Particulate Processes in Porous Media
There are three primary sources of fine particles in petroleum bearing formations:
1. Invasion of foreign particles carried with the fluids injected for completion, workover, and improved recovery purposes,
2. Mobilization of in-situ formation particles due to the incompatibility of the fluids injected into porous media and by various rock-fluid interactions, and
3. Production of particulates by chemical reactions, and inorganic and organic precipitation.
Fluids injected into petroleum reservoirs usually contain iron colloids produced by oxidation and corrosion of surface equipment, pumps, steel asing, and drill string (Wojtanowicz et al., 1987). Brine injected for waterflooding may contain some fine sand and clay particles. Mud fines can invade the formation during overbalanced drilling. These are some examples of the externally introduced particles. Petroleum bearing formation usually contains various types of clay and other mineral species attached to the pore surface.
These species can be released by colloidal forces or mobilized by hydrodynamic shear of the fluid flowing through porous media. Fine particles can also be generated by deformation of rock during compression and dilatation. This is due to variation of the net overburden stress and loss of the integrity of rock grains.
Fine particles are unleashed and liberated because of the integrity loss of rock grains by chemical dissolution of the ementing materials in porous rock, such as by acidizing or caustic flooding. These are the typical internal sources of indigenous fine particles. Paniculate matter can be produced by various chemical reactions such as the salt formation reactions that occur when the seawater injected for waterflooding mixes with the reservoir brine, and formation of elemental sulfur during corrosion. Paniculate matter can also be produced by precipitation due to the change of the thermodynamic conditions and of the composition of the fluids by dissolution or liberation of light gases (Amaefule et al., 1988). These are typical" mechanisms of particle production in porous media. Once entrained by the fluids flowing through porous media, the various particles migrate by four primary mechanisms (Wojtanowicz et al., 1987):
1. Diffusion
2. Adsorption
3. Sedimentation
4. Hydrodynamics
The transport of the fine particles are affected by six factors (Wojtanowicz et al., 1987):
1. Molecular forces
2. Electrokinetic interactions
3. Surface tension
4. Fluid pressure
5. Friction
6. Gravity
As the fine particles move along the tortuous flow pathways existing in porous media, they are captured, retained, and deposited within the porous matrix. Consequently, the texture of the matrix is adversely altered to reduce its porosity and permeability. Frequently, this phenomena is referred to as formation damage measured as the permeability impairment.
Particulate Processes
The various particulate processes, can be classified in two groups as the internal and external processes.
The external processes occur over the formation face and are discussed in this article. The internal processes occur in the porous media and can be classified in three groups as (Civan, 1990, 1994, 1996):
1. Pore Surface Processes
a. Deposition
b. Removal
2. Pore Throat Processes
a. Plugging (screening, bridging, sealing)
b. Unplugging
3. Pore Volume Processes
a. In-Situ Cake Formation
b. In-Situ Cake Depletion
c. Migration
d. Generation and Consumption (chemical reactions, rock deformatio and crushing, liberation of fine particles by chemical dissolution of cement, coagulation/disintegration)
e. Interphase Transport or Exchange
The net amount of particles deposited in porous media is expressed by: Instantaneous amount of particles in porous matrix = initial amount of particles in porous matrix + net amount of particles deposited on pore surface + net amount of particles deposited behind pore throats.
The fundamental particle generation mechanisms are:
1. Hydrodynamic mobilization
2. Colloidal expulsion
3. Liberation of particles due to the loss of integrity of rock grains
by chemical dissolution of cement or by rock compression, crushing, and deformation
4. Chemical and physico-chemical formation
The fundamental particle retention mechanisms are:
1. Surface deposition (physico-chemical)
2. Pore throat blocking (physical jamming)
3. Pore filling and internal filter cake formation (physical)
4. Screening and external filter cake formation (physical)
References
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 Technical Meeting of Petroleum Society of CIM and Canadian Gas Processors Association, 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.
Chang, F. F., & Civan, F., "Modeling of Formation Damage due to Physical and Chemical Interactions between Fluids and Reservoir Rocks," SPE 22856 paper, Proceedings of the 66th Annual Technical Conference and Exhibition of the Society of Petroleum Engineers, October 6-9, 1991, Dallas, Texas.
Chang, F. E, & Civan, E, "Predictability of Formation Damage by Modeling Chemical and Mechanical Processes," SPE 23793 paper, Proceedings of the SPE International Symposium on Formation Damage Control, 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, No. 1/2, February 1997, pp. 123-137.
Civan, E, "A Generalized Model for Formation Damage by Rock-Fluid Interactions and Particulate Processes," SPE Paper 21183, Proceedings of the SPE 1990 Latin American Petroleum Engineering Conference, October 14-19, 1990, Rio de Janeiro, Brazil, 11 p.
Civan, E, "Evaluation and Comparison of the Formation Damage Models," SPE Paper 23787, Proceedings of the SPE International Symposium on Formation Damage Control, February 26-27, 1992, Lafayette, Louisiana, pp. 219-236.
Civan, E, "Predictability of Formation Damage: An Assessment Study and Generalized Models," Final Report, U.S. DOE Contract No. DE-AC22- 90BC14658, April 1994.
Civan, E, "A Multi-Phase Mud Filtrate Invasion and Well Bore Filter Cake Formation Model," SPE 28709 paper, Proceedings of the SPE International Petroleum Conference & Exhibition of Mexico, October 10-13, 1994, Veracruz, Mexico, pp. 399-412.
Civan, E, "Modeling and Simulation of Formation Damage by Organic Deposition," Proceedings of the First International Symposium on Colloid 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.
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-Newtonian Power-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 Line Tension 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 on Clay Release in Berea Sandstones," SPE 16254, February 1987.
King, R. W., and Adegbesan, K. O., "Resolution of the Principal Formation Damage Mechanisms Causing Injectivity and Productivity Impairment in the Pembina Cardium Reservoir," SPE Paper 38870, Proceedings of the 1997 Annual Technical Conference and Exhibition held 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—Correlation 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 Reservoirs by Fluid Injection-Hydrodynamic and Chemical Effects," /. of Hydrology, Vol. 208, 1998, pp. 237-248.
Ohen, H. A., & Civan, F., "Predicting Fines Generation, Migration and Deposition Near Injection and Production Wells," Proceedings of the First 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 Petroleum Reservoirs," 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 Quality and 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 the Effect of Pore Blocking Mechanisms on Formation Damage," Paper SPE 16233, presented at Society of Petroleum Engineers Production Operations Symposium, Oklahoma City, Oklahoma, March 8-10, 1987, pp. 449-463.
Wojtanowicz, A. K., Krilov, Z. and Langlinais, J. P., "Experimental Determination of Formation Damage Pore Blocking Mechanisms," Trans, of the ASME, Journal of Energy Resources Technology, Vol. 110, 1988, pp. 34-42.
