초록 ▼

A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the di

A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the discharge of a thickened slurry stream. Magnetic particles in the slurry are attracted to, and slide down, magnetic rods within the container. The slurry is thus separated into magnetic concentrate and clarified slurry. Flow control means can be used to control the ratio of the rate of magnetic concentrate to the rate of clarified slurry. Feed control means can be used to control the rate of slurry feed to the slurry inlet.

대표청구항 ▼

What is claimed is: 1. A method of continuously separating a slurry comprising magnetic particles into a clarified stream and a thickened stream consisting essentially of the steps of: a) providing a substantially vertical magnetic separator comprising a container having a top portion and a bottom

What is claimed is: 1. A method of continuously separating a slurry comprising magnetic particles into a clarified stream and a thickened stream consisting essentially of the steps of: a) providing a substantially vertical magnetic separator comprising a container having a top portion and a bottom portion, generating at least one gradient magnetic field within said container and disposed in a substantially vertical orientation, providing an overflow outlet on the top portion of said container, providing an underflow outlet on the bottom portion of said container, and providing at least one slurry inlet on said container disposed to introduce a flow of slurry feed between said overflow outlet and said underflow outlet; b) introducing a continuous flow of feed slurry, said feed slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles into said at least one slurry inlet, wherein said feed slurry is characterized by a concentration of magnetic particles therein; c) withdrawing a continuous flow of overflow slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles from said overflow outlet, wherein said overflow slurry is characterized by a concentration of magnetic catalyst particles therein which is less than the concentration of magnetic catalyst particles in the feed slurry; and d) withdrawing a continuous flow of underflow slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles from said underflow outlet, wherein said underflow slurry is characterized by a concentration of magnetic catalyst particles therein which is greater than the concentration of magnetic catalyst particles in the feed slurry. 2. A method of continuously separating a slurry comprising magnetic particles into a clarified stream and a thickened stream consisting essentially of the steps of: a) providing a substantially vertical magnetic separator comprising a container having a top portion and a bottom portion, at least one magnetic rod mounted fixedly within said container and disposed in a substantially vertical orientation, an overflow outlet on the top portion of said container, an underflow outlet on the bottom portion of said container, and at least one slurry inlet on said container disposed to introduce a flow of slurry feed between said overflow outlet and said underflow outlet; b) introducing a continuous flow of feed slurry, said feed slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles into said at least one slurry inlet; c) withdrawing a continuous flow of overflow slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles from said overflow outlet, wherein said overflow slurry is characterized by a concentration of magnetic catalyst particles therein which is less than the concentration of magnetic catalyst particles in the feed slurry; and d) withdrawing a continuous flow of underflow slurry comprising Fischer-Tropsch liquid containing waxes and magnetic catalyst particles from said underflow outlet, wherein said underflow slurry is characterized by a concentration of magnetic catalyst particles therein which is greater than the concentration of magnetic catalyst particles in the feed slurry. 3. The method of claim 2, wherein the magnitude of the moments of said magnetic particles are greater or equal to 1 emu/gm. 4. The method of claim 2, wherein said at least one magnetic rod is a permanent magnet. 5. The method of claim 2, wherein said at least one magnetic rod is made from one of carbon steel and ferritic stainless steel and is magnetized by an external field. 6. The method of claim 2, further comprising producing a magnetic field which is substantially transverse to the length dimension of the at least 1 magnetic rod, using an energizing device chosen from the group consisting of electromagnets, superconducting magnets, and permanent magnets. 7. The method of claim 2, further comprising adjusting the ratio of the flow rate of underflow slurry to the flow rate of overflow slurry emanating from the magnetic separator. 8. The method of claim 2, wherein the overflow slurry is passed through a secondary separator, wherein said overflow slurry is processed to produce a product stream which is characterized by a concentration of particles which is less than the concentration of magnetic particles in said overflow slurry. 9. The method of claim 8, wherein said secondary separator comprises a high gradient magnetic separator, wherein a continuous flow of overflow slurry is periodically introduced into said high gradient magnetic separator having an applied magnetic field wherein magnetic particles are removed and retained in said high gradient magnetic separator and from time to time removed by back-flushing with said applied magnetic field de-energized. 10. The method of claim 8, wherein said secondary separator is a second continuous magnetic separator. 11. The method of claim 2, wherein said magnetic catalyst particles are at least one of iron, cobalt and nickel. 12. The method of claim 2, wherein the continuous flow from the underflow outlet passes through a demagnetization apparatus. 13. The method of claim 2, wherein the magnetic catalyst particles have diameters less than 500 micrometers. 14. The method of claim 2, wherein the feed slurry has a solids content less than 50 wt. %.