Comprehensive utilization of oil shale: a minireview

Oil shale, a significant fossil energy source, has garnered global attention due to its huge reserves and potential as an alternative to conventional petroleum. This minireview evaluates the comprehensive utilization of oil shale, focusing on its entire lifecycle, from extraction to energy production, treatment of abandoned mines, and subsequent utilization to gain more economic and environmental benefits. In addition, the minireview underscores the necessity of green and high-value utilization of oil shale and its by-products (i.e., semi-coke and ash) to mitigate environmental pollution. To promote comprehensive utilization of oil shale and its by-products, we summarize current knowledge extending beyond traditional energy applications to encompass construction materials, environmental functional materials, and other high-value products. Strategies such as circulating fluidized bed combustion, in situ conversion, and co-combustion and co-pyrolysis with biomass are introduced for efficient resource use. The treatment of abandoned oil shale mines for energy storage and the recovery of trace and rare earth elements are also addressed. The minireview concludes with recommendations for improving testing strategies, assessing environmental impacts, and exploring new applications to ensure green and sustainable development in the oil shale industry.