Abstract:The mix volatiles of biooil steam and noncondensable gases need to be separated by condenser in the consecutive apparatus. Relevant researches about water steam condensational effect with air or N2 were carried out by researchers both at home and abroad. It showed that non-condensable gases can distinctly affect condensational process by reducing local heat transfer coefficient. A system of condensational testing tube was built for pyrolysis volatiles at different temperatures. Volatiles of oiltea camellia produced at 400℃, 500℃ and 600℃ were tested in this system. As a result, local heat transfer coefficients decreased with the increase of condensational process. The values of volatiles at 400℃ were higher than those at 500℃ and 600℃, which showed that the increase of noncondensable gases decreased the heat transfer intensity of volatiles. When experimental data were simulated in Nusselt theoretical model and ffactor model, the result showed that compared with the Nusselt theoretical model, f factor model was more suitable for fitting experimental result of oiltea camellia volatiles produced at 500℃ with the error less than 20W/(m2·K). Exponential decay equations can fit the experimental data of volatiles at 400℃ and 500℃, which brought an assistant reference for biooil condenser design in consecutive pyrolysis apparatus.