Enhancement of CO2 capture in limestone and dolomite granular beds by high intensity sound waves

The calcium looping (CaL) process, based on the calcination/carbonation of CaCO3 at high temperatures, has emerged in the last years as a potentially low cost technology for CO2 capture. In this work, we show that the application of high intensity sound waves to granular beds of limestone and dolomite in a CaL reactor enhances significantly their multicycle CO2 capture capacity. Sound waves are applied either during the calcination stage of each CaL cycle or in the carbonation stage. The effect of sound is to intensify the transfer of heat, mass and momentum and is more marked when sound is applied during calcination by promoting CaO regeneration. The application of sound would allow reducing the calcination temperature thereby mitigating the decay of capture capacity with the number of cycles and reducing the energy penalty of the technology.Ministerio de Economia y Competitividad CTQ2014-52763-C2-2-

Adelante / Endavant

Séptimo desafío por la erradicación de la violencia contra las mujeres del Institut Universitari d’Estudis Feministes i de Gènere "Purificación Escribano" de la Universitat Jaume

Optimización de la captura de co2 mediante lechos fijos y fluidizados de adsorbentes basados en calcio a escala de laboratorio

El cambio climático es un problema mundial que cada vez nos preocupa más a todos. La principal causa del calentamiento global son los gases de efecto invernadero, siendo el CO2 uno de los más importantes. Decenas de Gigatoneladas de este gas son emitidas cada día a la atmósfera. Este trabajo se focaliza en la técnica “Ca-Looping” cuyo objetivo es la captura de CO2 emitido en procesos industriales mediante su quimisorción en un lecho de partículas de CaO a alta temperatura. En la investigación llevada a cabo se ha estudiado la modificación del material (CaO) usado para la captura de CO2 mediante aditivos de mayor estabilidad térmica, se ha comprobado el efecto negativo de la presencia de SO2, se ha visto la reactivación de la muestra gracias al vapor de agua y se han utilizado ondas acústicas de alta intensidad para mejorar la eficiencia de la captura

The Sevilla Powder Tester: A Tool for Measuring the Flow Properties of Cohesive Powders at High Temperatures

Understanding the flowability of cohesive powders at high temperature is of great importance for many industrial applications where these materials are handled at harsh thermal conditions. For instance, the Calcium-Looping (CaL) process, involving the transport, storage and fluidization of limestone powders at high temperature, is being considered nowadays as a promising technology for thermochemical energy storage (TCES) in concentrated solar power plants (CSP). In this context, the High Temperature Seville Powder Tester (HTSPT) is presented in this work as a useful tool to analyze how the flow behavior of cohesive powders changes with temperature. The manuscript reviews the main results obtained so far using this novel apparatus. The change of powder cohesiveness and therefore of powder flowability as depending on temperature, particle size, material properties and nanosilica surface coating is illustrated.España Ministerio de Economía y Competitividad grant number CTQ2017-83602-C2-2-

Nanosilica to improve the flowability of fine limestone powders in thermochemical storage units

Fine powders are the cornerstone of new energy storage solutions to assist concentrated solar power plants. Though, their ability to behave like fluid can be seriously affected at high temperatures. This work investigates the use of nanosilica in fine limestone (calcium carbonate, CaCO) powders to mitigate the promotion of cohesion forces at high temperatures. Experiments were conducted over limestone powder samples with particle sizes around . The analysis was performed monitoring the tensile yield strength as the samples were subjected to different temperatures and consolidation stresses while varying the nanosilica content up until 0.82 wt%. Temperatures reached a maximum of 500 °C (close to the Tamman temperature in limestone), whereas consolidation stresses were increased up to 2 kPa. Results show that nanosilica coating is an efficient solution to inhibit the enhancement of powder cohesiveness at high temperatures and consolidations. A solution that offers better control to smooth the granular flow regimes in production environments.Ministerio de Economía y Competitividad CTQ2017–83602–C2–2–