Separation of solids from fluids

Claim 2

A PROCESS FOR THE SEPARATION OF PARTICUALTE SOLIDS FROM ADMIXTURE WITH A FIRST FLUID, COMPRISING PASSING A BODY OF SUCH SOLIDS AND SAID FIRST FLUID INTO A SETTLING ZONE UNDER CONDITIONS THEREIN FOR SETTLING SAID SOLIDS, PASSING A DIFFERENT SECOND FLUID INTO SAID BODY OF SUCH SOLIDS AND SAID FIRST FLUID IN UNIFORM CONTACT THEREWITH AND CONTROLLING THE RATE AND AMOUNT OF FLOW OF SAID SECOND FLUID INTO SAID BODY SO AS TO MAINTAIN SAID SETTLING AND TO RE PLACE SAID FIRST FLUID IN SAID BODY, AND RECOVERING SETTLED SOLIDS IN ADMIXTURE WITH SAID SECOND FLUID FROM SAID SETTLING ZONE SUBSTANTIALLY FREE FROM SAID FIRST FLUID.

Claim 3

IN THE FLUID CATALYTIC CRACKING OF HYDROCARBONS WHEREIN VAPOURS EFFLUENT CONTAINS SUSPENED PARTICLES OF CATALYST TOGETHER WITH BY-PRODUCT OIL, WHEREIN SAID BYPRODUCT OIL IS RECOVERED AS A SLURRY WITH CATALYST AS A RESULT OF PROCESSING OF SAID EFFLUENTS, THE SAID BY-PRODUCT OIL BEING HIGH COKE-YIELDING UNDER THE CONDITIONS OF SAID CRACKING AND THEREBY RENDERING THE SAID SLURRY UNSUITABLE FOR RECYCLE TO THE CRACKING STEP, THE IMPROVEMENT COMPRISING PASSING SAID SLURRY INTO A SETTLING ZONE AND THEREIN ALLOWING CATALYST PARTICLES TO SETTLE BY GRAVITATION, PASSING A FLUSHING OIL LOW COKE-YIELDING UNDER CONDITIONS OF SAID CRACKING, LATERALLY AND UPWARDLY INTO SAID SLURRY AT AN INITIAL LOW POINT THEREIN SO AS TO EFFECT UNIFORM CONTACT OF FLUSHING OIL WITH SAID SLURRY ATA RATE OF VERTICAL LINEAR FLOW NOT PRECLUDING SETTLING OF CATALYST AND PROVIDING FOR RECOVERY OF CATALYST AS A SLURRY WITH SAID FLUSHING OIL, SEPARATING SETTLED CATALYST SUBSTANTIALLY FREE FROM SAID HIGH COKE-YIELDING OIL AS A SLURRY WITH SAID FLUSHING OIL, AND PASSING THE LAST SAID SLURRY TO THE CRACKING SYSTEM FOR REUSE OF SAID CATALYST THEREIN.

Claim 4

IN THE FLUID CATALYTIC CRACKING OF HYDROCARBONS WHEREIN VAPOURS EFFLUENT CONTAINS SUSPENED PARTICLES OF CATALYST TOGETHER WITH BY-PRODUCT OIL, WHEREIN SAID BYPRODUCT OIL IS RECOVERED AS A SLURRY WITH CATALYST AS A RESULT OF PROCESSING OF SAID EFFLUENTS, THE SAID BY-PRODUCT OIL BEING HIGH COKE-YIELDING UNDER THE CONDITIONS OF SAID CRACKING AND THEREBY RENDERING THE SAID SLURRY UNSUITABLE FOR RECYCLE TO THE CRACKING STEP, THE IMPROVEMENT COMPRISING PASSING SAID SLURRY INTO A SETTLING ZONE AND THEREIN ALLOWING CATALYST PARTICLES TO SETTLE BY GRAVITATION, PASSING A FLUSHING OIL LOW COKE-YIELDING UNDER CONDITIONS OF SAID CRACKING, LATERALLY AND UPWARDLY INTO SAID SLURRY AT AN INITIAL LOW POINT THEREIN SO AS TO EFFECT UNIFORM CONTACT OF FLUSHING OIL WITH SAID SLURRY ATA RATE OF VERTICAL LINEAR FLOW NOT PRECLUDING SETTLING OF CATALYST AND PROVIDING FOR RECOVERY OF CATALYST AS A SLURRY WITH SAID FLUSHING OIL, SEPARATING SETTLED CATALYST SUBSTANTIALLY FREE FROM SAID HIGH COKE-YIELDING OIL AS A SLURRY WITH SAID FLUSHING OIL, AND PASSING THE LAST SAID SLURRY TO THE CRACKING SYSTEM FOR REUSE OF SAID CATALYST THEREIN.