• European Marine Science
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Abstract By displacing oil in porous media with other fluid, different mechanisms of fluid displacing occur. The importance of understanding the trapping mechanisms like pore body filling is irrefutable. Pore body filling mechanism with a coordination number of four has different events like I0, I1, I2 and I3. Previous studies showed that the event of I0 occurs when the pore is only filled by a compressible non-wetting phase, but this study showed that this event could also occur by an incompressible non-wetting phase. Trapping mechanisms can be examined in a glass micro-model. In this research, a glass micro-model with three different patterns was used. Results showed that at two spots of the micro-model, the mechanism of the pore body filling (PBF) for the I0 event could be occurred by an incompressible non-wetting phase. The occurrence of the I0 event was performed after the events: corner film flow of wetting phase from one of the four-junction of the pore, then swelling wetting phase at the throat and at last snapping-of non-wetting phase at pore centre. By using this new mechanism, one can achieve more accurate simulation and modelling of fluid flow through porous media. This issue is necessary for pore network modelling of oil-wet fractured reservoirs.

Abstract A supply chain network MILP model, developed by means of AIMMS software, and a process plant simulation model, developed by means of Aspen Plus®, are combined for the optimization of a biorefinery network. Optimization of the supply chain network is initially addressed using literature process and economic data. The results are used as input in the Aspen Plus® model where the technical and economic performance of the biorefineries is calculated rigorously. The two computational tools are iteratively executed until convergence on number, locations and size of the biorefineries and on process yield to products and total costs is achieved. The final results are used to perform the Economic Value and Environmental Impact (EVEI) analysis of the overall biorefinery network. The methodology is applied to a case study concerning the deployment of cereal straw in Germany to produce ethanol, ethyl levulinate and electricity. Optimization results reveal that the wheat straw supply network with four biorefineries is economically feasible and determines an environmental margin in terms of equivalent emissions savings of about 4 Mt of CO2 per year.

The thermal decomposition of ethyl acetate was experimentally studied in a newly designed fast pyrolysis set-up. The results were compared to theoretical calculations and literature values in order to proof the experimental concept. The reaction was carried out in a free fall tubular reactor with a residence time of 0.15 s. The identification and quantification of products stream composition was performed online using a GC-TCD/FID. First, an overview of the reaction rate at feed volumes of 0.25, 0.50 and 0.75 mL was obtained at reaction temperature between 400 to 600 degrees C in intervals of 50 degrees C. As a result mass transfer limitation for feeds larger than 0.5 mL were identified. For the second approach, a constant feed volume of 0.25 mL and temperatures between 420 to 550 degrees C were investigated. Using the experimental results, a global kinetic model is proposed for the thermal decomposition of ethyl acetate into ethylene and acetic acid through a first order unimolecular reaction. Also, theoretical calculations were performed at wB97XD/6-311++G(d,p) level. A concerted mechanism through a six-membered transition state was identified in the reaction path. The theoretical and experimental activation energy values lie within the literature values between 193 and 213 kJ/mol. 2020 The Authors. Published by Elsevier B.V. on behalf of Institution of Chemical Engineers. This is an open access article under the CC BY-NC -ND license (http://creativecommons.orgilicenseseby-nc-nd/450/).