One aerobic and two combined hydrolytic-aerobic processes were set up to investigate the influence of bio-drying on the potential emissions of combustion gases and the quantitative relationships of potential emissions with organics degradation. Results showed that the bio-drying would result in the increase of the HCl and SO2 emissions and potential for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) formation, but the decrease of NO emissions in the combustion. The potential emissions of combustion gases were correlated with organics degradation (correlation coefficient, r=0.67 for HCl, r=0.96 for SO2, r=0.91 for PCDD/Fs and r=-0.60 for NOx). Interestingly, the total emissions of combustion gases based on input waste could be minimized by bio-drying. The bio-drying caused a reduction of NOx emissions but a negligible variation of total emissions of HCl and SO2 as well as the potential for total PCDD/Fs formation. Moreover, the bio-drying could significantly improve the ratio of gas emissions to low heating values. The mixed waste after bio-drying was more favorable for combustion and the combined process with insufficient aeration during the hydrolytic stage was proposed for the bio-drying operation. (C) 2009 Elsevier B.V. All rights reserved.