The research program of the BackCap project is structure in five Work Packages. Two WPs are mainly focus to obtain experimental information. For this purpose, the performance of different sorbent will be tested at different scales (from laboratory to TRL 4-5). This information will be used for modelling purposes. A multi-scale modelling approach is adopted in BackCap so that decisions at system level can have an impact in setting performance targets for reactors and materials. Also, in reverse: the impact of reaction properties and barriers identified at fundamental levels can be assessed from a system/cost perspective only with adequate multiscale model descriptions of the full system. In addition, techno-economic studies will be performed in WP5 to evaluate the costs of the BackCap process. There will be also modelling activities of the process integrated in particular grid scenarios of the future, as well as benchmarking exercises against competing process alternatives supplying similar services (i.e. Power-to-Fuel-to-Power options currently under development in other projects in Europe and worldwide and other back-up system as natural gas turbines).

WP1: Coordination, management and dissemination

WP1 is dedicated to the coordination and management of the BackCap project and the dissemination of project results. Specific objectives are:

  • To provide effective coordination of the technical WPs.

  • To ensure that the RFCS reporting requirements are fully fulfilled.

  • To engage partners in the dissemination of results and facilitate interaction with other projects in the fields of CCUS.

  • To create and maintain the project webpage and other social media tools.

WP2: Kinetic and material studies for reactor design

WP2 concentrates the more fundamental research needed to study the different reaction steps in the BackCap process (carbonation of Ca(OH)2 in different aggregation modes, calcination of carbonated materials and hydration of CaO) with a special focus on the attainment of scalable kinetic information and related material characterization works. The following specific objectives are proposed for this WP:

  • To experimentally investigate the carbonation reaction of Ca(OH)2 and derive experimental data under relevant conditions and aggregation modes.

  • To experimentally investigate the calcination reaction of partially carbonated solids resulting from Ca(OH)2 carbonation.

  • To experimentally evaluate the effect of the partial hydration of the sorbent on CO2 carrying capacity and reactivity towards carbonation.

  • To experimentally evaluate the loss of sorbent CO2 carrying capacity when cycling the material between Ca(OH)2, CaO and CaCO3.

  • To tune gas-solid reactor models to derive kinetic parameters and provide support to the reactor and process modeling tasks of WP4.

WP3: Experimental testing in a TRL4-5 entrained carbonator pilot system

WP3 focuses on a comparative investigation of the CO2 capture performance of different Ca(OH)2 qualities and reaction environments in industrially relevant entrained flow reactor conditions at the (TRL4-5) pilot test rig at USTUTT. Since the most likely gas-solid contacting mode for the BackCap concept will be an entrained bed system. Moreover, this WP focuses on the sorbent regeneration step (including the calcination of the carbonated sorbent and the hydration of the calcined sorbent). Around 350 h of operation are expected in this facility. This task involves the following specific objectives:

  • Identification of optimal carbonation conditions and quantification of CO2 capture performance in different entrained flow carbonation conditions using fresh and cycled hydrated lime samples from CAR.

  • Determination of achievable carbonation conversion under relevant entrained flow reactor conditions.

  • Investigation and identification of favorable calcination and hydration conditions to regenerate spent sorbents, maintaining a high reactivity (towards carbonation, gas-solid high temperature hydration or low temperature water hydration).

  • Investigation on cyclic carbonation/calcination/hydration of sorbent samples from the pilot and their loss in reactivity (i.e. when hydration is not complete).

  • Provision of data for model development and simulation validation in WP4.

WP4: Reactor and process modeling

This work package focusses on the development of different models (reactor to process level) to provide quantitative descriptions of all relevant unit operations and reaction stages affecting the performance of different variants of the BackCap process.

  • To develop integral reactor models for the carbonation of Ca(OH)2 powders in entrained mode and cyclone-type reactors.

  • To adapt existing oxy-calciner models to the characteristics of the carbonated materials evolved in the BackCap carbonator.

  • To develop full multi-scale process model frameworks integrating information at particle, reactor and thermal integration levels, providing the basis for the full-scale studies and economic analyses in WP5.

WP5: Full scale studies/Economic analysis

The aim of this work package is to perform full-scale plant studies and a basic economic analysis of the BackCap process. As basis for the tasks related, the amortized “La Pereda” power plant (50 MWe owned by HUNOSA in Spain) will serve as an exemplary power plant to be retrofitted to adapt to a context of backup power requirements, in a power grid with a large share of renewable energy. The specific objectives of this work package are:

  • To estimate the cost and the key performance indicators of the BackCap process today and in a 2030 scenario.

  • To carry out a benchmark of the BackCap process against alternative competing process for similar back-up power provision services (i.e. power-to-fuel-to-power and gas turbines).

This project has received funding from the European Union’s Research Fund for Coal and Steel (RFCS) Under grant agreement No 101034000

Disclaimer: The content of this website reflects only the author’s view and the Commission is not responsible for any use that may be made of the information it contains.





Dr. Borja Arias
CO2 Capture group, Carbon Science and Technology Institute (INCAR – CSIC)
C/ Francisco Pintado Fe, 26, 33011 OVIEDO, Spain