低渗产水气井间歇开采制度研究

Study of Intermittent Production System for Water-producing Gas wells with Low Permeability

对于低渗气井,一方面,由于产层渗透率低,产量低,采用常规连续排水采气工艺和优化工作制度难以达到理想的排水采气效果;另一方面,低渗气井连续开采过程中,井口气嘴难以达到临界流生产状态,气井产能和携液能力受到干线外输压力的影响较大,特别是对于没有增压设备,依靠井网本身的压力外输的气田。为此,结合我国低渗气井生产实际,根据低渗气井的压力变化规律,系统建立地层产能和压力下降和恢复模型,确定合理的开关井制度,确保低渗低产气井的合理开采和科学管理,对低渗气井的潜力发挥、提高排水采气效果和最终采收率,以及增强气田管网气外输能力具有非常重要的指导意义。

For low permeability gas wells,because reservoir permeability and production were low,it was hard to obtain ideal effect on gas drainage and recovery by using conventional drainage technology and optimized operation system on the one hand,on the other hand,in the continuous producing process of low permeability gas well,the critical productive state could not be reached by gas nipple on the wellhead,and productivity and fluid carrying ability of the gas wells were subjected to trunk pipeline pressure significantly,especial for the gas fields without booster equipment and oil transporting by well network pressure.Therefore,in combination with the actual conditions of low permeability gas wells in China,according to the pressure changing rules,a model of gas well production and pressure dropping and restoring was established.The rational intermittent production system is determined,by which reasonable gas recovery and scientific management are ensured.It is of significant for tapping the potential,enhancing drainage efficiency and ultimate recovery,and reinforcing the pipeline network transporting capacity for the low permeability gas wells.