Sand-lime Brick Plant
Raw material preparation
Sand and lime is the main raw material of sand-lime brick production. The sand can be used like river sand, sea sand, Aeolian sand, deposition sand and Concentrator tail minerals and so on while they must be in accordance with some technique data and characteristics and each type adopts different method of mining. Lime production mainly takes the method of calcinations.
Mixture preparation
When mixture preparation starts, mixture design must be carried out at first. Mix design should consider making brick and have sufficient strength to meet pre-established product performance, such as strength, durability, antifreeze and stability in the medium erosion, etc. Strength is not “the higher, the better”, or the product strength, because with the higher intensity, the lime needs to use the better graded sand more, which means raising the cost. Therefore, the mix design is actually to find the most optimal critical point in both technology and economy. During mix design, it is necessary to consider the original conditions: raw materials properties (the mineral and sand particle composition, the chemical composition of lime, the lime content of calcium oxide, hydration speed and temperature, etc.), the products’ quality requirements and suppression, and conservation conditions.
Mixture preparation contains lime digestion, the stirring of measurement mixture, the mixture digestion, and the process of mixture digestion and treatment.
Brick Molding
Once mixed and a properly adjusted about moisture content, the sand and lime mix is conveyed to feed the brick presses. Normally the presses are of the rotary table with an output of up to 3000 bricks per hour. As each brick is produced, they are normally stacked automatically and wait to be transferred to the hardening chambers known as Autoclaved.
Essentially the autoclave is a large pressure cooker into which the uncured bricks are conveyed on trucks running on rails. Once the bricks are placed within the autoclave, the chamber is sealed. Steam is introduced and the pressure is steadily increased for about an hour and then maintained at pressures of 8 to 16 bars and the temperature is raised up to approximately 200 °C. After several hours, the steam is then shut off and the steam in the autoclave is released through a valve, which allows the bricks to cool down steadily. At this point the bricks are cured and have developed their final properties, especially the strength, and then they are ready for removal from the autoclave and on to packing and dispatch.Capacity:150 to 2000 m³/day
Raw materials:Sand lime,Fly Ash,Cement
Autoclaved sand-lime brick production process consists of raw materials preparation, mixture preparation, brick molding, autoclave conservation and several major processes.