Drum plants, which produce HMA in a continuous manner, generally offer higher production rates than batch plants for comparable cost. Typical production rates for drum plants vary between about 100 tons/hr up to over 900 tons/hr depending upon drum design. Figure 1 shows the basic components of a drum plant and their functions.
A key component of the drum plant is the burner. The most common fuel used in burner is diesel fuel, which results in a bright orange flame as seen in the video below. A natural gas flame would be essentially invisible. Burners like these can reach temperatures in excess of 760°C (1400°F). Typical HMA temperatures out of the drum are on the order of 150 – 160°C (300 – 325°F).