HEATING AND DRYING OF AGGREGATE

AGGREGATE DRYERS, TOGETHER WITH THEIR ASSOCIATED EQUIPMENT, ARE AN ESSENTIAL PART OF ASPHALT PLANT PERFORMANCE. IN AGGREGATE DRYING, THE PURPOSE IS TO TRANSFER HEAT TO THE AGGREGATE AND THE ASSOCIATED MOISTURE SO THAT THE AGGREGATE TEMPERATURE WILL RISE AND THE MOISTURE EVAPORATE. AN IMPORTANT CURRENT PROBLEM IN AGGREGATE DRYING IS DUST AND ITS CONTRIBUTION TO AIR POLLUTION. THE PRESENT STUDY ANALYZES VARIOUS TYPES OF HEATING THAT HAVE BEEN USED OR PROPOSED FOR AGGREGATE DRYING, VIZ.: DIRECT DRYERS (DECREASING OPERATING COSTS AND INCREASING THE EFFICIENCY OF CONVENTIONAL ROTARY DRYERS, EXCESS AIR, REFRACTORY LINING IN THE COMBUSTION ZONE, FLUIDIZED BED DRYER, SPOUTED BED DRYER, SIMULTANEOUS DRYING AND ASPHALT COATING IN A FLUIDIZED SPOUTED BED DRYER), INDIRECT DRYERS, HEATING AGGREGATE IN THE PRESENCE OF ASPHALT, INFRARED DRYERS, AND MICROWAVE AND DIELECTRIC DRYERS. GENERAL COMMENTS ARE MADE, A COMPARATIVE EVALUATION IS MADE OF THE VARIOUS METHODS, AND CERTAIN CONCLUSIONS AND RECOMMENDATIONS ARE STATED.

  • Corporate Authors:

    National Asphalt Pavement Association (NAPA)

    5100 Forbes Boulevard
    Lanham, Maryland  United States  20706
  • Authors:
    • Dickson, P F
  • Publication Date: 1971-5

Media Info

  • Features: Figures; References;
  • Pagination: 50 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00211796
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 5 1973 12:00AM