The utilization of various waste materials from the ceramic industry is a widely used practice. Mineral waste is primarily used as an alternative source of SiO2, Al2O3, and/or Fe2O3. Water treatment processes generate sludge that is disposed of in landfills and can have a long-term environmental impact. This project aims to evaluate and enable the reuse of these industrial waste materials in the production of traditional ceramic materials. It will be studied how the waste can affect the performance of ceramic elements from a technical point of view (mechanical strength, dimensional homogeneity, aesthetics, and durability in laboratory-scale specimens), as well as production parameters (extrudability and process efficiency). Therefore, the integration between the effects on the final product and the impact on production processes enhances the real inclusion and utilization of these waste materials in the ceramic industry.

There is a wide variety of waste materials that can be reused by the ceramic industry; however, the application of beneficiation treatments (in addition to transportation-related costs) can make their actual inclusion in production processes economically unfeasible. Considering the high heterogeneity in the types of waste, composition, and physical characteristics, their proportion as raw material varies significantly and will depend on the impact on technical aspects (production performance and effect on the properties of the final product), as well as environmental aspects (gas emissions during firing and leaching of heavy metals in the ceramic matrix). It should be noted that the advancement in the use of these waste materials in the production of bricks/tiles from a commercial and technical point of view is limited to how the presence of alternative raw materials (or partial substitution of clays/fuels) affects the final properties of the product obtained. However, their effect on production parameters, such as changes in the plasticity and consistency of the clay mass during molding, has not yet been studied in much detail. Even though bricks and tiles of different sizes and geometries available on the market are mainly molded using an extrusion process, there are few studies evaluating the effect of waste on ceramic products obtained through this process. The performance and effectiveness of the extrusion process depend on the rheological properties of the clay mass, as well as the configuration of the extruder. Particle size distribution, moisture content, type/mineralogy, and properties of the clay mixture are the most important parameters.

In this way, this project will integrate a complete evaluation of technical, environmental, and economic aspects with the objective of maximizing the real application and utilization of waste in red ceramics. At the technical level, the local availability of waste (at least two types), the effect on the rheological properties of the clay plastic mass during molding, shrinkage during drying and calcination, as well as the final properties of the product (mechanical resistance, porosity, absorption, density, dimensional uniformity, aesthetic appearance, among others) will be considered.

This project will integrate the participation of different graduate (master's) and undergraduate (scientific and technological initiation scholarship holders) students, as well as the strengthening of the proponent's strategic partnerships with other national and international research institutes.