The experimental study of bubble size and its distribution and bubble aspect ratio in a dense bubbly flow conditions remains challenging. The present work enunciates the bubble size and its distribution, and bubble aspect ratio in two (air-water) and three-phase (air-water-coal particle) in a counter-current microstructured bubble column with and without surfactant. The effects of dispersed and continuous phase velocity, solid loading, and solid size are investigated. The results show that an increase in the dispersed phase velocity, the particle concentration led to a rise in Sauter mean bubble diameter, while, it is decreased with an increase in the continuous phase velocity and particle size. The aspect ratio of the bubble decreases as the Eotovos number increases. Bubble size distributions follow the log-logistic cumulative distribution function. Bubbles in the present system are plotted in the grace diagram, indicating that the bubbles cover both the spherical and ellipsoidal shape regimes. A generic empirical correlation is proposed for the Sauter mean bubble diameter and distribution function parameters in terms of operating conditions and physical properties of the system. Experimental data and correlations from the literature and this study were compared with the results of the proposed correlation.