Effect of n-Alkane Precipitants on Aggregation Kinetics of Asphaltenes

Abstract

The effect of different n-alkane precipitants on the kinetics of asphaltene aggregation is investigated in this study. When the chain length of the n-alkane precipitant, i.e., the carbon number, is increased, both the viscosity and solubility parameter of the solution increase and, as a result, the aggregation rate is expected to decrease. However, the actual behavior of the system is more subtle, and the aggregation rate can remain constant, increase, or pass through a maximum as the carbon number, n, increases. This behavior can be explained by the polydispersity of asphaltenes and the weaker precipitating power of longer chain n-alkanes. The polidispersity of asphaltenes is successfully characterized using their solubility parameter and the model developed in our previous study (Haji-AkbariN.MasirisukP.HoepfnerM. P.FoglerH. S. Haji-Akbari, N. Masirisuk, P. Hoepfner, M. P. Fogler, H. S. Energy Fuels20132724972505), where a universal relationship between the detection time and the differences in solubility parameters was established. The solubility parameter of the precipitated asphaltenes is shown to increase with increasing the chain length of the n-alkane precipitants and is successfully used to predict the aggregation rate of asphaltenes in blends of up to five different n-alkane precipitants.

Combined Investigations of Fluid Phase Equilibria and Fluid–Solid Phase Equilibria in Complex CO2–Crude Oil Systems under High Pressure

“…In this experiment, the compression rate was fixed to 0.3 MPa/min since it represents the best compromise between the lower rates that reduce kinetic effects but increase the noise caused by the pump in pressure rate regulation, and the higher rates that reduce noise but reduce the time for vapor dissolved in the oil during the compression. Of course, whether it is for the determination of the LAIP or the UAIP, asphaltene destabilization is a continuous process characterized by the slow kinetic of asphaltene aggregation which results in a detection time , specific to the sensitivity of the sensor. This detection time is transformed to a shift in pressure according to the scanning pressure rate.…”

Strategic Optimization of Offshore Wind Farm Installation

“…A report from the LEANWIND project (Akbari, 2015) states physical characteristics (like lifting capability and space for component handling) to be the most important factors when picking suitable installation ports.…”

“…According to a test case in a LEANWIND report, distance from wind farm to potential ports range from 50 to 270 km (Akbari, 2015).…”

Investigation into mechanisms and kinetics of asphaltene aggregation in toluene/n-hexane mixtures

“…Because settling and deposition of asphaltenes occur by forming large aggregates of asphaltenes in oil that can be modeled by studying the Edited by Yan-Hua Sun mechanisms of aggregation, it is vital to study the asphaltene aggregation behavior in order to find an effective solution to prevent or mitigate the severity of asphaltene problems. Numerous studies have been carried out to investigate the kinetics of colloidal aggregation of different solid particles (Schaefer et al 1984;Weitz and Oliveria 1984;Sheu et al 1992;Mozaffarian et al 1997;Sun et al 2017;Maqbool et al 2011;Haji-Akbari et al 2015;Mohammadi et al 2016). Yudin et al (1998a) applied the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to explain asphaltene aggregation behavior.…”