Apparatus for mixing and homogenising bulk material and method of operating the apparatus

Claim 2

Apparatus suitable for pneumatically mixing materials in finely divided form comprising: a. a vertically extending container having an inlet opening adjacent its upper end for introduction of finely divided materials, and an outlet means in the lower end outfitted with means for selectively closing the outlet, for withdrawal of mixed materials, b. a vertically extending riser disposed in the container above and spaced from the outlet opening and comprising an upper section and a lower section, said sections being in overlapping, radially spaced relation defining an annular pasSage therebetween, with the upper section terminating above the lower section and the lower section having its lower end at least as low as the lower end of the upper section, c. means for supplying gas for said mixing to the container below the lower end of the riser for passage of gas into the container and pneumatic lifting and mixing of the gas and materials in the riser with the materials filling the container to above the lower end of the riser.

Claim 3

Apparatus according to claim 1, the lower end of the riser lower section diverging upwardly.

Claim 4

Apparatus according to claim 1, and means for adjusting the flow area of the annular passageway of the riser.

Claim 5

Apparatus according to claim 1, and means for selectively closing the annular passageway of the riser.

Claim 6

Apparatus according to claim 1, said means for supplying gas for said mixing comprising two vertically spaced gas inlet conduits and valve means for selectively apportioning the flow of gas between the two conduits.

Claim 7

Apparatus according to claim 1, the lower end of the lower section of the riser terminating below the lower end of the uppersection of the riser.

Claim 8

Apparatus according to claim 1, and a baffle disposed above and spaced from the upper end of the riser for intercepting the mixture of gas and particles and separating the particles from the gas.

Claim 9

Apparatus according to claim 7, and a gas outlet above the baffle for discharge of the gas from the container after said separation by the baffle.

Claim 10

Process of pneumatically mixing materials in finely divided form with apparatus comprising: a. a vertically extending container having an inlet opening adjacent its upper end for introduction of finely divided materials, and an outlet means in the lower end outfitted with means for selec-tively closing the outlet, for withdrawal of mixed materials, b. a vertically extending riser disposed in the container above and spaced from the outlet opening and comprising an upper section and a lower section, said sections being in overlapping, radially spaced relation defining an annular passage therebetween, with the upper section terminating above the lower section and the lower section having its lower end at least as low as the lower end of the upper section, c. means for supplying gas for said mixing to the container below the lower end of the riser for passage of gas into the container and pneumatic lifting and mixing of the gas and materials in the riser with the materials filling the container to above the lower end of the riser, said process comprising: d. filling the container with finely divided material to a level between the upper end of the riser lower section and the upper end of the riser upper section, e. supplying gas via said gas supplying means for passage therof into the container and pneumatic lifting and mixing of the gas and finely divided materials in the riser, f. said level of the finely divided material being such that finely divided material during the process flows downwardly through said annular passageway and into the mixture of gas and finely divided material rising through the riser, and g. maintaining the finely divided material at said level during the process.

Claim 11

Process of pneumatically mixing materials in finely divided form with apparatus comprising: a. a vertically extending container having an inlet opening adjacent its upper end for introduction of finely divided materials, and an outlet means in the lower end outfitted with means for selec-tively closing the outlet, for withdrawal of mixed materials, b. a vertically extending riser disposed in the container above and spaced from the outlet opening and comprising an upper section and a lower section, said sections being in overlapping, radially spaced relation defining an annular passage therebetween, with the upper section terminating above the lower section and the lower section having its lower end at least as low as the lower end of the upper section, c. means for supplying gas for said mixing to the container below the lower end of the riser for passage of gas into the container and pneumatic lifting and mixing of the gas and materials in the riser with the materials filling the container to above the lower end of the riser, said process comprising: d. filling the container with finely divided material to a level between the upper end of the riser lower section and the upper end of the riser upper section, e. supplying gas via said gas supplying means for passage therof into the container and pneumatic lifting and mixing of the gas and finely divided materials in the riser, f. said level of the finely divided material being such that finely divided material during the process flows downwardly through said annular passageway and into the mixture of gas and finely divided material rising through the riser, and g. maintaining the finely divided material at said level during the process.

Claim 12

Process of mixing materials in finely divided form with apparatus comprising: a. a vertically extending container having an inlet opening adjacent its upper end for introduction of finely divided materials, and an outlet means in the lower end outfitted with means for selectively closing the outlet, for withdrawal of mixed materials, b. a vertically extending riser disposed in the container above and spaced from the outlet opening and comprising an upper section and a lower section, said sections being in overlapping, radially spaced relation defining an annular passage therebetween, with the upper section terminating above the lower section and the lower section having its lower end at least as low as the lower end of the upper sectIon, c. means for supplying gas for said mixing to the container below the lower end of the riser for passage of gas into the container and pneumatic lifting and mixing of the gas and materials in the riser with the materials filling the container to above the lower end of the riser, said process comprising: d. filling the container with finely divided material to a level between the upper and lower ends of the riser lower section, e. supplying gas via said gas supplying means for passage thereof into the container and pneumatic lifting and mixing of the gas and finely divided materials in the riser, f. part of the mixture of gas and finely divided material passing through the riser leaving the riser pipe via said annular passage, while periodically another portion of the finely divided materials rises into the upper section of the riser which portion, after reaching a certain height, collapses to form a plug of material and is mixed together with the material transported from the bottom of the container through the lower section of the riser and discharges through the annular passage.

Claim 13

Process of mixing materials in finely divided form with apparatus comprising: a. a vertically extending container having an inlet opening adjacent its upper end for introduction of finely divided materials, and an outlet means in the lower end outfitted with means for selectively closing the outlet, for withdrawal of mixed materials, b. a vertically extending riser disposed in the container above and spaced from the outlet opening and comprising an upper section and a lower section, said sections being in overlapping, radially spaced relation defining an annular passage therebetween, with the upper section terminating above the lower section and the lower section having its lower end at least as low as the lower end of the upper sectIon, c. means for supplying gas for said mixing to the container below the lower end of the riser for passage of gas into the container and pneumatic lifting and mixing of the gas and materials in the riser with the materials filling the container to above the lower end of the riser, said process comprising: d. filling the container with finely divided material to a level between the upper and lower ends of the riser lower section, e. supplying gas via said gas supplying means for passage thereof into the container and pneumatic lifting and mixing of the gas and finely divided materials in the riser, f. part of the mixture of gas and finely divided material passing through the riser leaving the riser pipe via said annular passage, while periodically another portion of the finely divided materials rises into the upper section of the riser which portion, after reaching a certain height, collapses to form a plug of material and is mixed together with the material transported from the bottom of the container through the lower section of the riser and discharges through the annular passage.