(620f) Biomass Gasification/Combustion Using NiO As an Oxygen Carrier in Clc Process

Heavier hydrocarbon fuels such as petroleum residue (liquid), solid fuel such as coal and biomass is considerably abundant and cheaper than natural gas. Considering the facts several research groups recently being devoted their efforts to adapt solid fuels such as petroleum coke, coal and biomass in CLC.  This process considers in situ gasification of solid fuel to produce and burn the produced syngas inside the fuel reactor of a CLC process.  In this option the solid-solid reaction between the solid fuel and the solid oxygen carrier is likely to be the rate limiting step. The agricultural and municipal wastes have long been considered as potential major source of renewable energy with zero net CO₂ emissions.  The use of biomass as fuel, in conjunction with CLC, offers the additional possibility of delivering negative CO₂emissions.  To accomplish this, a possible approach is to gasify the solid fuel producing syngas which can be subsequently burned inside the same fuel reactor of a CLC process. This approach has the following main advantages: (i) eliminates extra units for solid gasification and (ii) circumvents the dilution of the syngas with nitrogen.  

This communication reports the investigation of integrated biomass gasification and chemical-looping combustion (CLC) process for CO₂ capture from a biomass based power generating stations.  In this regard, a lanthanum modified Ni/La-γAl₂O₃ material is prepared and studied as an oxygen carrier. Temperature programmed reduction characterization of Ni/La-γAl₂O₃ shows that the presence of La enhances the reducibility of the oxygen carrier by influencing the metal-support interactions helping the formation of reducible nickel species. The integrated biomass gasification and CLC experiments are developed in a CREC Fluidized Riser Simulator using glucose as model compound for biomass.  The product analysis shows that CO₂ and H₂O as major products indicating that the combustion of the biomass gasification products can be achieved using an oxygen carrier materials.

Keywords:  Biomass gasification, CO₂capture,  NiO oxygen carrier.

Acknowledgement: We would like to gratefully acknowledge the support provided by King Abdulaziz City for Science and Technology (KACST) through KACST-TIC on CCS at KFUPM.