CO₂驱油技术作为CO₂捕集、利用与封存技术的重要组成部分，在提高石油采收率的同时可实现规模化封存，被国内外广泛应用。然而，该技术在注入、驱油封存、采出等环节中存在多种泄漏风险。目前，国内外相关项目在监测方面多集中于储层和盖层，缺乏系统性的生态环境监测。张家垛油田自2014年开始注CO₂开发，累计注气量19.53×10⁴ t，累计增油量5.16×10⁴ t，提高采收率15.22%，阶段换油率3.78，取得了显著的开采成效。以张家垛油田的CO₂驱油封存项目为例，在分析CO₂驱油与封存泄漏可能性的基础上，建立了涵盖地下水体、土壤、大气的全方位和多指标的CO₂泄漏监测体系，实时监测并预警CO₂泄漏信息。根据一年多的连续监测，结果表明：张家垛地下水中CO₂质量浓度稳定保持在5 712 mg/m³左右，pH值接近中性，且电导率稳定在1.343~1.347 µS/cm；土壤CO₂质量浓度、pH值、电导率均相对稳定，3个层位的大气CO₂质量浓度呈现周期性变化且与土壤的变化趋势一致，平均介于730~780 mg/m³，指标接近低纬度区域常规大气CO₂质量浓度。综合多项监测指标结果，表明张家垛油田目前并未发生CO₂泄漏情况。该监测体系的成功应用不仅为张家垛油田的持续开发提供了科学依据，也为其他类似项目在环境监测方面提供了经验和借鉴，进一步推动了CO₂驱油技术的安全和可持续发展。

As a critical component of Carbon Capture, Utilization, and Storage (CCUS) technologies, CO₂-enhanced oil recovery (CO₂-EOR) has been widely used both domestically and internationally. This technology not only improves oil recovery but also enables large-scale CO₂ sequestration. However, potential CO₂ leakage risks exist throughout the processes of CO₂ injection, displacement, sequestration, and production. Existing monitoring practices in domestic and international projects primarily focus on reservoirs and caprocks, with limited attention paid to systematic ecological environmental monitoring. CO₂-EOR development commenced in the Zhangjiaduo oilfield in 2014. As of now, a cumulative total of 195,300 tonnes of CO₂ has been injected, resulting in an incremental oil production of 51,600 tonnes. The oil recovery rate was improved by 15.22%, and the phase oil replacement ratio reached 3.78, indicating remarkable stimulation effectiveness. Based on the Zhangjiaduo CO₂-EOR and sequestration project, a comprehensive 3D monitoring system was developed, integrating multiple indicators across groundwater, soil, and atmosphere to enable real-time monitoring and early warning of CO₂ leakage. After over one year of continuous monitoring, the results showed that the CO2 mass concentration in Zhangjiaduo groundwater remained stable at about 5,712 mg/m³, with a near-neutral pH and stable electrical conductivity ranging from 1.343 to 1.347 μS/cm. The CO₂ mass concentration, pH, and conductivity in the soil also remained relatively stable. Atmospheric CO₂ concentrations at three different altitudes exhibited periodic fluctuations consistent with soil data, averaging between 730 and 780 mg/m³, which aligns with typical atmospheric CO₂ levels in low-latitude regions. These multi-parameter monitoring results indicate that no CO₂ leakage has occurred in the Zhangjiaduo oilfield to date. The successful application of this monitoring system has provided robust scientific support for the sustained development of the field. Moreover, it offers practical insights and references for environmental monitoring in similar projects, contributing to the safe and sustainable advancement of CO₂-EOR technologies.