The promotion of enhanced gas recovery (EGR) and CO₂ storage is still shrouded in contention and is not well accepted, due to the excessive in situ CO₂ mixing with the nascent natural gas. This adulterates the recovered CH₄ and thus results in a high sweetening process cost thereby making the technique impractical. This has not only limited the field application of EGR in actual projects to a few trails but renders it uneconomical. This study aims to present, experimentally, alternating N₂ injection as a potential technique for EGR and CO₂ storage in sandstone rock cores. A laboratory core flooding experiment was carried out to simulate a detailed process of unsteady-state methane (CH₄) displacement using Bandera grey core plug. This was carried out at 40 °C, 1500 psig, and 0.4 ml/min injection rate by alternative injection of N₂ and CO₂ in succession designed to suit the application based on optimum operating conditions. The results show that both CO₂ storage capacity and CH₄ recovery improved significantly when gas alternating gas (GAG) injection was considered. The best results were observed at lower N₂ cushion volumes (1 and 2 PV). Therefore, the GAG injection method with N₂ as cushion gas can potentially increase both CO₂ storage and CH₄ recovery of the gas reservoir. This technique if employed will assert the current position and provide vital information for further researches aimed at promoting environmental sustainability and economic viability of the EGR and CO₂ sequestration processes.

由于过量的原位CO ₂与新生天然气混合，促进气体回收（EGR）和CO ₂储存的促进仍在争执中，并且未被很好地接受。这会使掺入的CH ₄掺假，因此导致高甜化工艺成本，从而使该技术不切实际。这不仅将EGR在实际项目中的现场应用限制在少数几个方面，而且使其变得不经济。这项研究的目的是实验性地提出交替注入N ₂作为在砂岩岩心中储存EGR和CO ₂的潜在技术。进行了实验室岩心驱油实验，以模拟非稳态甲烷（CH ₄）使用Bandera灰芯插头的位移。这是通过在40°C，1500 psig和0.4 ml / min的注入速率下，通过交替注入N ₂和CO ₂来进行的，该注入设计为根据最佳操作条件设计成适合该应用。结果表明，当考虑使用交替气体（GAG）注入时，CO _2的储存容量和CH _4的回收率均得到显着改善。在较低的N ₂缓冲体积（1和2 PV）下观察到最佳结果。因此，使用N ₂作为缓冲气体的GAG注入方法可以潜在地增加CO _2的储存量和CH ₄气藏的恢复。如果采用该技术，将确立当前的位置，并为进一步研究提供重要信息，以促进EGR和CO ₂隔离过程的环境可持续性和经济可行性。