Reservoir Formation Damage Episode 1 Part 8 doc

E, & Civan, E, "Predictability of Formation Damage byModeling Chemical and Mechanical Processes," SPE 23793 paper,Proceedings of the SPE International Symposium on Formation DamageContro

Particulate Processes in Porous Media 157subject to

(8-32)

i cr is the critical shear stress and k e is an erosion rate constant given

by (Khilar and Fogler, 1987):

k' and n are some empirical parameters, which assume k' = \JL and n' = 1

for Newtonian fluids

The critical shear stress, i cr , is a function of the particle stickiness to the surface characterized by the k x constant and the particle concentration

at pore surface (Civan, 1990, 1996):

T =^c« (8-38)

where a is an empirical constant

158 Reservoir Formation Damage

Based on Eqs 8-35 and 8-36, the excess shear stress can be correlatedfor one-dimensional horizontal flow:

The previous studies are mostly limited to one-dimensional Newtonianfluid flow and they typically used (Civan et al., 1989; Khilar and Folger,1987; Gruesbeck and Collins, 1982; Cernansky and Siroky, 1985; Ohenand Civan, 1989, 1990):

(8-40)

In general, for multi-dimensional flow (Civan, 1996)

(8-41)

where if/ is the flow potential and D is the hydraulic tube diameter tensor

for anisotropic media 5 is a unit vector

Particle Transfer Across Fluid-Fluid Interfaces

The driving force for particle transfer between two fluid phases is thewettability of the fluid phases relative to the wettability of the particles.Particles prefer to be in the phase that wets them (Muecke, 1979) (seeFigure 8-9 by Civan, 1994) But, mixed-wet particles tend to remain onthe interface where they are most stable (Ivanov et al., 1986) (see Figure8-10) In the region involving the interface between wetting and non-wetting phases, it can be postulated that particles A in a weaker wettabilityphase-1 first move to the interface and then migrate from the interface

to a stronger wettability phase-2 according to the following consecutiveprocesses (Civan, 1996):

Nonwetting phase - 1 —» Interface —> Wetting phase - 2 (8-42)Therefore, the following power-law rate expressions can be proposed:

Paniculate Processes in Porous Media 159

SOLID-FLUIDINTERFACE

VELOCITYPROFILE

Figure 8-9 Particle retention at solid-fluid and fluid-fluid interfaces and the

velocity profiles in multi-phase systems (after Civan, 1994; reprinted bypermission of the U.S Department of Energy)

i y

FLUID > •';-

•Phase'2-"-•-•••;' •

SOLID .v PARTICLE

•••.••': ••' ' • •; - - • ; \/Phase 1

Figure 8-10 A particle stabilized at a fluid-fluid interface (modified after Ivanov

et al., 1986; reprinted by permission of the author and Academic Press; afterCivan, 1994; reprinted by permission of the U.S Department of Energy)

160 Reservoir Formation Damage

The rate of particle transfer can be expressed per unit volume of the I th

phase according to the following expression:

Amaefule, J O., Kersey, D G., Norman, D L., & Shannon, P M.,

"Advances in Formation Damage Assessment and Control Strategies,"CIM Paper No 88-39-65, Proceedings of the 39th Annual TechnicalMeeting of Petroleum Society of CIM and Canadian Gas ProcessorsAssociation, June 12-16, 1988, Calgary, Alberta, 16 p

Cernansky, A., & Siroky, R., "Deep-bed Filtration on Filament Layers on

Particle Polydispersed in Liquids," Int Chem Eng., Vol 25, No 2,

1985, pp 364-375

Paniculate Processes in Porous Media 161

Chang, F F., & Civan, F., "Modeling of Formation Damage due toPhysical and Chemical Interactions between Fluids and ReservoirRocks," SPE 22856 paper, Proceedings of the 66th Annual TechnicalConference and Exhibition of the Society of Petroleum Engineers,October 6-9, 1991, Dallas, Texas

Chang, F E, & Civan, E, "Predictability of Formation Damage byModeling Chemical and Mechanical Processes," SPE 23793 paper,Proceedings of the SPE International Symposium on Formation DamageControl, February 26-27, 1992, Lafayette, Louisiana, pp 293-312.Chang, F E, & Civan, E, "Practical Model for Chemically Induced

Formation Damage," J of Petroleum Science and Engineering, Vol 17,

Civan, E, "A Multi-Phase Mud Filtrate Invasion and Well Bore FilterCake Formation Model," SPE 28709 paper, Proceedings of theSPE International Petroleum Conference & Exhibition of Mexico,October 10-13, 1994, Veracruz, Mexico, pp 399-412

Civan, E, "Modeling and Simulation of Formation Damage by OrganicDeposition," Proceedings of the First International Symposium onColloid Chemistry in Oil Production: Asphaltenes and Wax Deposition,ISCOP'95, Rio de Janeiro, Brazil, November 26-29, 1995, pp 102-107.Civan, E, "A Multi-Purpose Formation Damage Model," SPE 31101paper, Proceedings of the SPE Formation Damage Symposium, Lafayette,Louisiana, February 14-15, 1996, pp 311-326

Civan, E, Knapp, R M., & Ohen, H A., "Alteration of Permeability by

Fine Particle Processes," J Petroleum Science and Engineering, Vol 3,

Nos 1/2, October 1989, pp 65-79

Dullien, F A L., Porous Media Fluid Transport and Pore Structure,

Academic Press, London (1979), 396 p

Gruesbeck, C, & Collins, R E., "Particle Transport Through Perforations,"

SPEJ, December 1982, pp 857-865.

Gruesbeck, C., R E Collins, "Entrainment and Deposition of Fine

Particles in Porous Media," SPEJ, December 1982, pp 847-856.

162 Reservoir Formation Damage

Hallow, J S., "Incipient Rolling, Sliding, and Suspension of Particles in

Horizontal and Inclined Turbulent Flow," Chem Eng Sci., Vol 28,

1973, pp 1-12

Himes, R E., Vinson, E E, & Simon, D E., "Clay Stabilization in

Low-Permeability Formations," SPE Production Engineering, August 1991,

pp 252-258

Ikoku, C U., & Ramey, Jr., H J., "Transient Flow of Non-NewtonianPower-Law Fluids in Porous Media," Supri-TR-9, Report No E(04-3)1265, U.S Department of Energy (February 1979) 257

Ivanov, I B., Kralchevsky, P A., & Nikolov, A D., "Film and LineTension Effects on the Attachment of Particles to an Interface,"

J Colloid and Interface ScL, Vol 112, No 1, 1986, pp 97-107 Ives, K J., "Deep Bed Filters," in Rushton, A (Ed.) Mathematical Models and Design Methods in Solid-Liquid Separation, 1985 Martinus Nijhoff

Publishers, pp 90-332

Khilar, K C., & Fogler, H S., "Colloidally Induced Fines Migration

in Porous Media," in Amundson, N R and Luss, D (Eds.), Reviews

in Chemical Engineering, Freund Publishing House LTD., London,

England, January-June 1987, Vol 4, Nos 1 and 2, pp 41-108

Khilar, K C., & Fogler, H S., "Water Sensitivity of Sandstones," SPEJ,

February 1983, pp 55-64

Kia, S E, Fogler, H S., & Reed, M G., "Effect of Salt Composition onClay Release in Berea Sandstones," SPE 16254, February 1987.King, R W., and Adegbesan, K O., "Resolution of the Principal For-mation Damage Mechanisms Causing Injectivity and ProductivityImpairment in the Pembina Cardium Reservoir," SPE Paper 38870,Proceedings of the 1997 Annual Technical Conference and Exhibitionheld in San Antonio, Texas, October 5-8, 1997, pp 277-288

Lichtner, Water Resources Research, Vol 28, No 12, December 1992,

pp 3135-3155

McDowell-Boyer, L M., Hunt, J R., & Sitar, N., "Particle Transport

Through Porous Media," Water Resources Research, Vol 22, No 13,

December 1986, pp 1901-1921

Metzner, A B., & Reed, J C., "Flow of Non-Newtonian

Fluids—Corre-lation of the Laminar, Transition, and Turbulent Flow Regions," AIChE J., Vol 1, No 4, 1955, pp 434-440.

Millan-Arcia, E., Civan, F "Characterization of Formation Damage by

Particulate Processes," J Canadian Petroleum Technology, Vol 31,

No 3, March 1992, pp 27-33

Muecke, T W., "Formation Fines and Factors Controlling their Movement

in Porous Media," JPT, April 1979.

Ochi, J., & Vernoux, J.-F., "Permeability Decrease in Sandstone

Reser-voirs by Fluid Injection-Hydrodynamic and Chemical Effects," / of Hydrology, Vol 208, 1998, pp 237-248.

Paniculate Processes in Porous Media 163

Ohen, H A., & Civan, F., "Predicting Fines Generation, Migration andDeposition Near Injection and Production Wells," Proceedings of theFirst Regional Meeting, American Filtration Society, Houston, Texas,October 30-November 1, 1989, pp 161-164

Ohen, H A., & Civan, F, "Simulation of Formation Damage in PetroleumReservoirs," SPE 19420 paper, Proceedings of the 1990 SPE Symposium

on Formation Damage Control, Lafayette, Louisiana, February 22-23,

1990, pp 185-200

Ohen, H A., & Civan, F, "Simulation of Formation Damage in Petroleum

Reservoirs," SPE Advanced Technology Series, Vol 1, No 1, April

1993, pp 27-35

Pautz, J F, Crocker, M E., & Walton, C G., "Relating Water Qualityand Formation Permeability to Loss of Injectivity," SPE 18888 paper,Proceedings of the SPE Production Operations, Oklahoma City, Oklahoma,March 13-14, 1989, pp 565-576

Rushton, A., "Mathematical Models and Design Methods in Solid-Liquid

Separation," NATO ASI, 1985, No 88, Ed A Rushton, Martinus Nijhoff.

Wojtanowicz, A K., Krilov, Z and Langlinais, J P., "Study on theEffect of Pore Blocking Mechanisms on Formation Damage," PaperSPE 16233, presented at Society of Petroleum Engineers ProductionOperations Symposium, Oklahoma City, Oklahoma, March 8-10, 1987,

Chapter 9

Crystal Growth and Scale Formation in Porous Media*

Summary

In this chapter, the inorganic and organic precipitation/dissolutionphenomena, and their effect on the size of the suspended particles andporosity variation are discussed and formulated

Introduction

Civan (1996) describes that:

Injection of fluids and chemicals for improved recovery, and tion of dissolved gases, such as CO2 and light hydrocarbons fromthe reservoir fluids approaching the wellbore during produc-tion, and variation of fluid saturations can alter the temperature,pressure, and composition of the fluids in the near wellbore regionand tubing Consequently, the thermodynamic and chemical balancemay change in favor of precipitate separation, aggregation of preci-pitates, crystal growth, and scale formation Precipitates causeformation damage by changing the wettability and permeability ofpetroleum bearing rock and cause scale formation and clogging intubing and pore throats

Crystal Growth and Scale Formation in Porous Media 165

(SrSO 4 ), magnesium sulfide (MgSO 4 ) originating from mixing sea water

with brine, and rock and brine interactions (Oddo and Tomson, 1994;

Atkinson and Mecik, 1997); ironhydroxide gel (Fe(OH)^ originating

from the acid dissolution and precipitation of iron minerals such as

pyrhotite (FeS), pyrite (FeS 2 ), hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and siderite (FeCO 3 ) (Rege and Fogler, 1989); silicium tetra hydroxide gel (Si(OH) 4 ] originating from the alkaline dissolution and precipitation of

minerals in shaly sandstones such as quartz and kaolinite (Labrid, 1990); andpolymeric substances produced by in-situ gelation (Todd et al., 1993), alcoholinduced crystallization (Zhu and Tiab, 1993), separation of elemental sulfur(Roberts, 1997); and surfactant precipitation (Arshad and Harwell, 1985).Following Oddo and Tomson (1994), precipitation/dissolution reactionscan be symbolically represented by:

Oddo and Tomson (1994) correlated the saturation solubility product,

K sp , empirically as a function of temperature, T, pressure, p, and ionic

strength, 5"., for typical systems Hence, the saturation ratio given by thefollowing equation can be used to determine whether the conditions arefavorable for precipitation (Oddo and Tomson, 1994):

to zero and their deposition at the pore surface and tubing wall isirreversible unless a solvent treatment is applied (Leontaritis et al., 1992):The saturation ratio is given by:

166 Reservoir Formation Damage

(9-3)

where Fs < 1 for undersaturated solution, F s = 1 for saturated solution, and

F s > 1 for supersaturated solution X A is the mole fraction of the dissolved organic in oil and (XA ) S is the organic solubility at saturation conditions.

(X A ) S is predicted using the thermodynamic model by Chung (1992).

Crystallization

Majors (1999) explains that "Crystallization is the arrangement ofatoms from a solution into an orderly solid phase." and "Growth is simplythe deposition of material at growth sites on an existing crystal face."The process is called primary nucleation if there are no crystals present

in the solution to start with and crystallization is occurring for the firsttime Primary nucleation can be homogeneous or heterogeneous (Majors,1999) Homogeneous nucleation occurs inside the solution without contactwith any surface Heterogeneous nucleation occurs over a solid surface.The process is called secondary nucleation if there are already somecrystals present in the system over which further deposition can occur.The schematic chart given in Figure 9-1 by Majors (1999) describes theconcentration-temperature relationship for nucleation As can be seen, theprimary nucleation process requires a sufficiently high concentration of

Figure 9-1 Concentration vs temperature diagram for crystal formation (after

Majors, 1999; reprinted by permission of the Chemical Processing Magazine).

Crystal Growth and Scale Formation in Porous Media 167

supersaturated solution Whereas, secondary nucleation can occur atrelatively lower concentrations above the saturation line The metastableregion represents the favorable conditions for crystal growth (Majors, 1999).The schematic chart given in Figure 9-2 by Majors (1999) describesthe effect of the supersaturation ratio on the crystal growth and nucleationrates Crystal growth rate is a low-order function of supersaturation andcan be represented by a linear relationship, while nucleation rate is a high-order function of supersaturation and requires a more difficult nonlinearrelationship (Majors, 1999) Majors (1999) explains that "Crystal growth

is a dynamic process While most of the crystals in the solution will grow,some may dissolve."

Grain Nucleation, Growth, and Dissolution

The formation of crystalline particulates from aqueous solutions of saltsinvolves a four step phase change process (Dunning, 1969):

1 Alteration of chemical and/or physical conditions to lead to saturation of the solution,

supser-2 Initiation of the first small nuclei of the crystals,

3 Crystal growth, and

4 Relaxation leading to coagulation of crystalline particles

I

NucleationSupersaturation ratio

Figure 9-2 Effect of saturation ration of the crystal growth and nucleation

rates (after Majors, 1999; reprinted by permission of the Chemical Processing

Magazine).

168 Reservoir Formation Damage

The process is called homogeneous or heterogeneous crystal nucleationdepending on the absence or presence, respectively, of some impurities,seed crystals, or contact surfaces, called substrates (see Figure 9-3 byLeetaru, 1996) As stated by Schneider (1997), "Nucleation commonlyoccurs at sites of anomalous point defects on the grain surface, atstructural distortions caused by edge or screw dislocations, or at irregularsurface features produced by dissolution and etching." Because, Schneider(1997) adds, "When nucleation occurs at one of these sites, the freeenergy of the defect, dislocation, or surface irregularity can contribute

to help overcome any energy barrier to nucleation." Also, the mineralgrain surfaces serve as seed for nucleation if the mineral crystal latticestructure matches that of the precipitating substance (Schneider, 1997).The free energy change associated with heterogeneous nucleation at asurface is expressed by (Schneider, 1997):

AG = AGvolume + AG surface + &G strain (9-4)

where &Gstrain is the change of the strain volume free energy of shrinking

of a nucleus

Figure 9-3 SEM photomicrograph of a calcite cement nucleating at a site

in an Aux Vases sandstone sample (after Leetaru, 1996; reprinted by mission of the Illinois State Geological Survey)