Chemical Water Shutoff Practice in Production Wells of Sandstone Oil Reservoirs in Huabei

Three mature methods of chemical water shutoff in oil production wells developed for sandstone oil reservoirs of Huabei oil fields,which are featured by complexity in geologic configuration,multiplicity and variety,large difference in physical characteristics,and low well productivity,are reviewed in this article.The composition and properties of chemical water shutoff agents,the technologies,equipments,and auxiliary measures,and the uses of these methods are presented.These methods are: water shutoff by using a sodium silicate gelling fluid squeezed in a single slug for sandstone reservoirs in Shaheji and Jin-45 block;zonal water shutoff by using crosslinked polymer gel TDP-02 with various pipe strings composed of packers,in particular,for sandstone reservoirs in Menggulin;plugging bottom water by constructing an artificial elastic polymer gel clapboard in the oil/water transition zone of production wells in conglomerate reservoirs of Menggulin.The tendencies of further development are stated.