Preformed Particle Gel for Conformance Control: Transport Mechanism Through Porous Media
Particle gel (PG) is another kind of preformed gel in which bulk gel synthesized in surface facilities is cut into particles and is dried to form xerogel particle at a higher temperature. This process provides a product that is more easily packed and saves transport cost. PG can be carried by produced water into wells, which can save fresh water and protect environment. Preformed PG was successfully synthesized and applied to control excess water production in some mature water-flooded oilfields in China. In microscopic scale, PG propagation through pore throats exhibited six patterns: direct pass, adsorption and retention, deform and pass, snap-off and pass, shrink and pass, and trap. In macroscopic scale, PG propagation through porous medium could be described by three patterns, i.e., pass, broken and pass, and plug. The pattern could be determined by three parameters, i.e., pressure change with time at different tap, particle size of effluent, and residual resistance factor at different segment of a core. Measurements from core-flooding and micro-model experiments showed that a swollen PG particle can pass through a pore throat whose diameter is smaller than its diameter due to the elasticity and deformability of swollen PG. A PG particle could move through a porous medium only if a driving pressure gradient was higher than a threshold pressure gradient. The threshold pressure depended on PG strength, the diameter ratio of particle, and average pore size.
B. Bai et al., "Preformed Particle Gel for Conformance Control: Transport Mechanism Through Porous Media," Proceedings of the SPE - DOE Fourteenth Improved Symposium Oil Recovery: Clean Sweep Strategies (2004, Tulsa, OK), Society of Petroleum Engineers (SPE), Apr 2004.
The definitive version is available at http://dx.doi.org/10.2118/89468-MS
SPE - DOE Fourteenth Improved Symposium Oil Recovery: Clean Sweep Strategies (2004: Apr. 17-21, Tulsa, OK)
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
In-Situ Gelling; Particle Gel (PG); Porous Media; Thermostabilization
Article - Conference proceedings
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