PURPOSE: To obtain an apparatus by which tar and asphalt are mixed in a given mixing ratio without being heated to high temperatures and a useful fuel mixture for blasting into blast furnace is obtained continuously.

CONSTITUTION: An asphalt 4 and a tar 9 kept at a constant temperature by a heater 47 are charged into a melting mixer tank 1, where the mixture formed is sent from an overflow port 2 into a sedimentation tank 10 to separate it into a supernatant liquid and unmolten asphalt precipitate. The supernatant liquid is sent through the first mixture component detection circuit 16 to a collector tank 17, and also the precipitate is again sent to the mixer tank 1. The supernatant liquid is then sent through the second mixture component detection circuit 18 to a mixing tank 19 where it is mixed with the tar 9 to form a mixture of an objective mixing ratio, and then the mixture is desulfurized in a tank 13 to obtain a fuel. Each of the detection circuits is provided with flow meters 22 and 32, thermometers 23, 33, and 37, densitometers 24, 34, and 38, viscometers 25, 35, and 39, and level gage 30, and on the basis of the values measured by these, valves 5, 15, and 21, a pump 42, and charge to asphalt 4 are controlled to regulate mixing ratio and flow rate.