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This paper describes an economic analysis of the GoBiGas plant, which is a first‐of‐its‐kind industrial installation for advanced biofuel production (ABP) via gasification, in which woody biomass is converted to biomethane. A previous technical evaluation of the demonstration unit confirmed that it is technically feasible to construct advanced biofuel production plants, using commercially available and widely used components. Thus, significant cost reductions for equipment cannot be expected as a consequence of learning effects. However, the equipment itself accounted for <20% of the total investment cost at GoBiGas and there exists the potential to reduce the production cost through learning how to assemble the process and reduce project‐specific costs. The analysis shows that a plant with capacity of 200 MW of biomethane is an attractive scale for future stand‐alone ABP plants with respect to limiting the production cost. For a 200‐MW ABP plant operated using forest residues as fuel, the production cost for biomethane is estimated at approximately 600 SEK/MWh, (60€/MWh, 75US$/MWh), which is equivalent to 5.4 SEK/liter gasoline [0.54 €/liter, or 2.5USD per gallon (9.9 SEK/€, 8 SEK/USD)], where the feedstock accounts for about 36% of the production cost. The most significant uncertainty factors pertaining to the estimated production costs are expected to relate to: trade conditions; the location of the installation; and the local price of feedstock. Thus, there is some potential for implementing cost‐competitive ABP systems of smaller capacity if low‐grade feedstocks (eg, waste‐derived woody biomass) can be utilized, and/or if the unit can be integrated with the already existing infrastructure. In this paper, we describe an economic analysis of the GoBiGas plant, which is a first‐of‐its‐kind industrial installation for advanced biofuel production (ABP) via gasification, in which woody biomass is converted to biomethane. [ABSTRACT FROM AUTHOR]

• Glycerol-consuming Y. lipolytica can utilize glucose for efficient SA production. • First study for utilizing organic MSW in SA production by Y. lipolytica at low pH. • The highest SA yield of 0.61 g/g ever reported by yeast at low pH was achieved. • Fed-batch fermentation using waste hydrolysate at pH 2.8 resulted in 71.6 g/L SA. • Low pH SA production led to economic improvement and environmental sustainability. This paper presents an efficient, green and sustainable approach for succinic acid (SA) fermentation, in which glucose-rich hydrolysates from various waste streams were used as the substrate for SA production by Yarrowia lipolytica without pH control for the first time. First, Y. lipolytica PGC202 was found to be able to consume glucose-rich mixed food waste (MFW) hydrolysate for SA production with high efficiency. After medium optimization, a SA titer at 31.7 g/L with a yield of 0.52 g/g and productivity of 0.60 g/L/h was obtained from is FBB fermentation when using 60 g/L glucose-containing MFW hydrolysate as the carbon source supplemented with 3% tryptone. When glucose-rich hydrolysate from other waste streams was used, the highest SA yield of 0.61 g/g via yeast fermentation at low pH was achieved, which demonstrated the extensive substrate adaptability and great potential of Y. lipolytica. By feeding concentrated MFW hydrolysate, SA titer up to 71.6 g/L was achieved from fed-batch fermentation with pH decreased naturally to 2.8. Finally, with the revised recovery method, 68.3% of the total SA with purity between 89.5% and 91.0% was recovered from the acidic fermentation broth with only low input of acid for acidification, which demonstrated the great advantages of SA production at low pH over that under neutral conditions in terms of economic improvement and environmental sustainability. In general, this study overcomes one of the major economic drawbacks for future feasible large-scale fermentative SA production, and it also illustrates a promising prospective for bio-SA production. [ABSTRACT FROM AUTHOR]

• A critical review on the microalgae bio-refinery process synthesis via superstructure optimization. • The possible future research plans based on the research gaps were recommended. • Considering different feedstocks and products in superstructure is a good topic for future studies. • Development of the efficient exact or hybrid solution algorithms is a good subject for future studies. • Development of quantitative methods for analyzing the social aspects is a good topic for future studies. Microalgae have numerous potential advantages as feedstock in producing biofuels and other value-added end products. The variety in processing pathways for biofuel production is one of the main challenges in commercializing microalgae-based bio-refineries. The superstructure optimization method is a great solution to overcome this challenge and attracted much attention in the academic communities. In the present study, a systematic review of past studies has been carried out to determine the future perspective in the microalgae-based bio-refinery process synthesis area of study with an emphasis on the superstructure optimization approach. In this regard, the relevant papers published from 2011 to 2022 are taken from the literature and categorized based on different classifications such as their feedstocks and end products, mathematical model, model characteristics including uncertainty, objective function, sustainability, solution method, and economic and environmental analysis. Then, the existing research gaps in the literature have been described to specify future research directions. [ABSTRACT FROM AUTHOR]

A multistage process was employed to obtain value-added products from brewer's spent grain (BSG). This paper is focused on the production and characterisation of cellulose nano-fibres (CNF) as one of the products obtained during the complete process. In the first stage, protein-rich liquor was separated via the alkaline (NaOH) treatment of dried BSG and stored for further utilisation. In the second stage, bleaching treatments were conducted to separate cellulose, which was later converted to CNF by high-pressure homogenisation. The lignocellulosic product from each step was analysed for its chemical composition by means of alkaline hydrolysis combined with the HPEAC method. The thermal properties were measured using thermogravimetric analysis (TGA). The morphology was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). X-ray diffraction (XRD) was done to observe changes in crystallinity. The nano-cellulose produced can be regarded as a value-added material from the bio-refinery of BSG along with numerous already-reported products. [ABSTRACT FROM AUTHOR]

Abstract: Black liquor gasification (BLG) for bio-fuel or electricity production at the modern pulp mills is a field in continuous evolution and the efforts are considerably driven by the climate change, fuel security, and renewable energy. This paper evaluates and compares two BLG systems for methanol production: (i) oxygen blown pressurized thermal BLG; and (ii) dry BLG with direct causticization, which have been regarded as the most potential technology candidates for the future deployment. A key objective is to assess integration possibilities of BLG technologies with the reference Kraft pulp mill producing 1000air dried tonnes (ADt) pulp/day replacing conventional recovery cycle. The study was performed to compare the systems’ performance in terms of potential methanol production, energy efficiency, and potential CO2 reductions. The results indicate larger potential of black liquor conversion to methanol from the pressurized BLG system (about 77million tonnes/year of methanol) than the dry BLG system (about 30million tonnes/year of methanol) utilizing identical amount of black liquor available worldwide (220million tDS/year). The potential CO2 emissions reduction from the transport sector is substantially higher in pressurized BLG system (117million tonnes/year CO2 reductions) as compared to dry BLG system (45million tonnes/year CO2 reductions). However, the dry BLG system with direct causticization shows better results when considering consequences of additional biomass import. In addition, comparison of methanol production via BLG with other bio-refinery products, e.g. hydrogen, dimethyl ether (DME) and bio-methane, has also been discussed. [Copyright &y& Elsevier]

Glycerol is a by-product of biodiesel, soap and fatty acid manufacturing plants, which are now facing sustainability threats and a reduction in prices in the market due to its oversupply as a result of the rapid expansion of biodiesel plants all over the world. The global production and consumption of glycerol, as well as demand and supply, are evaluated here. Glycerol offers a wide range of new opportunities based on its transformation in many applications due to its unique properties, renewability and availability in the current market. This paper is a comprehensive review of the utilization of glycerol as a value-added commodity, including in the synthesis of chemicals, in the production of hydrogen gas, as a fuel additive, as a fermentation substrate, in the co-pyrolysis and co-gasification of glycerol, in methanol production, in the development of fuel cells, in wastewater treatment and in many other applications. In the future, glycerol definitely will become a promising renewable feedstock in biorefineries to synthesize fuel, chemicals and power. [ABSTRACT FROM AUTHOR]

Food chain-based waste is generated in tonnes globally and this has led to release of greenhouse gases, poor air quality, land and water pollution. Food wastes are generated in tremendous quantity globally from local producer to international consumers and traders. Authors have used systematic literature review to identify the research gaps, thematic areas, methodology, sustainable techniques and future directions of processing food supply chain waste. Research is focused towards utilization of food waste as source for recovery of value-added compounds through sustainable technologies. Food waste can be utilized to synthesis platform chemicals, nutraceuticals, sugars, bio-fuels, bio-gas and bio-char via thermo-chemical conversion, anaerobic digestion and fermentation processes. This paper summarizes and provides technical insights on achieving circular bio-economy via technological advances in food waste processing for enhanced recovery of value-added compounds and future industrial scale operations. The state of art perspectives of food waste valorization and market outlook of platform chemicals and other products provides profitable economy for the food waste generator. Food security requires holistic approaches for effective usage of resources with inter linked global policies. [ABSTRACT FROM AUTHOR]

Sugarcane is a cash crop that has been a significant source of revenue in many countries around the world. In the last few decades, sugarcane mills that were only intended for sugar production were converted into biorefineries. Biorefinery enables the co-production of useful products from the sugarcane wastes such as bagasse, molasses, cane trash, filter mud and vinasse. In certain applications like disposable plates, fly ash, and as reinforcement in polymer composites, bagasse can be directly employed without the need for secondary processing while applications like paper, biochemical, lignosulfonate, vanillin, etc., require secondary processing through the biochemical route involving pre-treatment, acid hydrolysis, and fermentation. Other sugarcane wastes can also be mixed with bagasse to obtain biomethane, bioethanol, and bioelectricity. This article focuses on the recent advancements in such pre-treatment and processing methods employed by the researchers. It also outlines the strategies to co-generate two different products and ways to maximize the product yield and highlights various parameters influencing the process. The challenges that are critical to the sustainability of the sugarcane biorefineries and their mitigations were also discussed. [ABSTRACT FROM AUTHOR]

The idea of doubling the farmers' income in next 5 years has been slated by the Government of India. The specific target of increasing sugarcane farmers' income could be achieved by developing cost-effective technologies, transferring them from laboratory to land, educating the farmers and creating a linkage between all stakeholders. Consistent efforts shall be required to harness all possible sources for increasing farmer's income in and outside the agriculture sector with respect to improvement in sugarcane and sugar productivity, enhancement in resource use efficiency and adopting various other ways and means including intercropping, management of pests and diseases, use of biotechnological tools and minimizing post-harvest deterioration. The advances in sugarcane biotechnology could become remarkable in the coming years, both in terms of improving productivity as well as increasing the value and utility of this crop substantially. In future, genetically modified sugarcane varieties with increased resistance to different biotic and abiotic stresses would serve more towards sugarcane crop improvement. Any possibility of enhancement in the income of sugarcane farmers shall also be dependent upon the profitability and sustainability of the sugar industry. Integration of sugarcane production technologies for improvement in farm productivity, diversified sugarcane production system, reduced cost of cultivation along with increased processing plant efficiency and diversification to produce value added products shall ensure smooth and higher payment to the farmers. Development of low-cost technologies to convert "waste to resource" on a smaller scale shall also help the farmers to increase their income further. This paper focuses on possible measures to be taken up in each aspects of sugarcane cultivation including biotechnological approaches to achieve the goal of enhancing the income of sugarcane farmers substantially, particularly in the sub-tropical region of India. [ABSTRACT FROM AUTHOR]