Abstract: A combustion chamber having improved heating efficiency and reduced NO.sub.x emissions includes a reduced diameter throat and a stepped configuration within the chamber. The chamber configuration encourages efficient combustion to reduce NO.sub.x production by promoting the formation of eddy currents within the chamber. A method for increasing heating efficiency and reducing NO.sub.x production is provided and involves passing combustion gases through such a combustion chamber.

Abstract: A combustion chamber having improved heating efficiency and reduced NO.sub.x emissions includes a reduced diameter throat and a stepped configuration within the chamber. The chamber configuration encourages efficient combustion to reduce NO.sub.x production by promoting the formation of eddy currents within the chamber. A method for increasing heating efficiency and reducing NO.sub.x production is provided and involves passing combustion gases through such a combustion chamber.

Abstract: Closure apparatus for the opening in the top of a storage bin or the like, including means for providing a liquid seal between the inside of the storage bin and the outside atmosphere. The apparatus includes a reservoir surrounding the opening in the storage bin and a movable gate structure including a downwardly extending wall that is lowered into the reservoir when the gate structure is moved into a closed position.

Abstract: Apparatus and method for measuring out liquid asphalt gravimetrically. The apparatus comprises a plurality of tanks for containing liquid asphalt, each tank being suspended from a load cell, a series of pipes, valves and a pump for selectively filling the tanks with asphalt and a series of pipes, a valve and a variable rate pump for selectively removing the liquid asphalt from the tanks. The load cells are connected to a control circuit which converts the signals from the load cells into the corresponding weight of the tanks and the liquid asphalt contained therein. The control circuit is also connected to the variable rate pump to control the rate at which liquid asphalt is removed from the tank in response to the load cells.

Abstract: Drum mix asphalt plant apparatus connected to a fiber filter dust collector for removing dust and other light particulate matter produced by operation of the drum mixer. Asphalt material is added to the drum mixer in a manner to minimize smoking of the asphalt material due to high temperature within the mixer, and the resulting dust and other fine particulate matter evolved from aggregate material within the drum mixer is withdrawn and collected in a fiber filter dust collector system such as a baghouse. The collected dust is returned to the drum mixer to be coated with asphalt material therein, so that the returned dust becomes admixed with the asphalt aggregate contents of the drum mixer.

Abstract: Continuous asphalt plant including a temperature control system for controlling the temperature of the asphalt-aggregate mix by varying the flow of hot gases through a mixing enclosure. The temperature of the source of heat, such as a flame burner, is controlled to maintain the temperature of the hot gases as they enter the mixing enclosure, and the hot gases are recirculated to assist in controlling the temperature of the hot gases entering the mixing enclosure and to provide more efficient operation of the plant.