http://hdl.handle.net/11336/296 Articulos de INST.DE DESARROLLO Y DISEÑO (I) Mon, 08 Apr 2024 20:50:48 GMT 2024-04-08T20:50:48Z http://hdl.handle.net/11336/228330 Enriching the conceptual modelling approach with environmental considerations: Application to the partial dealcoholization of wines Figueroa Paredes, Danilo Alexander; Sánchez, Ramiro Julián; Morero, Betzabet del Valle; Fernández, María Belén; Espinosa, Hector Jose Maria In this work, and based on results from conceptual models, an environmental impact assessment was carried out using the ReCiPe midpoint and endpoint methodology for technologies in the partial dealcoholization of wines; namely, evaporative pertraction (EP), nanofiltration (NF), reverse osmosis (RO), pervaporation (PV), pervaporation with heat integration (PVHI) and spinning cone column (SCC). While the first three technologies are analyzed in their hybrid process version including a distillation stage, the PVHI variant considers the energy integration between the retentate and permeate streams through a vapor compression refrigeration system. In all cases, a decrease of ca. two percent points of alcohol in volume is considered. With the same input data the utility costs of each variant were also estimated. In this way, trade-offs between the economic and environmental performance of each alternative were addressed. In all cases, both a partially dealcoholized wine and an ethanol-rich effluent (50 % by volume or more) were obtained with the last sent to a distillery for material valorization. Regardless of the end point chosen, the PVHI variant showed the best environmental performance and thus was the most environmentally friendly alternative followed by variants SCC, PV, RO, NF and EP. On the other hand, from perspective based on utility costs results showed that the SCC variant requires the lowest costs, followed by the PVHI, PV, EP, RO and NF alternatives, respectively. From both economic and environmental point of view EP, NF and RO and were the worst alternatives given by the relatively high steam and cooling water consumptions required for these technologies to both achieve an alcohol-rich distillate with and a reduction in deionized water consumption of the corresponding partial dealcoholization step. In contrast, due to the high ethanol selectivity of the PDMS membrane used in experiments and the high ethanol recovery in conjunction with a high distillate composition achieved in the spinning cone column made alternatives PVHI and SCC as the better ones both in environmental and economic standpoints. It is precisely the possibility of heat integration of the pervaporation that accounts for the better environmental performance of the PVHI variant. Wed, 01 Mar 2023 00:00:00 GMT http://hdl.handle.net/11336/228330 2023-03-01T00:00:00Z http://hdl.handle.net/11336/227164 Biogas Quality Was Increased by Pulsed Feeding of Acclimated Pig Slurry with Corn Screenings and Microbiological Analysis at Each Stage Galvan, Maria Jose; Degano, Salvador; Cagnolo, Mara Beatriz; Badín, Francisco Tomás; Becker, Analía; Hilbert, Jorge Antonio; Fuentes Mora, Mauren; Acevedo, Diego Fernando Pig production in Argentina increased by > 230 % between 2008 and 2019. Pig farms are concentrated in the country’s agricultural areas, where grain availability, slaughter, and consumption centers are also located. Based on this, a proposal involving the use of agricultural by-products to produce biogas would be economically viable. To this end, we report an increase in biogas quality by pulsed feeding of acclimated pig slurry with corn screenings. The degassing process and the pulsed feeding acclimatization of pig manure obtained from stabilization ponds using corn screenings residue at a lab scale were studied. Also, the microorganism’s variability and abundance at each stage were evaluated. The results indicate that degassed pig manure results from a good alternative to use as inoculum. The methane production increased by 30 %, mainly in the lag phase, by acclimatization of pig slurry with corn screenings and the composition of the biogas is more stable in successive feeding. Although it shows that degassed pig manure can be used as inoculum, an ACoD with a high carbon source to increase daily methane yield is needed. Microbiological analyses showed an increase in hydrolytic and fermentative populations at each acclimatization stage, indicating a positive influence on the bacterial microbiome. In addition, it has been demonstrated that pulsed feeding of acclimated pig slurry with corn screenings can increase biogas quality, and the procedure has a positive influence on the bacterial microbiome. Sun, 01 Oct 2023 00:00:00 GMT http://hdl.handle.net/11336/227164 2023-10-01T00:00:00Z http://hdl.handle.net/11336/225551 Resources synchronization in a full truckload pickup and delivery problem: An exact approach Melchiori, Luciana; Nasini, Graciela Leonor; Montagna, Jorge Marcelo; Corsano, Gabriela In this work, the Unpaired Full Truckload Pickup and Delivery Problem with Resource Synchronization is modeled and solved, where routes must be determined to transport commodities from pickup to delivery locations by a set of vehicles, subject to timing and resource synchronization constraints, to satisfy demands at minimum cost. Unlike previous works, the use of multiple resources for loading and unloading tasks at each location are considered and appropriately managed through a representation using discrete shifts. An integer linear programming model is proposed to simultaneously solve allocation, routing and resources synchronization optimization problems. In order to improve the model performance for large size instances, diverse reformulations, including additional inequalities and symmetric-breaking constraints, are implemented and tested. Moreover, a heuristic procedure is proposed to provide good initial feasible solutions. The capabilities of the proposed approach are assessed through several examples. Wed, 01 Mar 2023 00:00:00 GMT http://hdl.handle.net/11336/225551 2023-03-01T00:00:00Z http://hdl.handle.net/11336/224771 Multi-objective optimization of a lithium cell design operating in a cyclic process Aimo, Corina Eva; Schmidhalter, Ignacio; Aguirre, Pio Antonio Multi-objective optimization frameworks of lithium-ion whole-cell design operating in a cyclic process are presented in this paper. The objective functions involved are maximization of capacity, maximization of specific energy in discharge and maximization of cycle energy efficiency. The considered design variables are electrode thicknesses, solid volume fraction and porosity of electrode compartments, and cell mass per unit cross-sectional area. In addition, the constant current value of charge and discharge is optimized. A phenomenological mathematical model developed in GAMS (General Algebraic Modeling System) environment is applied to achieve the stated goals and the multi-objective problems are solved using an epsilon constraint method-based, which is effective for finding solutions in non-convex feasible regions. Solutions for two different cell chemistries are analyzed: LMO and LCO. Pareto curves and surfaces are obtained and sets of solutions with the highest contradictions and with the most balanced agreement between the objectives involved are identified. When comparing optimal LMO designs with optimal LCO designs, the former result on average 48 % less capacity, 19 % less specific energy and 31 % more energy efficiency. Results show that material type-dependent variables such as active solids have a strong influence on the specific energy and cycle energy efficiency. While the electrode thicknesses show a general trend regardless of the type of chemistry, presenting a strong influence on cell capacity values. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/11336/224771 2023-01-01T00:00:00Z