1, The tunnel kiln is expensive than Hoffmann kiln, but it is new and environment protection. And it can be automatic, so you can use less labor.
2, Cause the bricks on the kiln cars can move in the tunnel kiln, but the burning fire points are certain, so it can be easy to be heat preserving. And the drying room and firing room are side by side, so the extra heat in the firing room can be sent to the drying room to dry the bricks by the fan. So that all the heat can be used sufficiently.
3, The coal consumption of fring one brick is a little less by using tunnel kiln than Hoffmann kiln and the time of the fring bricks is a little short than Hoffmann kiln. What's more, the brick quality of the bricks is a little higher firing in the tunnel kiln than Hoffmann kiln.