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The project between tthe Deutsche Biomasseforschungszentrum (DBFZ) and the Karlsruhe Institute of Technology (KIT) focuses on the pr rovision of alternative fuels by thermochemical conversion. Biogenic residues and wastes which are not used yet or which could be utilised more efficiently are studied. The selection of possible feedstock was supported by a techhnical potential analysis including the competition to th he food industry. The technical suitability of raw materials for the fast pyrolysis (FP) process was of special in nterest. As a possible feedstock following types of biomass were studied: corn stover, corn cobs, biogenic floating re efuse (river Rhine and Baltic Sea), scrap wood, bark, rape s straw, sunflower straw, draff, diverse residues of flour production and hay. A process development unit (PDU) with a biomass feeding rate of 10 kg/h and a twin screw m mixer reactor was used for all experiments. It was found that different types of biomass form different char, condensate e and gas yields due to varying ash levels and lignocellulosic composition. Elemental formulas for feedstock, char, organic condensate and gas were estimated independent on t the feedstock due to similar elemental compositions. Pyrolysis gas analysis during the experiments gave information on the mass yields. A CO/CO2-ratio of 1 (i.e. wood) corresponds to organic condensate yields of about 50 wt.-%%, whereas a ratio of 0.3-0.7 (straw) corresponds to 18-32 wt. .-% respectively. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 973-977

Bio-oil composition can differ depending on the biomass feedstock. Such information is essential if upgrading to a liquid fuel or to platform chemicals is intended. Furthermore, water and inorganic elements have to be taken into account for the catalyst selection. In this work, two bio-oils from wheat straw and beech wood were characterized by different techniques. Both were composed by a light and a heavy phase separately analyzed. The water content of the fractions differed over a wide range between 14.4 and 56.7 wt.% and therefore also the HHV (between 28.5 and 9.2 MJ/Kg). Both phases showed very low content of sulfur (<0.4 wt.%), which can have influence the lifetime of the catalyst. The 1H-NMR integration showed higher values in the regions of alkanes, carboxylic acid or keto-groups, and hetero-(aromatics) for both heavy phases, while light phases showed higher values in the water, O-H exchanging and carbohydrates region. So the heavy phases seem to be a good basis if phenols and its derivatives are expected and the light phases if alcohols are of interest. These results show that the bio-oils composition is essential for upgrading reactions, impacting on the products as well as on the choice of the catalyst. Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 1143-1147

Clima 2000: 01 November 1993, London, England, UK Available on CD-ROM

Chile is known for a strong forest industry based on 2.5 million ha of forest plantations. The harvest and processing of 44 million m3 of roundwood leads to a biomass potential of more than 5 million tons of plantation and sawmill residues per year which could be utilized to produce wood pellets. However, Chilean pellet mills face a limited domestic demand of approximately 100,000 tons per year. As 60% of the Chilean pulp and wood chips are shipped to diverse destinations in Asia and Europe, the export of wood pellets could offer an opportunity to utilize the potential of residual biomass. In this study, an economic assessment of the production and export of Chilean pellets is carried out. A simulation model is developed which covers the entire supply chain including pellet production, transportation and storage, port operations and maritime shipping. The model is applied to compare regular and torrefied pellets and different destination ports in Europe and Asia. The results indicate that torrefied pellets would be competitive with regular wood pellets in the considered target markets. Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 1279-1288

The purpose of Karlsruhe’s bioliq®-project is the conversion of biomass into synthetic chemicals and fuels (also referred to as BtL, biomass to liquids). The lignocellulosic biomass is first liquefied by fast pyrolysis in distributed regional plants to produce an energy-dense intermediate composed of pyrolysis condensates and solid char powder. Both products are mixed to a suspension (the so called bio-slurry or Syncrude) to be suitable for long storage periods and economic transport over long distances. Afterwards, in a large scale industrial facility, the biosyncrude is converted into syngas through entrained flow gasifier and then by catalysis to synfuels or platform chemicals. Regarding to a minimum of energy consumption for avoiding solid sediments in the biosyncrude, two possibilities are being taken into account: either the bio-slurry is continuously slowly stirred, or sedimentation is prevented by short-time stirring followed by an as-long-as-possible resting interval. For the investigated bio-slurries, the experimental results indicates, that it’s more efficient to stir the slurry batch-wise. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1151-1154

The cross sections for deeply virtual Compton scattering in the reaction $ep\to egamma p$ has been mea

There is a growing awareness of the valuable nutrients (nitrogen and phosphorus) being lost in conventional wastewater treatment systems. Although the removal of these nutrients has been well addressed, efforts for nutrient recovery have seen little development. As the emphasis on sustainability in the wastewater treatment industry increases, conventional wastewater treatment processes are being re-evaluated and new treatment systems developed. A possible nutrient recovery mechanism is the precipitation of magnesium ammonium phosphate hexahydrate (MgNH4PO4·6H2O), commonly known as struvite. Human urine has been identified as a rich source of nutrients in wastewater; hence the separate collection of urine is considered a viable method of enabling struvite recovery. Since dilution of urine to a certain degree is inevitable, reconcentration of urine beyond the solubility limit of struvite is critical. Currently available methods for reconcentration (e.g., evaporation, freeze-thaw, reverse osmosis and electrodialysis) are relatively expensive with high energy demand. Thus, the research here aims to demonstrate nutrient reconcentration from diluted urine and simultaneous organic removal by using the principles of microbial desalination cells (MDCs), where energy released from organic oxidation is partially used for the separation of nutrient ions. With reduced energy demand, a sustainable method for the utilization of source-separated urine is examined. The performance of bioelectrochemical systems relies on the activity of exoelectrogenic bacteria to transfer electrons to the anode. An examination of exoelectrogen sensitivity at various wastewater treatment conditions (i.e. ammonia and oxygen) is an important component of this research. Methanogenesis is considered the greatest challenge in achieving practical applications in anaerobic bioelectrochemical systems. An electrolytic oxygen production method is suggested for effective control of methanogenesis in a feasible and cost-effective manner. Master of Applied Science (MASc) Thesis

Latent thermal energy storages (LTESs) in combination with heat pumps and smart control strategies can maximize the utilization of renewable energy sources for heating and cooling. However, smart energy management with model predictive control (MPC) requires monitoring the total energy stored in the LTES, which is determined by the liquid fraction of the phase change material (PCM). Measuring the liquid fraction is challenging and the diverse liquid-fraction sensing approaches pose a trade-off between accuracy and ease of implementation. The present study aims to quantify the effect of the liquid fraction sensing accuracy on the performance of MPC strategies for heating systems with LTES. For this purpose, a residential heating application with an energy management system is analyzed. The heating system consists of a heat pump, an LTES and a photovoltaic array. The heat pump can be driven by the photovoltaic array and the electric grid. The energy management system uses MPC based on Mixed-Integer Linear Programming. Representative seasonal profiles for the heating load and weather conditions are used as forecasts for the MPC. The performance of the energy management system is assessed in terms of total heating cost for different error values in the estimation of the liquid fraction of the PCM in the LTES. The heating cost is found to proportionally increase with the absolute error in liquid fraction due to reduced utilization of the LTES capacity.

The fraction of the total available energy carried by photons and the fraction carried by neutral particles of all types ine+e− multihadron final states have been measured at three centre-of-mass energies between 12 and 35 GeV. These fractions are approximately 27% and 37% with no strong dependence on centre-of-mass energy and the event topology. The neutrino energy fraction is estimated to be less than 10% at the 95% confidence level.

A novel design of hybrid thermal energy storage (HTES) using Phase Change Material (PCM) was evaluated using a mathematical model. Both single and multi-tank (cascaded) storage were explored to span small to large-scale applications (200-1600 litres). The storage element was based on the concept of a fully-mixed modular tank which is charged and discharged indirectly using two immersed coil heat exchangers situated at the bottom and top of the tank. A three-node model was developed to simulate different thermal behaviors during the operation of the storage element. Experiments were conducted on full-scale 200-l single-tank sensible heat storage (SHS) and hybrid thermal energy storage (HTES) to provide validation for the mathematical model. The HTES incorporated rectangular PCM modules submerged in the water tank. Satisfactory agreement was found between the numerical results and the experimental results obtained by Mather (2000) on single and multi-tank SHS. In addition, good agreement was noticed with the experiments performed by the author on single-tank SHS and HTES at McMaster University. The developed model was found to provide high levels of accuracy in simulating different operation conditions of the proposed design of storage element as well as computational efficiency. A parametric study was undertaken to investigate the potential benefits of the HTES over the SHS, operating under idealistic conditions. The HTES can perform at least two times better than the SHS with the same volume. The PCM volume fraction, melting temperature and properties were found to have critical impact on the storage gains of the HTES. All the parameters must be adjusted such that: (1) the thermal resistance of the storage element is minimized, and (2) most of the energy exchange with the storage element takes place in the latent heat form. The performance of the single-tank HTES was evaluated numerically while operating in a solar thermal domestic hot water (DHW) system for a single-family residence. The PCM parameters were selected to maximize the solar fraction during the operation on a typical spring day in Toronto. The use of the HTES can reduce the tank volume by 50% compared to the matched size of the SHS tank. However, the HTES was found to underperform the SHS when the system was operated in different days with different solar irradiation intensities. The effect of different draw patterns was also investigated. The results indicated that thermal storage is needed only when the energy demand is out-of-phase with the energy supply. For the same daily hot water demand, different consumption profiles; ex. dominant morning, dominant evening, dominant night and dispersed consumptions, showed slight impact on the performance of the system. The concept of multi-tank (cascaded) HTES storage was explored for medium/large scale solar heating applications such as for restaurants, motels, and multi-family residences. The design was based on the series connection of modular tanks through the bottom and top heat exchangers. Each individual tank had a PCM with different melting temperature. The results showed that the cascaded storage system outperformed the single-tank system with the same total volume as a result of the high levels of sequential or tank-to-tank stratification. The use of the cascaded HTES resulted in slight improvement in the solar fraction of the system. Doctor of Philosophy (PhD) Thesis