Es of crude oils have been applied in this study, with the temperatures approximating these recorded in the oil wells from which the samples had been taken: East Moldabek (oil effectively 2027) using a density and viscosity equal to 0.89 g/cm3 and 138.8 cp, respectively, at 25 C. Karazhanbas (oil nicely 1913) with density values of 0.93 g/cm3 and 0.907 g/cm3 at C and 60 C, respectively, whilst the viscosity corresponds to 420 cp and 64 cp at 30 C 30 and 60 C, respectively. two.2. Procedures two.two.1. Rheological Studies The viscosities of your TPA and HPAM have been measured using a Brookfield viscometer (Spindle-0) at a stable shear price of 7.32 s-1 . The temperature inside the rheological tests varied from space temperature (24 C) to 60 C. On the other hand, an Anton Paar Rheolab QC viscometer was utilized to measure the viscosity in the effluent samples for the HPAM experiment on the 8.6 cm-length sand pack. 2.two.two. Sand Pack and Core Flooding Sand pack flooding was carried out using the support of a particular core flooding setup equipped having a Hassler core holder and piston pumps (Figure 5).Polymers 2022, 14,six ofFigure five. Hassler core holder (a) and core flooding setup (b) applied within the present study.The basic methodology of the sand-pack and core flooding tests is described inside the following steps:Vacuum the model for a minimum of 10 min; Saturate the model with brine utilizing a high-pressure piston pump; Displace brine with oil till irreducible water saturation is reached; Simulate water flooding applying one or, in some situations, extra pore volumes of brine; Simulate polymer flooding utilizing a number of pore volumes of TPA or HPAM options.The flow rates, ambient temperature, and confining pressure values utilized in the tests are outlined in Section three.two. Of value is the fact that, within this study, the injection pressure was measured only in the inlet across the injection tube, whereas the outlet with the core was open to the atmosphere. The effluent samples containing oil and brine/polymer had been collected in glass test tubes. The fluids had been separated manually by withdrawing water from the test tube working with a syringe. The mass of oil displaced from the model was measured by calculating the distinction between the masses of the test tubes with and without oil. Lastly, the oil recovery factor was calculated by dividing the mass on the displaced oil by the initial mass with the oil inside the model. 3. Results and Discussion 3.IL-2 Protein site 1. Rheological Research Figure six shows that the viscosity from the 0.25 wt. TPA remedy is reasonably stable and equal to around 26 cp at 24 C and about 14 1 cp at 60 C in brine with salinity from 200 to 300 g -1 . In contrast, the viscosity from the 0.ANGPTL3/Angiopoietin-like 3 Protein manufacturer 25 wt.PMID:24733396 HPAM solution decreases from 28.25 cp to 7.5 cp at 24 C and from 11.two cp to three.25 cp at 60 C in brine with salinity from 200 to 300 g -1 . The structures of HPAM, a polyelectrolyte, and TPA, a polyampholyte, dictate their behaviors in saline options. The HPAM chains have a tendency to coil with a rise in salinity, because the electrostatic repulsion amongst negatively charged carboxylic groups is screened by the added salts, demonstrating the polyelectrolyte effect. Additionally, the bivalent cations (Ca2+ and Mg2+ ) present in saline solution can bridge the carboxylic ions within the HPAM, proficiently shrinking the macromolecules [34]. Nevertheless, the TPA macromolecule chains tend to unfold in saline solutions due to the screening of the electrostatic attraction among negatively charged AMPS and positively charged APTAC moieties, demonstrating the antipolyele.
