1)direct-fired vaporizer,明火直热式汽化器2)direct heating over an open flame,明火直接加热3)backfireing in carburetor,汽化器回火4)direct-fired steam-gas generator for thermal recovery,直燃式热采蒸汽气体发生器5)direct steam generation collector,蒸汽直接冷却槽式太阳集热器(DSG)6)direct fired heater,直接火力加热器
