TITLE: Gas/Slurry Flow in Coal Liquefaction Processes (Fluid Dynamics in 3-Phase Flow Columns). Quarterly Technical Progress Report, October 1, 1979-31 December 1979.

AUTHOR: D. H. S. Ying;   R. Sivasubramanian;   E. N. Givens.

INST.  AUTHOR: Air Products and Chemicals, Inc., Allentown, PA.

SPONSOR: Department of Energy, Washington, DC.

LANGUAGE: English

PUB.  TYPE: Technical Report

PUB.  COUNTRY: United States

SOURCE: Department of Energy [DE],  Jan 80,  101p.

ABSTRACT:

This work is a continuation of studies on the fluid dynamics of 3-phase flow to support the design of 6000 T/D dissolver in the SRC-I demonstration plant. Gas holdup in gas/liquid and gas/liquid/solid systems were investigated both in the presence and absence of liquid flow. The variables studied were: particle size (20/30 mesh and less than 100 mesh), solids concentration (0, 5, 11 and 12.7 lbs/ft exp 3 ), liquid velocity (0 to 0.05 ft/sec) and gas velocity (0.036 to 0.368 ft/sec). Gas holdup is found to be independent of liquid velocity which agrees with most investigators. At low superficial gas velocities (up to 0.10 ft/sec), the presence of solids did not change the gas holdup. However, at high gas velocities, only the presence of fine particles (less than 100 mesh) decreased holdup. The most severe reduction in holdup (13.9%) occurred at the highest gas velocity (0.368 ft/sec) and the highest solid concentration (11 lb/ft exp 3 ). The gas holdup data can be reasonably described by the correlation of Yoshida and Akita, except at the high concentration (11 lb/ft exp 3 ) of fine particles (less than 100 mesh).  Liquid dispersion experiments were conducted in gas/liquid and gas/liquid/solid systems. All the three-phase experiments were done with 20/30 mesh sand. The variables studied were: liquid velocity (0.01 to 0.05 ft/sec), gas velocity (0 to 0.327 ft/sec) and solids concentration (5 and 20 lbs/ft exp 3 ). Liquid axial dispersion coefficients were independent of liquid velocity. Increasing gas velocity, however, increased the liquid dispersion coefficient. The presence of solid particles decreased the axial dispersion coefficient. Most of the correlations in the literature do not account for the presence of solids and fail to predict axial dispersion coefficients. The results indicate the need for a correlation that could account for the presence of solid particles. (ERA citation 05:021641)

CONTRACT  NUMBER: AC01-79ET14801