Capsule Transport in Coal Slurry Medium

Abstract

The use of coal slurry instead of water in a coal log pipeline (CLP) is investigated for the first time. This investigation reveals significant differences and possible benefits by using coal slurry instead of water in CLPs. The lift-off velocity, and capsule and total pressure gradients are presented for a 51 mm pipeline using two capsule geometries. The fluid velocity was tested from 1 to 3 m/s, which includes the lift-off velocity of the capsule train. The diameter ratio (k) and specific gravity (S) are held constant at 0.75 and 1.3, respectively. Two capsule lengths were studied corresponding to aspect ratios (a) of 2 and 4. Aluminum-Plexiglas capsules are used to simulate the coal logs. The coal slurry significantly lowered the lift-off velocity, and transported more coal per total pressure gradient than coal logs in water. The capsule pressure gradient was nearly constant over the velocity range investigated. This indicates that the optimal operation velocity range may be much larger for coal slurry compared to water. Further tests and abrasion studies are required to fully assess the potential benefits of using coal slurry.