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Book Correlations Among Surfactant Drag Reduction Additive Chemical Structures  Rheological Properties and Microstructures in Water and Water co solvent Systems

Download or read book Correlations Among Surfactant Drag Reduction Additive Chemical Structures Rheological Properties and Microstructures in Water and Water co solvent Systems written by Ying Zhang and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Under appropriate conditions, surfactants in water are known to self-assemble into threadlike micelles which reduce the drag of the solution in turbulent flow compared to that of the water solvent at the same flow rate. The phenomenon is called turbulent drag reduction (DR). Using surfactant DR additives (DRA) can save up to 70% pumping energy in turbulent pipe flow water circulating systems, such as district cooling/heating systems, in which a large amount of water is temperature controlled in a central station and recirculated within a district to heat/cool the buildings therein. A new approach to energy saving in district cooling systems is to replace water with 20% ethylene glycol (EG) in water as the cooling medium, which can be cooled down to -5°C (compared to 5°C for water). The coolant typically warms up to 15°C and is then returned to the central station for recooling. The temperature difference for the 20%EG/W medium is 20°C ( -5°C to 15°C), twice as much as the 10°C for water (5°C to 15°C), increasing its cooling capacity and reducing the amount of recirculating coolant and pumping energy needed by about 50%. Pumping energy could be reduced by an additional 50% if effective surfactant DRAs can be used in such mixed solvents. However, co-solvents such as EG are known to inhibit micelle formation which may decrease the effectiveness of DRAs compared to pure water systems. This study investigated and developed effective surfactant DRAs in several water/co-solvent systems at low temperatures. DR, rheological, cryogenic transmission electron microscopy (cryo-TEM) and 1H NMR experiments are being carried out to develop correlations among DR, rheological properties and micelle microstructures. In addition to the practical application in district cooling systems using EG-water mixed solvent or other co-solvent systems, the results of this study provide more fundamental understanding of the effects of solvent properties on threadlike micelle microstructure, drag reduction and system rheology, which are poorly understood now.

Book Turbulent Drag Reduction by Surfactant Additives

Download or read book Turbulent Drag Reduction by Surfactant Additives written by Feng-Chen Li and published by John Wiley & Sons. This book was released on 2012-01-10 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent drag reduction by additives has long been a hot research topic. This phenomenon is inherently associated with multifold expertise. Solutions of drag-reducing additives are usually viscoelastic fluids having complicated rheological properties. Exploring the characteristics of drag-reduced turbulent flows calls for uniquely designed experimental and numerical simulation techniques and elaborate theoretical considerations. Pertinently understanding the turbulent drag reduction mechanism necessities mastering the fundamentals of turbulence and establishing a proper relationship between turbulence and the rheological properties induced by additives. Promoting the applications of the drag reduction phenomenon requires the knowledge from different fields such as chemical engineering, mechanical engineering, municipal engineering, and so on. This book gives a thorough elucidation of the turbulence characteristics and rheological behaviors, theories, special techniques and application issues for drag-reducing flows by surfactant additives based on the state-of-the-art of scientific research results through the latest experimental studies, numerical simulations and theoretical analyses. Covers turbulent drag reduction, heat transfer reduction, complex rheology and the real-world applications of drag reduction Introduces advanced testing techniques, such as PIV, LDA, and their applications in current experiments, illustrated with multiple diagrams and equations Real-world examples of the topic’s increasingly important industrial applications enable readers to implement cost- and energy-saving measures Explains the tools before presenting the research results, to give readers coverage of the subject from both theoretical and experimental viewpoints Consolidates interdisciplinary information on turbulent drag reduction by additives Turbulent Drag Reduction by Surfactant Additives is geared for researchers, graduate students, and engineers in the fields of Fluid Mechanics, Mechanical Engineering, Turbulence, Chemical Engineering, Municipal Engineering. Researchers and practitioners involved in the fields of Flow Control, Chemistry, Computational Fluid Dynamics, Experimental Fluid Dynamics, and Rheology will also find this book to be a much-needed reference on the topic.

Book Proceedings of the Fifth International Conference in Ocean Engineering  ICOE2019

Download or read book Proceedings of the Fifth International Conference in Ocean Engineering ICOE2019 written by Vallam Sundar and published by Springer Nature. This book was released on 2020-11-08 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises the proceedings of the Fifth International Conference in Ocean Engineering (ICOE2019) focusing on emerging opportunities and challenges in the field of ocean engineering and offshore structures. Some of the themes covered in this volume are offshore structures and deepwater technology, ocean optics & acoustics, ocean renewable energy, marine spatial planning, climate change impacts & disaster risk reduction, etc. The essays are written by leading international experts, making it a valuable resource for researchers and practicing engineers alike.

Book Studies on the Nanostructure  Rheology and Drag Reduction Characteristics of Drag Reducing Cationic Surfactant Solutions

Download or read book Studies on the Nanostructure Rheology and Drag Reduction Characteristics of Drag Reducing Cationic Surfactant Solutions written by Wu Ge and published by . This book was released on 2008 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: At concentrations above CMC (critical micellization concentration) or temperatures above CMT (critical micellization temperature) surfactant molecules dissolved in aqueous solution self-assemble into colloidal aggregates such as micelles or vesicles. These colloidal aggregates vary in shape and size depending on a number of system conditions such as surfactant molecular structure, surfactant concentration, salt concentration, temperature, etc. Among the variety of micellar structures in solution, wormlike micelles resembling the long chain molecules of high polymers may reduce friction energy loss in turbulent flow by up to 90% at relatively low surfactant concentrations under appropriate flow and temperature conditions. This phenomenon is termed drag reduction (by surfactant additives) and it has significant potential impacts on fluid transport and on the environment. Among surfactant drag reducing additives, cationic surfactants with organic counterions have received the most attention in the past two decades mainly because of their excellent drag reducing ability, broad availability, low concentration requirements and general insensitivity to ionic metal impurities. Typical cationic surfactants studied for drag reduction are quaternary ammonium salts with one long alkyl chain (carbon number from 14 to 22) and methyl or hydroxyethyl groups in the other positions. They are, however, mildly toxic with poor biodegradability, so there is a need to develop more environmentally friendly surfactant drag reducing additives. Other types of surfactants such as anionics, zwitterionics and nonionics have also been studied. To obtain desired drag reducing properties, previous research has been focused on utilizing synergistic effects that may arise when two surfactant species are mixed. Mixed surfactant systems studied for drag reduction included cationic surfactants of mixed alkyl chain lengths, cationic/anionic, nonionic/nonionic, nonionic/anionic and zwitterionic/anionic surfactant mixtures in aqueous solutions and in water/co-solvent systems. Organic counterions added to dilute cationic surfactant aqueous solutions are effective in inducing and stabilizing wormlike micelle formation at relatively low counterion to surfactant molar ratios, thereby promoting their drag reducing effectiveness. The interactions of the cationic surfactant and organic counterion can be enhanced by tuning either or both of them, structurally and/or by concentration and molar ratio, to tailor-make highly efficient drag reducing systems suitable for different applications. Understanding the important role of organic counterions in the dynamics of the formation of cationic surfactant wormlike micelles and their networks is important. In this work, investigations have been conducted in how changes in the organic counterion chemical structure of a series of p-halobenzoates and counterion to surfactant ratio affect zeta potential, nanostructure, drag reduction and rheological properties. Also, certain mixed aromatic counterion systems were studied which showed excellent synergistic effects on promoting wormlike micellar branched networks and enhancing drag reducing effectiveness. In this work, an enclosed rotating disk apparatus was designed and constructed for screening novel surfactant species synthesized in chemistry laboratories. After correlating its drag reducing results with those obtained through the conventional pipe flow test system, this small scale apparatus is capable of testing materials for drag reduction effectiveness independently. A long range goal of this research is to develop effective low concentration surfactant systems with good drag reduction effectiveness. Guided by the correlations and understandings obtained in the past research, in this work, a number of new surfactants or counterions were selected or synthesized for exploratory drag reduction tests.

Book Handbook of Surface and Colloid Chemistry

Download or read book Handbook of Surface and Colloid Chemistry written by K. S. Birdi and published by CRC Press. This book was released on 2015-06-25 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of the Handbook of Surface and Colloid Chemistry informs you of significant recent developments in the field. It highlights new applications and provides revised insight on surface and colloid chemistry's growing role in industrial innovations. The contributors to each chapter are internationally recognized experts. Several chapter

Book Polymer Physics

Download or read book Polymer Physics written by Leszek A. Utracki and published by John Wiley & Sons. This book was released on 2011-02-14 with total page 677 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive review of the state-of-the-art advanced research in the field, Polymer Physics explores the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Featuring contributions from renowned experts, the book covers the basics of important areas in polymer physics while projecting into the future, making it a valuable resource for students and chemists, chemical engineers, materials scientists, and polymer scientists as well as professionals in related industries.

Book Investigation of Relationships Among Microstructure  Rheology  Drag Reduction and Heat Transfer of Drag Reducing Surfactant Solutions

Download or read book Investigation of Relationships Among Microstructure Rheology Drag Reduction and Heat Transfer of Drag Reducing Surfactant Solutions written by Yunying Qi and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Drag reducing (DR) surfactant solutions can reduce pumping energy requirements in district heating and cooling (DHC) systems by 30-60%. To enhance the heat transfer ability of DR surfactant solutions, three methods were investigated. Fluted tube-in-tube heat exchangers and installing destructive devices at heat exchanger entrances were found to be very effective with moderate pressure drop penalties. The former is good for new DHC systems while the latter is ideal for existing DHC systems. Ultrasonic energy break up surfactant microstructures and enhance their heat transfer ability was effective for viscoelastic drag reducing surfactant solutions. The destructive devices and ultrasonic energy temporarily destroy the surfactant microstructure which enhances heat transfer. The microstructure recovers quickly and the solution regains its DR ability downstream of the exchanger. Unsaturated hydrocarbon chains with cis and trans configurations with different counterion/surfactant ratios influence the effective DR temperature range of cationic surfactant solutions, their shear degradation, their rheological behavior and their microstructures. Shearing effects on the microstructures of different DR surfactant solutions were studied using SANS. Surfactant microstructures aligned along the flow direction under shear. However, the critical shear rate for the initiation of alignment depends on surfactant microstructure. Differences and their relation to rheological properties and DR abilities are discussed. Shear induced structures (SIS) are accompanied by first normal stress difference (N1). Non-viscoelastic DR systems do not show SIS and N1. Threadlike micelle structures appear to be present in all DR surfactant solutions under shear, however. While some DR surfactant solutions have low extensional/shear viscosity ratios at extensional rates

Book Dissertation Abstracts International

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2005 with total page 918 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Effect of Chemical Structures of Cationic Surfactants Or Counterions on Solution Drag Reduction Effectiveness  Rheology and Micellar Microstructure

Download or read book The Effect of Chemical Structures of Cationic Surfactants Or Counterions on Solution Drag Reduction Effectiveness Rheology and Micellar Microstructure written by Zhiqing Lin and published by . This book was released on 2000 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Turbulent Drag Reduction by Polymers  Surfactants and Their Mixtures in Pipeline Flow

Download or read book Turbulent Drag Reduction by Polymers Surfactants and Their Mixtures in Pipeline Flow written by Ali Asghar Mohsenipour and published by . This book was released on 2011 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lthough extensive research work has been carried out on the drag reduction behavior of polymers and surfactants alone, little progress has been made on the synergistic effects of combined polymers and surfactants. A number of studies have demonstrated that certain types of polymers and surfactants interact with each other to form surfactant-polymer complexes. The formation of such complexes can cause changes in the solution properties and may result in better drag reduction characteristics as compared with pure additives. A series of drag-reducing surfactants and polymers were screened for the synergistic studies. The following two widely used polymeric drag reducing agents (DRA) were chosen: a copolymer of acrylamide and sodium acrylate (referred to as PAM) and polyethylene oxide (PEO). Among the different types of surfactants screened, a cationic surfactant octadecyltrimethylammonium chloride (OTAC) and an anionic surfactant Sodium dodecyl sulfate (SDS) were selected for the synergistic study. In the case of the cationic surfactant OTAC, sodium salicylate (NaSal) was used as a counterion. No counterion was used with anionic surfactant SDS. The physical properties such as viscosity, surface tension and electrical conductivity were measured in order to detect any interaction between the polymer and the surfactant. The drag reduction (DR) ability of both pure and mixed additives was investigated in a pipeline flow loop. The effects of different parameters such as additive concentration, type of water (deionized (DI) or tap), temperature, tube diameter, and mechanical degradation were investigated. The addition of OTAC to PAM solution has a significant effect on the properties of the system. The critical micelle concentration (CMC) of the mixed surfactant-polymer system is found to be different from that of the surfactant alone. The anionic PAM chains collapse upon the addition of cationic OTAC and a substantial decrease in the viscosity occurs. The pipeline flow behaviour of PAM/OTAC mixtures is found to be consistent with the bench scale results. The drag reduction ability of PAM is reduced upon the addition of OTAC. At low concentrations of PAM, the effect of OTAC on the drag reduction behavior is more pronounced. The drag reduction behavior of polymer solutions is strongly influenced by the nature of water (de-ionized or tap). The addition of OTAC to PEO solution exhibited a week interaction based on the viscosity and surface tension measurements. However, the pipeline results showed a considerable synergistic effect, that is, the mixed system gave a significantly higher drag reduction (lower friction factors) as compared with the pure additives (pure polymer or pure surfactant). The synergistic effect in the mixed system was stronger at low polymer concentrations and high surfactant concentrations. Also the resistance against mechanical degradation of the additive was improved upon the addition of OTAC to PEO. The mixed PEO/SDS system exhibited a strong interaction between the polymers (PEO) and the surfactant (SDS), Using electrical conductivity and surface tension measurements, the critical aggregation concentration (CAC) and the polymer saturation point (PSP) were determined. As the PEO concentration is increased, the CAC decreases and the PSP increase. The addition of SDS to the PEO solution exhibits a remarkable increase in the relative viscosity compared to the pure PEO solution. This increase is attributed to the changes in the hydrodynamic radius of the polymer coil. The pipeline flow exhibited a considerable increase in DR for the mixed system as compared to the pure PEO solution. The addition of surfactant always improves the extent of DR up to the PSP. Also the mixed PEO/ SDS system shows better resistance against shear degradation of the additive.

Book Drag Reduction of Turbulent Flows by Additives

Download or read book Drag Reduction of Turbulent Flows by Additives written by A. Gyr and published by Springer. This book was released on 2010-10-28 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drag Reduction of Turbulent Flows by Additives is the first treatment of the subject in book form. The treatment is extremely broad, ranging from physicochemical to hydromechanical aspects. The book shows how fibres, polymer molecules or surfactants at very dilute concentrations can reduce the drag of turbulent flow, leading to energy savings. The dilute solutions are considered in terms of the physical chemistry and rheology, and the properties of turbulent flows are presented in sufficient detail to explain the various interaction mechanisms. Audience: Those active in fundamental research on turbulence and those seeking to apply the effects described. Fluid mechanical engineers, rheologists, those interested in energy saving methods, or in any other application in which the flow rate in turbulent flow should be increased.

Book Investigations on Drag Reduction by Interactions Between Polymer and Surfactant and Polymer and Polymer

Download or read book Investigations on Drag Reduction by Interactions Between Polymer and Surfactant and Polymer and Polymer written by Jia Yang and published by . This book was released on 2015 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: A large amount of studies have been carried out on pipeline flow with several kinds of drag reducing agents, especially polymers and surfactants. Drag reducing agents, by definition, are additives which help suppress or eliminate turbulence in a pipeline. The mechanism and methodology of polymer only or surfactant only as drag reducing additives have been fully discovered. Whether mixed drag reducers such as polymer-surfactant or polymer-polymer systems would be effective is still not clear. In our study, polymer-surfactant and polymer-polymer mixed additives are used in order to explore the synergistic effects and interactions in pipeline flow loops. The experimental work was divided into two sections: bench-scale experiments and pilot-scale experiments. In bench-scale experiments, the properties of prepared fluids such as, surface tension, conductivity and shear viscosity were measured. Several comparison methods and calculations were applied to give better understandings of the properties resulting from mixing of polymer with surfactant and polymer with polymer. After analysis of the properties, several combinations of concentrations were selected and solutions were prepared in the main tank of pilot plant and pumped into the pipeline set-up to test the pipeline flow behaviors. Turbulence structure/Reynolds number, pipe diameter, polymer-surfactant concentration were all considered as influencing factors. Critical micelle concentration, critical aggregation concentration, polymer saturation point, the onset of drag reduction, and the interactions between the mixed additives were discussed. A comparison between pipeline results and the predictions of Blasius Equation or Dodge-Metzner Equation were also discussed.. For polymer-surfactant studies, a commonly used polymer additive - carboxylmethylcellulose (referred to as CMC which is anionic) was selected as the drag reducing agent. The performance of this polymer was investigated in the presence of six surfactants respectively - Alcohol ethoxylate (referred to as Alfonic 1412-9 and Alfonic 1412-3 which are nonionic), Aromox DMC (nonionic surfactant), Stepanol WA-100 and Stepwet DF-95 (which mainly consist sodium lauryl sulfates, anionic surfactant) and Amphosol (which is zwitterionic).The experiments were first conducted with pure CMC solution with different concentrations (100ppm, 500ppm, 700ppm and 1000ppm) as a standard. The 500ppm CMC solution was selected as the best polymer concentration with highest drag reduction efficiency. For polymer-surfactant combinations, CMC-Alfonic 1412-9, CMC-Alfonic1412-3, CMC-Stepanol and CMC-Stepwet systems were found to have significant interactions. High surfactant concentration resulted in reduction in %DR. The addition of Aromox increased the drag reduction ability and onset point when concentration was higher than the polymer saturation points. Also, both hydrophobic and electrostatic interactions were thought to have an effect on critical micelle concentration, which led to the fluctuations in the %DR. For polymer-polymer studies, PAM-PEO system at two different polymer concentrations were investigated. Overall, Pure PAM solution had much higher drag reduction ability than pure PEO solutions. Mixing them together, strong interactions occurred when PEO fraction was high (over 50%) which affected %DR and shear viscosity substantially. Power-law constants n and k were also taken into account and found to exhibit opposite trends with the increase of PEO fraction.

Book Interactions Between Drag Reducing Polymers and Surfactants

Download or read book Interactions Between Drag Reducing Polymers and Surfactants written by Ketan Prajapati and published by . This book was released on 2009 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drag reduction in turbulent pipe flow using polymeric and surfactant additives is well known. Although extensive research work has been carried out on the drag reduction behavior of polymers and surfactants in isolation, little progress has been made on the synergistic effects of combined polymers and surfactants. In this work the interactions between drag-reducing polymers and surfactants were studied. The drag-reducing polymers studied were nonionic polyethylene oxide (referred to as PEO) and anionic copolymer of acrylamide and sodium acrylate (referred to as CPAM). The drag-reducing surfactants studied were nonionic ethoxylated alcohol - Alfonic 1412-7 (referred to as EA), cationic surfactant - Octadecyltrimethylammonium chloride in pure powder form (referred to as OTAC-p) and commercial grade cationic surfactant - Octadecyltrimethylammonium chloride in isopropanol solvent - Arquad 18-50 (referred to as OTAC-s). The interactions between polymers and surfactant were reflected in the measurements of the physical properties such as electrical conductivity, surface tension, viscosity and turbidity. The critical micelle concentration (cmc) of the mixed polymer / surfactant system was found to be different from that of the surfactant alone. The viscosity of a polymer solution was significantly affected by the addition of surfactant. Weak interactions were observed for the mixed systems of nonionic polymer - nonionic surfactant and anionic polymer - nonionic surfactant. Due to the wrapping of polymer chains around the developing micelles, a minimum in the viscosity is observed in these two cases. In the case of nonionic polymer / cationic surfactant system, the change in the viscosity was found to depend on the polymer concentration (C) and the critical entanglement concentration (C*). When the polymer concentration (C) was less than C* (C C*), the plot of the viscosity versus surfactant concentration exhibited a minimum. When C C*, a maximum in the viscosity versus surfactant concentration plot was observed. The interactions between nonionic polymer and cationic surfactant were observed to increase with the increase in temperature. A large drop in the viscosity occurred in the case of anionic-polymer / cationic-surfactant system when surfactant was added to the polymer solution. The observed changes in the viscosity are explained in terms of the changes in the extension of polymeric chains resulting from polymer-surfactant interactions. The anionic CPAM chains collapsed upon the addition of cationic OTAC-p, due to charge neutralization. The presence of counterion sodium salicylate (NaSal) stabilized the cationic surfactant monomers in the solution, resulting in micelle formation at a surfactant concentration well below the concentration where complete charge neutralization of anionic polymer occurred. Preliminary results are reported on the pipeline drag reduction behavior of mixed polymer-surfactant system. The results obtained using combinations of CPAM / OTAC-p in pipeline flow are found to be in harmony with the interaction study. Due to the shrinkage of CPAM chains upon the addition of OTAC-p, the drag reducing ability of CPAM is compromised.

Book New Correlation for Predicting the Best Surfactant and Co solvent Structures to Evaluate for Chemical EOR

Download or read book New Correlation for Predicting the Best Surfactant and Co solvent Structures to Evaluate for Chemical EOR written by Leonard Yujya Chang and published by . This book was released on 2014 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this study was the development of an improved correlation that more accurately quantifies the relationships between optimum salinity, optimum solubilization ratios, chemical formulation variables such as surfactant and co-solvent structures, and the EACN. Entrained in this study are improved correlations for co-solvent partition coefficients and correlations for the optimum salinity and solubilization ratio with EACN. Several trends in the oil-water partition coefficient were observed with the alcohol type (IBA and phenol), the number of ethylene oxide groups in the co-solvent, the EACN of the oil, temperature, and salinity. New EACN measurements were made using optimized formulations containing various combinations of primary surfactants, co-surfactants, co-solvents and alkali. The new EACN measurements ranged from 11.3 to 21.1. These new data significantly expand the total number of reliable EACN values available to understand and correlate chemical EOR formulation results. An improved correlation that more accurately quantifies the relationship between surfactant structure, co-solvents, oil, temperature, and optimum salinity was developed using a new and much larger high quality formulation dataset now available from studies done in recent years in the Center for Petroleum and Geosystems Engineering at the University of Texas at Austin. The correlation is useful for understanding the now very large number of microemulsion phase behavior experiments as well as the uncertainties associated with these data, and for suggesting new chemical structures to develop and test.

Book Prediction of Microemulsion Phase Behavior from Surfactant and Co solvent Structures

Download or read book Prediction of Microemulsion Phase Behavior from Surfactant and Co solvent Structures written by Leonard Yujya Chang and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Structure-property models were developed to predict the optimum salinity, optimum solubilization ratio, and the aqueous stability limit from the molecular structures of surfactants and co-solvents used for enhanced oil recovery. The models are sufficiently accurate to provide a useful guide to experimental testing programs for the development of chemical formulations for enhanced oil recovery and other similar applications requiring low interfacial tension. This is the first time a structure-property model has been developed to predict the optimum solubilization ratio. The solubilization ratio can be used in the Huh equation to predict the interfacial tension, which is the most important property in enhanced oil recovery applications. The UTCEOR Database was constructed and used to develop the models. The database is a collection of highest-quality experimental chemical EOR data conducted at The University of Texas at Austin from 2005 to 2018. It contains several thousand phase behavior experiments using 34 unique crude oils, 294 unique surfactants, and 70 unique co-solvents. The structures of the surfactants and co-solvents were characterized and include variations in the type of hydrophobe (carbon number, degree of branching, polydispersity, and aromaticity), number of alkoxylate groups (propylene oxide and ethylene oxide), and the type of head group. The model focuses on blends of anionic surfactants and nonionic co-solvents. Both the optimum salinity and the optimum solubilization ratio were modeled as a function of monovalent and divalent cations in the brines. The oils were characterized using their equivalent alkane carbon number. The models include the effect of soaps generated from the neutralization of acidic crude oils. Previous models for optimum salinity have not included the effects of divalent cations, soap, and co-solvents among other limitations. Most importantly, the new model can be used to predict interfacial tension as well as optimum salinity whereas previous models were used to predict only optimum salinity. In this research, the structure-concentration and structure-property effect of co-solvents were modeled separately, whereas previous models convoluted both effects and were not predictive. New measurements were made and combined with literature data to develop improved correlations for the oil-water partition coefficient and the interface-water partition coefficient of co-solvents. These correlations were used with pseudophase theory to more accurately model the structure-concentration effect. A structure-property model was developed for the aqueous stability that predicts the coacervation of chemical formulations. The interactions between surfactant hydrophobes and the PO groups were modeled because they influence the stability of micelles. The effects of co-solvent, polymer, and divalent cations were included for the first time. The structure-property models can be used to predict formulations for a given oil, brine and temperature that are likely to achieve ultra-low IFT with aqueous stability at optimum salinity and thus greatly accelerate the process of finding the best formulations to test for chemical EOR

Book Structure performance Relationships in Surfactants

Download or read book Structure performance Relationships in Surfactants written by Milton J. Rosen and published by . This book was released on 1984 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Solvent Properties of Surfactant Solutions

Download or read book Solvent Properties of Surfactant Solutions written by Kōzō Shinoda and published by Hodder Education. This book was released on 1967 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: