GAS-SOLID MASS-TRANSFER IN A ROTATING DRUM

Gas-solid volumetric mass transfer coefficients (k(s)A) were measured in a rotary drum by evaporation of n-decane into dry air from the surf ace of porous solids. The effect of drum rotational speed, N (0.09 to 2.0 min(-1)), solids volume fraction, eta (0.043 to 0.25) and the pres ence of baffles on k(s)A were investigated. In the presence of baffles , k(s)A was independent of eta and higher than in the case of a rollin g bed where no baffles were present. For the rolling bed case, k(s)A i ncreased with increasing eta. Mass transfer in the rolling bed was mod eled based on the particle motion.