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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

With an increasing share of regenerative wind and solar energy in electricity supply, the aspect of load flexibility will gain importance, i.e. there is an increasing need for buffer capacities and / or power plants must be able to react more flexibly to changes of the demand. As an alternative or in addition to the new construction of peak­load power plants (pump storage systems, gas power plants), load-flexible dust burner technologies can be used in existing incinerators to increase the load flexibility and the fuel flexibility when using especially local regenerative fuel sources. Flexibility of the burner concept means an increase in changing fuel composition and non-stationary operation, which may cause changes of the combustion behavior and, hence, of the emission behavior. Flexibility in fuel sources changes the combustion and emission behavior, too, especially with regard to low rank fuels with high ash contents containing chlorine and alkali species. To control these non-stationary processes in the burner and downstream boiler area for an efficient operation, contact-free optical measurement methods are applied in addition to the measurement systems existing in the furnace chamber and furthermore control methods based on computational intelligence. Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1334-1337

Agentenbasierte Strommarktmodelle werden vielfach eingesetzt, um die Entwicklung des Strommarkts und Energiesystems explorativ zu untersuchen. Häufig werden hierbei auf Basis von Eingangszeitreihen die Investitions- und Dispatch-Entscheidungen von konventionellen Kraftwerken, wie Gas- oder Kohlekraftwerke, und Speichertechnologien nachgebildet . Modelle wie PowerACE und AMIRIS nutzen Brennstoffpreisreihe, Last, Erneuerbaren-Energien (EE)-Erzeugung und Investitionsoptionen sowie den bestehenden Kraftwerkspark als Eingangsdaten. Die zu Grunde gelegte Last und EE-Erzeugung sind hierbei stark vom jeweiligen Wetterjahr, auf denen sie basieren, abhängig. Zum einen ist das Wind- und Strahlungsdargebot als auch der Wärme- und Kältebedarf, welche einen starken Einfluss auf den Strombedarf haben, jedes Jahr unterschiedlich, gleichzeitig führen technologische Entwicklungen dazu, dass eine reine Skalierung historischer Erzeugung zukünftige EE-Erzeugung systematisch unterschätzt. Es soll untersucht werden, ob die Verwendung von nur einem Wetterjahr dazu führt, dass, insbesondere bei Betrachtungszeiträumen von mehreren Jahrzehnten, es beim Vergleich zwischen verschiedenen Wetterjahren zu erheblichen Unterschieden in den Simulationsergebnissen , sowohl bei den Investitionen als auch bei den Marktpreisen, kommt. Ziel ist es die Unsicherheiten in Bezug auf EE-Erzeugung und Stromnachfrage im Agentenverhalten abzubilden. In Rahmen dieser Arbeit soll diese Unsicherheit in den Ergebnissen agentenbasierter Modelle, am Beispiel PowerACE, quantifiziert werden und dargelegt werden, ob die Verwendung von mehreren Wetterjahren oder die Nutzung synthetische Wetterjahren, also eine Kombination verschiedener Wetterjahre auf Erzeugungs- und Nachfrageseite, hier einen Vorteil bieten .

This contribution presents a user-friendly data reduction routine for Pitot probes based on widely available software with a fluid properties interface. The data reduction process rests on the general balance equations and the fluid database and calculation program REFPROP by NIST. In the corresponding calculation sheet, the user can easily select the fluid and manually or automatically insert the probe data and stagnation conditions of the measurement. A robust algorithm directly calculates the freestream Mach number and other flow and thermodynamic quantities. The new Pitot probe data reduction routine's accuracy is assessed through several test cases, including the subsonic and supersonic flow of dry air, Novec 649, and siloxane MM in the dilute and dense gas regime. For compressible non-ideal gas flows, it is found the classical Rayleigh-Pitot equation is systematically in error even in the dilute gas regime where relative deviations of more than 10 % were noticed. In the dense gas regime, the Rayleigh-Pitot equation fails dramatically in calculating the freestream Mach number, and errors larger than 60 % were observed.

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

Palm oil is the most demanded vegetable oil in the world. It serves as a raw material for a wide range of products as well as food and energy sources. However, the palm oil supply from Southeast Asian countries has been repeatedly under discussion in the EU Commission for its environmental impacts. To gain a deeper under-standing of the related costs and GHG emissions of the palm oil supply, a comprehensive modelling tool is used to assess the Indonesian supply path to Germany. Starting with the cultivation and harvesting of fresh fruit bunches (FFB), the crude palm oil (CPO) production in an oil mill and the cargo handling in Central Kalimantan, the CPO is transshipped through the seaports of Surabaya and Rotterdam to an assumed landing area in the south of Germany. The overall supply costs and GHG emissions add up to 599.08 €/t and 5,156.86 kg CO2-eq./t CPO. Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1681-1693

The relationship between the energy efficiency, energy density and complexity level of the system is here addressed from both thermodynamic and evolutionary perspectives. A case study from economic systems is presented to show that, contrary to widespread opinion, energy efficiency is responsible for energy growth and the complexity leap. This article further examines to what extent complexity, on a historical time scale, may evolve to counterbalance conservative effects brought about by energy efficiency. We analyze structural complexity growth by four different paradigms. An evolutionary pattern is then proposed that may encompass the broad dynamics underlying complexity growth. This evolutionary pattern rests on the hypothesis that thermodynamic evolutionary systems are featured from an ever growing influx of energy driven into the system by self-catalytic processes which must find its way through the constrains of the system. The system initially disposes of the energy by expanding, in extent and in number of components, up to saturation due to inner or outer constraints. The two counteractive forces, constraints and growing energy flux, expose the systems to new gradients. Every new gradient upon the system represents a symmetry rupture in components’ space. By exploring a new gradient the system imposes further restrictions on its components and increases its overall degree of freedom.

A promising way to store alternating electricity from renewable sources like wind and sun is to produce pure hydrogen via electrolysis and to use this hydrogen to synthesize liquid transportation fuels and chemicals. As presented in 2015, the Winddiesel project, carried out at Güssing, Austria, is a potential strategy to use surplus wind energy to produce hydrocarbon-based fuels, chemicals, and bio-waxes via water electrolysis and Fischer-Tropsch synthesis (FTS). By using Fischer-Tropsch (FT) diesel as a blending component with fossil diesel, a massive reduction of CO2 emissions within the transport sector can be achieved. The FT laboratory-scale plant at Güssing uses slurry reactor technology to produce hydrocarbons from biomass-derived syngas. A commercial biomass gasification plant using the dual fluidized bed technology produces the biomass-based syngas. To simulate the fluctuating hydrogen production from renewable energy sources, the load of the FT plant is varied from 70 to 150% of the standard base-load conditions. To gain comprehensive data concerning the plant performance under load-change conditions, experiments lasting 500 hours are performed with two different catalyst charges. First, a 500-hour experiment with base-load settings is carried out to obtain reference data. In the second experiment, load changes are performed using an equivalent catalyst charge. It was observed that, depending on the catalyst, almost equal results for product distribution and composition could be reached for base-load and load-change settings. Furthermore, catalytic attrition to fine particles (< 5 µm) was investigated. The amount of catalyst fines ranges from well below 20 up to 60 mg/kg of dry product wax. This means that 0.5 to 2wt.% of catalyst undergoes attrition to fines in one year. Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 960-966

In globalized commodity markets, the orientation of the economy towards bio-economy and the energy transition to renewables, biomass is gaining importance as raw material and energy source. The regional gap between demand and supply is currently overcome by global biomass trade flows as shown for agricultural products and for wood fuels. Due to the increasing demand of biomass for energy and biofuels, these trade flows will expand in the future. A comprehensive model was developed to evaluate these supply chains for biomass on industrial scale and gain a detailed understanding of its related costs and GHG emissions (± ILUC). It consists of sub-models, such agricultural or forestry production, preconditioning and processing, road, rail and water transportation, transshipment and storage. The model was applied to six exemplary biomass production and supply paths with the target destination in Central Europe (Germany) – namely ethanol from Brazil, wheat and wood pellets from Canada, soybeans from the USA, palm oil from Indonesia and round wood from Russia. This represents the broad variety of biomass sources, supply regions and transportation distances of 6,200 to 17,900 kilometers. Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 291-308