Calcination under low CO2 pressure enhances the Calcium Looping performance of limestone for thermochemical energy storage

The Calcium Looping performance of limestone for thermochemical energy storage has been investigated under novel favorable conditions, which involve calcination at moderate temperatures under CO2 at low pressure (0.01 and 0.1 bar) and carbonation at high temperature under CO2 at atmospheric pressure...

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Detalles Bibliográficos
Autores: Sarrión Aceytuno, Beatriz, Perejón Pazo, Antonio, Sánchez Jiménez, Pedro Enrique, Amghar, Nabil, Chacartegui, Ricardo, Valverde Millán, José Manuel, Pérez Maqueda, Luis Allan
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2021
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/116269
Acceso en línea:https://hdl.handle.net/11441/116269
https://doi.org/j.cej.2020.127922
Access Level:acceso abierto
Palabra clave:Concentrated solar power
Limestone
Thermochemical energy storage
Calcium-Looping
Low CO2 pressure
Descripción
Sumario:The Calcium Looping performance of limestone for thermochemical energy storage has been investigated under novel favorable conditions, which involve calcination at moderate temperatures under CO2 at low pressure (0.01 and 0.1 bar) and carbonation at high temperature under CO2 at atmospheric pressure. Calcining at low CO2 pressures allows to substantially reduce the temperature to achieve full calcination in short residence times. Moreover, it notably enhances CaO multicycle conversion. The highest values of conversion are obtained for limestone samples calcined under 0.01 bar CO2 at 765 °C. Under these conditions, the residual conversion is increased by a factor of 10 as compared to conditions involving calcination under CO2 at atmospheric pressure. The enhancement of CaO conversion is correlated to the microstructure of the CaO samples obtained after calcination. As seen from SEM, BET surface and XRD analysis, calcination under low CO2 pressure leads to a remarkable decrease of pore volume and CaO crystallite size. Consequently, CaO surface area available for carbonation in the fast reaction-controlled regime and therefore reactivity in short residence times is promoted.