Despite early momentum, large‐scale production of cellulosic ethanol has yet to achieve its expected breakthrough. The sector has faced setbacks, including project cancellations, unmet capacity targets, and the closure of key plants. Drawing on 15 years of monitoring the industry, we examine the underlying causes and evaluate the status of demonstration plants recorded in the International Energy Agency (IEA) Bioenergy Task 39 database. Following an initial period of progress up to 2015, when 50 facilities were operational, many projects were either canceled or idled. The expected capacities were not reached, and the anticipated breakthroughs have not materialized. The slow advancement of cellulosic ethanol development has occurred due to technological complexity, limited feedstock availability, high production costs, and modest commercial outcomes. Investor confidence has been further undermined by inconsistent policy support, competition from lower‐cost biofuels, and the collapse of several large‐scale ventures. In recent years, however, cellulosic ethanol production has shown promising progress and capacity to expand, particularly in rapidly developing economies such as Brazil and China. Success in these regions depends on a combination of measures: a regulatory framework that provides market incentives and offsets higher production costs, sustained support for technological research and development, and public funding for large‐scale, first‐of‐a‐kind facilities. Brazil currently leads the field, largely because cellulosic ethanol production from sugarcane bagasse is integrated effectively into existing sugar and ethanol industries.
The variability of laboratory Kraft pulping experiments is often overlooked, despite its importance for accurate data interpretation (e.g., pulp yield or Kappa number). Neglecting variability can lead to incorrect conclusions, especially when differences between cooking procedures are minor. This study assessed the repeatability and variability of a fully automated state-of-the-art laboratory scale recirculation digester and a common laboratory rotary digester, cooking spruce and pine mixtures under identical conditions. The baseline configuration utilized fractionated chips pulped with white liquor and water. To explore increased complexity, subsequent experiments incorporated unfractionated chips, segregated chips, and the addition of black liquor. Seven experiments were conducted per setup, using a liquor-to-wood ratio of 7:1, a final H-factor of 1005, and an effective alkali concentration of 50 g/L. The resulting average total yield ranged from 47.19
As the iron and steel industry needs to cut its CO2 emissions drastically, much effort has been put into establishing new—less greenhouse-gas-intensive—production lines fueled by hydrogen and electricity. Blast furnaces, as a central element of hot iron production, are expected to lose importance, at least in European production strategies. Yet, blast furnaces could play a significant role in the transitional phase, as they allow for the implementation of another CO2-reducing fuel, carbonized wood reducing agents, as a substitute for coal in auxiliary injection systems, which are currently widely used. Wood carbonization yields vastly differing fuel types depending on the severity of the treatment process, mainly its peak temperature. The goal of this study is to define the lowest treatment temperature, i.e., torrefaction temperature, which results in a biogenic reducing agent readily employable in existing coal injection systems, focusing on their conveying properties. Samples of different treatment temperatures ranging from 285 to 340 °C were produced and compared to injection coal regarding their chemical and mechanical properties. The critical conveyability in a standard dense-phase pneumatic conveying system was demonstrated with a sample of pilot-scale high-temperature torrefaction.
This study explores AnMBR technology as a promising method for treating wastewater from the meat-processing industry by analysing its characteristics and impact under continuous feeding. The solids were retained, utilising an ultrafiltration membrane with a pore size of 0.2 µm, and the efficacy of reducing the organic load was evaluated. Although the COD removal rate decreased from 100% at an OLR of 0.71 g/(L*d) to 73% at an OLR of 2.2 g/(L*d), maximum methane yields were achieved at the highest OLR, 292.9 Nm3/t (COD) and 397.8 Nm3/t (VS) per loaded organics and 353.1 Nm3/t (COD) and 518.7 Nm3/t (VS) per removed organics. An analysis of the microbial community was performed at the end of the experiment to assess the effects of the process and the substrate on its composition. The AnMBR system effectively converts meat-processing wastewater into biogas, maintaining high yields and reducing the loss of dissolved methane in the permeate, thanks to a temperature of 37 °C and high salt levels. AnMBR enables rapid start-up, efficient COD removal, and high biogas yields, making it suitable for treating industrial wastewater with high organic loads, enhancing biogas production, and reducing methane loss. Challenges such as high salt and phosphate levels present opportunities for a wider use in nutrient recovery and water reclamation.
After years of development of the dual fluidized bed gasification process with woody biomass, new challenges arise with a wider range of feedstocks, such as agricultural residues or waste fractions, gaining importance. This work presents the results from the operation of a 1 MW advanced dual fluidized bed (aDFB) gasifier at the Syngas Platform Vienna, with cashew shells (CS) as feedstock and pure olivine or olivine mixed with 33% limestone as the bed material. Two operation points, different in their main process parameters, with CS as feedstock were performed for a minimum of 16 h. Due to the high calorific value (22.7 MJ/kg dry) and high content of volatile components (81.7 wt % dry), CS are well suited for gasification. During the operation, a product gas with a H2/CO ratio of 1.93-2.29 was produced, which suits the use of the syngas as input for Fischer-Tropsch synthesis. Due to the low ash softening temperature of CS of about 840 degrees C, determined in ash fusion tests and predicted by thermodynamic equilibrium calculations, the operating temperature in the gasifier was kept below 820 degrees C in the first operation point with around 20 h of runtime. Bed material samples after the operation revealed the formation of agglomerates, which were analyzed by SEM and EDS for their morphology and composition. During the second operation point, temperatures in the gasifier were increased to 870 degrees C for 16 h, while no agglomeration tendencies were observed. Both operations did not show changes in fluidization behavior compared to operations with wood chips (WC). The evaluated key performance indicators were compared to aDFB steam gasification of WC as the reference.
