多夹层盐矿全溶腔沉渣储气能力评价实验

Experiments on gas storage capacity assessment of full-cavern sediments in multi-interlayer salt mine

中国大部分盐矿为高杂质多夹层盐矿,极端条件下水采形成的沉渣几乎填满盐腔。为评价此类盐矿沉渣储气模式建库的可行性,以山东大汶口盐矿为例开展全溶腔沉渣储气能力实验研究。首先,制备代表该地区的沉渣样本,开展压实条件下单腔沉渣注气排卤实验,得出沉渣储气空隙率达45.2%。其次,开展U形腔注气排卤方式优选实验,确定钻水平排卤井至U形腔底部的最优注气排卤方式,并给出现场实施方案。最后,建立全溶腔沉渣储气模型,根据实验结果和现场数据估算得到大汶口B5井组的储气体积为30.7×10^(4)m^(3)。结果表明:该地区沉渣储气能力较好,目标井组具有较大的储气体积,沉渣储气模式建库具有一定的可行性。研究结果可为大汶口盐矿及同类高杂质多夹层盐矿建库提供借鉴与参考。(图9,表3,参22)

Most salt mines in China are characterized by high impurity and multi-interlayer,and the salt cavern is almost filled with sediments from solution mining under extreme conditions.In order to evaluate the feasibility of building sediment gas storage in this kind of salt mine,an experimental study on the gas storage capacity of full-cavern sediments was carried out based on the Dawenkou salt mine in Shandong Province.Firstly,the representative sediment samples of this region were prepared,and the experiments of sediment gas injection and brine discharge in a single cavern under compaction conditions were carried out.It was found that the void ratio among the sediments for gas storage was up to 45.2%.Secondly,the optimization experiment was carried out for gas injection and brine discharge by the U-shaped cavern,and thus the optimal gas injection and brine discharge mode of drilling a horizontal brine discharge well to the bottom of the U-shaped cavern was determined,with the on-site implementation scheme provided.Finally,a gas storage model was established for the full-cavern sediments.The gas storage volume of well group B5 was estimated to be 30.7×10^(4)m^(3)according to the experimental results and field data.The results show that the sediments in this area have good gas storage capacity,the target well group has a large gas storage volume,and it is feasible to some degree to build sediment gas storage.Generally,the study results could provide a reference for the construction of gas storage in the Dawenkou salt mine and other such high-impurity multi-interlayer salt mines in China.(9 Figures,3 Tables,22 References)