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Keywords
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Casing, Cement, Gilsonite, HPHT, Nanoparticle, Oil Well.
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Abstract
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Proper annular sealing is imperative for isolating wellbores, preventing leaks to the surface, and
protecting groundwater during oil drilling operations. Cementing between the casing and borehole is
crucial, yet cement failures potentially risk disastrous leaks and massive economic losses for exploration
and production companies. Novel additives like Gilsonite nanoparticles (NPs) present a promising
solution to enhance cement integrity. This study investigated the effects of incorporating Gilsonite
nanoparticles on cement performance under conditions mimicking typical downhole environments.
Cement slurries were prepared with a 0.44 water-to-cement ratio and 2% calcium chloride by weight of
cement (BWOC). The concentration of Gilsonite NPs varied from 0.01 to 0.04% BWOC. The slurries
were tested for rheology, morphology, crystallization, and compressive strength following American
Petroleum Institute guidelines and compared to the base slurry. Significant cement property
improvements were achieved with Gilsonite NPs. The compressive strength increased from 4777 psi
(base) to 7306 psi with 0.04% BWOC Gilsonite after curing at 100°C and 1000 psi, representing a
substantial 53% improvement. This can be attributed to enhanced crystallization and durability
introduced by the NPs in the cement matrix. Overall, the favorable cement properties with minimal
nanoparticle loading highlight the promise of Gilsonite NPs for application in oil well cementing. This
could enable long-term cement sheath integrity over decades of well life, preventing leakage and
associated consequences. Further work should examine performance following accelerated age testing.
With further confirmation, companies can leverage Gilsonite to safeguard future drilling assets.
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