FLUORESCENT TAGS FOR DETECTION OF SWELLABLE POLYMERS

摘要

The invention is directed to stable crosslinked swellable fluorescently tagged polymeric microparticles, methods for making same, and their various uses. A particularly important use is as an injection fluid in petroleum production, where the expandable polymeric particles are injected into target zone and when the heat and/or suitable pH of the target zone cause degradation of the labile crosslinker and the microparticles expand. The swelled polymer diverts water to lower permeability regions and improves oil recovery. The tags allow monitoring of the presence and concentration of the tagged microparticles and ultimately allow evaluation of the performance of such treatments. Detection of polymeric microparticles in producing wells can be instructive for teaching about the character and extent of thief zones in the subsurface. Better knowledge of the reservoir flow will enable improved application of the gel treatments, improved oil recovery, and allow improved forecasting using simulation modeling.

主权项

1. A composition comprising expandable polymeric particles, said particles having a covalently attached fluorescent tag and having anionic sites and being crosslinked with both labile crosslinkers and stable crosslinkers, said particles combined with a fluid and a cationic crosslinker that is capable of further crosslinking the particle on degradation of the labile crosslinker so as to form a gel.