Experimental data is reported on two-phase flow parameters in a 2D packed/unpacked rectangular reactor. This was obtained by different techniques of imaging, laser velocimetry, and pressure drop dynamics, in a 2D transparent rectangular column of large aspect ratio and 2mm gap size. The column was operated in upflow gas–liquid flow with and without packing placed in a structured way. For the imaging studies, a simple-processing technique has been developed, which allowed direct simultaneous measurements of gas volume fraction, liquid–gas interfacial area and bubble size parameters. The time-averaged liquid velocity field, turbulent intensity, and Reynolds stresses were obtained by an LDV technique for two-phase flow in bubbly regime and reactor with and without packing. The experimental results show that the use of packing results in better phase distribution, it increases the range of gas flowrates at which bubbly flow occurs, and decreases backmixing by global recirculation.