The tunnel kiln is an intermittent firing kiln, resembling the structure of a matchbox. The kiln car is pushed into the kiln for firing, then pulled out in the opposite direction after firing to unload the finished ceramics. As the kiln car resembles a shuttle, it is named a tunnel kiln. The tunnel kiln is a thermal equipment for intermittent production with a kiln car as the bottom, featuring reverse (or semi-reverse) flame. It is also known as a drawer kiln due to the kiln car entering and exiting from one end of the kiln. It is one of the kiln types that have rapidly developed in China over the past decade. Besides the high operational flexibility and the ability to produce a variety of products, the tunnel kiln allows the loading, unloading, and partial cooling of the products to be done outside the kiln, which improves working conditions and shortens the kiln's turnaround time. However, due to intermittent firing, the kiln has significant heat retention and heat dissipation losses, with high flue gas temperatures and high energy consumption. The new energy-saving type of tunnel kiln improves the kiln structure and adds waste gas heat recovery devices, greatly enhancing this drawback.