This paper is concerned with asphaltene deposition in fluid flowing through pipelines. Brownian diffusion and drag, gravitational, thermophoresis, buoyancy, and shear removal are considered as possible mechanisms in the asphaltene deposition process. The thermo-physical properties of the fluid were obtained from Iranian oil fields. A model was used in the pipeline deposition modeling to predict...

This study has been investigated, the effects of three different polar polyacrylamides (anionic, cationic, and nonionic) on asphaltene deposition in porous media. All experiments were carried out in various dead oil flow rates (0.2, 0.1 and 0.02 cc/min) and different polymer concentrations (500, 2500, 4000 ppm). The results indicated that asphaltene precipitation was affected by the presence of...

We use time-resolved-small angle neutron scattering to study the kinetics of asphaltene nanoparticle aggregation in incompatible crude oil mixtures. We induce asphaltene aggregation by mixing asphaltene-rich Syrian crude oil ~SACO! with a paraffinic British crude oil and observe the scattered neutron intensity, I, as a function of wave number, q, over times, t, ranging from twenty minutes to ab...

The adsorption of asphaltenes onto flat solid surfaces modified with mixed self-assembled monolayers (SAMs) of aliphatic and aromatic trichlorosilanes with varying wettabilities, aromaticities, and thicknesses is tested. The mixed SAMs are characterized by means of contact angle to assess hydrophobicity and molecular and chemical uniformity, spectroscopic ellipsometry to measure the thickness o...

The problem of understanding the recognition and specific interactions in a population of yeast flocculating cells is discussed. The biochemistry, physiology and genetics of flocculation is briefly reviewed. Yeast flocculation requires the expression of a specific protein (lectin) on flocculent cells, and carbohydrate (receptors) on neighbouring cells. Adhesion experiments performed with cells ...

In this work the likelihood of asphaltene deposition problems during dynamic displacement of oil by natural gas in unconsolidated porous media is experimentally inspected. The two different rock materials, limestone and sandstone, are used as a representative of porous media. Dynamic flow experiments indicate that the increase of natural gas injection inc...

the basics of quantum mechanics and statistical thermodynamics were used to predict the potential energy and intermolecular forces of asphaltene molecules. the parameters associated with the chemical structure were also estimated for a specific asphaltene molecule to predict the mie potential function. based on the structural results, a new form of the virial eos with peneloux correction was de...

One of the most paramount processes that play a considerable role in reducing the concentration of heavy metals during estuarine mixing is flocculation. Not only does such a process cause a huge percentage of metals to come into the particulate phase, but also it provides ample nutrients for the aquatic life. In the present study, impact of such factors as salinity, pH and DO on flocculation of...

Readily available proteins were tested as renewable flocculants, and their actions were compared to that of anionic PAM, a common, commercial flocculant that requires the coaddition of a calcium ion source. Two soy proteins, a whey fraction, a porcine gelatin, and a meat & bone meal (MBM) extract were used in the flocculation test. It was found that MBM extract and porcine gelatin promoted clay...