Patent EA-001233-B1 (EA)
Title: Method for separating liquid from a slurry and process for the preparation of hydrocarbons
Inventor: ENGEL DIRK COENRAAD
IPC: C10G31/09
Filed: 1997-02-27
Abstract: 1. A method for separating in a chemical process liquid from a slurry of solid catalyst particles active in the chemical process and liquid contained in a vessel in the presence of a gas, the vessel being a three-phase slurry reactor and the gas being at least one gaseous reactant in the chemical process while the liquid is a product produced in the chemical process, which comprises degasifying the slurry and passing the degasified slurry through a cross-flow filter, and separating the degasified slurry into the liquid and a concentrated slurry. 2. A method as claimed in claim 1, wherein the slurry is degasified in a device in which separation takes place in a centrifugal field, preferably a hydrocyclone. 3. A method as claimed in claim 1, wherein the slurry is degasified by a continuous disengagement method, preferably a continuous disengagement method which comprises continuously introducing slurry into a substantially vertical standpipe which is partly filled with slurry, continuously withdrawing gaseous compounds from the upper part of the standpipe not containing slurry, and continuously withdrawing degasified slurry from the lower part of the standpipe, wherein the linear velocity of withdrawing degasified slurry from the standpipe is lower than the upward linear velocity of the gaseous compounds present in the slurry. 4. A method as claimed in any one of the preceding claims, wherein the filter is located outside the vessel. 5. A method as claimed in claim 4, wherein at least one pump is applied, and wherein upstream of the pump, the slurry is degasified, and wherein at least part of the concentrated slurry is returned to the vessel. 6. A method as claimed in any one of the preceding claims, wherein the degasified slurry is separated into a first stream having a low concentration of solid particles and a second stream having a high concentration of solid particles, and the first stream is sent to the filter. 7. A method as claimed in claim 6, wherein the slurry is separated into a first and second stream in a hydrocyclone. 8. A process for the preparation of heavy hydrocarbons, which process comprises contacting a synthesis gas in a reactor vessel with a slurry of solid catalyst particles and a liquid, thereby producing heavy hydrocarbons, and separating the liquid containing heavy hydrocarbons from the slurry by the method as claimed in any one of the preceding claims, and wherein the filter preferably is located outside the reactor vessel and the separation preferably is carried out at substantially the same pressure as applied in the reactor vessel. 9. A process as claimed in claim 8, wherein the average residence time of catalyst-containing slurry outside the reactor vessel is kept to less than 10 minutes, preferably less than 1 minute, or wherein at least the part of the slurry that is sent to the filter, is cooled, preferably to a temperature from 5 to 75 degree C below reaction temperature. 10. Installation comprising at least a three-phase slurry reactor, a degasifying unit and a cross-flow filter unit and optionally a standpipe and a pump, for carrying out a method or process as claimed in any one of the preceding claims 1-9.