comprehensive view of implementing sustainable building practices to achieve superior performance while minimizing environmental effects.

CMEMS-LSCE: a global, 0.25°, monthly reconstruction of the surface ocean carbonate system

Abstract. Observation-based data reconstructions of global surface ocean carbonate system variables play an essential role in monitoring the recent status of ocean carbon uptake and ocean acidification, as well as their impacts on marine organisms and ecosystems. So far, ongoing efforts are directed towards exploring new approaches to describe the complete marine carbonate system and to better recover its fine-scale features. In this respect, our research activities within the Copernicus Marine Environment Monitoring Service (CMEMS) aim to develop a sustainable production chain of observation-derived global ocean carbonate system datasets at high space–time resolutions. As the start of the long-term objective, this study introduces a new global 0.25∘ monthly reconstruction, namely CMEMS-LSCE (Laboratoire des Sciences du Climat et de l'Environnement) for the period 1985–2021. The CMEMS-LSCE reconstruction derives datasets of six carbonate system variables, including surface ocean partial pressure of CO2 (pCO2), total alkalinity (AT), total dissolved inorganic carbon (CT), surface ocean pH, and saturation states with respect to aragonite (Ωar) and calcite (Ωca). Reconstructing pCO2 relies on an ensemble of neural network models mapping gridded observation-based data provided by the Surface Ocean CO2 ATlas (SOCAT). Surface ocean AT is estimated with a multiple-linear-regression approach, and the remaining carbonate variables are resolved by CO2 system speciation given the reconstructed pCO2 and AT; 1σ uncertainty associated with these estimates is also provided. Here, σ stands for either the ensemble standard deviation of pCO2 estimates or the total uncertainty for each of the five other variables propagated through the processing chain with input data uncertainty. We demonstrate that the 0.25∘ resolution pCO2 product outperforms a coarser spatial resolution (1∘) thanks to higher data coverage nearshore and a better description of horizontal and temporal variations in pCO2 across diverse ocean basins, particularly in the coastal–open-ocean continuum. Product qualification with observation-based data confirms reliable reconstructions with root-mean-square deviation from observations of less than 8 %, 4 %, and 1 % relative to the global mean of pCO2, AT (CT), and pH. The global average 1σ uncertainty is below 5 % and 8 % for pCO2 and Ωar (Ωca), 2 % for AT and CT, and 0.4 % for pH relative to their global mean values. Both model–observation misfit and model uncertainty indicate that coastal data reproduction still needs further improvement, wherein high temporal and horizontal gradients of carbonate variables and representative uncertainty from data sampling would be taken into account as a priority. This study also presents a potential use case of the CMEMS-LSCE carbonate data product in tracking the recent state of ocean acidification. The data associated with this study are available at https://doi.org/10.14768/a2f0891b-763a-49e9-af1b-78ed78b16982 (Chau et al., 2023).

Water quality management in aquaculture

Abstract The aquaculture industry requires good water quality for its successful operation but produces wastes that can cause environmental deterioration and pose high risks to the sector. Adequate waste treatment and recycling are necessary to make aquaculture a sustainable and profitable industry and contribute to the circular economy. Polluted water sources, excess feeding, overstocking, use of antibiotics/chemicals and harmful algal blooms are major causes of water quality deterioration and low production in aquaculture systems. Discharges of untreated wastes would have serious impacts on the receiving water bodies, and eventually on the aquaculture industry itself. Possible solutions include technological innovations in environmentally friendly production systems, use of efficient processes in water quality management and improved legislation and governance. Environmentally feasible aquaculture production technologies such as recycling aquaculture system, integrated multi-trophic aquaculture and aquaponics including features of waste recycling are viable options in aquaculture schemes. Best aquaculture practices integrating advanced water quality treatment processes and technologies, supported by automation and sensors, modeling and artificial intelligence-internet of things are necessary for a sustainable aquaculture environment, production and stable value chain. In general, low-cost technologies for aquaculture waste treatment and environmental impact reduction through good governance are crucial for achieving sustainability in the aquaculture industry and natural environmental management.

Optimizing UVC-LED application to improve the shelf life of vacuum-packed refrigerated stored Nile tilapia (Oreochromis niloticus) fillets.

Although ultraviolet-C light-emitting diode (UVC-LED) has proven antimicrobial effectiveness doses needed to reach it cause adverse effects on the physicochemical quality of fish, and thus, optimization studies are crucial to boost its industrial application. This study aimed to identify optimal UVC-LED conditions for maximum shelf life extension with the least possible quality changes of refrigerated stored tilapia fillets from a central composite rotatable design (CCRD). UVC-LED powers (1, 1.38, and 1.58mW/cm2 ) and times (500, 1800, and 2700s) were set on the CCRD, which generated 11 treatments, including three replicate experiments. Treatments were analyzed for total aerobic psychrotrophic count, lipid oxidation, instrumental color, and texture parameters on days 0, 2, 4, 7, 11, and 14. The UVC-LED affected shelf life and physicochemical parameters in a nonlinear fashion. UVC-LED-treated fish had increased shelf life by 2.80-4.76 days and increase or decrease in lipid oxidation (0.025-0.276mg of malondialdehyde [MDA]/kg), total color change (∆E=3.47-9.06), and hardness (1.31-8.51N) over the refrigerated storage depending on specific UVC-LED conditions applied. The optimal UVC-LED condition was 0.97mW/cm2 with 2503.6s (2428.50mJ/cm2 ), which increased the fillet's shelf life by 2.5-fold (2 days) while maintaining quality closer to the original throughout refrigerated storage, resulting in ∆E<5, an increase of only 0.05mg of MDA/kg, and preservation of the decrease in hardness by 3.38N compared to its control counterparts. Therefore, it represents an eco-friendly technology that can easily scaled industrially to enhance the sustainable fish production chain. PRACTICAL APPLICATION: The high fish perishability is a global concern due to food safety risks and waste generation impacting the environment adversely, especially nowadays, where fish production and consumption have increased, and there are more evident efforts to sustainable production. UVC-LED is an eco-friendly technology with proven antimicrobial effectiveness but doses needed to reach this effect enhance oxidative degradation. Despite that, optimization studies concerning the maximum shelf life extension while retaining the physicochemical quality of refrigerated stored fish are a gap in the literature and a barrier to its industrial application. Our findings are helpful in sustainably enhancing the fish production chain.

Hybrid machine learning-metaheuristic model for sustainable agri-food production and supply chain planning under water scarcity

Hybrid machine learning-metaheuristic model for sustainable agri-food production and supply chain planning under water scarcity

Optimization models for sustainable insect production chains

Abstract Insect value chains are a complex system with non-linear links between many economic, environmental, and social variables. Multi-objective optimization (MOO) algorithms for finding optimal options for complex system functioning can provide a valuable insight in the development of sustainable insect chains. This review proposes a framework for MOO application that is based on gradual implementation, beginning with factors that have an immediate impact on insect production (feed qualities, resource utilization, yield), and progressing to integrated units (environmental, social, and economic impacts). The review introduces the key hotspots of insect production chains, which have been developed in suitable MOO objectives. They represent aspects of resource use, feed quality and its conversion by insects, labor safety and wage fairness, as well as environmental impacts. The capacity of the suggested MOO framework to describe all facets of sustainability may have certain limits. To determine the framework’s applicability and the specific MOO algorithms that can perform the function, modeling and further testing on real insect production chains would be necessary for the intended objectives.

Agave crop segmentation and maturity classification with deep learning data-centric strategies using very high-resolution satellite imagery

ABSTRACTThe responsible and sustainable agave-tequila production chain is fundamental for the social, environmental, and economic development of Mexico’s agave regions. It is therefore relevant to develop new tools for large-scale automatic agave region monitoring. In this work, we present an Agave tequilana Weber azul crop segmentation and maturity classification using very high-resolution satellite imagery, which could be useful for this task. To achieve this, we solve real-world deep learning problems in the very specific context of agave crop segmentation such as a lack of data, low-quality labels, highly imbalanced data, and low model performance. The proposed strategies go beyond data augmentation and data transfer combining active learning and the creation of synthetic images with human supervision. As a result, the segmentation performance evaluated with the Intersection over Union (IoU) value increased from 0.72 to 0.90 in the test set. The authors also propose a method for classifying agave crop maturity with 95% accuracy. With the resulting accurate models, agave production forecasting can be available for large regions. In addition, some supply-demand problems such as excessive supplies of agave or, deforestation, could be detected early.

Biorefineries as a driver for sustainability: Key aspects, actual development and future prospects

The overexploitation of resources, the increase of the world population and the trend of consumption based on “use and throw away” is causing an increasing pressure on waste management. In this sense, it is necessary to promote sustainable practices in the valorization of waste streams as a strategy for the co-production of bioproducts and bioenergy. This approach can lead to more sustainable production chains, as lower environmental burdens are expected. However, even if a promising cascade production technology could be used, the technical and economic feasibility of biorefineries remains a challenge. This report aims to provide various insights on how to assess biorefineries from a sustainability perspective, including also available standards and guidelines that enable reliable, accurate and transparent sustainability assessments. It also shows where to focus for the inclusion of biorefineries in the value chain, for communicate/visualize their potential, and for the promotion of bio-based products from recovered resources. The outcomes and main conclusions of this report could be summarized as the importance and the need of assessing biorefinery scenarios under a sustainable perspective to have an increased market potential, considering the main aspects available on the international guidelines, certification schemes and voluntary standards.

Towards greener trade and global supply chain environmental accounting. An embodied environmental resources blockchain design

International trade, through global supply chains, is central to global sustainable production and consumption. Redistribution of environmental resources impacts through international trade has become apparent in ecological research – and may have long-term design and planning implications for production and supply chain management. However, current trade and production accounting methods are still incapable of providing accurate and reliable results for policymakers and organisational decision makers to manage global and supply chain trade issues. In this study, a blockchain-based conceptual framework for embodied environmental resources accounting in trade is proposed to address global supply chain and trade issues. Framework design, benefits, and challenges are also discussed. Future research and linkage to theory are also provided. This study provides a strong systemic foundation for managing environmental resources at the nexus of international trade, sustainable production, and global supply chains.

Changes and Factors Determining the Efficiency of Cattle Farming in the State of Pará, Brazilian Amazon

Livestock production in the Brazilian state of Pará, located in the Amazon biome, faces challenges related to sustainable production chains and competitive production systems. Historically, expansion of pastures has led to environmental pressures and low productivity. The objective is to evaluate changes in cattle raising efficiency in the microregions of Pará state and identify the factors contributing to efficient cattle production at the state level. The data analysis techniques used include Data Envelopment Analysis, Malmquist Index, and Tobit Regression. The study found that, on average, there was a marginal improvement in livestock efficiency in Pará over the analyzed years, increasing from 0.75 (75%) in 2006 to 0.76 (76%) in 2017. However, nine out of 17 microregions showed improvement in individual efficiency, while five showed a decline. Non-family agriculture, livestock credit, and land prices were identified as factors that negatively contributed to the activity’s inefficiency, while specialization in soybeans and deforestation were factors that positively contributed to inefficiency. The study suggests that financial support for technological and infrastructure improvements, more rigorous environmental policies, and a more competitive environment can further contribute to improving the efficiency of cattle farming in Pará.

Development support of agricultural cooperation in Ukraine by public institutions

Problem statement. It is important to encourage entrepreneurial activity in various areas for the development of rural areas. One of the means of boosting local economic development is to promote the formation and development of agricultural cooperatives. Analysis of recent research and publications. In order to create effective conditions for the development of agricultural cooperatives, scientists and experts suggested the following ways: informational support of the agricultural cooperative movement by the state; easing tax pressure; strengthening cooperation between agricultural cooperatives and higher education institutions; using international experience of cooperation between commodity producers; development of advisory and consulting services in the field of functioning of agricultural cooperatives, etc. Under the conditions of war and in the post-war period, the proposals given by FAO specialists are relevant, in particular: to include small landowners and cooperatives, especially those located in the affected areas, in sustainable production chains. In general, a wide range of experts and scientists considered the topic of the activities of agricultural cooperatives in Ukraine. At the same time, the practice of cooperatives functioning in Ukraine and changes in legislation require reasonable proposals to support the development of agricultural cooperation. Highlighting the previously unsolved parts of the general problem. Opportunities detection for support from various public institutions and improving legislation are important areas of research regarding the further development of agricultural cooperation in Ukraine. Presentation of the main material. In November 2020, the updated law of Ukraine “On agricultural cooperation” came into force. The new law defines that members of an agricultural cooperative can choose whether to be a profitable organization or to work with no purpose of making a profit. The generated profit can be reinvested in promising business initiatives. The additional opportunities that producers receive through participation in agricultural cooperatives are primarily related to facilitating the product’s sale. One of the advantages is the possibility of joint financing by participants of agricultural cooperatives of product storage processes. Various public institutions can contribute to agricultural cooperation development in accordance with their capabilities. Thus, experts suggest that the Agricultural Exchange consider the possibility of accreditation of agricultural cooperatives under a simplified system and provide them with holidays to pay the exchange fee. There is a positive experience of assistance in the formation and development of agricultural cooperatives by advisory services. Agricultural cooperatives receive additional opportunities to access material and financial resources thanks to international technical assistance. The result of such assistance is not only an increase in revenues to local budgets from the operation of business entities but also the creation of new jobs and the unification of people living in territorial communities. It will be advisable to identify in the territorial community a person, responsible for consulting and training on agricultural cooperation in the context of expanding the powers of local self-government bodies. An example of cooperation between public organizations, experts, and local governments is their participation in the EU4Business International Technical Assistance Program: Competitiveness and Internationalization of Small and Medium-sized Enterprises in 2021–2022. It is also planned to conduct a series of training on the development of entrepreneurship, including agricultural cooperation at the following program stages. Conclusions and prospects for further research. Since local self-government bodies and public organizations are the closest to entrepreneurship, their activity and communication with the population of rural areas can contribute to the expansion of the development of agricultural cooperation. Expert consulting services in the field of agricultural cooperation development can be provided by educational institutions, advisory services, various public organizations, and other public institutions. Further research should be directed to the dissemination of the territorial communities' experience where agricultural cooperatives are successfully functioning.

A Systematic Review on Lithium-Ion Battery Disassembly Processes for Efficient Recycling

Recycling plays a crucial role in achieving a sustainable production chain for lithium-ion batteries (LIBs), as it reduces the demand for primary mineral resources and mitigates environmental pollution caused by improper disposal. Disassembly of the LIBs is typically the preliminary step preceding chemical recovery operations, facilitating early separation of components consisting of different materials. Despite that extensive research has been conducted on the chemical processes involved in the recycling of LIBs, systematic studies on disassembly processes in the recycling process are relatively scarce. In this research, a systematic review was conducted on the publications from major databases, such as Scopus, SpringerLink, and others, to explore the current state of disassembly processes in LIBs’ recycling. The results emphasize disassembly as a crucial process for achieving a high material separation rate and ensuring a high degree of purity of the recycled active material. Moreover, automated disassembly can significantly raise productivity and reduce disassembly costs. Thus, it improves disassembly efficiency and increases economic as well as environmental benefits. Most researchers have focused on disassembly at the pack or module level. Investigation into extending the disassembly depth from cell to individual components is limited, particularly in automated approaches. Therefore, further research is highly recommended to explore the feasibility and potential of novel automated disassembly procedures at the cell level. This can contribute to improving the efficiency and sustainability of the recycling process for LIBs.

Culturing the lined seahorse (Hippocampus erectus) in extensive shrimp ponds and cages

AbstractThe aim of the present study was to develop low‐cost techniques for culturing seahorses in extensive shrimp ponds to foster a legal and more sustainable production chain to meet market demand for traditional Chinese medicine. In the present article, the results of two‐year experiments of seahorse culture in cages and extensive shrimp ponds are reported. We found that juveniles of the lined seahorse survived in cages and ponds very well, and the juvenile survival generally was &gt;70% during the experimental periods. The survival and growth of the juveniles were similar to or even better than that reported in indoor tank culture. Additionally, the lined seahorse survived well (&gt;60%) at temperatures up to 34.6°C which is the highest recorded temperature for the species in the field. For large ponds of &gt;5 ha, cage culture may be a better way. For small ponds of &lt;0.3 ha, culturing the seahorse in a pond is recommended. A 1000 m2 pond could support around 7000 of the juveniles of the lined seahorse. In conclusion, culturing the lined seahorse in an extensive shrimp pond is technically feasible.

Advances in the Food Packaging Production from Agri-Food Waste and By-Products: Market Trends for a Sustainable Development

Agricultural waste has been a prominent environmental concern due to its significant negative impact on the environment when it is incinerated, disposed of in landfills, or burned. These scenarios promoted innovations in the food packaging sector using renewable resources, namely agri-food waste and by-products such as bagasse, pulps, roots, shells, straws, and wastewater for the extraction and isolation of biopolymers that are later transformed into packaging materials such as bioplastics, biofilms, paper, and cardboards, among others. In this context, the circular bioeconomy (CBE) model is shown in the literature as a viable alternative for designing more sustainable production chains. Moreover, the biorefinery concept has been one of the main links between the agri-food chain and the food packaging industry. This review article aimed to compile recent advances in the food packaging field, presenting main industrial and scientific innovations, economic data, and the challenges the food packaging sector has faced in favor of sustainable development.

Risk assessment of human Hg exposure through consumption of fishery products in Ceará state, northeastern Brazil

The contamination of fish and aquaculture products may prove an obstacle to achieve the economic potential of the fishery sector worldwide. Seafood is a key source of Hg exposure to human consumers. Thus, it is necessary to monitor current contamination levels and formulate future scenarios of exposure to pollutants as supporting measures to improve, in the short and medium term, the sustainability of the fishing sector and guarantee food safety. In the short term, players in the private sector and governmental agencies need to provide up-to-date production data and to follow international recommendations, as it relates to seafood quality and sustainable production chains. Here, we provide an assessment of the fishery production in Ceará State, Brazil, and synthetize the present knowledge on Hg concentrations in fisheries and aquaculture products associated with their relative economic and consumers' diet relevance. The present assessment serves as a model study to produce a regionalized inventory of Hg concentrations in accordance with the national and international food safety guides and to estimate the risk of exposure to Hg of human populations through fisheries consumption. We show that legal Hg limits does not represent safe consumption levels, as exposure risk is a combined effect of trophic level, a proxy of Hg concentrations, consumption rates, and consumer age/weigh group. Most seafood species in Ceará have no restriction to human consumption, with a few exceptions. Children at a subsistence level mainly consuming fish are at most exposure risk. The overall information is graphically presented aiming to increase public perception on the theme and proposition of mitigating actions by the respective stakeholders.

Microbiological and chemical safety ofBombyx mori farmed in north-eastern Italy as a novel food source

Sericulture in Italy has old origins, but competitiveness with the Asian markets and the widespread use of pesticides have led, in the past, to a decline ofBombyx mori (BM) farming. However, this sector is characterised by future development potential due to the use of all BM products in the food sector, which would promote a sustainable production chain. The aim of the present study was to determine the nutritional composition and the presence of chemical and microbiological hazards in BM. Based on the microbiological criteria reported by the Regulation (EU) 2017/2470 and amendments for already authorised edible insect species, the samples of chrysalides met the criteria set forEscherichia coli, Listeria monocytogenes, Salmonella spp., Bacillus cereus, Coagulase positive Staphylococci, and sulphite-reducing anaerobes. Some samples were not compliant with the criteria set for total aerobic colony count,Enterobacteriaceae, yeasts and moulds. B. cereus was detected only in cocoon samples. Traces of fungicides, polycyclic aromatic hydrocarbons, dioxins-PCBs and heavy metals (Pb and As) were observed in chrysalides, chrysalis oil and defatted chrysalis meal. Cd and Hg were not detected in any sample. Traces of mycotoxins were detected only in chrysalis oil and defatted chrysalis meal, not in chrysalides. The content of lipids and proteins in chrysalides ranged between 34.42-39.19% and 38.13-50.17%, respectively. In addition, no difference was observed in element content (P, S, Cl, K, Ca, Mn, Fe, Cu, Zn) between chrysalides and chrysalis meal. The present study highlights the possible impact of contamination of the rearing and processing environments on the microbial and chemical safety of BM and derivative products.

Proper modelling of industrial production systems with unintended outputs: a different perspective

The question of how to properly model production systems with unintended outputs has proven both controversial and of particular interest to the productivity and efficiency community. The paper explains why some of the arguments put forward in these controversies are hardly convincing for industrial and other processes. Among other things, there is a lack of clear conceptual labelling of the different types of joint production, especially coupled production, which is the main source of undesirable and other unintended outputs, unless neglected. It is largely ignored that the desirability of such by-products may depend on the quantity produced. This is also true for reduction processes such as waste incineration or end-of-life vehicle dismantling, which in turn generate new unintended outputs. As a rule, industrial material and energy balances are modelled implicitly. Koopmans’ activity analysis is the standard approach in modelling production systems with undesirable outputs in the literature of business economics on sustainable production and supply chain management. With data envelopment analysis (DEA), instead of entire production possibilities, it is sufficient to know only certain local properties in the relevant range of input and output quantities of the observed activities. This lowers the challenge to verify their empirical validity.