It is also by using pneumatic conveying systems for ceramics that this industry in our geographical area became a world leader in tile production. There are many objectives: production automation, obtaining better finished products in less time, saving money, containing risks and reducing polluting emissions.
The highest presence of companies in the sector is in the provinces of Modena and Reggio Emilia. Production is concentrated primarily on porcelain stoneware, then single-fired tiles and finally double-fired tiles.
Pneumatic transport in ceramics industry can move raw materials, such as ceramic powders, sands and atomized materials, preserving their integrity and temperature and humidity characteristics. This includes alumina, quartz, kaolin, pigments, micronised grindings, oxides and frit. The material flows fluidly through closed pipes, possibly insulated to maintain a constant temperature and at low speed to prevent deterioration. Thanks to the pipelines, it can be stored in silos, delivered to receiving stations, fed to shot blast machines or even dosed and mixed to perfection.
Another function very well performed by pneumatic conveying in ceramic production plant is the cleaning: not only limited to the room and machinery, but also to the products during the production cycle. For example, it is possible to vacuum up excess glaze on tiles or, using centralised systems, remove dust, residues and debris, quickly conveying them all to a single collection point.
The basic element used in the production process of porcelain stoneware is called atomized barbotine. It is initially obtained by grinding and mixing clays, sands, feldspars and add water until obtaining a creamy, fairly viscous mixture, called barbotine.
This is followed by an atomisation phase, where a nebuliser expels the slip into a drying chamber, causing rapid solidification into a powder. In this way the atomised material will have an excellent particle size distribution in terms of flowability, which will ensure more efficient handling than in liquid form. The atomised powder is then brought into storage silos to be used on the production lines.
Conveyor belts and mechanical screw conveyors are generally used to move the atomised powder: these are effective methods, but there are problems with the crumbling of the material. Atomised slips are extremely fragile due to the low water content and the impact and friction between particles and mechanical parts that transport them. The result is a crushing that generates very fine dust containing silicon dioxide, dangerous if inhaled. In addition, the crushed material can no longer be used effectively for tile production. In order to remove this harmful dust, companies install large, expensive extraction systems that, despite their enormous energy consumption, do not always manage to remove all the fine dust.