V Congreso de Innovación Docente en Ingeniería Química

Innovación EducativaElaboración de screencasts/podcasts (vídeos que resultan de la grabación de imagen de pantalla y el sonido de las explicaciones del docente), que substituirán a una parte substancial de las explicaciones teóricas que tradicionalmente se llevan a cabo en el aula. Este método persigue resolver el problema de falta de tiempo, detectado en múltiples asignaturas, para aplicar el desarrollo práctico de los conocimientos adquiridos.Proyectos de Innovación Docente de la Universidad de Valladolid 2019/2

Energy integration of high pressure processes using gas turbines and internal combustion engines

High pressure processes (e.g. sustainable hydrothermal manufacturing of nanomaterials [1], supercritical water oxidation (SCWO) [2] and biomass hydrolysis [3]) require high operational conditions. Water at high pressure and temperature conditions improves kinetic, selectivity and efficiency of these processes but entail high-energy operational expenditure. Use of fluids at high operational conditions makes necessary to supply heat of high quality, as well as power. Because of this, it is necessary to study reasonable solutions for energy recovery and integration in order to achieve the energy self-sufficiency of the process and, if possible, the net power production and with a viable efficiency [4]. In this work, the energy integration of supercritical water oxidation process is being studied. One solution that has been recently proposed is the integration of supercritical processes with energy production in cogeneration or Combined Heat and Power (CHP) cycles. Cogeneration is defined as the simultaneous production of various forms of energy – being the most frequent heat and shaft work, i.e., power – from one power source. The implementation of CHP processes is often joined to the use of gas turbines (GT) [3, 5]. SCWO process produces a high pressure reactor outlet stream, being these mainly composed of water, nitrogen and carbon dioxide and can be thermally integrated if there is a necessity of heat in other parts of the process. At the same time, it is possible to use this effluent to implement a steam injection in the gas turbine, which will improve the efficiency of the global process. This mechanism links the process of SCWO with the cogeneration process (Fig. 1). Steam injection is a technique which can increase the ability of a plant to generate extra power without burning extra fuel and requiring moderate capital investment. In its most basic form, steam injection works by increasing the global mass flow rate through the gas turbine without increasing the mass of air compressed. Please click Additional Files below to see the full abstract

Energy recovery from effluents of supercritical water oxidation reactors

Producción CientíficaSupercritical water oxidation (SCWO) reactors can process waste effluents achieving high conversions, but the required extreme pressure and temperature operational conditions entail high-energy operational expenditure. SCWO has the potential to be considered a clean energy generation process, as the process effluent is a high temperature, high pressure stream with a high enthalpy content that can be converted to heat and shaft work. This ensures the self-sustained reaction and can generate excess shaft power to drive both the high-pressure pump and the air compressor. On the contrary, an efficient heat and power recovery from SCWO reactors outlet streams using conventional procedures presents several problems. First, Rankine cycles impose indirect heat transfer to the working fluid and are unable to recover the pressure energy and second, direct expansion of the effluents entails costly development of specific, efficient expansion equipment. In this work, we investigate the options for energy recovery of SCWO reactors coupled with commercial gas turbines (GT). SCWO outlet streams are mainly composed of water, nitrogen and carbon dioxide. These operating values nearly resemble the well-known and already-implemented GT steam injection procedures. The temperature of the flue gases (approx. 500 °C) and the direct shaft work usage offers adequate energy integration possibilities for both feed preheating and compression. The wide range of commercially available GT sizes enables process scaling.Ministerio de Economía, Industria y Competitividad - FEDER (Proyect CTQ2013-44143-R

A techno-economic assessment of the potential for combining supercritical water oxidation with ‘in-situ’ hydrothermal synthesis of nanocatalysts using a counter current mixing reactor

A combined process of supercritical water oxidation (SCWO) and supercritical water hydrothermal synthesis (SCWHS) in a continuous counter current reactor is reported. Acrylic acid was used as a model unsaturated carboxylic acid compound and the effects of the reaction temperature, residence time, oxidant ratio and acrylic acid concentration on chemical oxygen demand (COD) were all investigated. Two different experimental configurations for oxidant delivery were carried out in ‘pre-heated’ and ‘non-preheated’ oxidant configurations. With a stoichiometric excess of 100% oxygen, COD reduction levels of 80% (non-preheated) and 15% (preheated) were achieved with very short residence times. SCWHS was achieved through the addition of small amounts of various soluble metal salts in the cold upflow resulted in nanoparticles forming which increased the reaction rate and hydrothermal oxidation efficiency. The addition of small amounts of chromium nitrate (>5mM) results in nearly 100% COD reduction at 380 °C and residence times of 0.75 s. The potential economic benefits of combining the two processes together, in the different configurations, were also evaluated

Analysis of the energy flow in a municipal wastewater treatment plant based on a supercritical water oxidation reactor coupled to a gas turbine

Producción CientíficaBiological municipal wastewater treatments lead to high sludge generation and long retention times, and the possibilities for recovery of the energy content of the input waste stream are very limited due to the low operating temperature. As an alternative, we propose a sequence of exclusively physicochemical, non-biological stages that avoid sludge production, while producing high-grade energy outflows favoring recovery, all in shorter times. Ultrafiltration and evaporation units provide a front-end concentration block, while a supercritical water oxidation reactor serves as the main treatment unit. A new approach for energy recovery from the effluent of the reactor is proposed, based on its injection in a gas turbine, which presents advantages over simpler direct utilization methods from operational and efficiency points of view. A process layout and a numerical simulation to assess this proposal have been developed. Results show that the model process, characterized with proven operating parameters, found a range of feasible solutions to the treatment problem with similar energy costs, at a fast speed, without sludge production, while co-generating the municipality’s average electricity consumption.Ministerio de Ciencia e Innovación - (Grant RTI2018- 097456-B-100

Supercritical water oxidation for energy production by hydrothermal flame as internal heat source. Experimental results and energetic study

Producción CientíficaThe cooled wall reactor has been modified by adding an additional upper outlet of products at 500–700 °C to improve energy recovery and make possible energy generation with the supercritical water oxidation of different waste. Experimental and modeling results of the performance of this new reactor configuration are presented as well as a theoretical analysis of the energy recovery of the reactor compared to other supercritical water oxidation reactors. Different flow distributions were tested to find the best elimination conditions. Total organic carbon removal over 99.99% was obtained at room injection temperatures, when the fraction of products leaving the reactor in the upper effluent is lower than 70% of feed flow. The performance of the reactor was tested with the oxidation of a recalcitrant compound such as ammonia. Removals higher than 99% of were achieved at temperatures near 700 °C. The behavior of the reactor working with feeds with up to 2.5% wt Na2SO4 could be injected in the reactor without plugging problems. Upper effluent always presented a concentration of salt lower than 30 ppm. Theoretical energetic analysis shows that the performance of this reactor is superior to other designs obtaining a maximum power efficiency of 27% (0.339 kW/kg-feed).Ministerio de Economía, Industria y Competitividad - FEDER (Proyect CTQ2013-44143-R

Estudio de utilización de fármacos hipotensores en pacientes hipertensos pertenecientes al policlínico “Santa Clara”

Introducción: Los estudios de utilización de medicamentos (EUM) constituyen la herramienta que nos permite la evaluación y posterior diseño de estrategias de intervención para la utilización adecuada de medicamentos. En Cuba, a pesar de ser la hipertensión arterial una enfermedad muy frecuente, los estudios de utilización son escasos.Objetivo: Caracterizar la utilización de fármacos hipotensores en la población perteneciente al policlínico Santa Clara en el período de septiembre del 2012 hasta mayo del 2013.Diseño Metodológico: Se realizó un estudio de utilización de medicamentos de tipo indicación-prescripción, de corte transversal. El universo  estuvo conformado por todos los pacientes hipertensos del consultorio 16-19, que pertenecen a su vez al policlínico Santa Clara, siendo un total de 167 pacientes, de quienes se tomó el tratamiento prescrito según certificados de medicamentos presentes en la farmacia. Las variables de estudio fueron: edad, sexo, diagnóstico de hipertensión y tratamiento.Resultados: el grupo que más prescripción de fármacos presentó fueron los mayores de 60 años, donde los fármacos antihipertensivos más utilizados fueron la hidroclorotiazida. La mayor cantidad de unidades prescritas perteneció a la hidroclorotiazida, donde 99 pacientes se encontraron en dosis media.Conclusiones: Los fármacos hipotensores de mayor prescripción médica corresponden al grupo de los pacientes mayores de 60 años. Los fármacos antihipertensivos más utilizados fueron la hidroclorotiazida, el captopril y el atenolol, según el orden de frecuencia. La mayor cantidad de unidades de medicamentos que se prescriben pertenecieron a la hidroclorotiazida, el atenolol y el enalapril encontrándose en prescripción de dosis media.ABSTRACTIntroduction: Drug utilization studies (DUS) are the tool that allows the evaluation and design of intervention strategies for the appropriate use of medicines Objective: To characterize the use of antihypertensive drugs in the population belonging to the Santa Clara clinic in the period September 2012 to May 2013. Materials and Methods: A drug use-prescription indication, cross-section study was performed. The universe consisted of all hypertensive patients in the office 16-19 (167 patients)Results: The patients that had more drugs prescribed were the over 60 year’s group and the most commonly used antihypertensive medications was hydrochlorothiazide. The most units prescribed drug was hydrochlorothiazide, where 99 patients were found in mean doseConclusions: The most commonly used antihypertensive medications were hydrochlorothiazide, captopril and atenolol

Understanding bottom-up continuous hydrothermal synthesis of nanoparticles using empirical measurement and computational simulation

Continuous hydrothermal synthesis was highlighted in a recent review as an enabling technology for the production of nanoparticles. In recent years, it has been shown to be a suitable reaction medium for the synthesis of a wide range of nanomaterials. Many single and complex nanomaterials such as metals, metal oxides, doped oxides, carbonates, sulfides, hydroxides, phosphates, and metal organic frameworks can be formed using continuous hydrothermal synthesis techniques. This work presents a methodology to characterize continuous hydrothermal flow systems both experimentally and numerically, and to determine the scalability of a counter current supercritical water reactor for the large scale production (>1,000 T·year–1) of nanomaterials. Experiments were performed using a purpose-built continuous flow rig, featuring an injection loop on a metal salt feed line, which allowed the injection of a chromophoric tracer. At the system outlet, the tracer was detected using UV/Vis absorption, which could be used to measure the residence time distribution within the reactor volume. Computational fluid dynamics (CFD) calculations were also conducted using a modeled geometry to represent the experimental apparatus. The performance of the CFD model was tested against experimental data, verifying that the CFD model accurately predicted the nucleation and growth of the nanomaterials inside the reactor