Use of zeolite rocks for ceramic bricks based on brick clays and clay loams with high drying sensitivity

• Published in: Construction & building materials Vol. 255; p. 119324
• Main Authors: Vakalova, T.V., Revva, I.B.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.09.2020
• Subjects: Ceramic brick; Clay; Drying sensitivity; Sintering ability; Zeolite; Clay; Zeolite; Drying sensitivity; Sintering ability; Ceramic brick
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2020.119324

•Using natural raw materials with structural porosity of the rock-forming mineral (zeolite rocks) to obtain ceramic bricks was investigated.•Effectiveness of zeolite additive depending on their dispersion, content and temperature conditions was established.•The addition of zeolite rock (10–30 wt.%) to brick clay acts as a moisture extractor, reducing the index drying sensitivity by 3–4 times without impairing the materials cohesiveness. The possibility of using natural raw materials with the structural porosity of the rock-forming mineral (zeolite rocks) to obtain ceramic bricks was investigated. It was determined that the effectiveness of zeolite additives is determined by their dispersion, content in the mass, type of clay raw materials, as well as the temperature conditions of processing of ceramic materials. The addition of zeolite rock in the amount of 10–30% to mixtures with highly drying-sensitive clay or clay with high natural humidity acts as a moisture extractor and non-plastic additive. This additives reduces the index of drying sensitivity by a factor of 3.5–4 without impairing the material cohesiveness. It has favourable effects on the crack resistance of green products during drying and enables automated, reject-free loading of the dry products into a kiln. The improvement of the drying properties of clay raw materials is achieved by transferring part of the free water introduced from the flooded clay into a bound state by entering it into the channel-frame space of zeolite minerals. The established effect of zeolite rocks allowed to develop a method for controlling the moulding and drying properties of clays with high natural humidity and (or) with high sensitivity to drying, as well as process flow sheet for ceramic bricks from clay-zeolite compositions by the plastic method.