The firing process of red brick and blue brick

Want to know the firing process of red bricks and blue bricks? Come on, let's unveil the mystery behind them.

The birth of red brick

Traditional bricks are made by molding clay and calcining it at high temperature. In the process of calcination, two magical chemical changes have taken place in adobe. Organic matter such as humus will combine with oxygen and become carbon dioxide when it meets high temperature, so the black color in sludge gradually disappears. At the same time, the reduced iron salt in the mud is gradually oxidized at high temperature and turned into iron oxide, which is the birth process of our common red brick.

Manufacturing skills of blue bricks

If you want to burn blue bricks, you have to play some tricks. It is necessary to seal the vent hole at the top of the kiln to reduce the air entry when calcining the adobe at high temperature, which can make the temperature in the kiln more conducive to the reduction of the components of the adobe. Thus, the red high-order iron oxide in the green body was successfully reduced to blue-gray low-price iron oxide, and a perfect blue brick was born!