The Fans Used in the Ceramic and Brick Industry
Bricks have always been, and continue to be, of the most popular materials used in the building and construction of structures, spaces, rooms, and foundations. They’re regarded as a robust construction material as these blocks are able to retain heat, withstand corrosion, and resist very high temperatures, compared to other materials. With minimal maintenance and upkeep needed, they can even last a long time – centuries even.
Another product that can be discussed when speaking of the same industry are ceramics, which are generally manufactured from inorganic compounds. Ceramics and bricks become synonymous at one point because they basically start off the same, in terms of material and manufacturing process. However, the end result is what differs.
The sourcing of their raw materials usually begins with procuring clay, which is crushed, mixed with other compounds and water, molded and pressed into the shapes they’re intended for. However, to produce the hardened state of bricks or ceramics, these materials have to pass through several steps, with each one as critical as the next.
What To Remember When Making Bricks and Ceramics
Because of how raw clay compounds react to water and moisture, being able to draw them out completely, without doing it too quickly, is the balance that has to be achieved to produce the best quality of brick and ceramic products. The slightest change in any of these factors will result in a variation of the final output.
If ceramics or bricks come into contact with any form of moisture during the drying process, when it moves to the firing process and heating is done too quickly, water will evaporate at a fast rate from the clay. The tendency is that clay will steam inside the body and create a crackle on the surface, ultimately degrading the structural integrity of the brick or ceramic.
In the manufacturing of bricks or ceramics, the process has not evolved completely since its primitive beginnings, but with industrial advancement, companies now know how to scale production efficiently, with volumes much larger and with speed much quicker. This advancement, of course, requires the proper machineries that can help support that.
In particular, industrial fans lend a great help in ensuring that while production capacity increases, outputs will always remain the highest quality. Understanding how the selection process for industrial fans works, it becomes just as ensuring that the entire production chain meets its requirements.
How Bricks Are Made With The Help of Industrial Fans
Let’s breakdown the process of manufacturing bricks as an example, and see what parts these industrial fans play in its production:
1. Preparation of the Clay
This process – after the procurement of raw materials – starts off by making sure that the right consistency and homogeneity is achieved before the clay is processed any further. This step includes vital tasks, from inspecting and cleaning, to weathering it to impart strength, until it is blended with other compounds such as sand to increase its quality.
Sourcing the purest of clay forms is just as important as the processing of those raw materials. These inorganic materials will also create variations in the final output. For example, depending on the amount of iron or lime in the soil, ceramics will usually come out a little darker – if bricks or ceramics come out a little pink, these are known to have a higher iron content; meanwhile, production outputs that come out a little more yellow or white in tint, are known to have higher lime content.
During the molding process, this is where a percentage of water is added to produce a cohesive mass of clay that can be molded more easily. Depending on the process used, the bricks’ end results can range from dry (making use of the clay’s natural moisture) to soft-mud (which contains about 20 to 30 percent more water).
Why is clay dried before it is fired? Drying of brick and ceramic products allows for the clay to set into the mold or shape. This is done before the actual burning process, which allows enough for shrinking to happen to dispel more moisture.
If moisture is not dispelled, the high temperatures in the kiln will cause the water to evaporate more quickly and result in a cracked product. Once dried properly, they now assume a little more strength to be handled, stacked, and led through to the firing process.
In the old process, clay turns into these products by being dried out in the sun for days; however, new technologies and modern machines have come up with artificial drying processes to produce better and more consistent results.
Examples of these are:
- Automatic Chamber Dryer
This is dryer cart loaded with molded brick or ceramic products, which are passed through a chamber where the drying quality is regulated or controlled.
- Tunnel Dryer
This type of industrial fan helps to prevent the risk of condensation by using higher airflow rates.
4. Burning or Firing
Kilns are what you call the furnaces used for firing these clay products. Kilns allow these to turn into bricks and ceramics, because they are insulated pits that have a heating element which allows moisture to be extracted for the clay to eventually harden.
There are two types of kilns: continuous or periodic, where continuous kilns never cool down and operate round the clock until completed batches passing through tunnels in carts are reloaded.
If it hasn’t been so evident in the various steps, industrial fans are the key components in this type of production line; where airflow and the ability to manage that become the most crucial part of the process.
Let’s now get into the ways we see these industrial fans fit particularly in the production process.
Application of Industrial Fans in the Industry of Ceramics and Bricks
Fan selection is done based on its particular impact to the brick/ceramic making process. While industrial fans are applied in various parts of the process, here are a few notable applications.
Kiln Drying Fans
Industrial fans and blowers allow for an even distribution of airflow that allows the clay to compact properly and brings the shrinking down to a minimum. Since these materials are very responsive to the quality of air in the atmosphere, these fans help ensure that the airflow quality and temperature are consistently maintained all throughout the drying process.
Oven Air Recirculation Fans
Industrial fans allow the distribution of air inside the kilns. For example, in a continuous kiln or tunnel, the high temperature of air is fed through one end of the tunnel (the discharge), while industrial fans are used to induce the flow towards the entryway.
Bricks produced varyas they respond greatly to the atmosphere during the firing process. The aim here is to reduce the variations and this is where these industrial fans lend a great help. High pressure industrial fans or blowers are most suitable for this process.
Combustion Air Blowers
Industrial fans and blowers supply combustion air to the kilns and are able to pull air from the atmosphere and force the draft towards the heat source to maintain continuous heating. With this, forced draft fans allow the induction of oxygen and where the key requirement is a stable airflow and constant pressure, provide just that. Controlling this variable allows maximum combustion to be attained.
Centrifugal fan types or backward inclined fans or blowers are most commonly used for this process. Beyond the type of fan, fan selection must consider that the type of fan to be chosen should be able to withstand corrosion and the high temperatures as the process of temperatures in a kiln can reach between 800 and 2000 ºC.
Kilns are often powered by fuel and during the burning process will release potentially-toxic fumes into the atmosphere. Integrating exhaust fans in the ventilation system will ensure a safer and healthier workplace for all the workers involved, as well as increase productivity by encouraging a comfortable and cool working environment.
Centrifugal fans are most applicable here, given the design and its ability to redirect airflow (in or out).
Cooling Bed Fans
Fans are also used during the cooling process. The cooling process involves the batches of items that have been heated but have to be put back to normal temperature so that they can be packaged and sent out efficiently and immediately.
This cooling process is also the last step in the production process, but equally as essential. It is during this process that the now-formed ceramics and bricks come back to temperature and doing so gradually ensures that the ceramic structure is preserved. This process too has an impact on the final color of the ceramic product.
Axial fans are able to distribute airflow across a much larger space with controlled pressure and evenness, allowing them to be suitable for this process.
Fan Selection Process
Clay, compared to metals, softens more slowly and although more malleable, the ability to reproduce with little to no variation is very difficult. With the improvements made to the manufacturing process, ensuring that all aspects of the process run to supplement and improve overall input is the goal.
With this, we wanted to highlight the processes that are able to operate seamlessly by integrating industrial fans into the production flow and what benefits they offer. With fan selection, it is pertinent to study the process first and foremost, to understand the requirements. Once identified, product matching follows. But once the fan systems are installed, it will be fine-tuned based on the location/atmosphere/air density as these all play a part in delivering the optimal performance of an industrial fan.