A real soil contaminated by high concentration polychlorinated biphenyl (PCBs) was heated in a tube furnace at various carrier gas flow rate and at various heating rate to investigate their effect on thermal desorption of PCBs in contaminated soil. With the rising of carrier gas flow rate

a slight increase of PCBs removal efficiency (from 93.5% to 95.1%) and toxic equivalency quantity (TEQ) in soil were observed. With increase of the flow rate desorption amount of PCBs was obvious large when it was lower than 400 ml·min-1

then a little chang at >400 ml·min-1

while TEQ of PCBs showed a trend of linear increase with the rising of flow rate. The TEQ of polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/Fs) in treated soil decreased

while in carrier gas a large increase of TEQ of PCDD/Fs especially PCDFs was observed.The removal rate of PCBs in soil showed a significant positive linear relationship with the heating rate. With the rising of heating rate

the removal efficiency of PCBs in soil increased

and the TEQ of PCBs had a little change. The desorption amount of PCBs decreased. The TEQ removal efficiency of PCDD/Fs increased. After thermal desoption there was significant formation of PCDD/Fs while there was TEQ high increase of PCDD/Fs. Generally

the effect of flow rate on the removal efficiency of PCBs in soil was less but on the desorption amount of PCBs was significant. Higher heating rate can make a better removal efficiency of PCBs and lower formation of PCDD/Fs.