US 5,293,939 A · Formation treating methods

Abstract

Disclosed are methods for treating wells to form a permeable barrier around the well for consolidating unconsolidated mineral particles such as sand in a subterranean petroleum formation penetrated by a well, or for forming an impermeable barrier for fluid entry control, or for plugging the well for abandonment. A fluid containing a polymerizable resin such as furfuryl alcohol oligomer or monomer, a polar organic diluent such as butyl acetate a dense solvent having density greater than the resin density, and an oil soluble acid catalyst to cause polymerization of the resin at formation temperatures is prepared. The dense solvent is bromobutane, bromobenzene, furfural, tetrachloroethane, tetrachloroethylene, tetrabromoethane, 1,2,4 trichlorobenzene and 1,2,3 tribromopropane or mixtures thereof. The amount of dense solvent is selected to ensure that the treating fluid density is greater than the density of the formation fluid, preferably at least 10 greater than the density of the formation fluid.

Claims37

Dependent claims

A method for treating a well penetrating a subsurface formation and in fluid communication with at least a portion of the subsurface formation, the temperature of the formation and the density of the formation fluid being known or determinable, comprising:

(a) providing a consolidating treating fluid comprising a resin capable of being acid catalyzed to polymerize in the formation, a polar organic diluent for the resin, a predetermined concentration of dense solvent whose density is greater than the density of the resin, and a predetermined concentration of an oil soluble acid catalyst capable of causing polymerization of the resin at formation temperatures in from 1 to 24 hours, said acid having a pK in the range of 0.4 to 6.0;
(b) injecting said fluid into the formation to enter and saturate at least a portion of the formation adjacent to the well;
and
(c) allowing the injected fluids to remain in the formation for at least four hours to accomplish at least partial polymerization of the resin, forming a polymerized resin-sand mass around the wellbore.

1 more element

Dependencies are inferred from the claim text.

Formation treating methods

Life of this patent

Formation treating methods

Life of this patent

Abstract

Claims37