A compositional simulation approach is utilized to compare huff-n-puff gas and solvent injection in a shale gas condensate reservoir. Each injection process is analyzed in terms of the least cost, shortest payback period, smallest injected pore volume and maximized recovery of the condensate components.

Two gases (methane and ethane) and two solvents (methanol and isopropanol) are chosen for the comparison. The reservoir model is calibrated based on available published rock and fluid properties, and history matching is carried out with production data. The model consists of heterogeneities representative of a shale reservoir such as a stimulated rock volume (SRV) and a non-stimulated rock volume (NSRV) that is intersected by a network of natural fractures.

The reference model is used to understand and establish the basic recovery mechanisms of the four injection fluids while highlighting the principal differences between them. The effects of injection pressure, initial reservoir pressure, injection and production time, the gas-condensate composition and nanopore confinement are evaluated. Analysis of the performances of the four injection fluids are based on the total hydrocarbon recovery factors, combining the liquid and gas phases, calculated within the same operation time.

Results demonstrate ethane to be a superior injection fluid with a high recovery factor for most scenarios, accompanied by a relatively higher profit to investment ratio and shorter payback period. Ethane injection recovers the heavy condensate components more efficiently compared to methane and solvent injection for a given gas condensate composition. This advantage is complemented by ethane's capability to equally recover all of other hydrocarbon components from the reservoir. The recovery performance of solvent huff-n-puff for a leaner gas condensate fluid is significantly greater than that for the richer gas-condensate reservoir fluid. The main difference in the optimization of gas and solvent performance is highlighted. Gases require longer injection and production time, whereas solvents perform better with shorter injection time and longer production time.

利用组成模拟方法来比较页岩气凝析油藏中的吞吐正气和溶剂注入。根据最小的成本，最短的投资回收期，最小的注入孔体积和最大的冷凝物回收率来分析每个注入过程。

选择两种气体（甲烷和乙烷）和两种溶剂（甲醇和异丙醇）进行比较。根据可用的公开岩石和流体属性对储层模型进行校准，并与生产数据进行历史匹配。该模型由代表页岩储层的非均质性组成，例如受天然裂缝网络相交的受激岩石体积（SRV）和非受激岩石体积（NSRV）。

参考模型用于理解和建立四种注入液的基本采收机理，同时突出显示它们之间的主要区别。评估了注入压力，初始储层压力，注入和生产时间，气体冷凝物组成和纳米孔限制的影响。四种注入液的性能分析基于总烃采收率，结合了液相和气相，是在相同的操作时间内计算出的。

结果表明，在大多数情况下，乙烷是一种具有较高采收率的优良注入液，同时具有相对较高的利润投资比和较短的投资回收期。对于给定的气体凝析油成分，与甲烷和溶剂注入相比，乙烷注入更有效地回收了重质凝析油组分。乙烷从储层中平均回收所有其他烃组分的能力补充了这一优势。较稀薄的天然气凝析液的溶剂吞吐正压回收性能显着高于较浓的天然气凝析油藏流体的回收率。突出显示了在优化气体和溶剂性能方面的主要区别。气体需要更长的注入和生产时间，