Study On Technologies Of Chemical Sand Control Focusing On Sand Wells In Offshore A Gas Field

With increasing development in this loose sand gas reservoir,some factors such as decreasing pressure,unreasonable production system,water logging in reservoir and so on have contributed some wells to becoming sand ones.Those flowing sands may lead to some perforating intervals being blocked,and they would bring erosion even damages to relative devices,which has some negative effects on safety management.Recently,mechanical sand control including superior quality screen sand control and gravel pack screen sand control is mainly to govern sand from gas wells,and those technologies have effective improvements on sand control when diameter of sand is beyond 90 ?m,but they will behave badly as sand diameter is less than 90 ?m.Hence,it is necessary to study sand control of this gas reservoir.The loose sand formation in A gas reservoir has been investigated with selecting actual gas wells,and some experiments have been performed to study sand controlling.Some results has been gained as followed.(1)The feasibility of chemical sand control in A gas field has been discussed by careful analysis on characteristics for formation material quality,lithology,temperature and pressure and so on,and the sand control character and sand producing condition also have been considered.(2)Injection method has been used to solidify cores,and chemical sand control model evaluation method for gas wells has been built.(3)According to analysis on laboratory experiments,ahead fluid has been sure:water+3%KCl+5%mutual solvent PCS+2%SH discharge aiding agent.It can reduce surface tension effectively on glutenite,which enhances adsorption of sand consolidation agent on surface..(4)YH micro-emulsion water-based solid sand fluid is achieved:8%resin YH-01+12%curing agent YH-02+4%modifier YH-03+0.5%coupling agent YH-04+75.5%diluter(3%NaCl saline water).This recipe has some advantages:lower viscosity,smaller injection pressure,less harmful permeability,longer operation time and so on.(5)A technical project of chemical sand control has been advised to operate in a gas well,which was in practice.