| 摘要 |
<p>Continuous processes involving counter moving materials, and apparatus for carrying out such processing, are applied to extraction and to the combining of substances. In a continuous extraction process, solid material is introduced into a feeding body 5 leading to one end of an impermeable housing 6 containing a conical screw 7 the pitch of which decreases towards an outlet 2 for solid material. A fluid solvent is injected at a point 3 close to the outlet 2 and follows a helical path 8 to solvent outlet filters 13 below the foot of the feeding body 5. The solid material contains a solute which is to be extracted and is driven and squeezed progressively by the screw 7 which transports the solid material along a substantially linear path to the outlet 2. The effect of the rotation of the screw is to produce a pressure gradient which promotes solvation so that the solvent leaving through the filters 13 contains extracted solute. The respective rates of flow of the solvent and the solid material can be independently controlled and depend on the injection at the point 3 and the rate of rotation of the screw 7. <IMAGE></p> |
