BioEnergy Research最新文献

This bibliometric and critical review examines the evolution of scientific research on biochar application in energy-crop systems, emphasizing biomass productivity, soil quality, and soil carbon sequestration from 2007 to 2025. The bibliometric assessment comprised 409 records retrieved from the Web of Science Core Collection and integrated publication trends, thematic evolution, scientific collaboration networks, and agronomic and environmental evidence. Scientific production increased markedly during the period, despite interannual variability, accompanied by a shift from biochar production and physicochemical characterization toward field-scale agronomic performance, soil–biochar interactions, pyrogenic carbon persistence, life-cycle assessment, greenhouse gas mitigation, and engineered biochars. Physicochemical characterization nevertheless remained essential for interpreting biochar functionality. Field evidence indicates that crop responses depend on feedstock origin, pyrolysis conditions, biochar properties, application rate, soil characteristics, crop species, and experimental duration. Long-term studies and assessments of pyrogenic carbon stability support the potential of biochar to increase soil carbon stocks and contribute to durable carbon sequestration, although the magnitude and permanence of these effects vary across pedoclimatic conditions and management systems. Major research gaps include limited standardization of biochar characterization, insufficient long-term field validation under tropical conditions, incomplete evaluation of the environmental safety of modified biochars, and the absence of harmonized indicators integrating biomass productivity, soil carbon dynamics, greenhouse gas emissions, and carbon permanence. Overall, current evidence supports biochar as a soil amendment and carbon-management strategy for low-carbon bioenergy systems when material properties and application practices are aligned with site-specific agronomic constraints and validated under representative field conditions.

The increasing depletion of fossil fuel resources and the growing environmental pollution associated with their utilization highlight the urgent necessity of transitioning toward clean and sustainable energy systems. Among renewable sources, biomass is considered a promising alternative due to its ability to simultaneously generate electricity and heat through Combined Heat and Power (CHP) technologies. In this context, agricultural residues, as abundant and underutilized biomass resources, offer considerable potential for bioenergy production. This study aims to assess the bioenergy potential of field and orchard crop residues in Ilam Province, Iran. The results indicate that Ilam Province possesses substantial potential for biomass energy generation, primarily due to its diverse agricultural production and large residue volumes. Based on crop yield data, wheat, barley and watermelon were identified as the major field crops, while grape, pomegranate, and olive represented the main orchard crops contributing to biomass availability and energy generation. The theoretical biomass potential from field and orchard residues was estimated at 719,190 tons, corresponding to 11,867,588 GJ of theoretical and 2,142,754 GJ of recoverable energy potential. CHP analysis demonstrated that these residues could annually produce approximately 232,963 MWh of electricity and 272,975 MWh of heat. The estimated gross Greenhouse Gas (GHG) emissions associated with bioenergy production were about 121,214 tons of CO₂ and 121,361 tons CO₂-eq per year. When compared against fossil fuel baselines, net CO₂ reduction ranges from approximately 62,163 to 96,255 tons annually for field crop residues. The findings reveal that Ilam Province, owing to its favorable climatic conditions, extensive cultivation area, and substantial agricultural residue production, holds a strong potential for the development of biomass-to-energy technologies and can play a vital role in advancing regional sustainable energy strategies.

Mono-digestion of sewage sludge (SS) is limited due to low C/N ratios, a low organic matter content and poor biodegradability of the organic fraction. Several studies recommend its co-digestion with crude glycerol (CG), a by-product of biodiesel production, to overcome these limitations. As previous studies primarily focused on process performance, this study aimed to conduct in-depth investigations into the co-digestion of SS with glycerol, combining microbial, biochemical, and process-related aspects, with a focus on the potential priming effect induced by glycerol. To avoid cross-effects, the co-digestion of SS with pure glycerol (PG) instead of CG was investigated at concentrations from 0% to 35% based on chemical oxygen demand (COD). Co-digestion with 35% PG increased methane yield by up to 148% compared to the control. Additionally, the reaction kinetics improved, with production rates reaching 85 mL h⁻¹ at 20% PG compared to 49 mL h⁻¹ in the control, enabling more targeted and demand-oriented biogas production. The lag phase was also reduced by 80%. However, no priming effects were observed. At higher PG concentrations (≥ 10%), COD degradation of PG was incomplete, while at lower concentrations (≤ 5%), COD was fully degraded. Further, co-digestion with PG did not change the dewatering properties of the digestate. PG altered microbial diversity and evenness without affecting richness, though no clear patterns emerged. Metaproteomic analysis showed that higher PG concentrations boosted methanogenesis, increasing it by 87% at 35% PG compared to the control. Overall, PG co-digestion is effective for boosting methane production, and low to moderate PG loadings (< 5%) are most efficient.

In this study, three kinds of high-performance biochar modified carbon felt electrodes were prepared by using peanut shell biochar (PSB), corn straw biochar (CSB) and pig manure biochar (PMB) as raw materials by solution impregnation-high temperature pyrolysis composite process, which were peanut shell biochar modified carbon felt electrode (PS-CF), corn straw biochar modified carbon felt electrode (CS-CF) and pig manure biochar modified carbon felt electrode (PM-CF). The experimental materials were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. It was confirmed that the biochar was successfully loaded and a three-dimensional porous structure was obtained. It was rich in oxygen-containing functional groups such as –OH and –COO–, and the thermal stability of the material was good, which laid a material foundation for improving the performance of microbial fuel cells (MFCs). In the MFC performance test, all modified electrodes showed better performance than unmodified carbon felt (CF). The MFC of CS-CF is particularly prominent: the start-up time is 44.9 h shorter than that of CF, the maximum output voltage reaches 153.2 mV, and the maximum power density is 11.9 mW/m³, which is 2.01 times that of CF group. At the same time, the removal rate of aviation fuel is positively correlated with the output voltage, and the removal rate of aviation fuel in the CS-CF group is the highest, reaching 26.23%. This study confirms that biochar modification can synergistically improve the electricity generation performance and pollutant degradation efficiency of MFC by optimizing the microstructure and surface chemical properties of the electrode, which provides a potential electrode material and technical path for environmental remediation applications such as aviation oil contaminated soil.

This study reports the one-step biodiesel production from low-cost, non-edible gurgure (Monotheca buxifolia) seed oil using a novel Na₂O/CoMn₂O₄ heterogeneous base catalyst. The thermal stabilty, crystalinity, morphology, elemental composition, textural properties and basicity of the design catalyst were comprehensively studied using thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) surface area analysis and acid-base titration. The characterization results revealed that the CoMn₂O₄ support possesed a uniform hierarchical texture, which subsequently transformed into a spongy morphology after Na₂O incorporation. The catalytic activity evaluation results signified that the synthesized Na2O/CoMn2O4 catalyst possessed good transesterification activity in the selected oil. Among them, the catalyst with 30wt% Na2O contents possessed high catalytic activity, providing a maximum yield of 95% biodiesel at 70 °C reaction temperature, 1:14 oil-to-methanol molar ratio, 8wt% catalyst loading in 350 rpm stirring speed, and reaction time of 2 h. The results are aligned with the response surface methodology (RSM) based on central composite design (CCD) producing p-value of 0.000 (high level of significance). The kinetic studies indicated that the reaction follows pseudo-first-order kinetics, acquiring an activation energy of 31 kJ mol⁻¹. The catalyst also demonstrated excellent chemical stability and reusability over seven consecutive cycles. Additionally, the produced biodiesel was in accordance to ASTM and EN quality standards, underscoring its potential as a sustainable and viable alternative fuel.

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A comparative analysis of hydrogen-rich syngas production based on biogas reforming and biomass gasification process configurations using an Aspen Plus simulation was conducted. Results showed that biogas steam reforming achieved higher H₂ content than biomass gasification but lower CO and CO₂. The syngas lower heating value (LHV) and yield (SY) achieved from the biogas steam reforming process were higher than that from biomass gasification within the range of operating conditions considered in this study. Although biogas steam reforming achieved higher LHV and SY, its cold gas efficiency (CGE) and overall energy efficiency (OEE) were about 26.60 and 19.80% lower than that from biomass gasification. The integration of biogas and biomass in a single reactor with steam addition increased LHV by 12.87% and 17.61% compared to biogas alone steam reforming and biomass steam gasification, respectively. When the process was integrated into one unit without steam addition (biogas being the main gasifying agent), the syngas LHV increased by about 14.32 and 18.98% compared to biogas and biomass alone, respectively. Biogas steam reforming and the integrated process without steam addition achieved lower CGE than biomass steam gasification and integrated process with steam addition. Among these various process configurations, integration of biomass and biogas in a single unit with steam addition exhibited the highest OEE whereas biogas steam reforming exhibited the lowest. Additionally, it was demonstrated by means of a response surface methodology (RSM) that temperature-pressure and temperature-biogas content had the strongest interaction effects on syngas composition and process performance metrics. The current study shows that integrating biogas reforming and biomass gasification can enhance hydrogen-rich syngas production. This offers a promising pathway for more efficient renewable energy systems.

Waste animal fat is an attractive low-cost feedstock for sustainable biodiesel production. However, its efficient conversion requires appropriate process optimization and reliable prediction of operating conditions. This study presents an integrated framework combining ultrasonic-assisted transesterification, response surface methodology (RSM), and interpretable machine learning (ML) to optimize biodiesel production and identify the relative importance of process variables. A five-factor, three-level Box-Behnken design (BBD) containing 46 experimental runs was employed to investigate the effects of ultrasonic power, frequency, methanol-to-oil molar ratio, reaction temperature, and reaction time. Three tree-based ML models, including Random Forest (RF), Gradient Boosting (GB), and Extreme Gradient Boosting (XGBoost), were developed and evaluated using the experimental dataset. Among the evaluated models, XGBoost attained the best predictive performance for the test dataset, with an R² of 0.8097 and an RMSE of 0.5467. SHAP analysis, permutation importance, and partial dependence plots consistently identified reaction time and molar ratio as the most significant parameters governing biodiesel yield. RSM optimization predicted optimum operating conditions of 134.74 W ultrasonic power, 26.17 kHz frequency, 6.23:1 molar ratio, 35.98 °C reaction temperature, and 8.17 min reaction time, resulting in a predicted biodiesel yield of 95.53%. Experimental validation showed less than 2% deviation from the predicted value. Physicochemical characterization, FTIR, and GC-MS analyses confirmed successful biodiesel production with fuel properties meeting ASTM D6751 requirements.

The growing global energy demand has augmented the evolution toward sustainable energy resources. Gasification converts biomass into producer gas for decentralized energy and reduced fossil fuel use. Despite extensive research on biomass gasification, limited studies have addressed feedstock-specific performance of mango wood in integrated gasifier–CI engine systems, particularly under controlled gasification equivalence ratio (GER/ER) with systematic optimization of emission and performance parameters at pilot scale. Therefore, this study evaluates the performance and emissions of a 50kW_th downdraft gasifier–CI engine system using mango wood producer gas, along with biomass and char characterization via EDS and SEM–EDX. lager gas was analysed at different engine loads and GER/ER, then tested in a dual-cylinder diesel engine and compared with pure diesel operation. GER/ER (0.25–0.39) significantly influenced gas composition and calorific value. The 14 BHP engine operated at a constant 1500 rpm with an AC resistive load bank. Results show a maximum diesel saving of 66% and the highest brake thermal efficiency of 24.69%, while minimum CO emissions 0.16 vol% were observed at 0.25 GER/ER. Optimal operation at 0.36 GER/ER and 8.81 kW achieved 57.21% diesel saving, 22.60% BTE, reduced emission and noise levels. The novelty lies in integrating experimental analysis with response surface methodology for optimization, demonstrating that mango wood–based gasification is a viable and sustainable option for efficient dual-fuel engine operation.

The financial potential of Napier grass (Pennisetum purpureum) as a feedstock for biogas-based electricity generation was evaluated by integrating field-derived biomass-yield and specific methane-yield datasets with a farmer-level economic analysis in a tropical coastal region of southern Thailand. Four species—Dwarf, Pak Chong 1, Bana, and Suvarnabhumi (a newly developed Thai species)—were cultivated under two fertilization treatments and three harvest intervals (60, 90, and 120 days). The system was assessed for sustaining a 1 MW biogas power plant, incorporating transportation distances of 10–30 km and key financial indicators, including Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PBP). The results showed that SV-F52-C60 required the smallest cultivation area (134 ± 34 ha) and was retained as the integrated system-level recommendation, whereas PC-F52-C90 achieved the highest farmer-level financial return. Under the high biomass-price scenario of $42.86/t and a transportation distance of 10 km, SV-F52-C60 generated a net profit of $3,748/ha/year, with an NPV of $21,526/ha, an IRR of 241.7%, and a PBP of 0.44 years. Fertilization enhanced economic performance by increasing biomass yield, thereby increasing NPV and IRR while shortening PBP. Increasing transportation distance reduced the modeled economic returns, although the selected high-yield cases remained profitable at 30 km. Beyond monocropping, scenario-based economic projections suggested that pineapple–Napier grass rotation could increase annual profit by 9.4–10.5%, while coconut–Napier grass intercropping could increase annual profit by 195.5–199.6%. These findings identify SV-F52-C60 as a financially competitive option requiring the smallest cultivation area for biogas feedstock production under the site-specific conditions evaluated.

Bioenergy and biofuels sourced from biomass are recognized as sustainable, renewable alternatives to fossil fuels, with the potential to reduce greenhouse gas emissions. This study explores how the circularity and sustainability of the biomass supply chain can be evaluated, specifically focusing on rice straw utilization in Vietnam, a topic that has not been comprehensively explored. To assess different sustainability and circularity supply chain alternatives for biomass to enhance utilisation of it for energy production in the Vietnamese agriculture context, an integrated Decision Support System based on a life cycle thinking approach and the multi-criteria decision making methods is employed. The study examines five supply chain alternatives for utilizing rice straw in bioenergy production in Vietnam, including anaerobic digestion for biogas and use in a CHP plant. Key sustainability and circularity indicators were analysed, including Global Warming Potential, Internal Rate of Return, job creation, and waste recycling rates. The results showed that the digestate pyrolysis alternative achieved the highest scores for sustainability and circularity. The captured and liquefied CO₂ alternative exhibited the lowest Global Warming Potential at 2.27 k.ton gCO₂eq/year, while the microalgae alternative had the highest GWP at 107 k.ton gCO₂eq/year. The digestate pyrolysis alternative also yielded the highest IRR at 20.46%, while the captured and liquefied CO₂ alternative had the lowest at 13.88%. In terms of job creation, the microalgae alternative generated the most jobs (31.11 man-years per year), and it also had the highest waste recycling rate at 90.49%. The findings suggest that integrating circular economy principles, such as upcycling waste by suitable treatment technologies, can significantly enhance the sustainability and circularity of biomass supply chains. The digestate pyrolysis alternative emerged as the most sustainable and circular option, while microalgae cultivation excelled in job creation and recycling. These insights are crucial for optimizing biomass supply chains and supporting Vietnam’s transition to a low-carbon economy.