History of Bricks and Brickmaking
Bricks are almost as ancient as mankind, and are so common that their existence is almost ignored, or never paid attention to. Dating back to almost 7000 BC, bricks are considered to be the oldest construction material. Sun-dried mud bricks were the very first bricks that were used by civilizations in Jericho and Southern Turkey. The sun-dried bricks were also used as a building material by ancient Egyptians, the remains of which are still available at ancient Mohenjo-Daro and Harappa civilizations in Pakistan.
Romans were the first to use kiln-fired bricks which differed from ancient bricks both in shape and size. Stamped with the legion mark, Roman bricks were then used all over the Roman Empire. Next were the Greeks to recognize the importance of bricks in the construction industry. The 12th century saw the reintroduction of bricks to the Northern Germany. This marked the start of the brick Gothic period in which buildings were made from red fired clay bricks. Considering the fact that sculptures and Gothic figures were difficult to be made out of these bricks, special shaped bricks were made to be used for sculptures.
Plaster made its impact during Baroque and Renaissance periods which meant the unpopularity of exposed brickwork. However, brickwork regained its demand in the mid-eighteenth century. Then came the period of modern brickmaking using sophisticated equipment and the level of sophistication kept on increasing with time.
The manufacturing of bricks involves four basic steps:
Either tempering or weathering is used to make the clay soil easier to work within the moulding and the other processes. Tempering is the addition of water and weathering is the disintegration of clay soil in an open atmosphere where repeated moistening and drying makes the clay soil workable for brickmaking procedure. Mixing or crushing is done to make the mixture smooth and homogeneous. Different admixtures are used while mixing to reduce cracking and also to reduce fuel consumption.
Different techniques like Slop moulding or Sand moulding are used to mould the mixture into a particular shape. Since the mixture shrinks while drying, the shrinkage has to be kept in mind while moulding.
Water has to be removed from the mixture before baking to reduce the cracking and also to reduce the fuel consumption during the baking process. The moulded mixtures are dried slowly using different techniques like Tunnel driers or Automated Chamber dryers to yield evenly dried bricks.
High-temperature furnaces are used to fire the dried mixtures. Cars are used to move the bricks through the kilns and after cooling the settling and packaging is done mostly through automated settlers and the final product is achieved.
Brickmaking has evolved from sun-dried bricks to automated brickmaking machines where everything is automated. There are Fly Ash brickmaking machines, CLC brickmaking machines and other automated machines are being used all over the world especially in the developed countries. UK, USA, Germany, China, Japan, India etc. are using state of the art technology for brickmaking. Manual brickmaking has almost been eliminated however, these practices are still being carried out in remote areas of India, Pakistan, Arab countries and a few other under-developed countries as well.