| 摘要 |
Small, wet particulate material is effectively dried by adding a hydrophobizing agent to the wet particulate material to coat the surfaces of particulates, and then using a gaseous fluid to mechanically remove water droplets from the surfaces of the particulates. Once on the surface of the particulates, the hydrophobizing reagent makes the particulates relatively more hydrophobic and increases the contact angle between the particulates and water preferably to an angle of 90 degrees or greater. The activity of the hydrophobizing reagent is to repel water. After altering the hydrophobicity of the particulates, the gaseous fluid, which is preferably air under pressure, is directed at mild pressure over the surfaces of the particulates to remove the water. Because the tendency of the hydrophobizing agent is to increase the particulates' tendency to repel water, the water is easily displaced from the surface of the particulates under mild conditions. The process can be used to dewater a wide variety of constituents including coal particles, clays, sulfide minerals, phosphorous compounds, metal oxide minerals, metals and waste sludge. <IMAGE> |
