Research Progress,Challenges and Countermeasures in Chemical Water Plugging of Gas Wells
At present,more than 80％of the developed gas fields in China produce water,which seriously affects the productivity of gas wells.Chemical water plugging is an important means to enhance gas recovery of water producing gas reservoir.This paper summarizes the chemical water plugging materials commonly used in gas wells at home and abroad,and discusses the mechanism and adaptability of water plugging.The results show that the polymer and polymer gel achieve disproportionate gas-water permeability reduction(DPR)through resistance effect,inertia effect and lubrication effect.The polymer plugging agent is suitable for medium and high porosity and permeability reservoirs,and its environmental adaptability is improved by pretreatment fluid+modified polymer.Polymer gel is suitable for high temperature,high salinity and fractured water producing gas reservoir.The relative permeability modifier realizes DPR through wettability change,which is suitable for low permeability,dense and high water producing gas reservoirs,but not suitable for fractured gas reservoirs.Functional fluids(functional nanofluids,microemulsion systems,etc.)are designed for specific reservoir conditions(such as condensate gas reservoirs)to achieve DPR through wettability changes;foam gel achieves DPR by Jiamin effect and shunting effect,which is suitable for strong heterogeneity and fractured gas reservoirs.At the same time,this paper analyzes the challenges faced by gas well water control,and further puts forward six gas well water control strategies and research directions,such as adopting different ideas according to the source of water,developing new materials for separating membrane water control,transforming reservoir environment with pretreatment fluid,and integrating moderate water production and water control.The research results of this paper can provide guidance for gas well water plugging practice.
gas wellswater plugging materialwater plugging mechanismadaptabilityseparation membrane
万方数据
维普
