Effects of Native and Non-Native Resins on Asphaltene Deposition and the Change of Surface Topography at Different Pressures: An Experimental Investigation

Abstract

Asphaltene deposition during oil production and transportation causes extensive damage to reservoirs and wellhead equipment. In this study, the effects of native and non-native resins as well as their mixtures on the asphaltene deposition process are investigated. A novel pressure, volume, and temperature (PVT) visual cell is used to check the effect of resin on asphaltene deposition at different pressures and reservoir temperatures. Two Iranian crude oil samples with different potential of asphaltene deposition (low and high) were used in these tests. During depressurizing in the presence of native and non-native resins, the amount of asphaltene deposited was measured. To monitor any changes in surface topography, the atomic force microscopy (AFM) technique was used in this study. The results show that the amount of asphaltene deposited decreases as the amount of resin increases; however, less asphaltene is deposited when the resin mixture is used than when the native resin is used. At high ratios of resin to asphaltene, the stability of asphaltene is higher, but as the pressure increases, the stability of the asphaltene decreases more than expected. The surface property changes indicate that, in the presence of the resin mixture, the surfaces are less affected.

Surface and Interface Characterization of Asphaltenic Fractions Obtained with Different Alkanes: A Study by Atomic Force Microscopy and Pendant Drop Tensiometry

“…As observed by Soorghali et al, the presence of resins changes the way asphaltenes affect the surface, generally leaving the film more homogeneous and less rough. As observed in the characterization, the AP fractions may present a greater amount of coprecipitated resins that are responsible for the variations between the topographies of AH and AP.…”

“…Asphaltenes are formed by aromatic and naphthenic nuclei, aliphatic chains, and heteroatoms, such as oxygen, nitrogen, or sulfur, presenting the highest polarity and molecular weight among petroleum components. Usually asphaltenes are defined as the fraction insoluble in paraffinic hydrocarbons, such as n -heptane, and soluble in aromatics, such as toluene. − …”

Preparation and evaluation of double‐hydrophilic diblock copolymer as viscosity reducers for heavy oil

“…Outputs of heavy oil often decreased sharply with the increase of oil viscosity, and stable yields would become hard works when faced with heavy oil with high viscosities. In the last two decades, many studies have been carried on focusing on the structures and compositions of heavy oil 5–12 . It was found that the high content of asphaltenes and resins in heavy oil is the top reason that boosts the growth in viscosity.…”

Deposition and Removal Studies of Asphaltene from the Glass Surface

“…In a similar context, Labrador et al 22 also conducted studies with toluene−asphaltene solutions of concentrations ranging from 200−10,000 mg/L and reported the thickness of deposited asphaltene films on glass varying in the range of 20−298 nm. In a different study with asphaltene solutions prepared in heptane−toluene mixtures, Soorghali et al 23 reported the roughness of two distinct substrates characterized by AFM to be 168 and 56.6 nm, respectively. The authors stated the difference in roughness as a result of different origins of asphaltene.…”

“…The authors stated the difference in roughness as a result of different origins of asphaltene. Both of these individual studies , suggest that asphaltene aging results in a deposition thickness of a few hundred nanometers on glass surfaces, which is also a function of asphaltene concentration.…”