Dryer for aggregate and reclaimed asphalt products
AssigneeAsphalt Drum Mixers, Inc.
InventorRobert J. Hatfield
Life of this patent
Estimating the term…
Abstract
A dryer for use in an asphalt plant for heating and drying virgin aggregate and also pre-heating reclaimed asphalt products (RAP). A drying drum cylinder having a burner at one end heats and dries virgin aggregate traveling therethrough. A second cylinder near the burner surrounds the drying drum and creates an annular cavity. RAP is introduced and travels through the annular cavity and exits adjacent the drying drum aggregate exit opening. Heat given off by the drying drum increases the temperature within the annular cavity and heats the RAP traveling therethrough. Heated aggregate and RAP first come in contact with one another after exiting the annular cavity and the drying drum and are, thereafter, delivered to a mixing drum.
Claims25
A dryer for heating and drying aggregate and heating reclaimed asphalt products, said dryer comprising:
- a first cylindrical drum adapted for rotating about its longitudinal axis and having a first opening at one longitudinal end and a second opening at its other longitudinal end, said aggregate being introduced through said first opening, travels through said drum, and exits through said second opening;
- a heat source providing heated gases into said drum through said second opening and heating said aggregate as it travels through said drum;
- a second cylinder being coaxial with and, at least in part, surrounding said first cylindrical drum and forming an annular cavity between said first cylindrical drum and said second cylinder, said second cylinder adapted for rotating about its longitudinal axis;
- said annular cavity having an inlet and having an outlet adjacent said first drum second opening;
- and, a back shroud at said first drum second end enclosing said first drum second opening and said annular cavity outlet and having a shroud outlet;
- and,
- wherein reclaimed asphalt products are introduced into said annular cavity through said inlet, travel through said annular cavity whereat they are heated without contacting said heated gases, and exit said annular cavity through said outlet adjacent heated aggregate exiting said first drum second opening, whereby said heated aggregate and reclaimed asphalt first come in contact with one another in said shroud and thereafter exit said back shroud through said shroud outlet.
Dependencies are inferred from the claim text.