The simultaneous transfer of heat and mass between water and moist coal gas

Abstract

The Graphical Method of M ickley [3] for the counter current contacting of moist air with water is modified to apply to the system moist coal gas-water, over the range of saturation temperatures 82°F to 180°F. Over this range the Lewis Number h G / k Gs cannot be considered constant and the log mean partial pressure of the non-diffusing gas varies widely from unity. A driving force is derived, which incorporates these variables for use in conjunction with the gas film mass transfer coefficient. This necessitates the use of two equilibrium lines as in the method of L ewis and W hite [5]. Although no suitable data are available for truly counter current flow for the system considered, the method has been applied to test data on a cross flow water-tube condenser. The results are compared with those obtained by the well known method of C olburn and H ougen [1].