Improvement in filtration properties of water-based drilling fluid by nanocarboxymethyl cellulose/polystyrene core–shell nanocomposite
Journal of Petroleum Exploration and Production Technology
https://doi.org/10.1007/s13202
Improvement in filtration properties of water‑based drilling fluid by nanocarboxymethyl cellulose/polystyrene core-shell nanocomposite
Rahmatallah Saboori 0 1 2 4
Samad Sabbaghi 0 1 2 4
Azim Kalantariasl 0 1 2 4
Dariush Mowla 0 1 2 4
0 Nanotechnology Research Institute, Shiraz University , Shiraz , Iran
1 Nano Chemical Engineering Department, Shiraz University , Shiraz , Iran
2 School of Chemical and Petroleum Engineering, Shiraz University , Shiraz , Iran
3 Samad Sabbaghi
4 EOR/IOR Research Institute, Shiraz University , Shiraz , Iran
Since almost all drilling problems directly or indirectly relate to drilling fluid, improvement in drilling fluid significantly enhances drilling operations. Drilling fluid contains base fluid, suspended solid particles and chemicals. Recently, nanoparticles have been widely recommended for improvement in drilling fluid properties. The main purpose of this study was to improve the rheological and filtration properties of water-based drilling fluid through adding new additive carboxyl methyl cellulose (CMC)/polystyrene core-shell nanocomposite. It compares filtration and rheological behavior of CMC, nanoCMC and core-shell nanocomposite. The core-shell nanocomposite was synthesized by miniemulsion polymerization method, and nanoCMC and core-shell nanocomposite were characterized by scanning electron microscope, transmission electron microscopy, particle size analyzer and thermogravimetric analysis. Fluid loss, mud cake thickness, viscosity, weight and pH of drilling fluid with core-shell nanocomposite additive were compared with conventional CMC (bulk CMC) and nanoCMC particles. Results showed a significant decrease in mud cake thickness and fluid loss when the core-shell nanocomposite was used, as compared with conventional CMC and nanoCMC. Viscosity of three additives has same trend with insignificant change while less yield point is obtained for drilling fluid containing core-shell nanocomposites. Mud weight and pH were almost the same for all three additives. Thus, the core-shell nanocomposite can be an alternative additive to control mud cake thickness and fluid loss while maintaining other main properties in an acceptable range.
Drilling fluid; Core-shell nanocomposite; CMC nanoparticle; Polystyrene; Filtration; Rheology
Introduction
Drilling fluid has many key functions in drilling operations,
and almost all problems encountered in drilling operations
are directly or indirectly related to drilling fluid properties
(Adams 1985; Chilingarian and Vorabutr 1983; Patel 1998;
Plank and Gossen 1991)
. Optimum selection of drilling
fluid is a key factor in minimizing drilling time and cost
(Mokhtari and Ozbayoglu 2010; Salih et al. 2016)
. Due to
cost, environmental issues, water-based drilling fluid is more
preferable and attractive option than oil and synthetic fluids
for drilling oil and gas wells in sensitive areas where oil base
fluids are not desired. Development of high performance and
more environmental friendly water base fluids are desirable
(Salih et al. 2016)
.
Water-based drilling fluid mainly consists of water as
base fluid, inert and reactive solids as additives which still
has many disadvantages including shale instability,
formation damage, poor cake properties and high fluid loss;
recently, nanowater-based fluid has been proposed by
several researchers for overcoming related issues in drilling
fluid such as reducing tor and drag, controlling fluid loss,
minimizing formation damage, improving wellbore
stability and subsequently improving drilling performance. Due
to high surface to volume ratio of nanosized particles, they
can change chemical and physical properties of drilling
fluids with low concentration. Several studied have proven
superiority of NBFs to conventional drilling fluids
(
GarciaOchoa et al. 2000
;
Li et al. 2015
a; Pérez et al. 2004;
Singh
et al. 2010
; Tabzar et al. 2015;
Yu 2015
;
Wang et al. 2016
).
Wang et al. (2011
b) investigated the effect of cross-linked
polystyrene microsphere as a density-reducing agent on
drilling fluid.
William et al. (2014
) studied the effects of CuO and ZnO
nanofluids on thermal, electrical and rheological properties
of the water-based drilling fluid at different pressures. Their
results showed that addition of nanoparticles increases
thermal and electrical properties of drilling fluid by about 35%.
In addition, increasing nanoparticle concentration caused
increase in the thermal and electrical properties.
Sadeghalvaad and Sabbaghi (2015)
reported decrease in filtration
and increase in mud viscosity when TiO2/polyacrylamide
nanocomposite used as additive to water-based drilling fluid.
Sensoy et al. (2009
) observed reduction in absorbed
water by shale from 16 to 72% when silica nanoparticle
was used.
Ragab and Noah (2014)
showed that adding
silica nanoparticles in drilling fluid caused a decre (...truncated)