초록 ▼

An apparatus for drying two materials comprising two coaxial cylinders, means for rotating the coaxial cylinders, means for introducing a first material into one end of the inner cylinder, means for heating the first material, means for moving the first material in response to the rotation of the cy

An apparatus for drying two materials comprising two coaxial cylinders, means for rotating the coaxial cylinders, means for introducing a first material into one end of the inner cylinder, means for heating the first material, means for moving the first material in response to the rotation of the cylinders along the interior of the inner cylinder so same is discharged from a second end thereof into an adjacent end of the outer cylinder, means for introducing a second material into the said adjacent end of the outer cylinder, and means for moving the first and second materials in response to the rotation of the cylinders along the interior of the outer cylinder in a direction contra to that of the movement of the first material in the inner cylinder so said first and second materials are discharged from the other end of the outer cylinder. The first material is dried in the inner cylinder by direct heating. The second material is dried in the outer cylinder by the heat exchange between the inner and outer cylinders and the first and second materials thereby conserving energy.

대표청구항 ▼

A method for forming a dry aggregate mixture comprising the steps of: moving a stream of a moist fine aggregate through an inner cylinder of two coaxial cylinders, the inner cylinder being within an outer of the cylinders; heating said fine aggregate by means of heat from a heat source adjacent the

A method for forming a dry aggregate mixture comprising the steps of: moving a stream of a moist fine aggregate through an inner cylinder of two coaxial cylinders, the inner cylinder being within an outer of the cylinders; heating said fine aggregate by means of heat from a heat source adjacent the end of the inner cylinder into which fine aggregate is introduced to a temperature sufficient to dry said fine aggregate; mixing the stream of said dry fine aggregate with a stream of a moist coarse aggregate in the outer cylinder of said coaxial cylinders; moving said mixed stream of said fine aggregate and said coarse aggregate through said outer cylinder of said coaxial cylinders in a direction opposite to the flow of said fine aggregate in said inner cylinder and moving a gaseous atmosphere through said outer cylinder in a direction opposite the flow of said mixed stream through said outer cylinder whereby said coarse aggregate is dried by the heat exchange between said inner and outer cylinders and between said fine aggregate and said coarse aggregate and the gaseous atmosphere in said outer cylinder, while the temperature of said fine aggregate is lowered substantially.