The effects of gas sparger types on the operational characteristics of a bubble column (BC) with a rotating-disk mechanical foam-breaker (MFRD), such as foam-breaking, foaming, flow and mass transfer characteristics, were studied. The required critical disk rotational speed, N-c, and liquid hold-up in the foam, phi(L), reflected the foam-breaking behaviour of the MFRD and the foaming behaviour of the BC respectively, which changed depending on the gas sparger type. The dependence of the gas sparger type on the gas hold-up, epsilon(g), was similar to that observed for the volumetric mass transfer coefficient, k(L) a. A comparative investigation of k(L)a with various gas spargers, in terms of the specific power input, also demonstrated the usefulness of the porous sintered glass bead filter as a gas sparger.