Conference Dates

March 8-13, 2009


A test program has been carried out in a pilot-scale (2.5 GJ/h) tunnel furnace to evaluate potential emission levels from combustion of various biomass pyrolysis oil 'cuts'. Two pyrolysis oil cuts were tested: a “whole” oil and a “premium” high moisture (30% H2O) oil, both supplied by Ensyn. A CETC-O designed external mixing air-assisted atomising nozzle originally designed for coal liquid mixtures was used. The oils were preheated to 48 – 52°C. The atomizing air was not preheated and main combustion air preheat was varied from ambient to 120°C. Under steady state operation both pyrolysis oil cuts were found to perform well within the following ranges: O2 4.5 %; CO 45 – 106 ppm and NOx 150 – 250 ppm. The oils were also tested in co-firing mode in which natural gas was added from 10 to 50% of the total heat input. This served to substantially improve the performance of both oil cuts and CO then easily maintained below 50 ppm and total particulates below 50 mg/Nm3. These results were generally independent of natural gas level in the 10 - 50% range and were similar for both cuts of oil.