Mobile asphalt plant

Abstract

A mobile asphalt plant for producing asphalt includes a heating unit, a container unit, a plurality of augers, and an injector. The heating unit includes one or more heaters to generate heated gas, a tank to hold heat transfer oil, and one or more first plenum tubes extending from the heaters to within the tank. The first plenum tubes transport the heated gas to the tank to heat the heat transfer oil. The container unit includes a hopper to receive the aggregate material and one or more second plenum tubes extending from the one or more first plenum tubes and extending within the hopper. The second plenum tubes transport the heated gas from the first plenum tubes to heat the aggregate material. The augers are arranged as a series of augers, with a first one of the augers receiving the aggregate material from the hopper. Each of the augers conveys the aggregate material to a next one of the augers. Each of the augers heats the aggregate material using the heat transfer oil from the tank. The injector is connected to one of the augers and injects asphalt oil into the aggregate material to produce asphalt.

1 . A mobile asphalt plant for producing asphalt from aggregate material and asphalt oil, the mobile asphalt plant comprising:
 a heating unit comprising:
 one or more heaters configured to generate heated gas; 
 a tank configured to holding heat transfer oil; and 
 one or more first plenum tubes extending from the heaters to within the tank, the one or more first plenum tubes configured to transport the heated gas to the tank to heat the heat transfer oil; 
   a container unit comprising:
 a hopper configured to receive the aggregate material; and 
 one or more second plenum tubes extending from the one or more first plenum tubes and extending within the hopper, the one or more second plenum tubes configured to transport the heated gas from the one or more first plenum tubes to heat the aggregate material; and 
   a plurality of augers arranged as a series of augers, wherein a first one of the series of augers is configured to receive the aggregate material from the hopper, wherein each of the plurality of augers is configured to convey the aggregate material to a next one of the series of augers, and wherein each of the plurality of augers is configured to heat the aggregate material using the heat transfer oil from the tank; and   an injector connected to one of the plurality of augers and configured to inject the asphalt oil into the aggregate material to produce the asphalt.   
     
     
         2 . The mobile asphalt plant of  claim 1 , further comprising a conveyor belt for transporting the aggregate material between the hopper and the first one of the series of augers. 
     
     
         3 . The mobile asphalt plant of  claim 1 , wherein each of the plurality of augers comprises:
 a rotating shaft;   one or more flights attached to the shaft; and   an auger motor configured to effect rotation of the shaft;   
       wherein the rotation of the shaft effects movement of the aggregate material along the auger. 
     
     
         4 . The mobile asphalt plant of  claim 3 , wherein at least one of the flights comprise one or more vent openings. 
     
     
         5 . The mobile asphalt plant of  claim 3 , wherein each of the plurality of augers further comprises:
 an interior shell substantially enclosing the shaft and the one or more flights, wherein the aggregate material moves within the interior shell; and   an exterior shell substantially enclosing the interior shell;   
       wherein the interior shell and the exterior shell define, at least in part, a cavity through which the heat transfer oil flows, thereby heating the aggregate material within the interior shell. 
     
     
         6 . The mobile asphalt plant of  claim 5 , wherein movement of the aggregate material through each of the plurality of augers is in an opposite direction to movement of the heat transfer oil through each of the plurality of augers. 
     
     
         7 . The mobile asphalt plant of  claim 6 , further comprising first tubing configured to transport heat transfer oil from the tank to a last one of the plurality of augers in the series of augers. 
     
     
         8 . The mobile asphalt plant of  claim 7 , wherein the heat transfer oil moves through each of the plurality of augers in order from the last one of the plurality of augers to the first one of the plurality of augers. 
     
     
         9 . The mobile asphalt plant of  claim 8 , further comprising one or more auger tubing configured to transport heat transfer oil between the plurality of augers. 
     
     
         10 . The mobile asphalt plant of  claim 9 , further comprising second tubing configured to transport heat transfer oil from the first one of the plurality of augers to the tank. 
     
     
         11 . The mobile asphalt plant of  claim 1 , further comprising a load-out conveyor for transporting the asphalt from the plurality of augers off of the mobile asphalt plant. 
     
     
         12 . The mobile asphalt plant of  claim 11 , wherein the load-out conveyor is a drag slat conveyor. 
     
     
         13 . The mobile asphalt plant of  claim 11 , wherein the load-out conveyor is configured to heat the asphalt. 
     
     
         14 . The mobile asphalt plant of  claim 13 , wherein the load-out conveyor receives heat transfer oil from the tank for heating the asphalt. 
     
     
         15 . The mobile asphalt plant of  claim 1 , wherein each of the augers comprise an inlet for receiving the aggregate material and an outlet for expelling the aggregate material. 
     
     
         16 . The mobile asphalt plant of  claim 15 , wherein the inlet and the outlet are located proximate to opposite ends of the auger. 
     
     
         17 . The mobile asphalt plant of  claim 16 , wherein for at least some of the plurality of augers, the auger is angled such that the inlet is lower than the outlet. 
     
     
         18 . The mobile asphalt plant of  claim 1 , wherein the plurality of augers is six augers. 
     
     
         19 . The mobile asphalt plant of  claim 1 , further comprising a bed for supporting the heating unit, the container unit, the plurality of augers, and the injector. 
     
     
         20 . The mobile asphalt plant of  claim 19 , further comprising a plurality of wheels for supporting the bed.