关键词: 含水致密气藏, 苏里格气田, 主控因素, 开发风险, 动用对策

Abstract: Sulige Gasfield is an example of successful tight gas development in China. However, with the progress of gas field development, the problem of water production from gas reservoir is gradually prominent. The water-bearing tight gas reservoirs are developed in the western, northeastern and southwestern parts of Sulige Gasfield, with proven gas reserves of trillions of cubic meters, and the large-scale beneficial gas development is facing great challenges. The analysis shows that the produced formation water is dominated by CaCl₂ type and metamorphic ancient sedimentary water, which is divided into three types of free water, capillary water and bound water. The formation and distribution of water-bearing tight gas reservoirs were affected by several factors, such as gas generation intensity, micro structures, reservoir heterogeneity, and fault system, which were generally developed in areas with low gas generation intensity, while gas enrichment areas were located in local positive micro structures. The evaluation results indicate that are multiple risks in the development of water-bearing tight gas reservoirs, including formation water intrusion, low gas rate of single well, low economic returns, high production cost, and HSE and management. As a result, a series of researches should be strengthened, such as sweet spot area prediction in micro structures, gas/water layer logging interpretation and identification, fine description of effective reservoir space, mixed development well pattern of vertical/deviated well +horizontal well, production measures optimization and low-cost production technology, centralized treatment of produced water and prevention of safety and environmental protection issues, and whole-process water intrusion prevention and control and risk management, so as to realize the successful development of water-bearing tight gas reservoirs.