Dissolution of sulphur powder in cutting oil within batch mixing tank using shear mixer

Abstract

The aim of this work is to study influence of operating condition on dissolution of sulphur powder in cutting oil. The mixing time required for a standard configuration tank was measured from rate of sulphur dissolution by using UV Spectrophotometer. Mixing was carried out in a flat bottom cylindrical vessel with a high speed shear mixer. Rotation speeds of the impeller were varied between 300 to 500 rpm and viscosity of lubricating oil @100 ํC were 4.7, 11.2 and 32.0 cSt. (approximately). Temperature under investigation were between 80 to 120 ํC The results showed that the required mixing time was inversely proportional to rotational speed and depended on temperature, viscosity of lubricating oil and melting point of sulphur powder. The optimum mixing condition was impeller rotational speed of 400 rpm at which the shortest mixing time and the lowest mixing energy were employed. The required mixing time can be correlated with various temperature and viscosity each type of base oil. By employing the dimensional analysis, the empirical equation for the mass transfer coefficient was SHt = rRe[superscript 0.37][subscript a] SC[superscript 0.454] whereas 0.465x10[superscript 3] <Rea <22.371x10[superscript 3], 1.711x10[superscript 11] <Sc <374.155x10[superscript 11]