Drying Process in Ceramic Industries

 Generally the term ‘ceramics’ (ceramic products) is utilized for inorganic materials with presumably some organic content, created from non-metallic compounds and made permanent by a firing method. In addition to clay primarily based materials, these days’ ceramics embrace a large number of products with a little fraction of clay or none at all. Ceramics may be glazed or unglazed, porous or glassy. Firing of ceramic bodies induces time-temperature transformation of the constituent minerals, typically into a combination of recent minerals and glassy phases. Characteristic properties of ceramic merchandise embrace high strength, wear resistance, long service life, chemical inertness and non-toxicity, resistance to heat and fire, (usually) electric resistance and generally also a particular porosity.

Two kinds of energy are utilized in the ceramic industry; electrical energy and chemical energy. The electrical energy is employed in 2 completely different ways; energy once utilized in the motor and fan of the machine, and thermal energy once utilized to heat the kilns and furnaces. The chemical energy of fossil fuel is all converted into thermal energy through combustion reaction. Energy utilized in the ceramic trade is predominantly occupied by fossil fuel energy. The drying method within the ceramic trade is that the greatest energy consumer second to the firing method. Drying suggests that loss of moisture from the surface of the substance by evaporation, and therefore the drying speed depends on the temperature and humidity.

Ceramic Manufacturing Process:

• Raw Materials Procurement & Weighing

The raw materials utilized in the manufacture of ceramics vary from relatively impure clay materials well-mined from natural deposits to ultrahigh purity powders ready by chemical synthesis. Naturally occurring raw materials utilized to manufacture ceramics embrace silica, sand, quartz, flint, silicates, and alumino silicates. the primary step within the method is to weigh the raw materials needed to manufacture a ceramic tile all sorts of every type of frit, feldspar and numerous clays. All the raw materials are accurately weighed, in order that the standard of the product may be stabilized.

• Fine Grinding & Milling

The basic beneficiation processes contains crushing, grinding, and sizing or classification. Primary crushing is employed to reduce the dimensions of coarse materials, like clays, down to some one to five centimeters. The foremost common sorts of crushers used are jaw crushers, cone crushers, gyratory crushers, and roll crushers. Secondary crushing or grinding reduces particle size right down to someone millimeter in diameter. Fine grinding or milling reduces the particle size right down to as low as one.0 micrometer in diameter. Ball mills are the foremost usually used piece of equipment for milling. 

• Filter Press

During the method to form clay and ceramic slurries used for the manufacture of dinnerware, insulators, china etc., the clay slurry goes through a dewatering step before any process and molding into the required. These slurries are very dense and heavy and usually need dewatering at 225 PSI feed pressure to get a solid cake.

• Mixing

Mixing ensures a standardized distribution of clay within the solution. It conjointly prevents the sedimentation of clay that is fascinating for the method of ceramic formation. pug Mills are most typically used for combination in ceramic production.

• Spray Drying

Ceramic tiles are usually shaped by dry pressing. Before pressing, several facilities granulate the ceramic mix to create a free-flowing powder, thereby improving handling and compaction. The foremost ordinarily used methodology of granulation is spray-drying. The slurry is injected into a drying chamber with hot gases. Because the hot gases are available in contact with the slurry, a powder is made and picked up during a cyclone or fabric filter. Spray dryers typically are gas fired and operate at temperatures of 70° to 570°C. When spray drying, the water content of the granules is between 35-40%.

• Powder Storage

The granules need to be kept in a storage bin for a couple of days so its composition becomes even a lot of homogeneous. This method makes the granules a lot of pliable and less doubtless to stay to the mould. The size of powder storage bin required is going to be determined by the production capability of the plant. Generally, the foremost appropriate size is capable of holding tons of plenty of powder.

• Shaping

In the forming step, the ceramic mix is consolidated and shaped to provide a cohesive body of the required form and size. Forming strategies may be classified as either dry forming, plastic molding, or wet forming. Once the composition of the powder becomes homogenized, it’s taken to the press wherever it’s shaped and squeezed below high pressure to create a biscuit or Greenware tile body.

• Glazing

Glazes resemble glass structure and texture. The aim of glazing is to supply a smooth, shiny surface that seals the ceramic body. Not all ceramics are glazed. Those who are glazed are often glazed before firing, or may be glazed when firing, followed by re firing to line the glaze.
 
• Speed Body Drying

The drying method within the ceramic industry is that the greatest energy consumer second to the firing method. Drying suggests that loss of moisture from the surface of the substance by evaporation, and therefore the drying speed depends on the temperature and humidity. Once the substance is dried and moisture is lost, particles are placed near, resulting in shrinkage.

• Firing

Firing is that the method by which ceramics are thermally consolidated into a dense, cohesive body composed of fine, uniform grains. This method is also remarked as sintering or densification. Ceramics usually are fired at 50-75% of absolutely the melting temperature of the material. Ceramic product are manufactured by pressure firing, that is comparable to the forming method of dry pressing except that the pressing is conducted at the firing temperature.

• Packing

The finished products are then packed and stored or shipped.

Two types of drying process done in the manufacturing of ceramic tiles:

1. Drying through spray dryer
2. Drying through vertical dryer

To improve the utilization of the energy consuming in drying method. Here in ceramic tiles producing method the drying method is second most energy consuming method after the firing method. For currently regarding the energy consumption we’ve to analysis the method. Thus we have a tendency to visit the one company and analysis the producing method and from the analysis we have a tendency to do the mass balance and energy balance of drying method for the know about the energy consumption.

We at KERONE have a team of experts to help you with your need for drying of ceramic in various products range from our wide experience.