Asphalt preparation plant

Claim 2

In a plant for forming asphalt mix or the like including an aggregate dryer for drying aggregate and a mixer for mixing a bituminous liquid with the aggregate, the combination therewith of air flow means for inducing a flow of air from the aggregate dryer through the mixer, a dust collector positioned in the air flow means for collecting heavy dust particles from the air flow, and spray means for forming a bituminous mist in said mixer in the air flow.

Claim 3

The invention of claim 1 and further including means for combining the heavy dust from the dust collector with the aggregate.

Claim 4

Apparatus for making an asphalt mix comprising a mixing cylinder positioned with its longitudinal axis at an incline and having an upper end and a lower end, means for rotating said mixing cylinder about its longitudinal axis, aggregate feed means positioned at the upper end of said mixing cylinder for feeding aggregate to said mixing cylinder, heating means positioned at the upper end of said mixing cylinder for heating the aggregate fed to said mixing cylinder, an aggregate and air flow constricting means for forming an opening of smaller cross-sectional area than said mixing cylinder positioned intermediate the ends of said mixing cylinder, air flow means arranged to create a flow of air through saId mixing cylinder from the upper end toward and out of the lower end at a velocity sufficient to cause at least some aggregate in said mixing cylinder to become airborne in said flow of air and pass in said flow of air through said opening, bituminous spray means for spraying bituminous liquid into said flow of air in said mixing cylinder at a position down stream from said opening.

Claim 5

Apparatus for making an asphalt mix comprising a mixing cylinder positioned with its longitudinal axis at an incline and having an upper end and a lower end, means for rotating said mixing cylinder about its longitudinal axis, aggregate feed means positioned at the upper end of said mixing cylinder for feeding aggregate to said mixing cylinder, heating means positioned at the upper end of said mixing cylinder for heating the aggregate fed to said mixing cylinder, an aggregate and air flow constricting means for forming an opening of smaller cross-sectional area than said mixing cylinder positioned intermediate the ends of said mixing cylinder, air flow means arranged to create a flow of air through saId mixing cylinder from the upper end toward and out of the lower end at a velocity sufficient to cause at least some aggregate in said mixing cylinder to become airborne in said flow of air and pass in said flow of air through said opening, bituminous spray means for spraying bituminous liquid into said flow of air in said mixing cylinder at a position down stream from said opening.

Claim 6

The apparatus of claim 3 and wherein said aggregate feed means comprises a plurality of aggregate storage bins for storing and dispensing sized aggregates, and conveyor means extending between said aggregate storage bins and the upper end of said mixing cylinder.

Claim 7

The apparatus of claim 3 and wherein said air flow means is positioned at the lower end of said mixing cylinder and arranged to draw air through said mixing cylinder.

Claim 8

The apparatus of claim 3 and wherein said heating means comprises an open flame burner arranged to project a flame toward the lower end of said mixing cylinder.

Claim 9

The apparatus of claim 3 and wherein said bituminous spray means comprises a plurality of nozzle openings positioned within said mixing cylinder and arranged to spray bituminous liquid into said flow of air passing through said opening.

Claim 10

The apparatus of claim 3 and wherein said bituminous spray means comprises a plurality of spray nozzles positioned with in said mixing cylinder and supported from outside said mixing cylinder.

Claim 11

A process of preparing asphalt mix or the like comprising drying a mass of aggregate, flowing air through the aggregate as the aggregate is dried and carrying dust from the aggregate with the air to a separator, separating heavier dust from the flowing air, washing the air and lighter dust with a bituminous liquid, combining the lighter dust and bituminous liquid with the dried aggregate, mixing the combined lighter dust, bituminous liquid and dried aggregate, and adding selected amounts of the heavier dust to the mixture.

Claim 12

A process of preparing asphalt mix or the like comprising drying a mass of aggregate, flowing air through the aggregate as the aggregate is dried and carrying dust from the aggregate with the air to a separator, separating heavier dust from the flowing air, washing the air and lighter dust with a bituminous liquid, combining the lighter dust and bituminous liquid with the dried aggregate, mixing the combined lighter dust, bituminous liquid and dried aggregate, and adding selected amounts of the heavier dust to the mixture.

Claim 13

The process of claim 9 and wherein the step of adding selected amounts of the heavier dust to the mixing chamber comprises applying bituminous liquid to the heavier dust prior to adding the heavier dust to the mixture.

Claim 14

In a process of making asphalt mix wherein aggregate is dried and a bituminous liquid is mixed with the aggregate, the step of combining the dust from the aggregate and the bituminous liquid and mixing the dust-liquid with the aggregate.

Claim 15

In a process of making asphalt mix wherein aggregate is dried and a bituminous liquid is mixed with the aggregate, the step of combining the dust from the aggregate and the bituminous liquid and mixing the dust-liquid with the aggregate.

Claim 16

The process of claim 11 and wherein the step of combining the dust from the aggregate and the bituminous liquid comprises flowing the dust in a stream of air and spraying the bituminous liquid into the dust laden stream of air.

Claim 21

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; fan means for creating a flow of air through and out of said drying means of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; entrapping means for removing at least a portion of said some of said aggregate from said flow of air by entrapping said portion in a bituminous liquid; and mixing means for mixing said bituminous liquid having said Portion entrapped therein with said rest of said aggregate.

Claim 22

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; fan means for creating a flow of air through and out of said drying means of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; entrapping means for removing at least a portion of said some of said aggregate from said flow of air by entrapping said portion in a bituminous liquid; and mixing means for mixing said bituminous liquid having said Portion entrapped therein with said rest of said aggregate.

Claim 23

The plant of claim 15 in which said mixing means mixes a predetermined quantity of said bituminous liquid having said portion entrapped therein with said rest of said aggregate.

Claim 24

The plant of claim 15 in which said entrapping means is a spray means arranged to spray bituminous liquid into said flow of air.

Claim 25

The plant of claim 17 in which said spray means comprises an inverted U-shaped nozzle having nozzle openings directed generally inwardly across the space bounded by said nozzle.

Claim 26

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; air flow means for creating a flow of air through and out of said drying means of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; and entrapping means for removing at least a portion of said some of said aggregate from said flow of air by entrapping said portion in a bituminous liquid.

Claim 27

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; air flow means for creating a flow of air through and out of said drying means of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; and entrapping means for removing at least a portion of said some of said aggregate from said flow of air by entrapping said portion in a bituminous liquid.

Claim 28

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; air flow means for creating a flow of air through and out of said drying means of sufficient velocity to cause dust in said drying means to become airborne and pass from said drying means in said flow of air; and entrapping means for removing at least a portion of said dust from said flow of air by entrapping said dust in a bituminous liquid.

Claim 29

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate; air flow means for creating a flow of air through and out of said drying means of sufficient velocity to cause dust in said drying means to become airborne and pass from said drying means in said flow of air; and entrapping means for removing at least a portion of said dust from said flow of air by entrapping said dust in a bituminous liquid.

Claim 30

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate by a flow of air of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; constricting means for constricting said flow of air to increase the concentration of said some of said aggregate and thereby provide a relatively concentrated aggregate in said flow of air; entrapping means for removing at least a portion of said concentrated aggregate from said flow of air by entrapping said portion in a bituminous liquid; and mixing means for mixing said bituminous liquid having said portion entrapped therein with said rest of said aggregate.

Claim 31

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate by a flow of air of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air; constricting means for constricting said flow of air to increase the concentration of said some of said aggregate and thereby provide a relatively concentrated aggregate in said flow of air; entrapping means for removing at least a portion of said concentrated aggregate from said flow of air by entrapping said portion in a bituminous liquid; and mixing means for mixing said bituminous liquid having said portion entrapped therein with said rest of said aggregate.

Claim 32

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate by a flow of air of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air, said some of said aggregate including light particles and heavy particles heavier than said light particles; first entrapping means for separating at least a portion of said light particles from at least a portion of said heavy particles by removing said portion of said heavy particles from a flow of air; second entrapping means for removing at least a portion of said light particles from a flow of air by entrapping said light particles in a bituminous liquid; and mixing means for mixing said bituminous liquid having light particles entrapped therein with said rest of said aggregate.

Claim 33

In a plant for forming an asphalt mix from aggregate and a bituminous liquid, drying means for drying said aggregate by a flow of air of sufficient velocity to cause some of said aggregate to separate from the rest of said aggregate and become airborne in said flow of air, said some of said aggregate including light particles and heavy particles heavier than said light particles; first entrapping means for separating at least a portion of said light particles from at least a portion of said heavy particles by removing said portion of said heavy particles from a flow of air; second entrapping means for removing at least a portion of said light particles from a flow of air by entrapping said light particles in a bituminous liquid; and mixing means for mixing said bituminous liquid having light particles entrapped therein with said rest of said aggregate.