AbstractThe maximum spoutable bed height of systems of fine glass spheres spouted with water is studied in a flat based, semi‐circular column of 80 mm diameter using glass spheres of diameters 0.300, 0.377, and 0.450 mm.A new correlation is proposed to predict the maximum spoutable bed height in water spouted fine particle systems. The same correlation is suggested for use with air spouted fine particles larger than 0.5 mm. It is concluded that in fine particle systems the jet penetration is significantly lower than that in coarse particle systems. The influence of the column diameter on the maximum spoutable bed height is also decreased significantly compared to coarse particle systems. Data reported in the literature for other water spouted fine particle systems agree with the correlation proposed in this wor