| 主权项 |
1. A process for increasing the softening point of asphalt comprising the following steps:
providing a liquid jet ejector comprising a motive inlet, a motive nozzle, a suction port, a main ejector body, a venturi throat and diffuser, and a discharge connection; conducting a preheated asphalt feed including fresh asphalt and recycled oxidized asphalt, at a temperature from 125° C. to 300° C., as the motive liquid into the motive inlet of the liquid jet ejector; drawing atmospheric air or compressed air into the suction port of the liquid jet ejector; mixing the preheated asphalt within the main ejector body with the air from the suction port of the liquid jet ejector to form an air/asphalt mixture; conducting the air/asphalt mixture to a heated and pressurized oxidizer vessel via a diptube connected to the discharge connection of the liquid jet ejector; ejecting the air/asphalt mixture from an exit port of the diptube positioned below a liquid level in the oxidizer vessel; collecting an off-gas from the overhead of the oxidizer vessel and an oxidized asphalt product stream from the bottoms of the oxidizer vessel, wherein said oxidized asphalt product stream has softening temperature greater than the preheated asphalt feed; and recycling a portion of the oxidized asphalt product stream back to the liquid jet ejector to form the recycled oxidized asphalt. |
