摘要
针对目前国内盐矿普遍发育厚夹层的问题,通过室内实验、数值模拟和现场试验,分析厚夹层是否可以垮塌,以实现上下盐层连通,扩大单腔储气空间。分析夹层的水溶机理、水浸后力学参数变化规律后发现:水浸后夹层呈蜂窝状溶解且产生裂缝,利于剥落,剥落残渣占据空间较小;水浸后夹层力学强度明显降低,易发生破坏,有利于夹层垮塌。利用夹层垮塌临界跨度计算模型可预测夹层垮塌时机,通过数值模拟获得了厚夹层垮塌规律,表明夹层厚度越小,夹层埋深、腾空跨度和盐腔高度越大,夹层垮塌的可能性越大。提出了"充分浸泡夹层、二次建槽"的设计思路,针对某储气库12 m厚夹层进行造腔试验设计,并在2口井进行了现场试验,表明厚夹层可以垮塌,且增加了造腔高度,提高了单腔工作气量,具有技术和经济可行性。
Aiming at the current problem that thick sandwiches are commonly developed in domestic salt mines, this study investigated whether thick sandwiches would collapse to allow connection of salt deposits above and below, consequently increase leaching height and expand single cavern capacity by laboratory experiments, numerical simulation and field tests. The analysis of water-soluble mechanism and changing patterns of mechanical parameters of sandwich layers after water immersion shows that： after water immersion, sandwiches dissolve into honeycomb structure with cracks that easily flake, and the residues occupy small space; after water immersion, mechanical strength of sandwiches decrease greatly, susceptible for failure and collapse. Based on the calculation model for critical limited span, the collapse timing was predicted. In addition, laws of thick sandwiches collapse were obtained by numerical simulation, which indicate that the smaller the thickness, the larger the depth, the larger the limited span and storage height of the sandwiches, the more likely the sandwich will collapse. The design idea of ＂full immersion and secondary cavity construction＂ was proposed, and cavern leaching design for a 12 meter thick sandwich in a gas storage was made, and tests on two wells were conducted. The results prove that thick sandwiches could collapse, increasing leaching height and single cavity capacity, and the technology is technologically and economically feasible.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2017年第1期137-143,共7页
Petroleum Exploration and Development
基金
中国石油重大科技专项"地下储气库地质与气藏工程关键技术研究与应用"(2015E-4002)
关键词
盐穴储气库
厚夹层
夹层垮塌
水溶机理
水浸力学参数
造腔设计
造腔试验
salt-cavern storage
thick sandwich
sandwich collapse
water-soluble mechanism
mechanical parameter after water immersion
cavern leaching design
cavern leaching experiment
