Natural gas has become a core component of the global clean energy transition, and shale condensate gas reservoirs represent a high-value unconventional resource critical to improving national energy security, especially for countries with a coal-dominated energy mix like China. This paper reviews the current status of gas injection and energy supplement technologies for shale condensate gas reservoirs, focusing on key technical challenges and recent research advances. First, it outlines the unique hurdles of shale condensate gas development, including ultra-low reservoir porosity/permeability, complex nanopore-induced phase behavior alterations, compositional gradients with depth, and retrograde condensation damage during pressure depletion. Then, it systematically summarizes progress in four core research areas: (1) development methods such as gas injection huff-n-puff, which has been proven to boost condensate oil recovery by 15%–20% in field simulations; (2) the nano-confinement effect, which modifies fluid critical properties and diffusion coefficients (reducing effective diffusion by 10²–10⁴ times at low porosities) and enhances CO₂ miscibility in oil phases; (3) compositional gradient modeling, which is shown to prevent significant errors in reserve estimation (up to 54% overestimation of crude volume if ignored); and (4) fractured reservoir simulation, particularly the evolution from discrete fracture models (DFM) and embedded discrete fracture models (EDFM) to the projection-based embedded discrete fracture model (pEDFM), which addresses EDFM’s limitations in handling low-permeability fractures. Finally, the paper proposes an innovative numerical simulation method integrating the general pEDFM with the commercial simulator CMG, which retains pEDFM’s computational accuracy for complex fracture networks while avoiding the high cost of developing custom nonlinear solvers. This review provides a comprehensive theoretical framework for efficient and sustainable shale condensate gas reservoir development, supporting energy security and the global energy transition.
Keywords: Shale condensate gas reservoir; Component gradient; Nano-confinement effect; Projection-based embedded discrete fracture model (pEDFM); Gas injection and energy supplement
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