DRYING AND HEATING OF BITUMINOUS CONCRETE AGGREGATES

A METHOD WAS DEVELOPED, CALLED THE THREE-VALUE METHOD, WHICH CONSISTS OF USING THREE VALUES OF PRINCIPAL VARIABLES (AGGREGATE HEATING RATE, DRYER TEMPERATURE GRADIENT, AND DRYER RESIDENT TIME) TO COMPUTE AGGREGATE DISCHARGE TEMPERATURES AND MOISTURE CONDITIONS. THE REPORT CONTAINS PROCEDURES AND DETAILS FOR MEASURING THE THREE VALUES DESIRED AND INCLUDES A DISCUSSION OF THEIR SIGNIFICANCE. ALSO INCLUDED IS A DETAILED PROCEDURE OF THE METHOD USED TO RELATE THE VALUES IN THE DRYER OPERATION. A PROTOTYPE DRYER WAS TESTED TO VERIFY THE DEVELOPED METHOD. A SECTION CONTAINS PRACTICAL PROBLEMS INVOLVING DRYER VARIABLES WHICH ARE FOUND BY THE THREE VALUE METHOD AND HEAT BALANCE PROCEDURES. OPERATIONAL EFFICIENCY IS ALSO DISCUSSED BASED ON THE RESULTS FOUND BY CHANGING DRYER VARIABLES IN THE METHOD. A METHOD TO REGULATE AND SET A DRYER TO GIVEN EFFICIENT OPERATING CONDITIONS IS GIVEN.

• Corporate Authors:

  Ohio State University, Columbus

  Engineering Experiment Station, 2070 Neil Avenue
  Columbus, OH  United States  43210
• Authors:
  • Lottman, R P
• Publication Date: 1962-6-30

Subject/Index Terms

• TRT Terms: Aggregates; Bituminous aggregates; Concrete aggregates; Driers (Devices); Drying; Drying rate; Economic efficiency; Moisture content; Prototypes; Temperature; Variables; Wetting and drying tests
• Uncontrolled Terms: Efficiency
• Old TRIS Terms: Aggregate drying; Drying temperature; Drying tests; Three value method
• Subject Areas: Bridges and other structures; Economics; Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00217641
• Record Type: Publication
• Source Agency: Highway Research Board
• Report/Paper Numbers: Final Rept
• Files: TRIS
• Created Date: Apr 21 1994 12:00AM