The bioeconomy is generally understood as an economy in which sustainably-sourced renewable bio-based resources are used for the production of food, energy and other products and services. ...Expectations are high for its potential to support the transition away from a fossil fuel-based economy and help to address complex issues such as climate change and biodiversity depletion. However, given its cross-sectoral nature and key focus on innovation, tensions can emerge between bioeconomy goals and the need for regulation of bioeconomy activities. In particular, there is a recognition of the need for regulation to (a) support sustainability and resource efficiency, (b) manage competing interests and (c) provide coherence and innovation support. To identify how regulation may be acting as a barrier and / or driver of the bioeconomy in Ireland, interviews were conducted with a range of key stakeholder organisations. Analysis revealed four key barriers, relating to the need for financial support tools such as feedin tariffs, more flexible approaches to regulating the use of waste materials, closing the gap between regulation and innovation activity and addressing planning issues. The two drivers identified highlight a positive role for regulation in supporting and enabling bioeconomy development, especially in terms of using more flexible and innovative approaches. Associated challenges include the need to support genuine public participation and the provision of resources to support policy-makers in the design and implementation of an effective bioeconomy regulatory framework.
Increasing resource demand, predicted fossil resources shortage in the near future, and environmental concerns due to the production of greenhouse gas carbon dioxide have motivated the search for ...alternative ‘circular’ pathways. Among many options, microalgae have been recently ‘revised’ as one of the most promising due to their high growth rate (with low land use and without competing with food crops), high tolerance to nutrients and salts stresses and their variability in biochemical composition, in so allowing the supply of a plethora of possible bio-based products such as animal feeds, chemicals and biofuels. The recent raising popularity of Circular Bio-Economy (CBE) further prompted investment in microalgae, especially in combination with wastewater treatment, under the twofold aim of allowing the production of a wide range of bio-based products while bioremediating wastewater. With the aim of discussing the potential bio-products that may be gained from microalgae grown on urban wastewater, this paper presents an overview on microalgae production with particular emphasis on the main microalgae species suitable for growth on wastewater and the obtainable bio-based products from them. By selecting and reviewing 76 articles published in Scopus between 1992 and 2020, a number of interesting aspects, including the selection of algal species suitable for growing on urban wastewater, wastewater pretreatment and algal-bacterial cooperation, were carefully reviewed and discussed in this work. In this review, particular emphasis is placed on understanding of the main mechanisms driving formation of microalgal products (such as biofuels, biogas, etc.) and how they are affected by different environmental factors in selected species. Lastly, the quantitative information gathered from the articles were used to estimate the potential benefits gained from microalgae grown on urban wastewater in Campania Region, a region sometimes criticized for poor wastewater management.
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•Microalgae grown on wastewater is a promising circular pathway.•Depending on the microalgae species, several bio-based products can be gained.•This review maps the products obtainable from algae and their possible applications.•Potential economic and environmental benefits at global and local level are discussed.
Natural fibers are becoming a key point for the development of new concrete mixes because these fibers are recovered from residual biomass. In this paper, we focus on the natural fib‘ers found in the ...Metropolitan District of Quito, Ecuador. For this purpose, we searched for materials (fibers) available in the Chemical Engineering laboratory at Universidad San Francisco de Quito USFQ. In this paper, we analyze different literature on how the use of fibers influences the mechanical properties of concrete. Based on this analysis and the materials at the laboratory, we have developed recommendations on which natural fibers are of interest for further experimental research. Furthermore, this paper provides an understanding of how natural fibers influence the mechanical properties of concrete. It also proposes a process for the selection and study of any type of natural fiber for further replicability in mix analysis.
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•Organic waste is a renewable feedstock for biohydrogen production.•Low H2 yield and accumulation of acid metabolites are major technical glitches.•Process integration would be ...required for economically viable biohydrogen production.•The closed-loop waste biorefinery approach leads to a circular bioeconomy.
The present fossil fuel-based energy sector has led to significant industrial growth. On the other hand, the dependence on fossil fuels leads to adverse impact on the environment through releases of greenhouse gases. In this scenario, one possible substitute is biohydrogen, an eco-friendly energy carrier as high-energy produces. The substrates rich in organic compounds like organic waste/wastewater are very useful for improved hydrogen generation through the dark fermentation. Thus, this review article, initially, the status of biohydrogen production from organic waste and various strategies to enhance the process efficiency are concisely discussed. Then, the practical confines of biohydrogen processes are thoroughly discussed. Also, alternate routes such as multiple process integration approach by adopting biorefinery concept to increase overall process efficacy are considered to address industrial-level applications. To conclude, future perspectives besides with possible ways of transforming dark fermentation effluent to biofuels and biochemicals, which leads to circular bioeconomy, are discussed.
Conceptualizing waste biorefinery for recovery of value added products. Display omitted
•Resource recovery of bioenergy and platform chemicals from waste.•Biorefinery as a sustainable approach for ...waste mining.•Exploitation of waste would enhance biorefinery competitiveness & social acceptance.
Increased urbanization worldwide has resulted in a substantial increase in energy and material consumption as well as anthropogenic waste generation. The main source for our current needs is petroleum refinery, which have grave impact over energy-environment nexus. Therefore, production of bioenergy and biomaterials have significant potential to contribute and need to meet the ever increasing demand. In this perspective, a biorefinery concept visualizes negative-valued waste as a potential renewable feedstock. This review illustrates different bioprocess based technological models that will pave sustainable avenues for the development of biobased society. The proposed models hypothesize closed loop approach wherein waste is valorised through a cascade of various biotechnological processes addressing circular economy. Biorefinery offers a sustainable green option to utilize waste and to produce a gamut of marketable bioproducts and bioenergy on par to petro-chemical refinery.
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•Waste substrates or recycling of waste stream reduce cost and energy input for PHA production.•Recycling of waste streams and residual biomass has closed the gap in the circularity ...of the system.•Social and political factors need to be considered for effecting implementation of circular bioeconomy.
Research insight into the technical challenges of bioplastics production has revealed their confoundedness in their niche markets and struggles to enter the mainstream. There is an increasing problem of waste disposal and high cost of pure substrates in polyhydroxyalkanoates (PHA) production. This has led to the future need of upgrading the waste streams from different industries into the role of feedstocks for production of PHA. The review covers the latest developments in using wastes and surplus materials for PHA production. In addition to inexpensive carbon sources, efficient upstream and downstream processes and recycling of waste streams within the process are required to maintain the circularity in the entire process. A view on the link between circular bioeconomy and PHA production process covering the techno-economic, life cycle assessment and environmental aspects has also been provided. Furthermore, the future perspectives related to the topic have also been discussed.
The utilisation of waste biomass in biodiesel production as a sustainable energy source can lead to the incorporation of circular bioeconomy principles in the current economic systems. Herein, we ...synthesised a magnetically recyclable solid acid catalyst for the esterification of waste date seed oil. The catalysts possessed superparamagnetic behaviour and high saturation magnetisation, allowing them to be easily separated from the reaction mixture using an external magnetic filed. The esterification reaction was modelled and optimised by RSM (Design Expert program) and parametric study. The magnetic solid acid catalyst showed high catalytic performance with 91.4% biodiesel yield with optimum conditions of residence time, catalyst loading and temperature of 47 min, 1.5 wt %, and 55 °C, respectively. The solid catalyst was easily recovered by simple magnetic decantation and reused five consecutive times without significant degradation in its catalytic activity. This approach of using waste date seed coupled with cheap magnetic solid acid catalyst has the potential to create more sustainable and cost-effective catalytic systems for biodiesel production. This will complete the full cycle of waste date seed sustainably and facilitate the development of circular bioeconomy. The LCA results by using CML-IA baseline V3.06 midpoint indicators, for 1000 kg of biodiesel production showed the cumulative abiotic depletion of fossil resources over all the processes as 19037 MJ, global warming potential as 1114 kg CO2 eq, and human health toxicity as 633 kg 1,4-DB eq (kg 1,4 dichlorobenzene equivalent). The highest damage in all categories was observed during catalyst preparation, and reuse, which was also confirmed in endpoint LCA findings performed using ReCiPe 2016 Endpoint (E) V1.04.
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•Valorization of sustainable waste date seed into biodiesel fuel.•Synthesis of magnetic solid acid catalyst using iron-oxide and mercaptoacetic acid.•Biodiesel production was modelled and optimised by RSM (Design Expert program).•Practical and mathematical results showed good matching in esterification reaction.•Magnetic acid catalyst showed a biodiesel yield of 90% in low residence time.
Naturally synthesized compounds have an evolving market demand as bioactive metabolites with numerous health benefits. In this context, microalgae-based bioactive compounds such as pigments and ...nutraceuticals are commercially available, and it is foreseen that the market demand would continue to grow due to the recent requirement for natural products in the food industry. In particular, the global market for microalgae-based proteins is foreseen to reach $ 0.84 billion by 2023, whereas the natural blue pigment (c-phycocyanin) is expected to reach a market value of $ 409.8 million by 2030. Being a protein-rich cyanobacterium (60–70% (w/w)) and a promising source for c-phycocyanin (47% of the total proteins), Spirulina has gained attention as a promising feedstock for the large-scale production of high-value proteins and c-phycocyanin. Even though Spirulina is commercially cultivated in many countries, the exclusive production of proteins and c-phycocyanin is still emerging. Besides, Spirulina-based biorefinery is a promising strategy to enhance the economic viability of the large-scale production of proteins and c-phycocyanin. In addition, utilization of waste resources in Spirulina-based biorefineries is a beneficial strategy in terms of increasing economic feasibility and environmental sustainability. The current review focuses on promoting a circular bioeconomy via the biorefining of Spirulina to produce protein and c-phycocyanin while analyzing the challenges and future perspectives associated with the overall process.
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•Spirulina is a feedstock for the large-scale production of proteins and c-phycocyanin.•Two-stage cultivation is advantageous for large-scale cultivation of Spirulina.•Integrated biorefining increases the economic feasibility of large-scale production.•Conceptual Spirulina-based biorefinery with proteins and c-phycocyanin is proposed.
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•Anaerobic digestion process of food wastes for biogas production was reviewed.•Mechanical and alkali pre-treatment process enhances the hydrolysis for high production of ...biomethane.•Various techniques for the upgradation of biogas into biomethane have been discussed in depth.•Circular bioeconomy, techno economic effect and end use of biomethane are summarized.
Biogas production from food waste with anaerobic digestion process and co-digestion process obtained high purity of biogas. Food waste consists of proteins, carbohydrates, inorganic compounds, fibre, sugars, and lipids. Fossil fuels have caused some environmental and human health problems, such as effects of global warming, greenhouse gas emissions. Biogas production is a simple process and is purified into methane and used in many applications, heat, electricity and vehicle fuel. Different types of food waste are collected and processed into biogas, which is essential for human use and as an alternative to fossil fuels. The collection of food waste, pre-treatment process, production of biogas, purification of biogas, upgradation of biomethane, and circular bioeconomy are clearly explained. Anaerobic digestion and co-digestion processes have increased biomethane yield, up gradation and purification of biogas have also been discussed. Five different types of upgradation processes are included, such as physical scrubbing, chemical scrubbing, pressure swing adsorption, membrane separation, and cryogenic separation. The upgradation process and the purity level also mentioned in this review, it represents the biomethane quality. Techno economic effects and circular bioeconomy levels are addressed in this review. Life cycle assessment, life cycle impact analysis and environmental impact level are discussed. However, Challenges and future perspectives of biogas production and to improve the biomethane purity level. 89% of the biogas production is obtained from fruit waste with anaerobic digestion, after the upgradation process, 99% purity of biomethane is separated.
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