Midstream: Transportation, separation, water management and storage

Use Cases 

What are the effects of elastic properties of a crude oil-water interface stabilized with crude stabilizers on demulsification under desalting conditions?

Reference: PetroPhase 2021 Peter Perez, Jenee’ Zaragoza, Nimeshkumar Patel, Michael Dion. SUEZ - Water Technologies & Solutions. Tomball Technology & Innovation Center, Tomball, Texas.

Despite their widespread use, the behavior of CS (crude stabilizers) is not yet fully understood. In this work, the relationship between the elasticity of a crude oil–water interface stabilized with CS and demulsification efficiency is investigated under desalting conditions. Six different CS (noted A to F) and one demulsifier (EB: alkylphenol resin ethoxylate) have been used. The first series of experiments allowed us to probe the efficiency of demulsification using a crude oil treated with EB in the presence or absence of CS under desalting conditions. Then, interfacial rheology measurements on crude oil-water interfaces stabilized with CS have been performed with an automatic drop tensiometer (TRACKERTM). The experimental results showed that both antagonistic and synergetic interactions between EB and CS are possible depending on the dosage of EB and CS.  Moreover, a low viscous modulus was found to be correlated with better demulsification.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: crude oil-water interface, crude stabilizers, demulsifiers, desalting conditions, interfacial rheology.

What are the effects of dissolved state paraffins on oil/water interfacial properties and the

stability of water-in-oil emulsions ? 

Reference: Sun, G., Zhang, H., Liu, D., You, J., Yang, F., Li, C., & Yao, B. (2019). Impact of the composition and content of dissolved-state paraffins in model oil on the aggregation state of asphaltenes and the stability of water-in-model oil emulsion. Energy & Fuels, 33(12), 12191-12201.

In this paper, the authors probe the effect of dissolved-state paraffins with different carbon number distributions (CNDs) on model oil/water interfacial characteristics and on the stability of water-in-model oil emulsions. Using an automatic drop tensiometer (TRACKER™), surface tension and interfacial rheology measurements have been performed on model oil –brine water interface. Different model oil formulations have been tested: asphaltenes with paraffin A or B at different concentrations. The results show that increasing the paraffin content leads to the rising of surface tension. In terms of interfacial rheology, paraffin increased the interfacial dilatational modulus. These observations have been attributed to the flocculation of asphaltenes into larger aggregates when the paraffin content is increased (larger diffusion rate and enhanced structural strength of interfacial films) which also results in an enhanced stability of the oil-in-water emulsion.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: Interfacial tension, interfacial rheology, asphaltenes, dissolved-state-paraffins, oil, emulsion, stability.

How do resins and asphaltenes interact and impact water/oil interfacial properties

and emulsion stability?  

Reference: Liu, D., Li, C., Yang, F., Sun, G., You, J., & Cui, K. (2019). Synergetic effect of resins and asphaltenes on water/oil interfacial properties and emulsion stability. Fuel, 252, 581-588.

During crude oil production, oil/water emulsions are usually generated due to the presence of natural surface-active components in the oil phase . In this paper, the authors focus on asphaltenes and resins and the impact of their interaction on oil/water interfacial properties and emulsion stability. First surface tension and interfacial rheology measurements at an oil/water interface were performed using an automatic drop tensiometer (TRACKER™). A synergetic effect of asphaltenes and resins is observed through the comparison of the dynamic surface pressure of the binary system with that of the single system: the addition of resins enhances the interfacial affinity of asphaltenes at the beginning of the adsorption. However, the addition of resins reduces the dilational modulus, weakening the structural strength of interfacial layers. Experiments at the scale of the emulsion showed that the addition of resins increases the stability of emulsion at initial time but the emulsion stability is deteriorated when the resins are excessive.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: asphaltenes, resins, oil/water interface, emulsion, synergy, interfacial tension, stability interfacial rheology.

What is the impact of the aggregation state of asphaltenes on the structure related properties of the model oil/brine water interface? 

Reference: You, J., Li, C., Liu, D., Yang, F., & Sun, G. (2019). Influence of the aggregation state of asphaltenes on structural properties of the model oil/brine interface. Energy & Fuels, 33(4), 2994-3002.

Asphaltenes play a major role on the stability of heavy oil emulsions. Under this background, this study focuses  on the effect of the aggregation state of asphaltenes  on the interfacial properties of model oil/ brine water interface. Thanks to an automatic drop tensiometer (TRACKERTM),  surface tension and interfacial rheology measurements have been performed.  The collected experimental data showed that the higher level of aggregation changes the adsorption kinetics of the asphaltenes at the interface, causing a slower descending rate of the diffusion coefficient. Moreover, the interfacial viscoelastic experiment demonstrates that the interfacial dilatational modulus is increased with the addition of asphaltenes, but the rising trend becomes gentle at the concentrations above 100 ppm, indicating that the cross-linked structure in the interfacial film changes slightly with the addition of asphaltenes.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: asphaltenes, state of aggregation, model oil, surface tension, interfacial rheology, emulsion.

How do wax crystals form in

water-in-crude-oil emulsion?  

Reference: Li, Y., Li, C., Sun, G., Chen, X., Liu, D., Yang, F., ... & Zhao, Y. (2020). Characterization of the Precipitation Modes of Paraffin Wax in Water-in-Model-Oil Emulsions. Energy & Fuels, 34(12), 16014-16022.

In this study, the authors investigate the precipitation modes of paraffin wax in water-in-model-oil emulsions. First, water droplets were found to increase the wax precipitation temperature (WPT). Further, using an automatic drop tensiometer (TRACKERTM), surface tension and interfacial rheology measurements were performed above and below the WPT and showed that wax crystals did adsorb at the interface and forced the interface to solidify, causing the interface to wrinkle when shrinking.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: water-in-crude-oil emulsion, paraffin wax, wax precipitation temperature, surface tension, interfacial rheology.

How do the interactions of Dodecylbenzenesulfonic Acid (DBSA) and asphaltenes impact the interfacial properties

of model oil emulsion? 

Reference: Liu, D., Li, C., Li, L., Dong, L., Chen, X., Yang, F., & Sun, G. (2020). Effect of the Interactions between Asphaltenes and Amphiphilic Dodecylbenzenesulfonic Acid on the Stability and Interfacial Properties of Model Oil Emulsions. Energy & Fuels, 34(6), 6951-6961.

The interactive effects between DBSA and asphaltenes on the interfacial property  of model oil emulsion is investigated in this paper. The adsorption process of DBSA and asphaltenes is investigated by measuring the dynamic interfacial tension using an automatic drop tensiometer (TRACKERTM). The DBSA and asphaltenes are found to form a composite interfacial layer with a competitive adsorption mechanism. The viscoelasticity of the layer is explored by measuring the dilational modulus. The modulus declines after adding the DBSA, proving that the strength of the layer is decreased. Meanwhile, the compressibility of the layer is proved to be stronger by adding DBSA.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: asphaltenes, dodecylbenzenesulfonic acid, emulsion, interfacial properties, interfacial rheology, crumpling.

What are the effects of the polarities of asphaltene subfractions on emulsion stability

and interfacial properties?  

Reference: Liu, D., Li, C., Zhang, X., Yang, F., Sun, G., Yao, B., & Zhang, H. (2020). Polarity effects of asphaltene subfractions on the stability and interfacial properties of water-in-model oil emulsions. Fuel, 269, 117450.

In this paper, the authors investigate the effect of polarities of asphaltene subfractions on interfacial properties and water-in-oil model emulsions. Using asphaltene subfractions with different polarities and an automatic drop tensiometer (TRACKERTM), surface tension and interfacial rheology measurements showed that the initial value of interfacial tension decreases with weakening subfraction polarity while, in the long adsorption process, DIFT decreases more with decreasing polarity of the asphaltene subfractions at the same adsorption time, indicating a rising adsorption rate. In terms of interfacial rheology, the dilational modulus was found to decrease monotonously with decreasing subfraction polarity.

TECLIS product: TRACKER-H™ (up to 200°/200bar)

Key words: asphaltene, polarity, oil-water interface, water-in-model oil emulsion, surface tension ,interfacial rheology.