BatchplantSeperatebatches (1.5-4.5tons)Drum:counterflowExhaustgastemperaturelowerthanindrummixplant.Some30Clower(>120Cversus>150 C)Controlling factor withbaghouses is dew pointTemperature of heated aggregate determinesmixtemperature26August31,2025ATUDelft
August 31, 2025 26 Batch plant • Seperate batches (1.5 – 4.5 tons) • Drum: counter flow • Exhaust gas temperature lower than in drum mix plant. Some 30 C lower (>120 C versus >150 C) • Controlling factor with baghouses is dew point • Temperature of heated aggregate determines mix temperature
Batch plantFourteen MajorPartsCold bins9.Hot bins2Cold Feed gate 1o. Weigh box3Cold elevatorll.Mixing unit-orpugmill4.Dryeri2. Mineral filler storage5.I3.Hot asphalt cemenf storageDustcollector614.Asphaif weigh bucketExhaust stackHot elevator8.Screening unitTUDelft
August 31, 2025 27 Batch plant
Screensand hotbinsBalanced surface area of the hot screensScreens may wear and tear (oversize materialenteringfinermaterial)Screen can be plugged/blinded (fine material inthe course bins)Hotbins mustbelargeenoughBetter control overmixcomposition comparedto drum mix28August31,2025TTUDelft
August 31, 2025 28 Screens and hot bins • Balanced surface area of the hot screens • Screens may wear and tear (oversize material entering finer material) • Screen can be plugged/blinded (fine material in the course bins) • Hot bins must be large enough • Better control over mix composition compared to drum mix
Aggregate in batch plant dryingdrumFigure4.17Counter FlowDrver (Courtesv of Astec
August 31, 2025 29 Aggregate in batch plant drying drum
DIFFERENCEBETWEENANYTWOPOINTS12SHOULD NOTEXCEED80°FCORRECTSHOWERING
August 31, 2025 30