Clay degassing, the process of removing trapped air and gases in clay, is crucial for the brick and tile manufacturing industry. Vacuum technology plays an important role in the processing and manufacture of tiles, bricks, and most ceramics. Vacuum pumps from Atlas Copco play an important role that facilitate the evacuation of these air bubbles and volatile gas compounds from the raw clay material.
Over recent decades, the brick and tile industry has invested heavily in product and process innovations. This has transformed traditional manufacturing processes and altered the way brick and roof tile plants operate. The modernization of manufacturing processes has resulted in fully automated plants and heat recovery systems which help in lowering the carbon footprint and advances in product output quality and overall energy efficiency.
Clay degassing vacuum processes for the brick and tile industry
Clay degassing is the most common use of vacuum, drawing out air bubbles or entrapped gas particles which would risk failure in the kiln or during product lifecycle. Raw clay is degassed by vacuum pumps prior to forming. This process removes trapped air pockets which would otherwise result in a poor quality and unstable product. Preventing air inclusions at the pressing and extrusion stage reduces scrap and improves the final yield of shaped items, while precise vacuum produces high quality clay products with good resistance to frost. Vacuum degassing also substantially improves stability, provides strength, and prevents product damage prior to the drying process. Ultimately, quality bricks and tiles rely on quality vacuum supply.
Removing Air and Gas from moist clay
Fresh and recycled clay contains trapped air and gases that can compromise the quality and structural integrity of bricks and tiles. Atlas Copco vacuum pumps are used to lower the pressure in degassing chambers and pull out the air bubbles and gases from the clay, allowing it to become more compact and smoother. This leads to improved quality and uniformity in the resultant clay products. The degassing process also ensures the clay becomes more malleable, making it easier to mold into the final product. This process also minimizes the risk of cracking or damage during drying and firing stages.
Preventing pin-holing and blistering in ceramic products
Pin-holing and blistering are common defects that can occur in ceramic products due to entrapped air and gases. These appear as small holes on the surface of products. Vacuum pumps used for clay degassing processes significantly reduce such imperfections.
Improved batch processing and efficiency
Clay degassing using Atlas Copco vacuum pumps such as the industry 4.0 ready, energy-efficient GHS VSD+ oil-sealed screw vacuum pump allow for degassing large volumes of clay at once, ensuring consistent quality across multiple batches.
The variable speed and the set point control of the GHS VSD+ series offers optimum vacuum levels enable faster degassing cycles, reduced production time and an increase in overall productivity.
One of Atlas Copco’s successes in this demanding industry is Monier – the Luxembourg based leading global manufacturer of pitched roof products.
Monier is a leading global manufacturer of pitched roof products, making roof tiles for almost a century. Monier are also producers of roofing systems, chimneys and energy system solutions. They are headquartered in Luxembourg.
The design of the Atlas Copco GHS VSD+ makes it an ideal solution for the humid and harsh environments involved in brick and tile manufacture.
The oil injected screw element of the GHS VSD+ series feature oversized bearings which support two solid screws delivering vacuum through an axial principle of compression. This eliminates the mechanical wear traditionally associated with vane technology. The variable speed features of the pump additionally help avoid high power and oil consumption.
The vacuum pump automatically cleans and purges itself, which means maintenance is reduced, even in harsh and humid work environments involved in brick and tile manufacture.
Superior performance
in humid applications for brick and tile manufacturing. Clay degassing is traditionally a challenging application for vacuum machinery because of the risks posed by vapor and dust being drawn into the pump.
This could potentially cause wear to the internal components and degrade the oil lubrication system.
Ideal for high vapor loads
The Atlas Copco GHS VSD+ oil-sealed screw vacuum pump is supplied for clay degassing processes in a humid version – specifically configured for applications with high water vapor loads. The on-board control systems monitor the oil circulation system and regulate conditions to avoid condensation, thus extending the lifetime of its high-performance synthetic oil.
Vapor Control Algorithm
for humid applications. Often steam is used to heat and soften the clay, which substantially changes the degassing properties. Atlas Copco’s Vapor Control Algorithm reacts to changes in the degassing chamber and controls the GHS VSD+ to precisely pull air out of the clay without vaporizing water – which means optimum degassing without drying the product.
Read how the GHS VSD+ vacuum pump helped saved Ibstock Brick, UK’s largest manufacturer of clay and concrete building products, 60% in energy costs.
Ibstock Brick is the UK’s largest manufacturer of clay and concrete building products, employing over 2600 people in the UK and USA with annual sales of almost £430m. Ibstock plc is now one of the biggest building materials businesses quoted on the London Stock Exchange.