Apparatus for separating and classifying finely divided solid materials

Claim 1

IN COMBUSTION, A PLURALITY OF U-BEND TUBE ELEMENTS IN SERIES EACH ARRANGED TO HOLD A MASS OF FINELY DIVIDED SOLIDS BY GRAVITY, A CONTINUOUS GAS CONDUIT CONNECTING SAID TUBES IN SERIES AND TO A SOURCE OF GAS SUPPLY, SAID CONDUIT INCLUDING AN UPSTANDING VERTICAL SETTLER PORTION ABOVE THE OUTLET LEG OF EACH OF SAID TUBES FOR ELUTRIATING AND CLASSIFYING SAID SOLIDS, SAID UPSTANDING SETTLER PORTIONS BEING RESPECTIVELY OF LARGER AND LARGER DIAMETER DOWN STREAM FROM SAID GAS SOURCE, AND WHEREIN THE SETTLER PORTIONS WHICH ARE OF SMALLEST DIAMETER ARE SHORTENED TO AN EFFECTIVE LENGTH NOT EXCEEDING 15 TIMES THEIR DIAMETER EACH BY AN OUTLET CONNECTION INSERTED DOWNWARDLY INTO SAID SETTLER PORTIONS THROUGH THE UPPER ENDS THEREOF, AND MEANS FOR MECHANICALLY VIBRATING ALL SAID TUBES TO BREAK UP COHESION OF PARTICLES AND FACILITATE SEPARATION BY GRAVITY OF SUCCESSIVELY SMALLER SIZED PARTICLES IN SUCCESSIVE TUBE AND SETTLER ASSEMBLIES.