Comparison of the Quality of Red Bricks Made with Kaolin and Bauxite Tailings Sartika, Syarifah Aqla
Politeknik Negeri ketapang
Abstract
West Borneo Province has the largest kaolin resources in Indonesia, with around 359 million tons spread across several regencies, including Ketapang Regency. Similarly, the largest bauxite resources in Indonesia are also found in West Borneo Province, with approximately 655 million tons concentrated in Ketapang Regency. Bauxite processing involves washing, which produces a residue in the form of fine mud or clay, known as bauxite tailings. As the volume of tailings from bauxite beneficiation increases, there has been growing attention towards their management. Kaolin is a natural mining material that is white, brittle, non-plastic, and categorized as a type of clay. Clay is commonly used as a raw material in the production of red bricks, roof tiles, and ceramics. The abundance of these resources in Ketapang Regency led to research comparing the quality of red bricks made with kaolin and bauxite tailings. The red bricks were assessed based on the quality standards outlined in SNI 15-2094-2000, with a focus on compressive strength tests. Based on the compressive strength tests, red bricks made with bauxite tailings at compositions of 0%, 20%, and 40% achieved compressive strength values of 3.569 MPa, 4.397 MPa, and 5.610 MPa, respectively. In contrast, kaolin-based red bricks with kaolin compositions of 0%, 20%, and 40% achieved compressive strength values of 3.569 MPa, 4.570 MPa, and 5.728 MPa, respectively. Both the 40% tailings and 40% kaolin compositions meet the SNI standard for compressive strength, which requires a minimum value of 5 MPa. This indicates that the compressive strength characteristics of red bricks made from bauxite tailings and kaolin are similar. Additionally, increasing the proportion of kaolin or tailings in red bricks enhances their compressive strength. Therefore, it can be concluded that bauxite tailings can be effectively used as a mixture in red brick production with a composition of 40%.
