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Dynamic pressure measurements are introduced as a powerful tool to detected filter failures at early stage. Filter failures such as leakages and blockages can be detected during back pressure recleaning pulses. High frequency sensors enable the recording of the recleaning pressure pulse. Patchy cleaning and depth filtration can be detected much faster with dynamic pressure measurements than with differential pressure measurements. Parameters derived from dynamic pressure data can be observed over time and compared with reference data. The method complements conventional pressure difference measurements and is applied at a hot gas filter that implements coupled pressure pulse (CPP) technology. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 837-843

Enrichment of activity sludge allowed to select a suitable microbial mixed culture able to grow on crude glycerol as the only carbon source, using a very simple synthetic medium without any extra nutrient supplements. Following to statistical optimisation, the selected pool was able to effectively convert crude glycerol into H2 and ethanol, both at a near¬stoichiometric yield. Subsequently, upscale tests were performed to validate the statistical model, and fed¬batch tests, in non¬sterile conditions, led to a three¬fold increase of ethanol production, thus reaching 26g/L, while producing up to 9L of H2. These results were obtained without the use of vitamin¬ and trace element solution, tryptone or yeast extract. Based on these findings it seems feasible to totally exclude the use of any synthetic medium for glycerol fermentation, through the co ¬fermentation with other waste/residual (organic) compounds, i.e. proteins and carbohydrates derived from the microalgae. In this way it might be possible to link 3rd generation biodiesel with H2 and ethanol production, while avoiding the competition with food feedstock and agricultural land use. Moreover, the valorisation of crude glycerol (converted into high¬ value products) might contribute to enhance the economic viability of microalgae feedstock and biofuels, which are, at the moment, still too costly to be commercialized. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 713-716

Different process configurations for the energetic valorization of Ricotta Cheese Whey (RCW), a dairy byproduct, were investigated by mesophilic Anaerobic Digestion (AD) under continuous operation mode using a Mono-phase (MPR) and two Bi-phase (BPR1 and BPR2) Continuous Stirred-Tank Reactors (CSTRs). The results showed an increase in CH4 production (21,4%-17.3%) and in CH4 content in biogas (19%-4%), in BPR1 and BPR2 respectively, compared to MPR (9.59±0.54NLCH4/d; 56.3±0.65%CH4). Although in BPR1 first phase, it was found negligible H2 production (BPR1=0.07±0.002NLH2/d; 1.1±0.4%H2; BPR2=3.91±0.50 NLH2/d; 39±2%H2), a methane production comparable to BPR2 was achieved, showing that the fermentation processes that occurred in the first phase can increases the final production of CH4 regardless of the metabolic pathway. Low H2 production in BPR1 contrasts with the high acetic acid concentration detected (19.30±1.4 mM), suggesting the establishment of an alternative pathway, the homoacetogenesis, which consumes H2 and CO2 to produce acetic acid. In order to investigate the effect of phase separations in BPR1 and BPR2, the microbial community composition was analyzed in methanogenic reactors by Fluorescent In Situ Hybridization (FISH) in terms of Eubacteria vs Archaea and, inside the acetotrophic methanogenic guild, for Methanosarcina vs Methanosaeta. FISH analysis reveal the predominance in BPR1 of Methanosarcina (9,4% vs 16,5% of total acetotrophic Archaea), compared to Methanosaeta, which predominate in BPR2 (8,4% vs 16.8%). Performing an economic feasibility analysis, the energetic valorization of dairy wastewater was result sustainable and profitable, pursuing the biorefinery concept. Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 599-607

The purpose of Karlsruhe’s bioliq®­project is the conversion of biomass into synthetic chemicals and fuels by producing process energy in two steps to achieve a desirable high carbon dioxide reduction. The lignocellulosic biomass is first liquefied by fast pyrolysis in distributed regional plants to produce an energy­dense intermediate composed of a viscous biooil and a high­energy char powder. Both products are mixed to a suspension (the so called bio­slurry or bioliq­ SynCrude®) to be suitable for long storage periods and economic transport over long distances. Afterwards, the biosyncrude is converted into syngas through entrained flow gasifier and then by catalysis to synfuels or platform chemicals. The focus in this study is the mixing process of the bioslurry. Therefore, the char and the liquid phase are mixed by a laboratory scale colloidal mixer (5 litres) to determine the energy consumption during mixing. The investigations are being carried out with a model slurry (suspension of ethylene glycol and char powder) to be adequate with the start­up conditions of the Karlsruhe pilot gasifier test in January 2013. The most influencing parameters in the mixing process are the particle size distribution and the mixed volume, followed by the length of the impeller blade and an additional ring to create extra shear stress on the suspension. It is concluded, that it is more efficient to mix two batches of two litres, than one batch with three litres. Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 956-961

The common way of handling sludge from pulp and paper (P&P) mill.s wastewater treatment plant (WWTP) is combusting it at the site. Combustion is rather a way to dispose the sludge than take advantage of its energy content. This case study assesses the potential to convert the wet low-value feedstock, specifically WWTP.s secondary sludge, to a more valuable bioenergy product called HTC biocoal through hydrothermal carbonization (HTC) combined with wet oxidation using C-Green.s innovative OxyPower HTC technology. We assess the integration to a Nordic sulphate pulp mill as a retrofit and compare it to baseline scenario of combusting sludge in the recovery boiler. The approach contains assessment of effects of integration to pulp mill.s mass and energy balance, and market, economic and environmental assessments. The results show that the retrofit has positive impacts on the pulp mill.s mass and energy balance, such as reduced evaporator and recovery boiler load. Greenhouse gas emissions reduction of 77% compared to baseline scenario proved the environmental benefits of the retrofit. However, it is challenging to find an economic case for HTC biocoal production in P&P industry due to efficient sludge treatment already taking place. Furthermore, End-of-Waste status is needed before entering the markets. Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 954-960

Upgrading of bio-oils for using them as transport fuel or as source for chemicals is a challenging task that has recently attracted a lot of attention. One of the most studied approaches in literature is hydrodeoxygenation, which is also the topic of this work. The light phase of a pyrolysis oil, produced in the bioliq® pilot plant in Karlsruhe, was treated with hydrogen (80 bar, pressure at room temperature) under mild hydrotreating conditions (250°C) in the presence of a catalyst. Different nickel-based catalysts were employed and were compared to Ru/C as benchmark. Nickel on different high surface area supports showed similar catalytic performance with inferior hydrogenation performance compared to Ru/C. Extensive quantitative 1H-NMR analysis was used for observing variations in the concentration of specific molecular functional groups in the products, while the distribution of the main elements (C, H, O) in the different phases was determined by elemental analysis and Karl Fischer titration. 1H-NMR and elemental analysis showed that the produced oil has less oxygen content respect to the original bio-oil. This is not only due to the hydrotreating reaction but also to the repartition of apolar compounds in the oil phase and of more polar ones in the aqueous phase. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1164-1170

The feasibility of hydrothermal liquefaction of lignocelullosic biomass available in large amounts in Brazil, sugarcane straw and sugarcane bagasse, was evaluated in this study. The conversion of this lignocellulosic residues took place at 300 ºC and 350 ºC at residence times from 20 up to 240 minutes. Overall, the reactions produced more than 92% of liquid products and minor formation of solid and gaseous products. The highest yield of monomers was obtained at 350 ºC and reaction time up to 90 min resulting mainly in cathecol, phenol and guaiacol. Therefore, both sugarcane bagasse and straw show potential to be used as a feedstock to produce platform chemicals via hydrothermal liquefaction, which could be integrated in the already well stablished Brazilian sugarcane biorefineries. Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 951-953

Production of microalgae biomass as an alternative feedstock for biodiesel is a promising technology. The reduction in energy consumption of traditional algae cultivation systems is today one of the most important issues towards sustainable biofuel production. In the MAMBO project an innovative pond has been designed and realized to investigate the possibility of reducing energy consumption of the cultivation phase as well as the use of water. The aim of this project is in fact to demonstrate the possibility of using algae as an alternative and cost­effective feedstock for the biodiesel industry. The innovation is based on the reduction of the mean fluid velocity in the pond and the reduction of the water head, while maintaining sufficient turbulence and recirculation of the culture. The typical energy demand for mixing in a traditional raceway pond, operated at 20 cm depth and 20 cm/s speed, is estimated in 0.034 W/m2. The reduction in fluid velocity has a large impact on the energy demand of the cultivation phase (essential in view of biofuel production), nevertheless the major drawback is that it also reduces the effectiveness of mixing, which is a key factor to obtain high productivity per unit area. A reduced culture depth also offers the advantage of a lower amount of water needed per square meter of pond maintaining the same area for solar energy input and leads to higher algae concentration in the fluid medium. Injection and solubilisation of carbon dioxide in the fluid stream also deserve attention. Systems have been developed in the innovative pond to avoid or reduce uneconomical CO2 losses. The real flow field in both the traditional and the innovative ponds was evaluated by velocimetry measurement under actual operation conditions. The methodology adopted in this research work was based on a combination of numerical and experimental activities. A numerical tool was designed to estimate the effect of the reduction in fluid velocity and culture depth on energy consumption and mixing. The results obtained from numerical simulations were then used in designing the innovative pond and defining the main operational parameters and characteristics. Tests on the traditional raceway pond and on the innovative one were carried out during summer 2010 in Florence (Italy). The on­field collected data were elaborated linking microalgae productivity to solar input and energy consumption. The preliminary results obtained during the first year of experimentation showed that the innovative pond has a slightly lower productivity compared to the traditional pond, but needs significantly less energy and water. The solutions tested in this research is already interesting in all the country where water is a precious resource and land is often not yet profitably used. Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 90-93

To investigate the influence of varying seeding time on sorghum growth, yield, water use efficiency (WUE) and potential energy output, a three¬year field experiment was carried in Northern Italy, comparing early (E; early April) and late seeding (L; mid May) in three sorghum genotypes (sweet, fibre and forage hybrid). L achieved about the same plant height as E, one month later. Differences among genotypes were more consistent (fibre = sweet > forage hybrid). Dry biomass yield outlined a similar picture: no substantial difference between E and L even in the year (2011) at strong summer drought, a circumstance which was expected to affect more L than E. WUE slightly decreased when passing from E to L in the two years (2009 and 2011) featuring high trait levels, possibly due to resuming rainfalls at the end of summer, too late for efficient water use. Given a similar fibre composition, potential energy output (electricity, bio¬methane and 2nd generation bio¬ethanol), assessed through coefficients and formulas, reflected dry biomass yield. The resilience to varying seeding time could be used to better exploit the potential for biomass production throughout the year, alternating or double cropping sorghum with other irrigated or rain¬fed crops. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 252-257