Eco-friendly belite cement from crude calcareous oil shale with low calorific value

Many countries have resources of calcareous oil shale with low calorific value that are unsuitable for energy production. The chemical composition of calcareous oil shale is similar to that of Portland cement clinker. This study aimed to maximize the replacement of raw materials in clinker production with calcareous oil shale, while maintaining standard quality characteristics. Utilization of calcareous oil shale in raw state can partially replace both fuel and other raw materials. In this research, belite-rich Portland cement clinker was produced and studied in the laboratory. Grinding time and sulfate content were optimized and cement was prepared. The cement was investigated and its compliance with standard requirements was tested. We showed that oil shale can replace up to 76 % of raw materials in clinker manufacturing, which is sufficient for calcination and final burning in a rotary kiln. This means that oil shale can partially replace fuel, reducing CO₂ emissions during clinker production.