Conceptual evaluation of an integrated CCU technology based on Na-salts pH swing mineral carbonation

Bagnato, G. and Sanna, A. (2022) Conceptual evaluation of an integrated CCU technology based on Na-salts pH swing mineral carbonation. Journal of CO2 Utilization, 66. ISSN 2212-9820

Full text not available from this repository.

Abstract

This work proposes an alternative indirect pH swing CO2 Capture and Storage by Mineral Carbonation (CCSM) process in order to decrease the energy intensive salts regeneration. In the proposed process, NaHSO4 is used to extract Mg from the mineral ore, which is then carbonated after a pH swing step. The remaining Na2SO4 is then separated from the carbonation solution taking advantage of its low solubility at temperatures close to 0 °C and then regenerated to NaOH and NaHSO4 in three stages. The integrated process that uses both Mg-rich silicates and inorganic wastes, was experimentally proved, and their energy consumption calculated. The final CO2 sequestration capacity was of 77.4% with enhanced recovery of metals in the pH swing step, which could offset the CCSM by about $50/t CO2. The final regeneration step showed a 55% conversion of Na2CO3 to CaCO3 at 120 °C under 3 bar and the conversion rate could be improved further by optimization. The energy consumption estimation without optimisation indicated that the sodium-based process would require about 19.6 GJ/tCO2, which at this stage of development is larger than the optimised Åbo Akademi process (12-15.5 GJ/tCO2), but considerably lower than the University of Nottingham's process (30 GJ/tCO2).

Item Type:
Journal Article
Journal or Publication Title:
Journal of CO2 Utilization
Additional Information:
Export Date: 23 November 2022 Funding details: Heriot-Watt University, HWU Funding text 1: We thank Dr Lorna Eades at the chemistry department - University of Edinburgh for ICP-MS analysis and Georgina Rosair, chemistry department - Heriot-Watt University for the XRD analysis and Dr Mike Styles and Dr Alicja M. Lacinska, BGS, Keyworth, England, for providing the serpentine sample and its XRF characterisation. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. We acknowledge the financial support by the Heriot-Watt University start-up fund .
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1500/1501
Subjects:
ID Code:
179974
Deposited By:
Deposited On:
30 Nov 2022 14:20
Refereed?:
Yes
Published?:
Published
Last Modified:
04 Jan 2023 12:25