Fluidization aid
AssigneeTRW Inc.
InventorEdward F. Brooks
Life of this patent
Estimating the term…
Abstract
Tendrillar carbonaceous material is used as a fluidization aid for fluidized beds. The tendrillar carbonaceous material can be used to fluidize cohesive solids. Further, it can be used to improve fluidization of particulate solids by reducing entrainment, eliminating bubbling, and/or eliminating channelling. The tendrillar carbonaceous material can be a fibrous, particulate carbonaceous material comprising carbon fibers and a ferrous group metal component dispersed throughout the carbon fibers as nodules. The tendrillar carbonaceous material has a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprises an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1.
Claims37
A method for fluidizing a particulate solid in a mixed fluidized bed, the particulate solid having a mean particle size of from about 0.1 to about 200 microns and a particle density of from 0.1 to 8 g/cm.sup.3, the method comprising the steps of:
- (a) combining the particulate solid with tendrillar carbonaceous material in a mass ratio of tendrillar carbonaceous material to particulate solid of from about 1:33 to about 4:1, the tendrillar carbonaceous material having a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprising an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1;
- and
- (b) passing a fluidizing gas through the combined particulate solid and tendrillar carbonaceous material at a sufficient velocity to fluidize the particulate solid and the tendrillar carbonaceous material.
A composition suitable for fluidization in a mixed fluidized bed comprising:
- (a) a particulate solid having a mean particle size of from 0.1 to 200 microns and a particle density of from 0.1 to 8 g/cm.sup.3 ;
- and
- (b) tendrillar carbonaceous material having a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprising an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1.
A two layer fluidized bed in a vessel comprising:
- (a) a fluidizing gas passing upwardly through the vessel;
- (b) a lower fluidized layer in the vessel comprising a first particulate solid having a mean particle size of greater than 200 microns and a bulk density greater than 0.8 g/cm.sup.3 ;
- and
- (c) an upper fluidized layer in the vessel on top of and substantially separate from the lower fluidized layer, the upper fluidized layer comprising tendrillar carbonaceous material having a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprising an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1.
A method for fluidizing a first particulate solid and a second particulate solid, the first particulate solid having a mean particle size greater than 200 microns and a bulk density greater than 0.8 g/cm.sup.3, and the second particulate solid having a means particle size of less than 200 microns, the method comprising the steps of:
- (a) placing the first particulate solid, the second particulate solid, and tendrillar carbonaceous material in a vessel, the tendrillar carbonaceous material having a composition different from the composition of the first particulate solid and the second particulate solid, the tendrillar carbonaceous material having a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprising an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1;
- and
- (b) passing a fluidizing gas up through the vessel with sufficient velocity to fluidize the first particulate solid in a lower layer in the vessel and to fluidize the second particulate solid and the tendrillar carbonaceous material in an upper layer in the vessel, the two layers being substantially separate.
Dependencies are inferred from the claim text.