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During the construction of smart grids, due to technological limitations, traditional sequential control systems have been unable to meet the needs of grid operation, exposing problems such as single control methods and functions, low operational efficiency, inability to independently complete complex tasks, and poor anti-interference ability, which in turn affect the power supply quality and operational stability of the grid, and fail to truly achieve the reliability, safety, and reliability of smart grids Economic and efficient goals. For this purpose, the author describes an adaptive intelligent control method for an integrated biomass energy heat conversion system consisting of more than one suction biomass gasifier, biomass gas burner, and steam boiler. The system uses PLC as a tool and takes the boiler outlet steam pressure as the control parameter. Based on the changes in the boiler outlet steam pressure, it automatically adjusts the feed and gas production of the gasifier, and subsequently adjusts the air supply of the burner. Ultimately, it achieves the goal of automatically adjusting the boiler heating volume with changes in steam pressure. The integrated heating and adaptive intelligent control system based on biomass gasification has been reliably verified in industrial applications. [ABSTRACT FROM AUTHOR]

The conversion of biomass energy sources is a crucial direction in the transformation of energy resources, such as cellulose to high-value chemicals. As an important platform compound, 5-hydroxymethylfurfural (HMF) is one of the worthwhile products from biomass. Previously, the use of Hf/ZSM-5 catalyst demonstrated excellent catalytic performance, with the yield of HMF reaching 67.50% under optimal reaction conditions (120 min, 190 °C, H2O(NaCl)/THF). Based on the previous work, the effect of a series of metal salts on the preparation of HMF from cellulose catalyzed by Hf/ZSM-5 catalyst was investigated in this paper. This result demonstrates the addition of AlCl3 promoted the production of HMF yield and AlCl3 completed with excellent performance among five metal salts. Moreover, the yield of HMF was improved to 70.95% by adjusting the optimal reaction conditions. [ABSTRACT FROM AUTHOR]

Bamboo has been identified as a promising solution to the energy crisis and climate change as a source of biomass energy. Due to its rapid growth and high‐value products, bamboo is considered as a potential source of biomass energy. Bamboo contains a significant amount of cellulose and hemicellulose, which can be converted to sugar constituents, making it an ideal raw material for energy production. This article reviews the different processes of producing bioethanol, biogas, biochar, and bio‐oil from bamboo biomass using techniques such as pyrolysis, hydrothermal liquefaction, fermentation, and anaerobic digestion, and discusses the opportunities and challenges of these conversion technologies. It also reviews the main types and morphological characteristics of energy bamboo species and proposes an evaluation system for energy bamboo species, which optimizes the utilization efficiency of bamboo biomass energy and maximizes benefits by adopting appropriate methods for producing bioenergy based on the characteristics of different bamboo species. [ABSTRACT FROM AUTHOR]

Biomass energy has drawn increased attention owing to its zero carbon emissions and large reserves. Pyrolysis instead of direct combustion is an efficient and clean way for biomass energy conversion. As a strong radiative species, H 2 O greatly affects the combustion processes. Despite the large concentration and fluctuation of H 2 O content in biomass pyrolysis gases (py-gas), radiation reabsorption effect has not been systematically investigated for py-gas combustion. In this study, one-dimensional simulations of premixed py-gas/air flames were conducted, using PREMIX code with both adiabatic and radiative models. The effects of H 2 O content and radiation reabsorption were examined. As H 2 O content in the py-gas mixture increased from 40% to 50%, the flame speeds decreased from 42.86 to 28.08 cm/s, while the relative differences caused by radiation reabsorption increased from 9.92% to 17.42%. Radiation reabsorption affected laminar flame speed primarily through the preheat-induced chemical effect, which was mainly controlled by HCO radical. The outlet mole fraction of NO was reduced by up to 13.56% when radiation reabsorption was considered. Reaction pathway analyses revealed that the NO emission was closely related to the outlet temperature and the peak NCO concentration, which were the limiting factors for the thermal-NO route and the fuel-NO route, respectively. [ABSTRACT FROM AUTHOR]

Owing to the high efficiency and specificity in moderate conditions, enzymatic biofuel cells (EBFCs) have gained significant interest as a promising energy source for wearable devices. However, the instability of the bioelectrode and the lack of efficient electrical communication between the enzymes and electrodes are the main obstacles. Herein, defect-enriched 3D graphene nanoribbons (GNRs) frameworks are fabricated by unzipping multiwall carbon nanotubes, followed by thermal annealing. It is found that defective carbon shows stronger adsorption energy towards the polar mediators than the pristine carbon, which is beneficial to improving the stability of the bioelectrodes. Consequently, the EBFCs equipped with the GNRs exhibit a significantly enhanced bioelectrocatalytic performance and operational stability, delivering an open-circuit voltage and power density of 0.62 V, 70.7 μW/cm2, and 0.58 V, 18.6 μW/cm2 in phosphate buffer solution and artificial tear, respectively, which represent the high levels among the reported literature. This work provides a design principle according to which defective carbon materials could be more suitable for the immobilization of biocatalytic components in the application of EBFCs. [ABSTRACT FROM AUTHOR]

This article presents current directions and methods of modernization of the energy sector using biofuel as an environmentally sustainable and sustainable energy source. At the beginning of the article, a generalized description of the problem of dependence of many countries on traditional petroleum fuels and its impact on energy security is given. The article analyzes the results of scientific research on the use of biofuels for diesel generators, including efficiency, pollutant emissions, mechanical problems, economic feasibility and its impact on agriculture. Further, the article offers specific directions for the modernization of the energy sector, in particular, the optimization of diesel engine settings and fuel mixtures to achieve optimal efficiency and reduce emissions. The prospects of using biofuels in combination with other alternative energy sources, such as sunflower energy and wind energy, are also highlighted. The use of traditional petroleum fuels in the energy sector is accompanied by problems of import dependence and harmful effects on the environment. In this regard, the article examines the current approach to the modernization of the energy sector using biofuel as an environmentally sustainable and sustainable energy source. First, the article briefly characterizes the problem of dependence of many countries on imported petroleum fuels, highlights the negative consequences of this phenomenon for energy security and economic stability. Next, the results of scientific research on the use of biofuel for diesel generators are analyzed. The authors pay attention to the efficiency of biofuel use, emissions of pollutants, possible mechanical problems and the economic feasibility of its use. In addition, the article draws attention to the importance of creating an appropriate infrastructure for the production, storage and supply of biofuel, as well as the development of innovative technologies to increase the efficiency of its use. The general result of the study is the presentation of information and analysis that will help to take into account the advantages and challenges of using biofuels in the energy sector when forming energy modernization strategies in the context of sustainable development and reducing the impact on the environment. The proposed directions and methods will create a basis for the development of effective solutions in the field of energy, contributing to ensuring the sustainability and ecological purity of energy processes. [ABSTRACT FROM AUTHOR]

The use of algal biomass as a renewable source of energy is potentially promising. The literature on biofuels derived from Sargassum is limited compared to other macroalgae. The unusual seaweed bloom of Sargassum from 2011 to date can be caused by the following factors: eutrophication of the sea, climate change, and other oceanographic patterns. The atypical invasion has had great ecological and economic effects in the affected regions. Traditionally, Sargassum has been recovered from coasts and beaches for use as fertilizer, but new markets need to be found to exploit the large volumes produced by the seaweed influx and mitigate its impact. The biochemical composition of Sargassum biomass defines it as a potential feedstock for biofuel production. However, the high moisture and ash content constitute the limitations for the development of some energy extraction methods. On the other hand, the costs associated with the removal of high volumes of accumulated Sargassum from coasts and beaches, transportation, cleaning, and storage are relatively high. Therefore, the production of biofuels from Sargassum seaweed is still a technical, economic, and energy challenge. This review proposes a multifactorial approach to the potential use of Sargassum biomass as feedstock for energy production, especially by thermochemical conversion (combustion, gasification, pyrolysis, and hydrothermal liquefaction). The survey analyses the chemical composition, biomass productivity and coastal impact, energy output, thermochemical conversion processes, techno-economic challenges, and future perspectives. In addition, a Sargassum biomass biorefinery approach with a circular bioeconomy approach is proposed. [ABSTRACT FROM AUTHOR]

• The Fe-Ni 3 S 2 @NiFe-PBA/NF electrocatalyst is synthesized by a two-step method. • Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst can convert 100 % of HMF and achieve 97.1 % FDCA yield. • Doping of Fe facilitates the deprotonation of Ni2+-OH forming the active Ni3+-O. • The Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst shows robust stability after 10 cycles in HMFOR. The electrooxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) represents a promising avenue for generating value-added products derived from biomass. Nevertheless, the development of highly efficient electrocatalysts for HMF electrooxidation (HMFOR) remains an ongoing challenge. In this study, we present a novel approach wherein Fe-doped Ni 3 S 2 @NiFe-PBA nanocubes are synthesized directly on three-dimensional nickel foam (NF) substrates using a straightforward hydrothermal reaction and subsequent impregnation. This composite Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst showcases exceptional performance in HMFOR (a faraday efficiency of 97.4 %), characterized by both its remarkable conversion (100 %) and impressive FDCA yield (97.1 %), coupled with its robust stability over ten cycles. The heightened HMFOR activity exhibited by the Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst can be contributed to the introduction of Fe into the Ni 3 S 2 matrix. This deliberate doping strategy engenders accelerated charge transfer kinetics, an increased abundance of accessible surface-active sites, and improved conductivity, thereby enhancing the overall HMFOR performance. By establishing these outcomes, this investigation lays a foundation for the prospective design of electrocatalysts with applications in biomass utilization and energy conversion. In this work, we synthesize Fe-Ni 3 S 2 @NiFe-PBA nanocubes on a Ni foam using a hydrothermal reaction and subsequent impregnation process. The introduction of Fe3+ into the Ni 3 S 2 matrix can increase the Ni3+/Ni2+ ratio, accelerated charge transfer kinetics, an increased abundance of accessible surface active sites, and improved conductivity, collectively enhancing the overall HMFOR performance. As a result, the Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst demonstrates the ability to convert 100 % of HMF at fixed 1.46 V vs RHE and achieve 97.1 % yield in FDCA generation, which is a 37 % higher than that of Ni 3 S 2 /NF. [Display omitted] [ABSTRACT FROM AUTHOR]

Marginal land conversion to perennial energy crops can provide biomass feedstocks and climate change mitigation. However, the effect of perennial energy crop cultivation on soil organic carbon (SOC) sequestration and its underlying mechanism in marginal land still remains incomplete. Here, SOC turnover, stability, and its potential sequestration were evaluated based on 10 years of land use change from C3 grass‐dominated marginal land to C4 energy crops Miscanthus and switchgrass cultivation. The naturally occurring 13C signature down to 60 cm depth was used to determine the energy crops‐derived C. Compared to reference marginal land, Miscanthus plantation increased the SOC stock at 0–60 cm depth by 17.8% and 64.3% in bulk and root zone, respectively. Similarly, the SOC stock under switchgrass was also 16.5% and 93.0% higher in bulk and root zone than in reference marginal land, respectively. The higher SOC stock in the root zone of switchgrass relative to Miscanthus was supported by the higher contribution of C4‐derived C to SOC (44.5% vs. 32.4%). The mean residence time of old C was higher under switchgrass than Miscanthus in the bulk zone across 0–60 cm (p < 0.05) but remained the same at 0–20 cm in the root zone. Specific SOC mineralization and temperature sensitivity were lower in soils under Miscanthus and switchgrass compared to reference marginal land. The partial least squares path model revealed that perennial energy crop cultivation enhances soil C stock via increased C4‐derived C input and reduced mineralization. In conclusion, marginal land conversion to perennial energy crops is a win–win strategy for C sequestration to mitigate climate change and support the growing bioenergy sector with biomass supply. [ABSTRACT FROM AUTHOR]

Biomass gasification technology under microwave irradiation is a new and novel method, and the energy conversion performances during the process play a guiding role in improving the energy conversion efficiencies and developing the gasification simulation models. In order to improve the energy utilization efficiency of microwave biomass gasification system, this study investigated and presented the energy conversion performances during biomass gasification process under microwave irradiation, and these were materialized through detailing (a) the energy conversion performance in the microwave heating stage, and (b) the energy conversion performance in the microwave assisted biomass gasification stage. Different forms of energies in the biomass microwave gasification process were calculated by the method given in this study based on the experimental data. The results showed that the useful energy (energy in silicon carbide (SiC), 18.73 kJ) accounted for 31.22% of the total energy input (electrical energy, 60.00 kJ) in the heating stage, and the useful energy (energy in the products, 758.55 kJ) accounted for 63.41% of the total energy input (electrical and biomass energy, 1196.28 kJ) in the gasification stage. During the whole biomass gasification process under microwave irradiation, the useful energy output (energy in the products, 758.55 kJ) accounted for 60.38% of the total energy input (electrical and biomass energy, 1256.28 kJ), and the energy in the gas (523.40 kJ) product played a dominate role in product energy (758.55 kJ). The energy loss mainly included the heat loss in the gas flow (89.20 kJ), magnetron loss (191.80 kJ) and microwave dissipation loss (198.00 kJ), which accounted for 7.10%, 15.27% and 15.76% of the total energy, respectively. The contents detailed in this study not only presented the energy conversion performances during microwave assisted gasification process but also supplied important data for developing gasification simulation models. • Energy conversion performances of microwave biomass air gasification were detailed. • Effects of gasification temperature and SiC loading were investigated. • The useful energy output accounted for 60.38% of the total energy input. • Energy loss was mainly by magnetron (15.27%) and microwave dissipation (15.76%). [ABSTRACT FROM AUTHOR]

With the fast consumption of traditional fossil fuels and the urgent requirement for a low-carbon economy and sustainable development, supercapacitors are gaining more and more attention as a clean energy storage and conversion device. The research on electrode materials for supercapacitors has become a hot topic nowadays. An electrode material for a supercapacitor, comprising the ZIF-67 in-built carbon-based material, was prepared from a biomass pre-hydrolysate via a hydrothermal process. As a by-product of dissolving slurry, the pre-hydrolysate is rich in carbon, which is an excellent biomass resource. The utilization of pre-hydrolysate to prepare carbon energy materials could realize the high value utilization of pre-hydrolysate and the efficient energy conversion of biomass. Meanwhile, the cobalt-based MOF (such as ZIF-67), as a porous crystalline material, has the advantages of having a regular order, high specific surface area and controllable pore size, as well as good thermal and chemical stability. The addition of ZIF-67 modified the morphology and pore structure of the carbon, and the obtained samples showed outstanding electrochemical performance. One- and two-step synthetic processes generated specimens with a coral-like cross-linked structure and a new type of rough, hollow, dandelion-like structure, respectively, and the pore size was in the range of 2.0–5.0 nm, which is conducive to ion transport and charge transfer. In C2-ZIF-67, the hollow structures could effectively prevent the accumulation of the electrochemical active center, which could provide enough space for the shrinkage and expansion of particles to protect them from the interference of electrolytes and the formation of solid electrolyte interphase film layers. Additionally, the plush tentacle structure with low density and a large specific surface area could expose more active sites and a large electrolyte electrode contact area, and short electron and charge transport paths. Importantly, active, free electrons of small amounts of Co-MOF (1 wt%) could be stored and released through the redox reaction, further improving the electrical conductivity of Carbon-ZIF-67 materials in this work. Consequently, C2-ZIF-67 exhibited superior specific capacitance (400 F g−1, at 0.5 A g−1) and stability (90%, after 10,000 cycles). [ABSTRACT FROM AUTHOR]

In this work, nitrogen‐doped porous carbons (NDPCs) were prepared by one‐step carbonization of biomass using Sargassum thunbergii as a model for energy storage, electroanalysis, and metal ion removal. The pore structures of NDPCs can be adjusted by changing the pyrolysis temperature (600–800 °C). It was discovered that NDPCs‐700 as a supercapacitor electrode material could display acceptable specific capacitance of 177 F g−1 in 6 M KOH aqueous electrolyte at current density of 0.2 A g−1 with good cycling stability (capacitance retention of 95 % after 2000 cycles), owing to its unique micro‐meso hierarchical pore structure, good conductivity and high nitrogen content (4.61 %). Also, it could act as an electrochemical sensing material, showing good electrocatalytic performance for dopamine (DA) detection in the dynamic detection range of 1.0 to 120 μM with a detection limit of 0.382 μM. Besides, the so fabricated multifunctional material can allow for the removal of metal ions like Hg2+ with high efficiency. [ABSTRACT FROM AUTHOR]

The giant miscanthus (Miscanthus × giganteus) is one of the most essential energy plants. It also finds various alternative uses, including installing belts to prevent soil erosion. Biomass from such belts should be removed and rationally managed every year. The parameters of miscanthus biomass were investigated in terms of its suitability for combustion and anaerobic fermentation. Under the conditions of the experiment, miscanthus achieved a stable yield already in the second year of vegetation, mainly due to the high planting density. Energy parameters turned out to be typical for straw biomass (calorific value 18.06 MJ/kg). Relatively low ash melting temperatures (<1400 °C) and their chemical composition meant a high risk of contamination depositing on heating devices, which is often indicated as a shortcoming of biomass compared to hard coal. Miscanthus silage can be a valuable substrate for anaerobic digestion, but it requires a sufficiently early harvest, which affects the yield of biomass. The yield of energy in biomass obtained after drying plants was 163,623.6 MJ/ha. In contrast, the yield of energy from biomass collected in summer and processed into biomethane was much lower and amounted to 72,978.2 MJ/ha. [ABSTRACT FROM AUTHOR]

For most traditional energy sources, price increases are a current perspective; on the other hand, conventional fuels are considered responsible for global warming, with very negative estimated consequences. For these reasons, the use of more environmentally friendly energy sources, from the category of renewable sources, is required for the next period. The article presents a part of a system designed to obtain domestic hot water by combining 2 renewable sources: solar energy and biomass energy. For the conversion of energy from biomass, tests were performed in 2 constructive variants, in order to improve the performances. [ABSTRACT FROM AUTHOR]

With the gradual increase in the consumption of non-renewable energy sources, the development of energy storage and conversion devices has become increasingly important. Sustainable self-supporting conductive collectors have become one of the effective ways to enhance the performance of energy storage devices. In this study, the pore modulation technique was implemented on Beijing poplar and camphor pine using delignification and water extraction, and six wood-derived carbon (WC) electrodes were prepared by heat treatment using untreated material as a control. By observing the microscopic morphology, it was found that all six carbon materials retained the graded porous structure characteristic of natural wood. The carbon material prepared from water extraction treated Beijing poplar (WPC) had the best capacitive properties. The conductive reduced graphene oxide (RGO) is composited with WPC, and the constructed RGO@WPC (RWPC) conductive collector has an average conductivity as high as 15.4 S m−1, which provides a strong guarantee for fast electron transport. The specific capacitance of RWPC is as high as 2100 mF cm−2 when the current density is 1 mA cm−2. The constructed RWPC//RWPC energy storage device has a maximum energy density of 3.76 Wh kg−1 and a maximum power density of 171.3 W kg−1. In this paper, a green and efficient self-supporting conductive collector with a graded porous structure is proposed. It also broadens the high value-added utilization of wood in energy storage. [Display omitted] • By regulating the porous structure of wood, the WPC has the best capacitive performance (1740.1 mF cm−2 at 1 mA cm−2). • Successfully constructed high-performance RWPC conductive collector (average conductivity of 15.4 S m−1, specific capacitance of 2100 mF cm−2). • This paper provides a high-performance self-supporting conductive collector for the development of biomass energy storage devices, which will help to realize more renewable energy storage electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of PP addition and torrefaction on fungus bran biochar was investigated. • The optimized hybrid biomass exhibited favorable characteristics for pelleting. • PP addition and torrefaction improved combustion index and activation energy. • An ideal biofuel was presented for energy conversion of plastic waste and biomass. This study explored the combustion behavior of co-torrefied biofuel derived from a novel combination of hybrid biomass and plastic waste. With the advanced thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR), the effect of waste polypropylene (PP) addition and co-torrefaction pretreatment on the combustion characteristics, reactivity, gaseous product release, and pelletization characteristics of Ca-rich fungus bran (FB) biofuel were systemically investigated. Notably, the presence of PP not only expedited the ignition process but also enhanced the combustion efficiency of the biofuel. In comparison, the co-torrefied hybrid biofuel demonstrated enhanced energy yields, with significant reductions in activation energy, highlighting its potential as an efficient energy source. Torrefaction enriched the biochar structure and led to improved combustion efficiency and a faster burnout rate. Additionally, the torrefaction process also increased biomass calcium content, which resulted in the effective reduction of sulfur dioxide (SO 2) emissions. The incorporation of PP also demonstrated superior biomass binding capabilities and amplified pellet quality, when combined with co-torrefaction. Overall, this research underscored the viability of PP as a complementary fuel for FB. When co-torrefied, the resultant hybrid biofuel not only offered enhanced combustion efficiency but also presented an eco-friendly solution, minimizing SO 2 emissions and acidic rain potential. This research, therefore, heralded an innovative path towards producing superior quality biomass pellets, minimizing storage and transportation costs, and optimizing energy conversion. [ABSTRACT FROM AUTHOR]

Carbohydrate-binding module (CBM) family 91 is a novel module primarily associated with glycoside hydrolase (GH) family 43 enzymes. However, our current understanding of its function remains limited. PphXyl43B is a β -xylosidase/ α -L-arabinofuranosidase bifunctional enzyme from physcomitrellae patens XB belonging to the GH43_11 subfamily and containing CBM91 at its C terminus. To fully elucidate the contributions of the CBM91 module, the truncated proteins consisting only the GH43_11 catalytic module (rPphXyl43B-dCBM91) and only the CBM91 module (rCBM91) of PphXyl43B were constructed, respectively. The result showed that rPphXyl43B-dCBM91 completely lost hydrolysis activity against both p -nitrophenyl- β -D-xylopyranoside and p -nitrophenyl- α -L-arabinofuranoside; it also exhibited significantly reduced activity towards xylobiose, xylotriose, oat spelt xylan and corncob xylan compared to the control. Thus, the CBM91 module is crucial for the β -xylosidase/ α -L-arabinofuranosidase activities in PphXyl43B. However, rCBM91 did not exhibit any binding capability towards corncob xylan. Structural analysis indicated that CBM91 of PphXyl43B might adopt a loop conformation (residues 496–511: ILSDDYVVQSYGGFFT) to actively contribute to the catalytic pocket formation rather than substrate binding capability. This study provides important insights into understanding the function of CBM91 and can be used as a reference for analyzing the action mechanism of GH43_11 enzymes and their application in biomass energy conversion. • PphXyl43B belongs to GH43_11 subfamily with CBM91 module at its C terminus. • The CBM91 module is crucial for the bifunctional enzymatic activities of PphXyl43B. • CBM9I in PphXyl43B has low affinity for insoluble BWX and cannot bind soluble CCX. • The enhancement effect of CBM91 on PphXyl43B depends on its unique loop conformation. [ABSTRACT FROM AUTHOR]

Attempts to find and quantify the supposed low entropy of organisms and its preservation are revised. The absolute entropy of the mixed components of non-living biomass (approximately −1.6 × 103 J K−1 L−1) is the reference to which other entropy decreases would be ascribed to life. The compartmentation of metabolites and the departure from the equilibrium of metabolic reactions account for reductions in entropy of 1 and 40–50 J K−1 L−1, respectively, and, though small, are distinctive features of living tissues. DNA and proteins do not supply significant decreases in thermodynamic entropy, but their low informational entropy is relevant for life and its evolution. No other living feature contributes significantly to the low entropy associated with life. The photosynthetic conversion of radiant energy to biomass energy accounts for most entropy (2.8 × 105 J K−1 carbon kg−1) produced by living beings. The comparatively very low entropy produced in other processes (approximately 4.8 × 102 J K−1 L−1 day−1 in the human body) must be rapidly exported outside as heat to preserve low entropy decreases due to compartmentation and non-equilibrium metabolism. Enzymes and genes are described, whose control minimizes the rate of production of entropy and could explain selective pressures in biological evolution and the rapid proliferation of cancer cells. [ABSTRACT FROM AUTHOR]

Formic acid is one of the key components in green chemistry being involved in energy storage, production of chemical intermediates and fuel components. Therefore the knowledge of its stability is of crucial importance and a systematic study of its decomposition is needed. The kinetics of formic acid decomposition to hydrogen and carbon dioxide was investigated in a laboratory-scale fixed bed reactor at 150–225 °C and atmospheric pressure. Palladium nanoparticles deposited on porous active carbon Sibunit were used as the heterogeneous catalyst. The catalyst was characterized by nitrogen physisorption and high-resolution transmission electron microscopy. The average palladium nanoparticle size was 5–6 nm. The impacts of mass transfer resistance and formic acid dimerization were negligible under the reaction conditions. Prolonged experiments revealed that the catalyst had a good stability. Hydrogen and carbon dioxide were the absolutely dominant reaction products, whereas the amounts of carbon monoxide and water were negligible. The experimental data were described with three kinetic models: first order kinetics, two-step adsorption-reaction model and multistep adsorption-decomposition model of formic acid. The multistep model gave the best description of the data. [Display omitted] • Formic acid is very important molecule in large-scale production, biomass conversion and energy storage • Catalytic decomposition of formic acid was studied from kinetic, mass transfer and reactor perspectives • A model for the decomposition process in a fixed bed reactor was developed • The model gave a good description of experimental data [ABSTRACT FROM AUTHOR]

Summary: Using renewable microalgal biomass as active feedstocks for biofuels and bioproducts is explored to substitute petroleum‐based fuels and chemicals. In the last few years, the importance of microalgae biomass has been realized as a renewable feedstock due to several positive attributes associated with it. Biorefinery via anaerobic digestion (AD) of microalgal biomass is a promising and sustainable method to produce value‐added chemicals, edible products and biofuels. Microalgal biomass pretreatment is a significant process to enhance methane production by AD. Findings on the AD microbial community's variety and organization can give novel in turn on digester steadiness and presentation. This review presents a vital study of the existing facts on the AD microbial community and AD production. Co‐digestion of microalgal biomass with different co‐substrates was used in AD to enhance biogas production, and the process was economically viable with improved biodegradability. Microcystins, which are produced by toxic cyanobacterial blooms, create a severe hazard to environmental health. Anaerobic biodegradation is an effective method to degrade the microcystins and convert into nontoxic products. However, for the cost‐effective conversion of biomass to energy and other beneficial byproducts, additional highly developed research is still required for large‐scale AD of microalgal biomass. [ABSTRACT FROM AUTHOR]

At European level, Directive 2018/2001 / EU on energy from renewable sources is the legal framework for its development in all sectors of the EU economy. Among the other sources, biomass for energy (bioenergy) continues to occupy a leading place in the EU, with a share of almost 60%. Biomass energy can be used for heating, electricity and transport fuels, contributing to economic growth, job creation and reducing greenhouse gas emissions. Biomass production takes place from the growth of raw materials to the final conversion of energy, but ultimately renewable energy in biomass must meet the sustainability criteria. At present, sustainability criteria are regulated for agricultural biomass that does not have to come from forests with high forest biodiversity. The process of producing pellets consists of subjecting the very fine dry biomass to high pressures and temperatures, and the compression is done through a hole of a few millimeters where small cylinders are produced which are cut to the desired length and then cooled. The pellets have a cylindrical shape, with a diameter between 6-10 mm and 10-30 mm in length, are easy to handle, represent a dense fuel in energy (650 kg / m3 bulk density), and the use of local resources in the production of pellets makes a concrete contribution to environmental change. [ABSTRACT FROM AUTHOR]

Algae have gained substantial importance as the most promising potential green fuel source across the globe and is on growing demand due to their antioxidant, anticancer, antiviral, antihypertensive, cholesterol reducing and thickening properties. Therefore, it has vast range of application in medicines, pharmaceutical, cosmetics, paper and nutraceutical industries. In this work, the remarkable ability of algae to convert CO2 and other toxic compounds in atmosphere to potential biofuels, foods, feeds and high-value bioactive compounds is reviewed. Algae produce approximately 50% of the earth's oxygen using its photosynthetic activity, thus acting as a potent tool to mitigate the effects of air pollution. Further, the applicability of algae as a desirable energy source has also been discussed, as they have the potential to serve as an effective alternative to intermittent renewable energy; and also, to combustion-based fossil fuel energy, making them effective for advanced biofuel conversions. This work also evaluates the current applications of algae and the implications of it as a potential substrate for bioplastic, natural alternative to inks and for making paper besides high-value products. In addition, the scope for integrated biorefinery approach is also briefly explored in terms of economic aspects at the industrial scale, as such energy conversion mechanisms are directly linked with sustainability, thus providing a positive overall energy outlook. [ABSTRACT FROM AUTHOR]

Bangladesh has encountered several challenges, including issues like overpopulation, energy shortage, and global warming for the last few decades. Addressing the increasing energy demand has become a crucial concern because of rapid increase in population and lack of growth in the economic. The electricity production of a country heavily relies on fossil fuels, particularly natural gas, which makes up approximately 54% of the current installed capacity. Bangladesh is an agrarian nation and biomass stands out as a source of renewable energy having significant potential to mitigate the demand for heat and electricity. Biomass resources in the country mainly comprise animal dung, agricultural crop residuals, solid waste from municipalities and forest residues. The existing biomass resources contribute to producing a high amount of energy and content of around 1574.16 PJ of energy equivalent to 437.28 TWh of electricity in which agricultural residues, animal manure, municipal solid waste, and forest residues impart around 852.32 PJ, 399.04 PJ, 112.16 PJ, and 210.64 PJ of energy respectively. This paper explores the extent, possibilities, and technologies associated with biomass energy conversion. Additionally, the study delves into the several biomass projects that the government, as well as non-governmental groups, are working on for environmental sustainability along with plans, challenges, and methods that are being utilized to encourage biomass technologies across Bangladesh. [Display omitted] • The biomass potentiality in Bangladesh for heat and electricity generation is emphasized. • The energy scenario and necessity of alternative energy sources in Bangladesh are discussed. • The available energy conversion technologies from biomass in Bangladesh are presented. • The existing biomass resource content of around 1574.16 PJ (437.28 TWh of electricity) of energy. • The economic aspects and challenges of biomass conversion into energy are discussed. [ABSTRACT FROM AUTHOR]

Temer musa (Prosopis chilensis) is an invasive wild tree found in the desert of many countries, e.g., Eritrea, Ethiopia, Sudan, India, South Africa, and the USA. The thermochemical properties of this invasive tree were analyzed as a potential biomass feedstock for energy generation. The calorific value measurement of the temer musa wood was found to be 19.83 MJ/kg. Thermogravimetric analysis and derivative weight profiles displayed that the decomposition happened in four stages representing moisture content, volatile matter, fixed carbon, and ash formation. The proximate parameters are in good range with other known biomasses and are found suitable for the thermochemical energy conversion. The gasification process confirmed the existence of several gases that are usually observed in invasive biomasses. All gasification gases were in the acceptable range, and no hydrogen sulfide gas was observed, which makes the conversion as environment friendly. The obtained results show that the energy conversion of temer musa is suitable for real-time implementation. [ABSTRACT FROM AUTHOR]

Artificial neural networks were used for the prediction of three biomass ash fusion temperatures: initial deformation temperature IDT, hemispherical temperature HT and flow temperature FT based on chemical composition of the ash. Applicability of 400 neural network configurations (of linear, MLP, RBF and GRNN types) was verified statistically. Multilayer perceptron with 12 inputs representing fractions of the ash compounds, 11 hidden neurons and three outputs (IDT, HT, FT) proved to be the optimal neural model configuration. Statistical analysis suggested also, that considering intrinsic dispersion within the raw experimental data (literature data supplemented with the authors' own results describing the halloysite addition effect), quality of the resulting 3-output IDT-HT-FT model (IDT prediction with R 2 0.615, HT with R 2 0.756 and FT with R 2 0.729) could be regarded satisfactory for the identification and generalization of the discussed relationships. Analysis of the neural model sensitivity in respect to the input variables demonstrated, that the most important factors affecting all ash transition temperatures in the 3-output IDT-HT-FT model were: K 2 O, SiO 2 , CaO and Al 2 O 3 fractions. Moreover, individual sensitivity in respect to IDT, HT and FT temperatures slightly varied (characteristics provided by independently established 1-output networks – IDT model, HT model and FT model, respectively). Statistically verified neural network working as the 3-output IDT-HT-FT model can be applied in various computational tasks in biofuels energy sector required by Industry 4.0 principles, as well as in the selected Circular Economy problems. • Chemical compositions of the ashes were correlated with their melting temperatures. • Ash melting temperatures can be effectively predicted by neural network model. • Predictions of neural models are more accurate compared to statistical models. • Sensitivity of each melting temperature in respect to ash components is different. • The results can improve the technologies of biomass energy conversion. [ABSTRACT FROM AUTHOR]

Aquatic biomass is promising due to its high productivity in less nutrient environment. Gasification is one of the frontier technologies to convert biomass into energy, mainly to produce electricity. Recent development in electrochemical technologies allows the utilization of electricity to upgrade waste CO 2 into chemical products. In the present study, the performance of integrated gasification and electrolyzer is evaluated. The gasification converts biomass into syngas and electricity, while the electrolyzer convert CO 2 from the gasification residue into chemicals such as CO and methanol by utilizing the electric power from the gasification. The variation of the gasifying agent flow rate (O 2 equivalence ratio between 0.36 and 1.00) provides the variation of syngas composition (H 2 : 28–65%; CO: 25–43%) and heating value (12–30 MJ/kg). The production of CO or methanol is significantly influenced by O 2 equivalence ratio and fraction of syngas into power generator. The highest exergy loss is found to be in the cooling system. The net CO 2 emission of the proposed configuration is negative (−0.09 to −0.17 kg CO 2 /GJ at O 2 equivalence ratio of 0.36) by considering the CO 2 consumption of the biomass feed. Therefore, this system is promising for further investigation as the future renewable technology for energy conversion. Image 1 • O 2 ER and SP influences syngas properties, CO 2 emission and exergy efficiency. • Electrolyzer product (MeOH or CO) affects CO 2 emission and exergy efficiency. • MeOH and CO production emits 0.09–0.16 and 0.08–0.11 tonCO 2 /GJ, respectively. • The highest energy production efficiency with MeOH and CO: 62 and 66%, respectively. • The highest exergy efficiency with MeOH and CO: 39% and 40%, respectively. [ABSTRACT FROM AUTHOR]

The incorporation of highly active but also highly sensitive catalysts (e.g. the [FeFe] hydrogenase from Desulfovibrio desulfuricans) in biofuel cells is still one of the major challenges in sustainable energy conversion. We report the fabrication of a dual‐gas diffusion electrode H2/O2 biofuel cell equipped with a [FeFe] hydrogenase/redox polymer‐based high‐current‐density H2‐oxidation bioanode. The bioanodes show benchmark current densities of around 14 mA cm−2 and the corresponding fuel cell tests exhibit a benchmark for a hydrogenase/redox polymer‐based biofuel cell with outstanding power densities of 5.4 mW cm−2 at 0.7 V cell voltage. Furthermore, the highly sensitive [FeFe] hydrogenase is protected against oxygen damage by the redox polymer and can function under 5 % O2. [ABSTRACT FROM AUTHOR]

Technologies for conversion of microbial energy have recently attracted interest to transform waste into bioenergy, thus addressing simultaneously environmental and energy issues. Nonetheless, actual microbial systems for energy conversion have limitations such as low rate of mass transfer, uneven energy distribution and strong inhibition of products and by-products. These technical bottlenecks can be alleviated by using membranes, which regulate the transfer of mass, heat and energy. Here we review applications of membranes for microbial energy conversion. We discuss mechanisms, functions and development of membranes for feedstock preparation, bioenergy production and bioproduct post-treatment. We present key membrane factors that control the efficiency of microbial fuel cells. We address membrane biofouling problems and anti-fouling approaches, in order to improve future commercialization. [ABSTRACT FROM AUTHOR]

Natural rubber‐based industries in Southern Thailand are generating concentrated latex sewage sludge (CLS), which is commonly managed by landfilling practice that is causing serious environmental hazards. The purpose of this study was to develop a method to produce pellets using CLS and para‐wood sawdust as a potential biomass source for energy generation. The process started with dewatering the CLS through a decanter centrifuge. Then a flat die pellet mill was applied for copelletization. Finally, the pellets were investigated to evaluate the higher heating value and toxic heavy metals (Cu, Zn, Cr, As, Cd, and Pb) using proximate ‐ ultimate analysis, fourier transform infrared analysis, scanning electron microscopy, calorific value, thermogravimetric analysis, atomic absorption spectrometer, and inductively coupled plasma optical emission spectroscopy. The results showed that the addition of the para‐wood sawdust resulted in higher heating value and lower ash content of 3,620 ± 12 kcal/kg and 4.93 ± 0.98%, respectively. Besides, it has increased the carbon content of the pellet from 28.23 to 46.26% highest among all the samples. Furthermore, the method developed in this study is not only environmentally friendly but also economically sound than the earlier management of CLS. [ABSTRACT FROM AUTHOR]

This article presents bio-oil production from Napier grass by using a pyrolysis process. The comparative potential of energy conversion and the cost of production among bio-oil, bio-ethanol, biogas and syngas from gasification by using Napier grass as raw material were also analyzed. The pyrolysis in this study was developed from previous work in order to improve the yield of bio-oils. The circulating fluidized bed reactor (CFBr) was used as the reactor, and a new scrub condenser was applied in order to increase the performance of condensing vapor into bio-oil. This system had the ability to feed Napier grass between 45-75 kg/hr, and it could create a solidrecirculating rate of about 52.36 kg/m²s at 7 m/s of maximum superficial velocity. From the results of the bio-oil production, it has been concluded that the maximum yield of bio-oil production is 44.60 wt% at a feed rate of 60 kg/hr and bed temperature of 480°C. The properties and chemical components of bio-oil were also determined. A comparison of energy conversion from Napier grass to products such as bio-oil, ethanol, biogas and syngas through the gasification process as well as an analysis of cost of production revealed that syngas production through gasification has a greater potential energy conversion and cost of production than other technology, which had an energy conversion efficiency and cost of production of about 72.65% and 0.26 USD/GJ, respectively. However, as compared to liquid fuel, the gas fuel has greater limitations in terms of utilization and transportation. The bio-oil production from pyrolysis in this study had a cold efficiency and cost of production of about 28.24% and 17.98 USD/GJ, which proved a more advantageous trend of cold efficiency and production cost than bio-ethanol production, thus it can support a large energy project to create more energy security. [ABSTRACT FROM AUTHOR]

In the paper, the authors suggest a way of assessing the level of availability of electricity that comes from renewable energy sources based on fuzzy logic. The modeling is done with the support of the Fuzzy Toolbox in the Matlab computer software. Based on the electricity level, decisions can be made to control the components of the sources so that the availability is increase. Thus the energy sources will operate optimally. The proposed model is applied in the paper for the following categories of renewable energy resources: biomass, hydraulic energy, photovoltaic solar energy and wind energy. [ABSTRACT FROM AUTHOR]

In the paper, the authors suggest a way of assessing the level of availability of electricity that comes from renewable energy sources based on fuzzy logic. The modeling is done with the support of the Fuzzy Toolbox in the Matlab computer software. Based on the electricity level, decisions can be made to control the components of the sources so that the availability is increase. Thus the energy sources will operate optimally. The proposed model is applied in the paper for the following categories of renewable energy resources: biomass, hydraulic energy, photovoltaic solar energy and wind energy. [ABSTRACT FROM AUTHOR]

Torrefaction is a thermal conversion method extensively used for improving the properties of biomass. Usually this process is conducted within a temperature range of 200-300 °C under an inert atmosphere with residence time up to 60 minutes. This work aimed to study the kinetic of thermal degradation of oil palm frond pellet (OPFP) as solid biofuel for bioenergy production. The kinetics of OPFP during torrefaction was studied using frequently used iso-conversional model fitting (Coats-Redfern (CR)) and integral model-free (Kissinger-Akahira-Sunose (KAS)) methods in order to provide effective apparent activation energy as a function of conversion. The thermal degradation experiments were conducted at four heating rates of 5, 10, 15, and 20 °C/min in a thermogravimetric analyzer (TGA) under non-oxidative atmosphere. The results revealed that thermal decomposition kinetics of OPFP during torrefaction is significantly influenced by the severity of torrefaction temperature. Via Coats-Redfern method, torrefaction degradation reaction mechanism follows that of reaction order with n = 1. The activation energy values were 239.03 kJ/mol and 109.28 kJ/mol based on KAS and CR models, respectively. [ABSTRACT FROM AUTHOR]

Summary: Although xylose is the secondary dominant sugar derived from biomass, the conversion of xylose to energy products is quite challenging. In this work, a new exoelectrogenic yeast strain (Cystobasidium slooffiae strain JSUX1) that can generate electricity in microbial fuel cell (MFC) by using xylose as the substrate was isolated and identified. After adaptation, it produced significant current output with rapid xylose metabolism. More surprisingly, this strain produced hydrogen gas either in anerobic flask incubation or in MFC, which delivered a 67 mW/m2 power output and 23 L/m3 hydrogen gas in MFC with xylose as fuel. Further electrochemical analysis indicated that riboflavin was secreted by this strain as the electron mediator for efficient electron transfer between cells and electrode in MFC. This is the first microorganism identified that can simultaneously produce bio‐hydrogen and bio‐electricity from xylose, which would diversify the toolbox of biomass energy. [ABSTRACT FROM AUTHOR]

Biofilm seems to be an ideal cultivation system for microalgae liquid biofuel conversion technologies due to the advantage of high biomass concentration. However, research on the biofilm cultivation system for microalgae liquid biofuel producing were limited. In this study, a life-cycle assessment was conducted for microalgae liquid biofuel production in this system via three conversion technologies: transesterification, hydrothermal liquefaction and pyrolysis. The result shows that scenario hydrothermal liquefaction seems to be the most feasible technology to produce liquid biofuel in biofilm system because only hydrothermal liquefaction achieved positive energy and environment benefits with a net energy ratio of 0.87 and Greenhouse gas emissions of −39.91 g CO 2-eq MJ−1. For transesterification and pyrolysis, the net energy ratio (2.18 and 2.06) were larger than 1, while Greenhouse gas emissions (3.28 and 59.25 g CO 2-eq) were greater than 0. This indicated that these scenarios exhibited negative energy and environment benefits due to heavy use of chemicals and high energy consumption during biomass drying process, respectively. Additionally, according to the sensitivity analysis, bio-crude mass yield exhibited a more significant impact on the energy and environment loads for scenario hydrothermal liquefaction than the other factors. • LCA of biofilm cultivation was conducted for microalgae liquid biofuel production. • Only scenario HTL achieved positive energy and environment benefits. • NER and GHG emissions of HTL were 0.87 and −39.91 g CO 2-eq MJ−1, respectively. • Bio-crude mass yield had the most profound impact on NER and GHG emissions for HTL. [ABSTRACT FROM AUTHOR]

In thermal energy conversion of biomass, the char conversion rate influences the design of industrial systems. Yet there is no consensus on the relative influences of O 2 , CO 2 and H 2 O on the char conversion rate. The present study aims at clarifying the roles of these oxidizers on biomass char conversion. Single particles of different particles sizes were oxidized in mixtures of O 2 /N 2 , CO 2 /N 2 , H 2 O/N 2 and O 2 /CO 2 /H 2 O/N 2 at various temperatures. The results show that for large particles and high temperatures, CO 2 and H 2 O gasification reactions play a dominant role, while for sufficiently small particles and low temperatures, the O 2 oxidation reaction plays a dominant role in mixtures of O 2 /CO 2 /H 2 O/N 2. Two different particle models were used to compute char conversions: a detailed single particle model, and a conventional particle model assuming that rates in mixtures of oxidizers can be predicted based on rates of single oxidizers. The results show that the char oxidation rates are strongly overestimated when predicting rates based on single oxidizers, while the detailed model shows a good agreement to the experimental measurements. • Biomass char oxidation model for the first time validated in mixtures of O 2 /CO 2 /H 2 O. • Influences of CO 2 and H 2 O on char conversion depend strongly on the particle size. • Biomass char conversion in O 2 /CO 2 /H 2 O/N 2 occurred more rapidly than in O 2 /N 2. • Rates cannot be predicted based on rates of single oxidizers. [ABSTRACT FROM AUTHOR]

Pyrolysis is one of the potential routes to harmless energy and useful chemicals from biomass. The pyrolysis of Albizia amara was studied for determining the main characteristics and quantities of liquid products. Particular investigated process variables were temperature from 350 to 550°C, particle size from 0.6 to 1.25 mm, and heating rate from 10 to 30 °C/min. The maximum bio-oil yield of 48.5 wt% at the pyrolysis temperature of 450°C was obtained at the particle size of 1.0 mm and at the heating rate of 30 °C/min. The bio-oil product was analyzed for physical, elemental, and chemical composition using Fourier transform infrared spectroscopy and gas chromatography spectroscopy. The bio-oil contains mostly phenols, alkanes, alkenes, saturated fatty acids and their derivatives. According to the experimental results, the pyrolysis bio-oil can be used as low-grade fuel having heating value of 18.63 MJ/kg and feedstock for chemical industries. [ABSTRACT FROM AUTHOR]

Abstract We introduced an innovative design of a cantilevered piezoelectric generator with airfoil-based structures for harvesting underutilized aeroelastic energy in the pneumatic system. The cantilevered piezoelectric generator is composed of a polyvinylidene fluoride layer and an airfoil baffle. The working mechanism and electric output performance are systematically investigated. By integrating into the pneumatic system, the airfoil-based cantilevered piezoelectric generator has been used for real-time energy storage. In order to improve the energy conversion efficiency of the generator, an air amplifier is added between the pneumatic system and the generator to increase the flow of air which is discharged from the pneumatic system. Compared with no air amplifier, the output voltage of the generator is increased to 3.48 times. The optimal output power can achieve 13.06 μW through the 7 MΩ resistor and under flow of 200 L/min. This work provides a way to improve the energy conversion efficiency of piezoelectric generators and may promote the development of piezoelectric generators in intelligent pneumatic system. This technology can also be extended for harvesting wind energy. [ABSTRACT FROM AUTHOR]

Abstract In order to reach the national target in the use of renewable energy in the transport sector, about 55% of the biodiesel consumed in Italy is imported. However, imported biofuel is currently debated since large-scale production has entailed different environmental and socioeconomic problems. Sustainability in biofuel production is a priority for the European Union and with the new Common Agricultural Policy 2014–2020 (CAP) this priority could become an opportunity through access to aids for the adoption of sustainable agricultural practices. Considering the importance to promote small-scale biofuel production, this study aimed to assess the economic feasibility of rapeseed straight vegetable oil (SVO) use as a self-supply agricultural biofuel in Italian context, assuming that rapeseed is cultivated by using practices of conservation agriculture. The financial support of the new CAP was considered, and alternative hypotheses were assumed to promote the SVO supply chains. The economic analysis shows that EU aids can help to promote inland biofuel production, ensuring positive profits for farmers (with a net present value up to 181 thousand €), thereby reducing the risk connected to investments, mainly due to the fluctuation of some key variables, like diesel price. Moreover, results highlight the importance of establishing farmers' associations: given the high cost of the initial investment, the absence of an agreement for the creation of an optimum-sized supply chains might make those investments non profitable. Agricultural policy is therefore helpful to promote sustainable biofuel production, making the supply chains independent and self-sufficient over time. In this context, to ensure a sustainable biofuel production, beside the provision of support to the initial investments, it is also important to consider in the future biofuel policy scenario the possibility to incentive energy crop cultivation by promoting conservation agricultural practices (e.g., crop diversification, crop rotation, minimum tillage). Highlights • An economic evaluation of the small-scale biofuel production was carried out. • Conservative agricultural practices were considered for energy crops. • The analysis show the cost-effectiveness of sustainable biofuel production. • The results highlight the importance of establishing farmers' associations. • An increase in the diesel price can make the supply chain self-sufficient over time. [ABSTRACT FROM AUTHOR]

Highlights • We reviewed algal biorefinery as a sustainable approach to valorize algal biomass. • Algal biomass processing at higher TRL level provide sustainability. • Sustainable biorefinery solutions provide value-added product recovery. • Biorefinery Complexity Index (BCI) is an important indicator to access risks. Abstract In recent years, ever-increasing socio-economic awareness, and negative impact of excessive petro consumption have redirected the research interests towards bio-resources such as algal-based biomass. In order to meet current bio-economy challenges to produce high-value multiple products at a time, new integrated processes in research and development are necessary. Though various strategies have been posited for conversion of algal-based biomass to fuel and fine chemicals, none of them has been proved as economically viable and energetically feasible. Therefore, a range of other bio-products needs to be pursued. In this context, the algal bio-refinery concept has appeared with notable solution to recover multiple products from a single operation process. Herein, an algal-based bio-refinery platform for fuel, food, and pharmaceuticals considering Bio-refinery Complexity Index (BCI) has been evaluated, as an indicator of techno-economic risks. This review presents recent developments on algal-biomass utilization for various value-added products as part of an integrated bio-refinery. [ABSTRACT FROM AUTHOR]

Abstract Biomass is vital for future energy use, but several disadvantages obstruct its commercial applications. Co-thermochemical conversions of biomass and fossil fuels are alternative methods for offsetting the disadvantages of biomass and improving the quality of bio-oil. This paper overviewed the state-of-the-art research and development of co-thermochemical conversions of biomass and fossil fuels (i.e., coal, oil sand and oil shale). Emphasis was placed on different types of feedstocks, three thermochemical conversion methods (i.e., co-pyrolysis, co-gasification and co-liquefaction) and the synergistic effects. Furthermore, the influencing factors, advantages and disadvantages, and the possible mechanisms related to these co-thermochemical conversion technologies are discussed. The current developments and prospects for co-thermochemical conversions of biomass and fossil fuels are also proposed. Graphical abstract fx1 Highlights • The co-thermochemical conversions of biomass and fossil fuels were discussed. • Synergistic effects regarding products compositions and yields were overviewed. • The possible mechanisms of synergistic effects studied before were summarized. • The prospects of co-thermochemical methods of biomass and fossil fuels are discussed. [ABSTRACT FROM AUTHOR]

Abstract With the growing shortage of fossil energy and the increasing of concerns over global climate changes and environmental problems have driven the development of alternative energy sources. Recently, great interest has been oriented towards the development of sustainable resources, especially the utilization of lignocellulosic biomass, a renewable and the most abundant source of biomass originating from plant photosynthesis in nature. Catalytic conversion of renewable cellulosic biomass can produce a series of compounds such as 5-hydroxymethylfurfural (HMF) and 2,5-dimethylfuran (DMF) which are important platform compounds and ideal renewable alternative to fossil fuels. To obtain the renowned bio-based platform molecules, various catalysts and reaction systems have been used in the past decade years. To fully understand current biomass to HMF and DMF development, it is necessary to have an overview and comparison of different homogeneous and heterogeneous catalysts. The reaction systems also exhibit a remarkable impact on the yield and distribution of products with different catalysts. General trends and future research directions of using biomass for HMF, DMF production are also discussed systematically. Graphical abstract fx1 Highlights • Shifting from fossil resources to sustainable biomass for chemicals production is important in both academic and our society. • A comprehensive review about the catalytic conversion of biomass into HMF and DMF have been presented. • Catalysts, and reaction systems for the production of HMF and DMF developed in the last few years are discussed. • The scale-up conversion of biomass and the process economy analysis of HMF and DMF production are also discussed. [ABSTRACT FROM AUTHOR]

Microalgae photobioreactors are among the most effective systems for capturing gaseous CO2, the main contributor to global warming. Their capacity to generate massive amounts of biomass has been exploited serendipitously to sequester CO2 and explicitly to remove nutrients from municipal wastewater. Unfortunately, research in this area has not included merging these dual capacities to address global warming. Instead, most are focused on thermolytic conversion of biomass into energy which in end returns CO2 to the atmosphere. In this study, we investigated the potential of combining the two microalgal capacities (that of deriving nutrients from municipal wastewater and metabolic carbon from atmospheric or industrial CO2 supplies), into an integrated means of reducing nutrients in ocean-bound wastewater and CO2 in the atmosphere simultaneously. The test species used in this study was Chlorella vulgaris (C. vulgaris); the turbidity of C. vulgaris was used as a measure of yield in biomass. Our results show (i) that an open photobioreactor, and not a closed one, is the most productive, especially when augmented with industrial CO2 (hence making a strong case for scrubbing CO2 gas from industrial sources), (ii) that a mechanically agitated C. vulgaris culture is more productive than a static one, (iii) that without mechanical agitation, 32 ± 3 days of incubation are needed to reach the maximum yield of an open photobioreactor, (iv) that the optimal proportion of wastewater (%WW) required to support C. vulgaris growth is 80 ± 3%; at least 33%WWis required to observe growth above background, and (v) that without intervention, the upper pH limit of a WW-based C. vulgaris culture is 8.69 ± 0.09. Two mutually independent models are proposed to aide in scaling up an open WW-based C. vulgaris photobioreactor. [ABSTRACT FROM AUTHOR]

Abstract In order to meet the projected demand for biomass feedstocks, multiple sources will be needed. Biomass feedstocks are often have a high degree of variability with regards to important properties such as ash, moisture, and energy content. The efficiency of conversion processes may be sensitive to this variability; thus, strategies are needed to ensure that consistent and reliable feedstocks are produced that meet end-user specifications. The objective of this study was to examine the effect of source, blending and hot water extraction (HWE) on the quality of wood pellets. Debarked maple biomass was blended at various rates with whole stem harvested willow, HWE willow, and HWE maple biomass, made into pellets and then compared to existing ISO (17225) pellet standards. Untreated willow pellets were unable to consistently meet key specifications such as ash and moisture. However, pellets blended with either HWE willow, maple or HWE maple at rates between 20 and 50 percent willow still met the most stringent requirements. HWE decreased the ash content of willow below 1% and was on par with untreated maple. HWE increased the energy content of pellets in this study approximately 1 MJ kg−1. Blending and HWE have the potential to decrease variation in feedstock for pellet production and expand the range of material that can be used while still meeting standards for quality. Technologies for rapidly assessing feedstock properties at the front or back end will be needed to maximize the benefits of these two strategies when more variable feedstocks are used. [ABSTRACT FROM AUTHOR]

Abstract Algal blooms can be harvested as renewable biomass waste for gaseous biofuel production. However, the rigid cell structure of raw algae may hinder efficient microbial conversion for production of biohydrogen and biomethane. To improve the energy conversion efficiency, biomass from an algal bloom in Dianchi Lake was subjected to a hydrothermal/steam acid pretreatment prior to sequential dark hydrogen fermentation and anaerobic digestion. Results from X-ray diffraction and Fourier transform infrared spectroscopy suggest that hydrothermal acid pretreatment leads to stronger damage of the amorphous structure (including hemicellulose and amorphous cellulose) due to the acid pretreatment, as evidenced by the higher crystallinity index. Scanning electron microscopy analysis showed that smaller fragments (∼5 mm) and wider cell gaps (∼1 μm) on algal cell surfaces occurred after pretreatment. In comparison to steam acid pretreatment, hydrothermal acid pretreatment resulted in a maximum energy conversion efficiency of 44.1% as well as production of 24.96 mL H 2 /g total volatile solids (TVS) and 299.88 mL CH 4 /g TVS. Highlights • Algal bloom from Dianchi Lake was pretreated by hydrothermal/steam acid. • The microstructural changes before and after pretreatment were comparatively revealed. • Hydrothermal acid led to the highest H 2 yield (25.0 mL/g) and CH 4 yield (299.9 mL/g). • Hydrothermal acid led to the highest energy conversion efficiency of 44.1%. [ABSTRACT FROM AUTHOR]

Biomass is one of the RES to produce power with zero CO2 emission, biomass gasification process considered as a sustainable technology for energy conversion. This paper deals with rice husk air gasification simulation using non-stoichiometric equilibrium model based on Gibbs free energy minimisation. The FACTSAGE 6.3 software used to calculate gas composition at temperature range 600-1000 °C and equivalence ratio range 0.15-0.55. Maximum gas mixture exergy of 9551.7 kJ per kg of rice husk is obtained at ? = 0.25 and 725 °C. Chemical exergy contributes 89.90-94.85% of total gas mixture exergy, cold gas efficiency and exergetic efficiency varies in the range of 25.19-70.71% and 23.11-62.24%, respectively, in operating condition. Rice husk gasification process analysed by evaluating, sustainability index and environmental destruction factor. [ABSTRACT FROM AUTHOR]