The new polyamide polymer thermal stability evaluation
"For the preparation of samples in the CaCl2 - NaCl solution, besides AN132 VHM - all of the polymer in 90 days will be the viscosity decrease after aging, this is because the cation have strong charge screening ability, and can be united in wedlock with polymer on the negative."
In the next 50 years, the supply of crude oil may not be enough to meet the world's growing energy needs.Demand for oil continues to rise, and searching for the challenge of new oil fields, more and more difficult.
Extension of the existing oil supply service time of one of the methods is to improve the oil recovery factor.This ratio is usually very low, between 20-40%, while the recovery of a gas field has reached to 90%.
Ascension as a result, oil recovery (EOR) technology is becoming more and more important, and has set up a global oil field is widely used in 1.This strategy for the development of alternative energy sources and technology provides more time, so as to fill the energy gap due to oil reserves run out.
Fortunately, a lot of EOR strategy showed sustained growth in oil production 2.Because of the ocean can offer convenience for oilfield water, so water flooding method is usually the preferred solution.The water injection reservoir, keeping within the reservoir pressure gradient needed for oil flow into the production well.Because the water flow speed is faster than oil, so tend to penetrate oil layer 3.Therefore, to reduce the phenomenon can increase the flow volume of oil production Wells.In injection water in polymer to improve its viscosity, make the water flow slows down and forcing more oil into the production well, so as to improve oil recovery factor.
In the past, the oil industry not hydrolyzed polyacrylamide of using synthetic polymer for polymer water flooding.Chose them, it is due to its good chemical stability, but they are in a high degree of mineral surface adsorption, would result in a considerable loss of polymer.They are partially hydrolyzed polyacrylamide (HPAM) polymer replaced, because some of the amide group in the HPAM into carboxylic acid base, thus has higher viscosity of 4.Due to the negatively charged surface of the rock to exclude the negatively charged carboxy group, thus the adsorption effect of HPAM is lesser also.
However, at high temperatures and (or) high salinity reservoir, HPAM will be degradation, results in the decrease of viscosity, which would lower the oil recovery factor.Therefore, we need to find new thermal degradation of polymer to optimization of polymer water flooding method to improve recovery factor.
Recently, the researchers assessed the four new thermal stability of polymer under different salinity of 5.Under 80 ℃, sulphonated polyacrylamide copolymer FLOCOMB C7035, AN132 VHM, SUPERPUSHER SAV55 and heat of associating content in CaCl2 - NaCl or NaCl solution, respectively, with or without aging antioxidants for 90 days.
The brook 500 MHz nuclear magnetic resonance spectrometer of Fourier transform infrared spectrum (FTIR) and nuclear magnetic resonance (NMR) analysis shows that both in NaCl and CaCl2 - NaC as solvent, do not contain antioxidants of the viscosity of the polymer samples are significantly reduced.Heat of associating immediately began to degradation, while other polymer viscosity can maintain at least 7 days.
When there are antioxidants, all of the preparation of polymer samples in NaCl medium viscosity increases with aging.Likewise, preparation in CaCl2 - NaC AN132 VHM after 90 days aging indicated that the increase of viscosity., by contrast, in spite of antioxidants and other polymer viscosity will reduce in the CaCl2 - NaC.
References:
- Udy J, et al. The Processes 2017, 5, 34.Doi: 10.3390 / pr5030034
- Oil and Gas Authority 2017. Available at https://www.ogauthority.co.uk/media/4283/polymer-eor-industry-starter-pack-ver3.pdf
- Sheng JJ, et al. J Can Pet Technol, 2015;54:11 6-126.
- Hashmet MR, et al. J Dispers Sci Technol, 2013;35:51 0-517.
- Akbari S, et al. 2017 Polymers;Mount zalmon 0 ‑ 494.
