Suresh Kumar Yatirajula
Indian School of Mines, India
Suresh Kumar Yatirajula has completed his Master of Technology from Indian Institute of Technology, Madras, India by working on ‘Rheology of Aqueous CTAB/NaSal Wormlike Micelles’ and is now pursing Doctoral thesis on ‘Studies on Self Assembling Polymer (SAP) Application in Enhanced Oil Recovery Application’ at Department of Chemical Engineering from Indian School of Mines, Dhanbad, India. He is also working as an Assistant Professor at the same university currently. He has presented two papers at international conferences including 9th World Congress of Chemical Engineering, Seoul, South Korea.
Linear and nonlinear rheological responses of self-assembling polymer (SAP) systems are of great interest in chemical flooding for enhanced oil recovery (EOR) application. The motivation of these extended polymolecular assemblies with improved mechanical and thermal stability as well as tolerance to elevated salinity and hardness; superior viscoelastic properties and pronounced pseudoplastic shear thinning behavior due to network interlocking effect for EOR. The formation of these self-assemblies relies on noncovalent interactions that hold them together. The performance of two self-assembly systems derived from a xanthan gum (SAP-XG) and partially hydrolyzed polyacrylamide (SAP-HPAM). The present work is concerned with experimental results of rheological characteristic of SAP in aqueous, aqueous salt solutions and brain aqueous solutions with systematically changing experimental conditions such as polymer concentration, surfactant concentration, salt content, temperature and aging time. Rheological properties of SAP systems in both linear and nonlinear regions have been investigated by means of techniques, small amplitude oscillatory shear (SAOS) and large amplitude oscillatory shear (LAOS), respectively. Loss and storage modulus, with in linear viscoelastic range, were confirmed to be higher than the conventional base polymer. In LAOS test protocols and the associated materials measure provide a rheological figure print of the yielding behavior of a SAP (with Lissajous curves) that can be closely represented with in the domain of a Pipkin diagram defined by the amplitude and angular frequency.