FIELD: Asphalt-concrete production technology. SUBSTANCE: inclined counterflow rotary drum-type mixer has burner head-piece which is located in intermediate position between inlet hole for filler at one end of drum and outlet hole for asphalt-concrete at opposite end of drum. Fan delivers additional air to burner through tube intended for gas-carrying air with hole which communicates with mixing chamber located between burner head-piece and discharge end of drum. Gas-carrying air tube is needed for withdrawing gases from mixing chamber with purpose of their normal flowing through burner flame. Positive withdrawing of gases creates negative pressure in mixing chamber which generates reverse flow of part of gaseous combustion products from drying chamber to mixing chamber for preliminary heating of secondarily utilized asphalt-containing material which enters mixing chamber. Secondarily utilized asphalt-containing material is preliminarily heated due to location of preliminary-heating chamber close to flame zone without direct contact with flame. Hot and dried filler not used earlier is mixed with secondarily utilized asphalt-containing material in preliminary-heating chamber. Also provided are valves to prevent escape of gases emitted from secondarily utilized asphalt-containing material into drying chamber. Application of aforesaid mixer and method ensures high efficiency of process with reduced creation of polluting substances. EFFECT: higher efficiency. 20 cl, 10 dwg
Authors
Dates
1999-10-20—Published
1994-12-13—Filed