BioEnergy Research最新文献

This study evaluates the environmental performance of anaerobic digestion (AD) of cattle manure, poultry litter, and straw in Ireland, where livestock agriculture is the second-largest source of greenhouse gas (GHG) emissions. The aim is to determine whether AD can reduce environmental burdens relative to current practices in which these residues are directly applied as organic fertilisers. A consequential life cycle assessment (LCA) was conducted in accordance with ISO standards, modelling six scenarios encompassing mono-digestion and co-digestion pathways. These were compared against fertiliser-only systems and the electricity mix across 18 ReCiPe midpoint impact categories. AD substantially reduced climate, acidification, eutrophication, and most toxicity impacts relative to direct land application. Poultry litter delivered the best performance due to its high energy content, while co-digestion with straw significantly improved cattle manure systems. Construction-related emissions were the main limitation across AD scenarios. The findings demonstrate that AD provides a more sustainable management option for Irish agricultural residues and contributes to national climate and circular-economy goals.

This study presents the design, modelling, simulation, and experimental validation of a compact pyro-gasifier system developed for the trigeneration of syngas, bio-oil, and biochar using granulated coconut shell biomass as the feedstock. The integrated approach combines MATLAB-based 3D temperature modelling, Aspen Plus process simulation, and hardware prototype testing to bridge the gap between computational analysis and practical performance. The MATLAB simulation of thermal distribution within the dual-chamber reactor revealed effective heat transfer from the gasification to the pyrolysis zone, ensuring uniform decomposition and controlled volatile release. The radial and axial heat conduction profiles, reaching up to 800 °C, confirmed stable thermal gradients essential for efficient biomass conversion. Aspen Plus simulations predicted significant energy yields with an enthalpy efficiency of 38.67%, hydrogen enrichment from 9.5% to 49.6%, and a heat recovery potential of 14.47 kW from non-condensable gases. The prototype unit, fabricated using recycled metallic components, demonstrated steady operational stability and produced distinct outputs—high-quality bio-oil characterized by dominant O–H and C = O peaks (FTIR) and porous biochar structures confirmed by SEM–EDS analyses. The results affirm that the developed pyro-gasifier ensures efficient thermochemical conversion with reduced CO₂ emissions, minimal tar formation, and high carbon recovery through dual biochar generation. The study establishes a validated, scalable framework for decentralized bioenergy generation, integrating numerical, process, and experimental domains. The proposed system demonstrates technical feasibility, economic viability, and sustainability for advancing circular bioeconomy practices using abundant coconut shell biomass.

Sugarcane vinasse is the main wastewater from the ethanol industry in Brazil, generated by the distillation of the alcoholic solution from fermentation in 10 L for each liter of ethanol produced. A biorefinery is understood as a bioprocess capable of integrating equipment and technologies with low environmental impact aimed at converting biomass to generate energy, fuels and even renewable bioproducts. One of the aspects of biorefinery is the so-called “microalgal biorefinery”, through the use of effluents in the cultivation of these microorganisms to obtain biomass rich in intracellular products. Microalgae are photosynthetic organisms eukaryotic, such as chlorophyte algae (Chlorophyta), or prokaryotic organisms, such as cyanobacteria (Cyanophyceae). Several strategies have been developed to produce microalgal biomass to use its proteins, lipids, and carbohydrates. In this context, the present study aims to evaluate the growth of the cyanobacterium Phormidium autumnale in a fed-batch with wastewater (vinasse) from sugarcane processing. The results indicated a biomass accumulation within 48 h of cultivation, with a maximum concentration of 1,450 mg L⁻¹ and conversion of 0.88 mg cells per mg carbon consumed within that period. The biomass obtained had about 43.0% proteins, 12.6% lipids and 11.4% carbohydrates, mainly arabinose, glucose, mannose, and galactose. Even though some of the estimated properties do not conform to international standards, the fatty acid profile of the microalgal biomass indicates the viability of using this oil in biodiesel production, especially considering the low costs of using vinasse.

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This study investigates the catalytic co-pyrolysis of two tropical hardwoods Ayous (Triplochiton scleroxylon) and Sapelli (Entandrophragma cylindricum) to produce a high-quality bio-oil under a bifunctional H-ZSM-5/Ni-Mo/MgO catalyst. Experimental results show that catalyst incorporation enhances bio-oil yields up to 57.3 wt% with a substantially improved energy density (28 MJ/kg), a reduced oxygen content (18 wt%), an increase of fixed-carbon content (70–75 wt%) and a higher proportion of aromatic hydrocarbons (38%). Thermogravimetric (TGA/DTG) analyses reveal accelerated devolatilization kinetics, with apparent activation energies lowered to 29–35 kJ/mol under catalysis. GC–MS and FTIR analysis confirm effective deoxygenation and stabilization of the bio-oil. Life-cycle assessment indicates a 32% decrease in greenhouse gas emissions per megajoule produced compared to diesel, while co-produced biochar provides long-term carbon sequestration benefits. Together, these findings highlight the catalytic co-pyrolysis of tropical hardwoods as a robust, sustainable strategy for valorizing underutilized forest residues into renewable liquid biofuels with higher fuel properties and a reduced environmental footprint.

Efficient production of renewable bioenergy from loblolly pine (Pinus taeda L.) forest residues (juvenile wood, branches, needles, and bark) depends on detailed knowledge of chemical variability of tissue components. We examined the composition of loblolly pine forest residues collected from plantations at first thin and final harvest from three physiographic regions (Piedmont, Upper and Lower Coastal Plain) in the southeastern United States. The pure fractions were chipped, oven-dried, and then sieved with 3 mm and 7 mm size classes retained for analysis. For each stand and size class, mixed fractions containing a representative sample from the pure fractions were prepared. Extractives, ash individual sugars (glucan, xylan, galactan, arabinan and mannan), and lignin (total, acid soluble, acid insoluble) contents were measured for each pure and mixed sample. Analysis of variance using mixed-effects models was used to determine differences in chemical composition based on tissue fraction and size class, with significant differences tested using Tukey HSD. Extractives, sugars, and lignin contents were significantly different between tissue fractions and size class. Mean total lignin content was highest for bark (47.3%) and lowest for juvenile wood (30.1%). Glucan in branch (35.5%) and mixed fractions (38.8%) was significantly higher in the 7 mm size class. For pure fractions, wood had the least variability by stand and size class whereas the mixed fraction had the highest variability in individual sugar contents, and bark for lignin content. Results reveal significant tissue-specific chemical variation in loblolly pine residues supporting improved efficiency and value recovery in bioenergy applications.

This study evaluates the potential of citrus fruit pulp residue for obtaining butanol or lactic acid via fermentation by Clostridium beijerinckii. The citrus fruit pulp residue contains 44.4 ± 1.2% w w^− 1 of total sugars and is recalcitrant because it has high lignin content (15.9 ± 0.9% w w^− 1). Nevertheless, microwave-assisted pretreatment of this residue at 173 °C for 2.3 min in water recovered 63% of sugars, and subsequent enzymatic hydrolysis with Cellic CTec2 at 10 FPU g^− 1 increased sugar recovery to 73%. Further detoxification of the hydrolysate with activated carbon at 2% (w/w) removed 83% of the fermentation inhibitors and caused only 4% of sugars to be lost. Fermentation assays demonstrated that the detoxification step was crucial to direct the fermentative product. Fermentation of the non-detoxified hydrolysate yielded up to 22.9 g L^− 1 of lactic acid (yield 0.79 g g^− 1), whereas fermentation of the detoxified hydrolysate yielded up to 5.3 g l^− 1 of butanol (yield 0.2 g g^− 1). Therefore, deciding whether to ferment the non-detoxified or the detoxified hydrolysate of citrus fruit pulp residue allows the final product to be selected on the basis of market demand and resource availability. This innovative approach reduces environmental impact by offering a flexible and sustainable alternative for reusing citrus fruit pulp.

The efficiency of anaerobic digestion (AD) is often constrained by limited microbial attachment surfaces and suboptimal environmental conditions. This study investigates the effectiveness of sodium hydroxide (NaOH)-activated and zinc chloride (ZnCl₂)-activated ceramic bio-rings (CBR) in enhancing biogas production. The objectives are threefold: (1) to evaluate biogas production from landfill leachate (LFL) and food waste (LFW) using Biomethane Potential (BMP) tests with non-activated, NaOH-activated and ZnCl₂-activated CBRs; (2) to compare the performance of NaOH-activated and ZnCl₂-activated CBR in a semi continuous study under varying organic loading rates (OLRs); and (3) to assess the forecasting accuracy of artificial neural networks (ANN) and support vector machines (SVM) in predicting biogas production. NaOH-activated CBR and ZnCl₂-activated CBR underwent sequential thermal treatment at 103 °C and 700 °C to enhance their surface area and pore structure, thereby improving their effectiveness as support media in anaerobic digestion. BMP test C (NaOH-activated CBR) produced a maximum of 5531 mL biogas, a 29% increase over BMP test A (without support). In the semi-continuous study, the NaOH-activated CBR achieved 34% and 32% increases in SMP and biogas yield, respectively, compared to the ZnCl₂-activated CBR. A stable ratio of intermediate-to-partial alkalinity (IA/PA) ratio of 0.25 indicated effective buffering. NaOH activation notably improved surface area (2.56 m²/g) and pore size (2159.03 nm), leading to superior biogas output. In forecasting, SVM outperformed ANN with higher accuracy (R² = 0.9306 vs. 0.8846). These findings demonstrate that an integrated approach through activated CBR, a novel activation method, and machine learning prediction can enhance anaerobic digestion efficiency for high-strength organic waste.

The escalating global energy crisis, exacerbated by an enduring reliance on fossil fuels, necessitates an urgent transition towards cleaner, sustainable energy alternatives. While numerous reviews have addressed the fundamentals of anaerobic digestion (AD), few have critically synthesized recent advancements in pretreatment and co-digestion strategies alongside. This review provides a focused evaluation of how biomass pretreatment and synergistic co-digestion approaches address the complex structure of lignocellulosic feedstocks and process instability. We highlight contradictions in recent findings such as varying efficiency of alkaline pretreatment versus fungal bio-pretreatment and discuss emerging techniques that enhance process robustness. In addition, we analyse the techno-economic feasibility and policy frameworks shaping the scalability of biogas plants, emphasizing the need for integrated approaches that combine process innovation with supportive governance. Current work provides a comprehensive overview of biogas technology, positioning it as a pivotal solution within the global energy landscape. The analysis effectively establishes the context of the global energy crisis and the imperative for renewable energy, offering a detailed exposition of the anaerobic digestion process. It thoroughly addresses both the inherent advantages of biogas and the multifaceted challenges impeding its widespread adoption. This paper identifies critical research gaps and proposes specific, actionable future directions for optimizing biogas production and accelerating its widespread adoption as a sustainable energy solution.

Paulownia forestry in Japan has traditionally focused on producing high-value solid wood for traditional household goods. In the present study, to explore the potential of a new Paulownia plantation forestry model aimed at meeting Japan’s increasing demand for biofuels, the volume and weight of stems and the fuel characteristics of wood and bark were investigated for 15 four-year-old Paulownia trees planted in Tochigi, Japan. Fuel characteristics were also examined for nine common Japanese species as a reference. For Paulownia species, the bark had higher extractives, ash, and Klason lignin, lower contents of holocellulose and α-cellulose, and higher gross calorific value than wood. Potassium was the predominant inorganic component in both wood and bark in Paulownia species. Although the gross calorific value per unit volume of Paulownia species was the lowest among the tested nine Japanese species, the estimated annual gross calorific value per unit area was almost the same between Paulownia species and Cryptomeria japonica (the most common plantation softwood species in Japan) when the whole stem was used for biofuel production. Thus, Paulownia species might be used for biofuel production under short rotation cycles, even in lower bulk density of wood. On the other hand, wood from higher stem positions exhibited lower moisture content in Paulownia species. Therefore, drying costs might be reduced by using the lower stem portions for solid wood production, improving the overall economic efficiency of biofuel production.