Development of refractory bricks using clay deposit in Ipokia, Ogun state

This study explores the development of refractory bricks from locally sourced clay deposits in Ipokia I and Ipokia II, located in Ipokia Local Government Area, Ogun State, Nigeria. The research addresses the reliance on imported refractory materials by investigating indigenous alternatives capable of performing under high-temperature industrial conditions. Clay samples were collected at a depth of 1.5 meters and subjected to chemical analysis, which revealed high alumina (Al₂O₃) content of 34.50% in Ipokia I and 27.30% in Ipokia II, and silica (SiO₂) contents of 51.30% and 58.75% respectively values that meet the standard requirements for refractory applications. Refractory bricks were produced and evaluated for key physical and mechanical properties. Results showed that Ipokia I bricks had a higher cold crushing strength of 16.8 MPa compared to 12.4 MPa for Ipokia II. Apparent porosity was 24.6% and 28.3% respectively, while bulk densities were 2.20 g/cm³ and 2.08 g/cm³. Linear shrinkage ranged from 6.5% to 7.2%, and thermal shock resistance tests confirmed durability over multiple heating-cooling cycles. The refractoriness values were 1500°C for Ipokia I and 1450°C for Ipokia II bricks, indicating their suitability for furnace lining in medium to high-temperature applications. Limitations include the absence of industrial-scale testing and long-term performance evaluation. However, the study concludes that these local clays are viable alternatives for refractory brick production. It recommends their adoption for mass production to reduce imports, stimulate local economies, and create employment, while encouraging further research on material optimization and thermal fatigue behavior.