Fossil fuels are currently the most significant energy sources. They are expected to become less available and more expensive, leading to a great demand for energy conservation and alternative energy ...sources. As a sustainable and renewable energy source, Biomass has piqued interest in generating bioenergy and biofuels over recent years. The thermal conversion of biomass through pyrolysis is an easy, useful, and low-cost process that can be applied to a wide variety of feedstocks. Pyrolysis characteristics of different feedstock samples can be analyzed and examined through thermogravimetric analysis (TGA). TGA has been an essential tool and widely used to investigate the thermal characteristics of a substance under heating environments, such as thermodegradation dynamics and kinetics. Studying the potential of waste biomass for generating sustainable bioenergy carves a pathway into a circular bioeconomy regime, and can help tackle our heavy reliance on nonrenewable energy sources. This study aims to give a deep insight into the wide use of TGA in aiding in the research and development of pyrolysis of different waste biomass sources. The thermal characteristics portrayed by different biomass wastes through TGA are discussed. The effects of significant pyrolysis operating parameters are also illustrated. A more comprehensive understanding of evolved products during the pyrolysis stage can be gained by combining TGA with other analytical methods. The pros and cons of using TGA are also outlined. Overall, an in-depth literature review helps identify current trends and technological improvements (i.e., integrating artificial intelligence) of TGA use with pyrolysis.
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•The implementation of thermogravimetric analysis for pyrolysis studies is reviewed.•TGA data aids in developing kinetic parameters and studying reaction mechanisms.•The utility of TGA can be heightened by coupling it with other techniques.•TGA serves as a preliminary analysis for bioenergy development to achieve a circular bioeconomy.•Introducing AI into the bioenergy sector provides remarkable modeling efficiency.
•Latest approaches on green hydrogen were reviewed.•Possible pathways to a hydrogen-capable clean energy future were discussed.•The economics of hydrogen supply were highlighted.•Strategic ...considerations and applications of green hydrogen were provided.
Today, the generation of carbon-neutral hydrogen from renewable energy can be considered a significant achievement toward a circular bioeconomy in this industry. In contrast, carbon production is rising globally, with energy-related carbon emissions accounting for two-thirds of global emissions. Now, an energy factor is required to mitigate the correlation between economic growth and rising carbon emissions. This is where green hydrogen generation can enter the renewable energy equation. Hydrogen can contribute to reducing gas emissions in the coming decades, not only as a potential technology for the future but also as a successful technology already being implemented globally. This review aims to contribute to reducing greenhouse gas emissions, including carbon, by examining the possible pathways to a hydrogen-capable clean energy future. To this end, this article has challenged a deeper perspective on the relationship between hydrogen as a green fuel and renewable energy, as well as the economics of hydrogen supply considering the steadily declining costs of renewables and the role of hydrogen in energy transport as well as provides strategic considerations and applications.
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•Resource efficiency is a key circular bioeconomy concept.•Microalgae based wastewater treatment results in beneficial biomass.•Outdoor open ponds with sufficient light supply ...enhances microalgal growth.•Nutrient dissipation by abiotic methods needs to be controlled.•Techno economic evaluation and LCA are required for effective implementation.
The basic concepts of circular bioeconomy are reduce, reuse and recycle. Recovery of recyclable nutrients from secondary sources could play a key role in meeting the increased demands of the growing population. Wastewaters of different origin are rich in energy and nutrients sources that can be recovered and reused in a circular bioeconomy perspective. Microalgae can effectively utilize wastewater nutrients for growth and biomass production. Integration of wastewater treatment and microalgal cultivation improves the environmental impacts of the currently used wastewater treatment methods. This review provides comprehensive information on the potential of using microalgae for the recovery of carbon, nitrogen, phosphorus and other micronutrients from wastewaters. Major factors influencing large scale microalgal wastewater treatment are discussed and future research perspectives are proposed to foster the future development in this area.
•Coupling of insect production with food chain.•Nutrient recovery from food waste.•Implementation of sustainability and circularity concepts in insect processing.
Food loss and waste are serious ...threats to the sustainability of our food systems. Innovative and multi-faced solutions are continuously being proposed, tested and implemented by researchers, government authorities, non-government bodies and food industries to tackle this problem of food waste. Insect-based bioconversions have been reported as a marketable solution for reducing food waste. This rather novel approach can efficiently convert several tonnes of food waste into valuable products including human food, animal feed, fertiliser and other secondary industrial compounds. This paper couples the production of edible insects with the valorisation of food waste, providing an attractive key for closing the loop of food value chain. Current status of insect processing and their importance in circular economy is also discussed in detail.
•Biochar may facilitate a circular bioeconomy for agricultural waste.•Stochastic cost modeling is used to evaluate uncertainty in cost estimations.•Production costs ∼$448.78–$1,846.96 (USD) Mg−1 ...biochar.•A biochar enterprise budget is provided as supplemental material.•Indirect and induced regional economic benefits are shown.
It is well established that the global practice of burning crop residues, such as orchard biomass, harms human health and the environment. A bioeconomy for orchard biomass may reduce open burning, facilitate the recovery of nutrients that improve soil health, and boost economic growth. We present a techno-economic analysis for converting orchard waste into biochar, a charcoal-like substance that shows promise for improving soil health, but that is considered an experimental product with emerging efficacy and limited market demand. We impute values derived from a cost analysis of biochar production in California’s Central Valley into a regional economic input-output model to demonstrate economic growth and a bioeconomy for biochar made with orchard waste. Results from a stochastic Monte Carlo simulation show a probable range of biochar production costs between $448.78 and $1,846.96 (USD) Mg−1, with 90% probability that costs will range between $571 and $1,455 Mg−1. A sensitivity analysis shows that production costs are most responsive to biochar production rates. A modifiable Excel-based biochar enterprise budget that includes fixed and variable biochar production costs is provided as Supplementary Material. The regional economic analysis demonstrates positive economic growth as defined by job creation, labor compensation, value-added product, and gross output. Stochastic cost estimates and net positive regional economic impacts support economic feasibility of a circular bioeconomy for waste orchard biomass when coupled with governmental policy initiatives. Results may contribute to developing a circular bioeconomy for biochar and orchard biomass in the study region and elsewhere in the world.
This review discusses the classification, characteristics, and applications of biosurfactants. The biosynthesis pathways for different classes of biosurfactants are reviewed. An in-depth analysis of ...reported research is carried out emphasizing the synthetic pathways, culture media compositions, and influencing factors on production yield of biosurfactants. The environmental, pharmaceutical, industrial, and other applications of biosurfactants are discussed in detail. A special attention is given to the biosurfactants application in combating the pandemic COVID-19. It is found that biosurfactant production from waste materials can play a significant role in enhancing circular bioeconomy and environmental sustainability. This review also details the life cycle assessment methodologies for the production and applications of biosurfactants. Finally, the current status and limitations of biosurfactant research are discussed and the potential areas are highlighted for future research and development. This review will be helpful in selecting the best available technology for biosynthesis and application of particular biosurfactant under specific conditions.
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•Types of biosurfactants and their biosynthesis pathways.•Factors influencing production of biosurfactants.•Application of biosurfactants and associated mechanisms.•Circular bioeconomy and life cycle assessment of biosurfactants.•Current limitations and potential areas for research and development.
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•Composition of MSW plays critical role in determining the most effective WtE technique.•Waste-to-energy technologies for MSW management have been narrated.•Biorefinery aspects of ...municipal solid waste (MSW) are explained in detail.•Bio-electrochemical processes are capable of generating bioenergy from MSW.
Increasing municipal solid waste (MSW) generation and environmental concerns have sparked global interest in waste valorization through various waste-to-energy (WtE) to generate renewable energy sources and reduce dependency on fossil-derived fuels and chemicals. These technologies are vital for implementing the envisioned global “bioeconomy” through biorefineries. In light of that, a detailed overview of WtE technologies with their benefits and drawbacks is provided in this paper. Additionally, the biorefinery concept for waste management and sustainable energy generation is discussed. The identification of appropriate WtE technology for energy recovery continues to be a significant challenge. So, in order to effectively apply WtE technologies in the burgeoning bioeconomy, this review provides a comprehensive overview of the existing scenario for sustainable MSW management along with the bottlenecks and perspectives.
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•State-of-the-art review on biobased refineries as a prototype to a circular economy.•Elaboration on the potential substrates and products for the future circular economy.•Insightful ...discussion on techno-economic, environmental, and social impacts.•An explicit account of the case studies and international biorefinery policies.•Future perspective of exploiting current petroleum refinery for biorefineries.
Fossil based resources are a major contributor to energy and chemicals to modern-day development. The negative environmental impacts of fossil-based resources accompanied by its fast depletion has alerted the scientific community and governments to find an alternative source. Biobased biorefineries are dependent on the natural organic biomass for the generation of biofuel and biochemicals. The present review is a comprehensive account of biobased biorefineries focusing on substrates, processes that include existing conventional and advanced biotechnologies approaches for its successful implementations on a large scale. The environmental, life cycle, socio-economic sustainability, and policy decision of biobased refineries are also discussed. Further, it can be the potential future alternative to fulfill the dream of a biobased circular economy. The review suggests that biomass being abundantly available and has great potential to be used for the generation of biofuel and biochemicals due to the technological advances available in the area. The integration of biobased refineries steps into existing petrochemical refineries structure can facilitate sustainable development replacing fossil-based products without the need of developing new infrastructures. The concept of utilization of biomass in the biobased refineries can act as a model system for the future circular bioeconomy.
Acceleration of urbanization and industrialization has resulted in the drastic rise of waste generation with majority of them being biowaste. This constitutes a global challenge since conventional ...waste management methods (i.e., landfills) present environmental issues including greenhouse gases emissions, leachate formation and toxins release. A sustainable and effective approach to treat biowaste is through composting. Various aspects of composting such as compost quality, composting systems and compost pelletization are summarized in this paper. Common application of compost as fertilizer or soil amendment is presented with focus on the low adoption level of organic waste compost in reality. Rarely known, compost which is easily combustible can be utilized to generate electricity. With the analysis on critical approaches, this review aims to provide a comprehensive study on energy content of compost pellets, which has never been reviewed before. Environmental impacts and future prospects are also highlighted to provide further insights on application of this technology to close the loop of circular bioeconomy.
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•Conversion of waste to compost can reduce environmental pollution of organic waste.•Composting process, compost quality and composting systems are critically reviewed.•Compost can be utilized as fertilizer and energy fuel, promoting circular economy.•Production and combustion of compost fuel have high efficiency of energy recovery.•Optimizing composting process and composter can mitigate the environmental impacts.
This paper reviews composting process and utilization of compost for fertilizer and bioenergy to reduce waste volume, mitigate pollution and promote circular bioeconomy.
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