Abstract: Heat exchange apparatus is provided for use in a rotary kiln having a bed therein for introducing thermal energy directly into central portions of the bed without lifting or tumbling thereof. In this manner, efficient heat transfer is effected from hot upper portions of the kiln to within central portions of the bed without causing significant dust generation which results in unwanted loss of heat and raw materials from the kiln. A plurality of tubular refractory members are held in a spaced apart relationship with the rotary kiln wall which are heated in the upper portions of the kiln and cooled as they pass through the bed when the kiln is rotated.