Innovative oxygen carriers uplifting chemical-looping combustion

Abstract

This paper reports on the main results of the EU-financed project INNOCUOUS (Innovative Oxygen Carriers Uplifting Chemical-Looping Combustion). The project follows a series of successful projects with the aim of developing chemical-looping combustion (CLC) with gaseous fuels rich in methane. The project has included a wide range of experimental and modelling tasks, which included i) extensive screening of spray-dried and impregnated oxygen carriers, ii) production of impregnated and spray-dried oxygen carriers at >100 kg scale, iii) operation of several oxygen carriers at industrial conditions up to 120 kW scale and iv) techno-economic study of the next-scale CLC. One area of focus in the project has been the search for viable oxygen carriers which have low or no Ni. A large portfolio of interesting metal oxide systems has been found. Two oxygen carriers of CaMnxTiyMg1-x-yO3 were successfully produced in larger amounts by spray-drying and an oxygen carrier of Fe2O3/Al2O3 was produced in similar quantity using impregnation. The Ca-based material showed excellent behavior in a 10 kW and 120 kW unit, where complete combustion was achieved. With respect to the aim of replacing the bench-mark Ni-based material the project was thus very successful, as complete combustion has never been achieved in these units using Ni-based material.