Production of lightweight firebricks by adding porcelainite to white kaolin and bauxite

Lightweight firebricks are critical in many sectors. There is a growing need to develop materials for furnaces, chambers, and burning towers in various construction and non-construction industries. Iraq offers raw materials that can replace imports. This study aimed to manufacture lightweight firebricks by adding porcelanite in different proportions to white kaolin and bauxite. Four raw-material mixtures were prepared with 9 samples were formed from each mixture (36 total) for evaluation. The study was prepared by performing chemical analysis and Atterberg limits, followed by forming firebrick specimens using the semi-dry pressing method. After drying at 105–110 °C, firing was carried out at 1200, 1300, and 1400 °C with a maturation (soak) time of one hour. The fired specimens were then inspected and tested to determine physical, mechanical, and thermal properties. Physical tests included post-firing longitudinal shrinkage, porosity, and total density; mechanical testing measured compressive strength; and thermal conductivity was assessed for the produced bricks. The results met international and Iraqi standard specifications for lightweight refractories.