压缩空气储能地下盐穴物探关键问题及处理技术

目的]湖北省应城市的世界首个300 MW级压缩空气储能电站是利用应城地下密封性好、容量空间大的已有盐穴作为储气库的。地下盐穴容积、形态和深度等参数条件对压缩空气储能电站的建设可行性起决定性作用。方法]通过应城压缩空气储能电站项目实践,分析总结了高精度三维地震物探方法在探测深部盐穴形态时面临的诸多关键问题和处理技术。结果]在探明地下已有盐穴赋存特征时,三维地震物探观测系统设计应满足高分辨率的需求,CDP网格应满足不低于5 m×5 m的精度,确保目标区覆盖次数大于30次。盐穴三维地震数据处理采用静校正处理技术、叠前去噪技术来提高数据质量。针对不同的激发接收条件采用一致性处理技术,并构建准确的速度场,实现准确深度归位。道积分属性、反射强度属性、甜点属性等在识别盐穴腔体空间展布上有明显优势,边缘检测属性对于腔体边缘刻画及连通性具有较强的指示。结论]通过物探过程中数据处理及资料解释关键技术研究,清晰地探测了盐穴容积、形态、深度等参数,为盐穴工程的开展提供详实可靠的数据支撑。研究盐穴三维地震物探中的关键问题及处理技术,可为地下盐穴型大规模压缩空气储能建设提供参考。

Key Problems and Techniques of Geophysical Exploration in Underground Salt Cavern for Compressed Air Energy Storage

  Introduction  The world′s first 300 MW compressed air energy storage (CAES) power station is in Yingcheng City, Hubei Province, China. The station uses the existing underground salt cavern which is the best of its tight sealing and high capacity as gas storage, The parameters of the underground salt cavern, such as the underground salt cavity volume, shape, and depth, are crucial for the construction feasibility of the CAES power station.   Method  Based on the Yingcheng CAES power station project practice, this paper analyzed and summarized the many key problems and processing techniques of the high precision 3D seismic geophysical exploration methods in detecting deep salt cavity shapes.   Result  For the purpose of proving the occurrence characteristics of existing underground salt cavity, the 3D seismic geophysical exploration observation system shall be designed to meet the high resolution requirements, and the CDP gridding shall have an accuracy of at least 5 m×5 m, in order to make sure the fold number of the target area is more than 30 times. It is indispensable to improve the salt cavern 3D seismic data quality by conducting static correction and pre-stack denoising. Consistency processing technique is used and accurate velocity field is constructed according to different excitation and receiving conditions to realize precise depth homing. We find the track integral attribute, reflection strength attribute and sweetness attribute have an obvious advantage in identifying salt cavern space distribution, while edge detection attribute has a strong indication on cavity border depiction and connectivity.   Conclusion  Through research on key techniques of data processing and interpretation in geophysical exploration, the salt cavity parameters such as volume, shape, and depth are clearly detected to provide detailed and reliable data support for the salt cavern project. Research on the key problems and techniques of the 3D seismic geophysical exploration for the salt cavern can provide reference to the construction of large-scale CAES power stations of underground salt cavern type.