Development of an experimental technique for oil recovery during biomass pyrolysis

A new system to collect and analyse some of the condensable products of biomass pyrolysis is developed and tested. Pyrolysis of olive stone, oak pellet, pine pellet and major components of biomass (cellulose, hemicellulose and lignin) is performed by means of a thermogravimetric analysis (TGA). Some of the pyrolysis oil generated during the pyrolysis process condenses on an aluminium ring located in the gas exhaust of the device. The validity and repeatability of the method were shown when a similar oil mass was collected when the test conditions were repeated with the same material. In the biomass experiments, a larger amount of oil was collected from pellet samples, which have the highest cellulose content. This is consistent with the pure component experiments, as avicel cellulose shows the highest depositions. The depositions of the pure components show greater percentage of oil deposited than those of the biomass samples. The results reveal the important influence that the compositions of the biomass and the interactions among its major components have on the composition and quantity in the final deposit. Finally, the differences between deposits from biomass and deposits from mixed components were revealed by an FTIR analysis of the liquid products.