PURPOSE: A short tube supporting heat transfer pipes are connected to the riser by means of a flange, the short tubes are equipped with a hood and connected to the inlet and outlet for the heat transfer medium at both ends of the heat transfer pipe, thus permitting the recovery of the heat in the coke oven gas.

CONSTITUTION: A short tube 6 supporting heat transfer pipes 8 vertically down is connected by means of a flange to the top of the existing riser 3 and covered with a hood 7 at the top and then both ends of the heat transfer pipe 6 are connected to the outlet 10 and inlet 9 for the heat medium, thus recovering the heat in the coke oven gas by exchanging the sensitive heat with the heat medium in the heat transfer pipe 8. Even when the heat transfer pipe is damaged or inspected, only the heat-transfer pipe is demounted for repairing and inspection without demounting the whole riser. The heat transfer pipe 8 is preferably annularly hung down along the inner wall of the riser except the inlet of the bent tube 5 at the part higher than the bent tube inlet.