Characterisation of products from the pyrolysis of South Australian Radiata Pine

Radiata pine grown in sustainably harvested forests in the mid north of South Australia is a potential source of renewable carbon for local smelting operations. The wood must first be converted into charcoal through pyrolysis. By-products from pyrolysis, including condensate, have value which can be used to offset the cost of producing charcoal and improve the economics of charcoal supply. Pine wood logs were collected from the Wirrabara forest which is near Port Pirie in South Australia. Samples of this wood were pyrolysed at 350, 550 and 750 °C using a kg scale rotary furnace. Pyrolysis products including charcoal and condensate were collected and analysed. The condensate was further treated in a centrifuge to separate the organic ‘bio-oil' fraction from the aqueous pyroligneous acid fraction. The effect of pyrolysis temperature on the properties of the resulting charcoal was in accord with similar work on other wood types. The carbon content and calorific value of the charcoal increased with temperature while the charcoal volatile content decreased. The organic ‘bio-oil' fraction of the condensate increased slightly with temperature but was quite low at between 5 and 8 %. The carbon content and calorific value of the bio-oil increased with temperature from 57 to 60 % and from 25.7 to 26.1 MJ/kg respectively. The potential value of the bio-oil, based on the measured properties is discussed.