As a kind of chemical reactor, the dual-contact-flow absorption tower has been widely used for SO2 absorption in recent years. However, studies on heat transfer characteristics of the absorber have been rarely carried out. There is also lack of an integrated partition map of flow pattern in the dual-contact-flow absorption tower. In this paper, the gas-liquid flow, heat and mass transfer characteristics in the dual-contact-flow absorption tower have been experimentally investigated. Direct observation, probability density function (PDF) and power spectral density function (PSD) methods are comparatively adopted in the flow pattern analysis. The partition map of flow pattern in the dual-contact-flow absorption tower is obtained through integrating a large quantity of experimental data. In addition, empirical formulas of both heat and mass transfer performances have been developed. Application of empirical formulas has also been stated. The research results obtained in the present study can provide guidance for estimating the practical application performance. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.