Drag reduction behavior of hydrolyzed polyacrylamide/polysaccharide mixed polymer solutions—effect of solution salinity and polymer concentration

2017 ◽  
Vol 56 (7-8) ◽  
pp. 683-694 ◽  
Author(s):  
Mehdi Habibpour ◽  
Samyukta Koteeswaran ◽  
Peter E. Clark
2021 ◽  
Vol 10 (2) ◽  
pp. 23
Author(s):  
Ahmed Kamel

Previous work has tied the drag reduction properties of polymer solutions to type and concentration of salts, rather than its ionic strength, although it is a more extensive parameter to investigate the effects of salt contents on fluids behavior. The current study aims at investigating the relationship between ionic strength and drag reduction characteristics of polymer solutions when flowing in straight tubing. Nalco ASP-700 and ASP-820, two common anionic AMPS copolymers, are examined with various salts (2% KCl, 4% KCl, and synthetic seawater). Flow tests were conducted using a small-scale flow loop that includes a straight tubing with an outside diameter of 1.27 cm and a length of 4.57 m. It has been found that drag reduction performance of polymer solutions is well correlated with ionic strength, rather than salt type and/or concentration. With high ionic strength, lower drag reduction is noticed despite of the reduced salt concentration. Nevertheless, at higher Reynolds number, the effects of ionic strength minimizes. Both polymer solutions exhibit effective drag reduction characteristics and their behavior is greatly affected by polymer type, shear rate, and salt content. Correlations, with acceptable confidence level, between drag reduction ratio and solutions ionic strength are proposed. The correlations are strongly recommended to investigate the effects of salt types and/or concentrations, represented by its ionic strength on drag reduction behavior of polymer solutions in straight tubing.


1977 ◽  
Vol 17 (02) ◽  
pp. 111-121 ◽  
Author(s):  
J.G. Dominguez ◽  
G.P. Willhite

Abstract Retention and flow characteristics of a solution containing Pusher 700, a high-molecular-weight, partially hydrolyzed polyacrylamide, were studied partially hydrolyzed polyacrylamide, were studied in an 86-md core made by compacting Teflon powder. The quantity, of polymer retained during linear displacement experiments ranged from 10 to 21 mu gm/gm for polymer concentrations of 100 to 500 ppm in 2-percent NaCl solutions. Nearly all retention ppm in 2-percent NaCl solutions. Nearly all retention was attributed to mechanical entrapment because of low polymer adsorption on the Teflon surface. Flow rate affected polymer retention. In increase in velocity was accompanied by polymer retention. Polymer was expelled when the flow rate was Polymer was expelled when the flow rate was reduced. Inaccessible pore volume was about 19 percent of the total pore volume. percent of the total pore volume.Resistance factors in different sections of the core ranged Pam 2 to 10 /or solutions of 100 to 500 ppm polymer concentration in 2-percent NaCl. ppm polymer concentration in 2-percent NaCl. Permeability reduction resulting from polymer Permeability reduction resulting from polymer retention produces the resistance factor in most of the core at a velocity of 3.2 ft/D. Resistance factors in the Teflon cores were two to three times lower than those reported for natural porous media where polymer is also retained by adsorption. Introduction The search for a low-cost, effective mobility control agent is currently focused on dilute aqueous solutions containing partially hydrolyzed polyacrylamides or polysaccharides. Rheological polyacrylamides or polysaccharides. Rheological properties have been studied, including the properties have been studied, including the effects of polymer concentration, shear rate, electrolyte concentration, and type of electrolyte. Correlation of rheological data and models with the flow behavior of polymer solutions in porous media has been complicated by the many interactions that occur between the complex porous matrix and the polymer solutions. Some data have been correlated using non-Newtonian rheological models to describe the variation of fluid viscosity with the apparent shear rate that the fluid experiences as it flows through the tortuous paths in porous media. These correlations have adjustable parameters determined from the particular set of parameters determined from the particular set of data used to develop the correlation. Investigators studying partially hydrolyzed polyacrylamide solutions observed apparent polyacrylamide solutions observed apparent viscosities 5 to 20 times the values measured in a conventional viscometer at the shear rates believed to exist in the porous media. These viscosity increases were not anticipated from the rheological behavior of the fluids. Pye introduced the concept of the resistance factor to quantify this effect. Burcik observed a decrease in the mobility of brine in a Berea sandstone disk that had been previously contacted with partially hydrolyzed previously contacted with partially hydrolyzed polyacrylamide. The mobility reduction persisted polyacrylamide. The mobility reduction persisted even after 100 PV of brine had been flushed through the disk. Burcik concluded that polymer molecules retained in the pore structure by adsorption or mechanical entrapment were hydrophillic and restricted the flow of water. Gogarty made an extensive experimental study of partially hydrolyzed polyacrylamide solutions in porous media and concluded that these polymer porous media and concluded that these polymer solutions reduced the permeability of the porous media. He noosed that polymer retention in natural cores occurred by mechanical entrapment and adsorption. Both mechanisms contributed to the resistance and residual or flushed resistance factors observed with polyacrylamide solutions. Other evidence of interactions between the polymer solution and the porous matrix was found. polymer solution and the porous matrix was found. Adsorption of polymer molecules on the surface of materials present in the porous matrix has been demonstrated in batch adsorption experiments. Material-balance calculations made on the streams entering and leaving porous media following step changes in concentrations show retention of polymer molecules in the porous media. polymer molecules in the porous media. A dependence of polymer retention on flow rate has been reported. Szabo devised a set of static and flow experiments in which polymer adsorption was held to a low level by using silica sand with a small surface area. Mechanical entrapment was found to be the dominant retention mechanism in short sand packs. packs. SPEJ P. 111


1996 ◽  
Vol 55 (4) ◽  
pp. 289-295 ◽  
Author(s):  
K. Hoyer ◽  
A. Gyr ◽  
A. Tsinober

1981 ◽  
Vol 103 (4) ◽  
pp. 491-496 ◽  
Author(s):  
J. T. Kuo ◽  
L. S. G. Kovasznay

A novel flow configuration was explored for the study of the behavior of drag reducing polymers. A screw pump consisting of a smooth cylinder and a concentrically placed screw was used to create a strongly three-dimensional but essentially laminar flow. In the first phase of the study, the static pressure head developed by the screw pump was measured as a function of polymer concentration (polyox 10 to 100 ppm in water). A large increase of the developed head was observed that behaved in an analogous manner to drag reduction as far as concentration and straining of the polymer solution was concerned. In the second phase of the study, a new apparatus was constructed and the additional parameter of a superimposed through flow was included and the degree of failure of the superposition principle was established. Sensitivity of the phenomenon to chemicals like HCl, HNO3, and NaOH in the polymer solution was also studied. When the effect of these chemicals on the polymer solution flow behavior was presented in terms of the pH value of the polymer solution, it showed a similar trend to those observed in drag reduction.


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