Experimental study of asphaltene deposition in transparent microchannels using the light absorption method

Abstract

Correlation between deposition thickness and normalized light absorption Heptane-induced asphaltene precipitation from crude oil and its deposition in a vertical transparent microchannel is investigated. The amount of asphaltene deposited on a transparent channel wall is quantified using a non-intrusive flow visualization technique based on reflected light intensity and image analysis. Asphaltene deposits strongly affect the reflected light intensity through the change of mixture color in the recorded images. An empirical equation is developed to correlate the intensity of the light absorption to the thickness of the deposited asphaltene in a transparent microchannel. Non-uniform deposition along the longitudinal direction of the microchannel is also characterized.

Physicochemical Characterization of Asphaltenes Using Microfluidic Analysis

“…Flow loops, sandpacks, and corefloods are more representative of field conditions but cannot be easily combined with in situ chemical analysis techniques. Microfluidic devices offer a fast, high-throughput, and well-controlled environment to visualize and probe the key parameters governing asphaltene precipitation and deposition within porous media. ,,− The typical length scale of microfluidic devices (μm-mm) match the representative pore sizes of the reservoir rock. − Additionally, the characteristic flow rate in the reservoir is ∼1 ft/day, and the flows are typically governed by viscous, capillary, and gravitational forces. Analogously, the flow in microfluidic devices is characterized by low Reynolds numbers flows, whereby viscous forces are larger than inertial forces.…”

Microfluidic Study of the Deposition Dynamics of Asphaltene Subfractions Enriched with Island and Archipelago Motifs

“…Asphaltenes are significant contributors to flow assurance challenges because they play a critical role in the stabilization of water-in-oil emulsions and the deposition of solids in petroleum production systems. , Asphaltenes exist in the oil matrix as relatively stable nanoaggregates. Several works suggest that a combination of intermolecular interactions such as π stacking between aromatic cores, van der Waals interactions between aliphatic moieties, and hydrogen bonding between polarizable functionalities results in strong nanoaggregation. − Destabilization of these stable nanoaggregates occurs when physicochemical/thermodynamic conditions change, such as the alterations in temperature, pressure, and composition incurred during transportation. ,− …”

Microfluidic Investigation of Asphaltenes-Stabilized Water-in-Oil Emulsions

“…Microfluidics can provide a better understanding of emulsification/demulsification mechanisms and offer in situ visualization of the coalescence phenomena using a very small amount of crude oil and water (on the order of microliters). Well-controlled and high-throughput microfluidic devices have been utilized to provide insights into the physicochemical hydrodynamics of oil-related issues including flow assurance and enhanced oil recovery (EOR). − Recent studies have described the emulsification/demulsification process of model systems using microfluidics. Christopher et al investigated the collision of water and water/glycerol droplets dispersed in silicone oil with no surfactant added using microfluidic T-junctions.…”