The Perforation Below the Gas Lift Valve and Deepened Gas Lifting Technology in Carbonate Reservoirs of Tazhong

The carbonate oil and gas reservoirs in the Tazhong I Gas Field are rich in resources, and the type of oil and gas reservoir is a fractured and porous reservoir with strong heterogeneity and poor inter well connectivity. The stable production period of a single well is short, and the degree of pressure maintenance is low. In the later stage of development, gas lift oil recovery technology is often used to develop the reservoir. However, in the later stage of gas lift development, the liquid level in the block decreased rapidly, resulting in a depth of the liquid level in the wellbore lower than the depth of the last stage gas lift valve, leading to empty lifting in the wellbore. Moreover, due to the deep oil and gas reservoir, high hydrogen sulfide content, and high gas-liquid ratio of the Tazhong I Gas Field, the safety risks and high operating costs of well control during well repair operations are high, and some single wells have relatively low recoverable reserves, which seriously restricts the development of the oil and gas reservoir in this block. Therefore, this article proposes a gas lift valve perforation deepening lifting process and calculation method, which can reproduce low liquid level oil and gas reservoirs without using gas lift pipe columns, achieve efficient development of remaining oil and gas resources in low-pressure carbonate rocks, improve the degree of production capacity utilization, and provide technical support for the efficient development of oil and gas reservoirs in Tazhong I Gas Field.