储气库水平井氮气加压射孔升压时间研究

Study on the Rising Pressure Time at Nitrogen Pressuring Perforation to Horizontal Well of Gas Storage

水平井射孔技术在储气库建设中起着非常重要的作用,氮气加压射孔为长水平段的射孔作业提供了保障。其中,氮气正压射孔集正压射孔、负压反向冲击和气体压裂为一体,可提高产能和解除污染,在水平井射孔中得到广泛应用。氮气正压射孔的关键在于氮气加压值的确定。因此,研究加压射孔的升压时间变得尤为重要。通过液氮车同时向油管和套管注氮气和液氮车向套管注氮气,油管密封,以及套管打液氮,快到最低点火压力时,泵车和液氮车同时打压点火的3种方式,建立不同方式下最低点火压力到最高点火压力的升压时间模型。结合水平井各项参数,选择套管打液氮,快到最低点火压力时,泵车和液氮车同时打压点火的方式为目前最优方案,为水平井氮气加压射孔提供一定的理论依据。

Perforation technology to Horizontal well plays a very important role in the gas storage construction,and Nitrogen pressuring perforation provides a guarantee for the perforating operation with long horizontal section. Among those perforating methods,nitrogen positive-pressure perforating tech,combing with positive-pressure perforating,negative pressure reverse impact and gas fracturing,improves productivity and removes pollution,and has widely usages in perforation of the horizontal well. The key work for nitrogen positive-pressure perforating is to determine nitrogen pressure value. Therefore,study on the rising pressure time for pressure perforating is particularly important. Three ways are introduced that are the nitrogen being injected into tubing and casing simultaneously,nitrogen truck pumped into casing,and tubing being seal,and the finally of liquid nitrogen being injected from casing,when coming into minimum ignition pressure,meanwhile pump truck and liquid nitrogen car are pressuring ignition,the rising pressure time models of minimum ignition pressure to maximum ignition pressure are established in different ways. Combing various parameters of horizontal well,the third way is selected to the most optimal scheme at present,which gives some theoretical basis for nitrogen pressure perforating of horizontal well.