Effects-of-Paraffin-Wax-Precipitation-during-Cold-Water-Injection-in-a高凝油油藏常温注水析蜡研究.pdf

PETROPHYSICS, VOL. 46, NO. 5 (OCTOBER 2005); P. 354–360; 8 FIGURES Effects of Paraffin Wax Precipitation during Cold Water Injection in a Fractured Carbonate Reservoir1 2 2 Dan Maloney and Arvid Østhus ABSTRACT This study investigates potential effects of paraffin were included in waterflood simulations to evaluate pro- wax precipitation while waterflooding oil in an offshore gression of the temper ature front relative to the frac tured car bon ate res er voir using unheated sea wa ter. waterflood front and to predict the effects of reservoir Although ini tial res er voir tem per a ture is 130°C, con tin u- cooling on oil recovery. ous injection of 8°C seawater propagates a cold tempera- Paraffin wax was identified in cores after each labora- ture thermal front from the water injection wells. Paraffin tory test. Wax occurred in masses that were unevenly dis- wax precipitates from the reservoir oil when chilled to tributed in the porous media. Reducing temperature after below 25°C. Could this be problematic with respect to flooding the cores to residual oil saturation Sor improved water injectivity and oil recovery? What are the nature rather than reduced water injectivity. Even though wax and distribution of precipitated wax in this rock? How pre cip i tated when tem per a ture fell below the oil does the chilled-tem per a ture-front prop a gate in rela tion- cloud-point, as temperature was reduced the volume of ship to the wate