EFFECT OF SOLVENT TYPE AND DRAINAGE HEIGHT ON ASPHALTENE PRECIPITATION FOR THE SOLVENT PERCOLATING GRAVITY DRAINAGE MECHANISM IN THE VAPOR EXTRACTION PROCESS

Summary Application of thermal and solvent enhanced-oil-recovery (EOR) technologies for viscous heavy-oil recovery in naturally fractured reservoirs is generally challenging because of low permeability, unfavorable wettability and mobility, and considerable heat losses. Vapor/oil gravity drainage (VOGD) is a modified solvent-only injection technology, targeted at improving viscous oil recovery in fractured reservoirs. It uses high fluid conductivity in vertical fractures to rapidly establish a large solvent/oil contact area and eliminates the need for massive energy and water inputs, compared with thermal processes, by operating at significantly lower temperatures with no water requirement. An investigation of the effects of solvent-injection rate, temperature, and solvent type [n-butane and dichloromethane (DCM)] on the recovery profile was performed on a single-fracture core model. This work combines the knowledge obtained from experimental investigation and analytical modeling using the Butler correlation (Das and Butler 1999) with validated fluid-property models to understand the relative importance of various recovery mechanisms behind VOGD—namely, molecular diffusion, asphaltene precipitation and deposition, capillarity, and viscosity reduction. Experimental and analytical model studies indicated that molecular diffusion, convective dispersion, viscosity reduction by means of solvent dissolution, and gravity drainage are dominant phenomena in the recovery process. Material-balance analysis indicated limited asphaltene precipitation. High fluid transmissibility in the fracture along with gravity drainage led to early solvent breakthroughs and oil recoveries as high as 75% of original oil in place (OOIP). Injecting butane at a higher rate and operating temperature enhanced the solvent-vapor rate inside the core, leading to the highest ultimate recovery. Increasing the operating temperature alone did not improve ultimate recovery because of decreased solvent solubility in the oil. Although with DCM, lower asphaltene precipitation should maximize the oil-recovery rate, its higher solvent (vapor)/oil interfacial tension (IFT) resulted in lower ultimate recovery than butane. Ideal density and nonideal double-log viscosity-mixing rules along with molecular diffusivity as a power function of oil viscosity were used to obtain an accurate physical description of the fluids for modeling solvent/oil behavior. With critical phenomena such as capillarity and asphaltene precipitation missing, the Butler analytical model underpredicts recovery rates by as much as 70%.

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Experimental Investigation of the Effect of Solvent Type and Drainage Height on the Performance of Vapor Extraction (VAPEX) Process in Heavy Oil Systems

10.2118/165447-ms ◽

2013 ◽

Cited By ~ 2

Author(s):

Farshid Torabi ◽

Mehdi Mohammadpoor

Keyword(s):

Experimental Investigation ◽

Heavy Oil ◽

Vapor Extraction ◽

Effect Of Solvent ◽

Solvent Type

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Metal(II) Coordination Polymers from Tetracarboxylate Linkers: Synthesis, Structures, and Catalytic Cyanosilylation of Benzaldehydes

Catalysts ◽

10.3390/catal11020204 ◽

2021 ◽

Vol 11 (2) ◽

pp. 204

Author(s):

Yu Li ◽

Chumin Liang ◽

Xunzhong Zou ◽

Jinzhong Gu ◽

Marina V. Kirillova ◽

...

Keyword(s):

Coordination Polymers ◽

Polycarboxylic Acid ◽

X Ray Diffraction ◽

X Ray ◽

Trimethylsilyl Cyanide ◽

Effect Of Solvent ◽

Highly Active ◽

Solvent Type ◽

Metal Organic ◽

Chloride Salts

Three 2D coordination polymers, [Cu2(µ4-dpa)(bipy)2(H2O)]n∙6nH2O (1), [Mn2(µ6-dpa)(bipy)2]n (2), and [Zn2(µ4-dpa)(bipy)2(H2O)2]n·2nH2O (3), were prepared by a hydrothermal method using metal(II) chloride salts, 3-(2′,4′-dicarboxylphenoxy)phthalic acid (H4dpa) as a linker, as well as 2,2′-bipyridine (bipy) as a crystallization mediator. Compounds 1–3 were obtained as crystalline solids and fully characterized. The structures of 1–3 were established by single-crystal X-ray diffraction, revealing 2D metal-organic networks of sql, 3,6L66, and hcb topological types. Thermal stability and catalytic behavior of 1–3 were also studied. In particular, zinc(II) coordination polymer 3 functions as a highly active and recoverable heterogeneous catalyst in the mild cyanosilylation of benzaldehydes with trimethylsilyl cyanide to give cyanohydrin derivatives. The influence of various parameters was investigated, including a time of reaction, a loading of catalyst and its recycling, an effect of solvent type, and a substrate scope. As a result, up to 93% product yields were attained in a catalyst recoverable and reusable system when exploring 4-nitrobenzaldehyde as a model substrate. This study contributes to widening the types of multifunctional polycarboxylic acid linkers for the design of novel coordination polymers with notable applications in heterogeneous catalysis.

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Extraction of 2-Acetyl-1-Pyrroline (2AP) in Pandan Leaves (Pandanus Amaryllifolius Roxb.) Via Solvent Extraction Method: Effect of Solvent

Jurnal Teknologi ◽

10.11113/jt.v67.2735 ◽

2014 ◽

Vol 67 (2) ◽

Cited By ~ 1

Author(s):

Norzita Ngadi ◽

Noor Yahida Yahya

Keyword(s):

Solvent Extraction ◽

Extraction Method ◽

Extraction Process ◽

Natural Sources ◽

Effect Of Solvent ◽

Method Effect ◽

Solvent Extraction Method ◽

Pandanus Amaryllifolius

Pandan (Pandanus amaryllifolius Roxb.) leaves are widely used in Malaysia as a source of natural flavoring. The major compound contributing to the characteristic flavour of Pandan is 2-acetyl-1-pyrroline (2AP). As the consumer requirement for use of natural flavours, extraction of components from natural sources has been sought. In this study, solvent extraction of 2AP from Pandan leaves was performed. The effect of solvent used during extraction process (i.e. methanol, ethanol, propanol) towards the yield of 2AP was investigated. The presence of 2AP was determined using GCMS. The results obtained showed that ethanol was the best solvent to extract 2AP from Pandan leaves compared to methanol as higher 2AP peak arises from ethanol chromatogram. However there is no 2AP detected when propanol was used as solvent. It is believed that polarity of the solvent plays an important role in the extraction of 2AP.

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Steady State Analysis of Heated Soil Vapor Extraction Process With Air Sparging

Heat Transfer: Volume 2 ◽

10.1115/ht2005-72272 ◽

2005 ◽

Author(s):

P. M. Mohan Das ◽

R. S. Amano ◽

T. Roy ◽

J. Jatkar

Keyword(s):

Extraction Process ◽

Soil Vapor Extraction ◽

Air Sparging ◽

Saturated Zone ◽

Vapor Extraction ◽

Combined System ◽

Discrete Phase Modeling ◽

Discrete Phase ◽

Time Required ◽

Heated Soil

Heated Soil Vapor Extraction (HSVE), developed by Advanced Remedial Technology is a Soil remediation process that has gained significant attention during the past few years. HSVE along with Air sparging has been found to be an effective way of remediating soil of various pollutants including solvents, fuels and Para-nuclear aromatics. The combined system consists of a heater/boiler that pumps and circulates hot oil through heating wells, a blower that helps to suck the contaminants out through the extraction well, and air sparging wells that extend down to the saturated region in the soil. Both the heating wells and extraction wells are installed vertically in the saturated region in contaminated soil and is welded at the bottom and capped at the top. The heat source heats the soil and the heat is transported inside the soil by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then absorbed by the extraction well. Soil vapor extraction cannot remove contaminants in the saturated zone of the soil that lies below the water table. In that case air sparging may be used. In air sparging system, air is pumped into the saturated zone to help flush the contaminants up into the unsaturated zone where the contaminants are removed by SVE well. In this analysis an attempt has been made to predict the behavior of different chemicals in the unsaturated and saturated regions of the soil. This analysis uses the species transport and discrete phase modeling to predict the behavior of different chemicals when it is heated and absorbed by the extraction well. Such an analysis will be helpful in predicting the parameters like the distance between the heating and extraction wells, the temperature to be maintained at the heating well and the time required for removing the contaminants from the soil.

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Upscaling Study of Vapor Extraction Process Through Numerical Simulation

Transport in Porous Media ◽

10.1007/s11242-012-0069-y ◽

2012 ◽

Vol 95 (3) ◽

pp. 697-715 ◽

Cited By ~ 4

Author(s):

S. Xu ◽

F. Zeng ◽

Y. Gu ◽

K. D. Knorr

Keyword(s):

Numerical Simulation ◽

Extraction Process ◽

Vapor Extraction

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Revisiting the Butler-Mokrys Model for the Vapor-Extraction Process

SPE Journal ◽

10.2118/194212-pa ◽

2019 ◽

Vol 24 (02) ◽

pp. 511-521

Author(s):

V.. Mohan ◽

P.. Neogi ◽

B.. Bai

Keyword(s):

Concentration Profile ◽

Heavy Oil ◽

Extraction Process ◽

Previous Model ◽

Oil Reservoir ◽

Vapor Extraction ◽

Oil Viscosity ◽

Solvent Vapor ◽

Vapor Interface ◽

Heavy Oil Reservoir

Summary The dynamics of a process in which a solvent in the form of a vapor or gas is introduced in a heavy-oil reservoir is considered. The process is called the solvent vapor-extraction process (VAPEX). When the vapor dissolves in the oil, it reduces its viscosity, allowing oil to flow under gravity and be collected at the bottom producer well. The conservation-of-species equation is analyzed to obtain a more-appropriate equation that differentiates between the velocity within the oil and the velocity at the interface, which can be solved to obtain a concentration profile of the solvent in oil. We diverge from an earlier model in which the concentration profile is assumed. However, the final result provides the rate at which oil is collected, which agrees with the previous model in that it is proportional to h, where h is the pay-zone height; in contrast, some of the later data show a dependence on h. Improved velocity profiles can capture this dependence. A dramatic increase in output is seen if the oil viscosity decreases in the presence of the solvent, although the penetration of the solvent into the oil is reduced because under such conditions the diffusivity decreases with decreased solvent. One other important feature we observe is that when the viscosity-reducing effect is very large, the recovered fluid is mainly solvent. Apparently, some optimum might exist in the solubility φo, where the ratio of oil recovered to solvent lost is the largest. Finally, the present approach also allows us to show how the oil/vapor interface evolves with time.

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