Minerals for Sustainable COst and energy efficient chemical looping combUstion Technology

Mineral Scout is a project focusing on locating mineral sources which can be possible candidates for the new and promising chemical looping combustion technology. There exist several concepts for this technology which all have shown promising results due to the inherent CO2 separation making it suitable for combustion with low cost for CO2 capture. The technology is based on oxygen carriers transporting oxygen between the air and fuel. The oxygen carrier materials that are most suitable are materials that easily and fast can take up oxygen by getting oxidized, like Fe, Mn, Cu and Ni and mixture of these. Natural mineral like ilmenite, a Fe-Ti-O based material, has already been tested but do not give full combustion due to thermodynamic limitations. Differ ent Mn-Fe, Cu-Fe, and Fe-Mn mixed oxides have been tested showing very good performance and full combustion. Natural minerals with similar compositions will in this project be searched and tested in order to evaluate their performance and strength under o perational condition. The project is a cooperation between Stiftelsen SINTEF (NO) - Cambridge University (UK) - Center for Research and Technology Hellas (GR)- National Technical University of Athens (GR) - Institute for Chemical Processing of Coal (PO).

The SCOUT project main objective now is to introduce Carbon Capture and Storage (CCS) to reduce the CO2 emissions from fossil based power plants. Chemical Looping Combustion technology is such a technology and is based on an oxygen carrier material which is oxidized in an air reactor (oxygen uptake from air) and reduced in a fuel reactor (oxygen released/delivery to the fuel), and a reactor system in which this cycling can be performed continuously. Usually a dual fluidized bed reactor is envisaged for CL C in which the oxygen carrier powders are separated from the air stream in a cyclone bringing the powders further safely, through a loop-seal, to the fuel reactor where the oxygen carrier combust the fuel. This technology therefore gives an inherent CO2 s eparation, giving very low CO2 capture cost and high efficiency. The results so far using ilmenite as oxygen carrier in the 100kW test rig shows an extra oxygen need from ASU of 15-20 % to obtain full conversion. The success (low efficiency penalty) of th is technology for use with coal is based on having a material that have sufficient low cost and can give full combustion of the gas meaning no need for ASU unit. The aim of this proposal is therefore to investigate several new cheap mineral sources with C LOU composition towards the critical CLC properties needed for achieving full combustion and enhanced coal gasification. New promising minerals sources found will be introduced for partners in the CLC community.