Tracer compositions
A method for tracing gas flow in a hydrocarbon reservoir with compositions including a degradable polymer and a detectable component. An exemplary method includes introducing a tracer composition at a first location in the reservoir, contacting the tracer composition with the reservoir to hydrolyze the degradable polymer, and detecting a degraded tracer composition including the hydrolyzed polymer and the detectable component in a gas sample collected at a second location in the reservoir.
1 . A method of tracing gas flow in a hydrocarbon reservoir, comprising:
introducing a tracer composition at a first location in the reservoir, wherein the tracer composition comprises a degradable polymer and a detectable component;
contacting the tracer composition with the reservoir to hydrolyze the degradable polymer; and
detecting a degraded tracer composition in a gas sample collected at a second location in the reservoir, wherein the degraded tracer composition comprises the hydrolyzed polymer and the detectable component;
wherein the detectable component comprises:
a fluorescent dye; and
a metal oxide.
2 . The method of claim 1 , wherein the degradable polymer comprises a thermoplastic.
3 . The method of claim 2 , wherein the thermoplastic comprises a poly(lactic acid).
4 . The method of claim 1 , wherein the degradable polymer comprises a thermoplastic polyester elastomer.
5 . The method of claim 4 , wherein the thermoplastic polyester elastomer comprises a block copolymer comprising a hard segment and a soft segment.
6 . The method of claim 5 , wherein the hard segment comprises ethylene terephthalate, propylene terephthalate, butylene terephthalate, or any combination thereof.
7 . The method of claim 5 , wherein the soft segment comprises a polyether, a polyester, a polycarbonate, or any combination thereof.
8 . The method of claim 7 , wherein the soft segment comprises a polyether, and the polyether comprises a polyoxyalkylene glycol.
9 . The method of claim 1 , wherein the fluorescent dye is detectable in the visible spectrum.
10 . The method of claim 9 , wherein the fluorescent dye comprises a xanthene dye.
11 . The method of claim 10 , wherein the xanthene dye comprises a rhodamine dye.
12 . The method of claim 1 , wherein the metal oxide comprises an aluminum oxide.
13 . The method of claim 12 , wherein the aluminum oxide comprises aluminum hydroxide.
14 . The method of claim 1 , wherein the tracer composition comprises an extrudate of the degradable polymer and the detectable component.
15 . The method of claim 1 , wherein the tracer composition comprises particles having an average size of at least about 5 mm.
16 . The method of claim 15 , wherein the particles of the tracer composition comprise pellets or fibers.
17 . The method of claim 16 , wherein the particles comprise fibers having an average length of at least about 4 mm.
18 . The method of claim 15 , wherein the degraded tracer composition comprises particles having an average size of less than about 2 mm.
19 . The method of claim 18 , wherein the particles of the degraded tracer composition comprise a powder.
20 . The method of claim 1 , wherein introducing the tracer composition comprises pumping a stimulation fluid comprising the tracer composition into the reservoir at the first location.
21 . The method of claim 20 , wherein the stimulation fluid comprises an acid.
22 . The method of claim 1 , wherein the second location comprises a gas pipeline.
23 . The method of claim 1 , wherein detecting the degraded tracer composition comprises capturing the degraded tracer composition on a filter.
24 . The method of claim 1 , wherein detecting the degraded tracer composition comprises detecting the fluorescent dye with a fluorometer.
25 . The method of claim 1 , wherein detecting the degraded tracer composition comprises detecting the metal oxide with an X-ray fluorescence spectrometer.