Showing papers by "Mingwei Zhao published in 2022"
TL;DR: In this article , a new class of nano-surfactants, called amphiphilic carbon dots (C12-CDs), were synthesized under mild reaction conditions, and they exhibit higher surface activity than conventional surfactants (APG12 and SDBS).
15 citations
TL;DR: In this article , a pre-developed silica nanoparticle-reinforced CO2-sensitive fracturing fluid system was studied, and the imbibition factors of the gel breaking fluid were studied.
7 citations
TL;DR: In this article, a novel CO2-induced clean fracturing fluid (SDS-TMTAD-CO2) is formulated with simulated formation water (23,003 ǫmg l−1) after optimization experiments according to the proposed parameters.
7 citations
TL;DR: In this article , a C18-tailed zwitterionic surfactant supramolecular hydrogel is constructed with OHSB and NaSal and the microstructure of the system was analyzed by 1 H NMR, rheological property, cryo-SEM, and DLS.
5 citations
TL;DR: In this article , the effect of hydrophobic interaction and electrostatic interaction on the structure of worm-like micelles was studied, and it was shown that increasing the hydrocarbon chain length of zwitterionic surfactant and the addition of cetyl trimethyl ammonium chloride (CTAC) can increase the viscoelasticity and zero-shear viscosity of the system.
3 citations
TL;DR: In this article , the effect of clean fracturing fluid and its gel breaking liquid on the spontaneous imbibition was investigated and the results indicated that, with the reduction of concentration and increases of temperature and salinity, the imputation recovery can be improved.
Abstract: In the late stage of unconventional oil and gas fracturing development, the production decreases rapidly, and spontaneous imbibition can effectively improve oil and gas recovery. Spontaneous imbibition mostly relies on external imbibition agents, and there are few studies on the direct use of clean fracturing fluid and the effect of its spontaneous imbibition. This work systematically studies the imbibition performance of clean fracturing fluid and its gel breaking liquid. To find the key factors for the imbibition recovery, the effects of concentration, temperature, and salinity were studied. The results indicate that, with the reduction of concentration and increases of temperature and salinity, the imbibition recovery can be improved. To clarify the imbibition mechanism, the performance, including spontaneous imbibition, interfacial tension, and wettability, of clean fracturing fluid and its gel breaking liquid was evaluated and compared. The results show that the gel breaking liquid contains some surfactant molecules, showing good wettability alteration, emulsification, and interfacial activity. The spontaneous imbibition recovery of the gel breaking liquid is the highest compared with that of fracturing fluid and simulated water. Finally, the T2 spectrum and 1H NMR image of the core before and after imbibition are obtained, revealing the micro imbibition mechanism of the gel breaking liquid. The gel breaking liquid can enter the small pores through the capillary force, discharge the crude oil into the large pores through the small pores, finally gather and discharge. Therefore, the gel breaking liquid has the characteristics of little damage and low viscosity, making it easy to enter micropores and help to improve oil production through spontaneous imbibition. It can give new ideas and methods for improving production capacity in the later stage of fracturing development.
3 citations
TL;DR: In this article , seven heptadecafluorodecyl acrylate/styrene (HFDA/STY) copolymers were synthesized, their solubility and thickening properties in SC-CO2 were evaluated.
3 citations
TL;DR: In this article , the effects of nanoparticle surfactancy on surface rheology, fluidity and shear force field around bubbles were quantitatively analyzed, and it was found that the adsorption of nanoparticles on the bubble surface gives rise to surface solidification, the flow velocity close to surface decreased by 76%, meanwhile the shear stress loaded on bubble surface increases sharply.
2 citations
2 citations
TL;DR: In this article , a novel anionic surfactant 1,2-decanediol dihydroxypropyl sulfonates (D-diHS) was designed from the perspective of oil-solid interfacial interaction control, exhibiting great application potential in efficient residual oil development.
2 citations
TL;DR: In this paper , the dissolution and thickening behavior of polysiloxane-type polymer is further studied by molecular dynamics simulation, and the roles of functional groups of thickeners in the dissolution process are discussed.
TL;DR: In this article , a novel anionic surfactant sodium dihydroxymethyl dodecyl sulfate (SDDS) was synthesized by a simple one-step grafting of hydroxyl groups onto SDS, which could achieve enhanced adsorption to the oil-wet rock surface and the exposed head groups exhibited improved hydrophilicity.
TL;DR: In this paper , deep eutectic solvents (DESs) were developed as the enhancers to intensify rheological characteristics and spontaneous imbibition performance of CFFs.
TL;DR: In this paper , a novel type of superhydrophobic nanoparticle (SHNP) was modified by fluorinated long chains, and a stable nanofluid was successfully prepared by compounding surfactant.
TL;DR: In this paper , a 1D continuous pore-throat visualization model (PTVM), a 2-D heterogeneous PTVM, and a 3-dimensional heterogeneous core model were constructed and used to investigate porescale migration, retention and controlling mechanism of EGPs profile control.
TL;DR: In this article , an anhydrous CO2 fracturing fluid system was constructed with the compositions of 7 wt% polydimethylsiloxane (100 cs), 5 t% ethanol, and 88 tt% liquid CO2.