• Why is the CO2 storage needed?

CO2 storage is a crucial component of the CCUS value chain. Permanently storing the captured CO2 is the essential enabler of large-scale emissions reductions and for “negative emissions” targets. In the Clean Technology Scenario (CTS), the decarbonisation scenario laid down by IEA, CCUS deployment reaches 115 Gt CO2 by 2060, with the 93% permanently stored.

  • Why do we need a pilot? Can we go directly to full-scale?

A pilot plant is a smaller version of how the real plant should look like at commercial scale. The development pathway of a technology requires the intermediate phase of the pilot scale demonstration to collect actual data and experience that will enable a better operation of the full-scale application.

  • Why is enough treating 1% of the flue gases of the cement kiln to demonstrate the technology?

The CLEANKER pilot plant has been designed at a Technology Readiness Level (TRL) equal to 7. It indicates that the system is supposed to be demonstrated in an operational environment reflecting real conditions. Treating just a portion (1%) of the flue gases from the cement plant will effectively provide a useful indication on how the process performs at larger scales.

  • According to which criteria the pilot is expected to prove the technology?

During the experimental test, the demonstrator system will be operated aiming at reproducing the condition at which the process is expected to be carried out at industrial scale. The most interesting parameters to investigate are the solid to gas ratio at the carbonator inlet, the calcination degree of the raw meal exiting the calciner and the CO2 capture performance in such operating conditions. The goodness of this technology will be evaluated according to these results.

  • What is the energy penalty associated to the technology? Is it economically viable?

According to scientific literature which have evaluated several technologies applied to cement plants, the integrated CaL is expected to outperform the conventional MEA CO2 absorption process in terms of energy consumption. The increase in the cost of clinker for the cement producer is expected to increase by 76% compared to the base case.

  • Are there any other examples of such technology around the world?

The CLEANKER CaL demonstrator system is the first of its kind that is based on entrained flow reactors and it is applied to real cement plant flue gases.

  • Is CO2 utilisation a viable alternative to permanent storage? Which are the most promising routes for CO2 utilisation?

The utilisation of CO2 would enable to turn it from a cost or a waste product into an opportunity. Research activity in the field are focused on 4 main areas: (i) direct use of CO2 in the food, beverage and agricultural industries; (ii) mineral carbonation for the production of carbonates; (iii) Conversion into chemicals and fuel.

However nowadays low emission and cost effective CCU applications are still far from commercial scale, and most of them require a significant amount of renewable energy and material inputs (hydrogen, minerals, etc.).