Modeling microbial-induced oil viscosity reduction: Effect of temperature, salinity and nutrient concentration

According to the mechanisms of carbon dioxide miscible flooding and previous researchers’ work on synthesis of CO2-soluble surfactant, Citric acid isoamyl ester was synthesized, and it’s oil solubility and the rate of viscosity reduction both in oil-water system and oil were evaluated. And then we found that this compound can solve in oil effectively; the optimum mass of Citric acid isoamyl ester introduced in oil-water system is 0.12g when the mass ratio of oil and water is 7:3 (crude oil 23.4g, formation water 10g) and the experimental temperature is 50°C , the rate of viscosity reduction is 47.2%; during the evaluation of the ability of Citric acid isoamyl ester to decrease oil viscosity, we found that the optimum dosage of this compound in 20g crude oil is 0.2g when the temperature is 40°C, and the rate of viscosity reduction is 7.37% at this point.

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Density and Drag Reduction With Hollow Glass Additives

Volume 5: Materials Technology; Petroleum Technology ◽

10.1115/omae2014-23401 ◽

2014 ◽

Author(s):

Bahri Kutlu ◽

Evren M. Ozbayoglu ◽

Stefan Z. Miska ◽

Nicholas Takach ◽

Mengjiao Yu ◽

...

Keyword(s):

Drag Reduction ◽

Rheological Behavior ◽

Drilling Fluid ◽

Hydraulic Drag ◽

Effect Of Temperature ◽

Survival Ratio ◽

Fluid Density ◽

Hollow Glass ◽

Glass Spheres ◽

Reduction Effect

This study concentrates on the use of materials known as hollow glass spheres, also known as glass bubbles, to reduce the drilling fluid density below the base fluid density without introducing a compressible phase to the wellbore. Four types of lightweight glass spheres with different physical properties were tested for their impact on rheological behavior, density reduction effect, survival ratio at elevated pressures and hydraulic drag reduction effect when mixed with water based fluids. A Fann75 HPHT viscometer and a flow loop were used for the experiments. Results show that glass spheres successfully reduce the density of the base drilling fluid while maintaining an average of 0.93 survival ratio, the rheological behavior of the tested fluids at elevated concentrations of glass bubbles is similar to the rheological behavior of conventional drilling fluids and hydraulic drag reduction is present up to certain concentrations. All results were integrated into hydraulics calculations for a wellbore scenario that accounts for the effect of temperature and pressure on rheological properties, as well as the effect of glass bubble concentration on mud temperature distribution along the wellbore. The effect of drag reduction was also considered in the calculations.

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REDUCING OF OIL VISCOSITY UNDER PULSE ARC ELECTROHYDRAULIC DISCHARGE

Вестник ГГНТУ. Технические науки ◽

10.34708/gstou.2020.69.95.004 ◽

2020 ◽

pp. 25-32

Author(s):

В. В. Лыков ◽

Л. Ш. Махмудова ◽

М. Х. Джабраилова ◽

Х. Ш. Лаиева

Keyword(s):

Relaxation Time ◽

Rheological Properties ◽

Viscosity Reduction ◽

Oil Viscosity ◽

The Cost ◽

Pulsed Arc ◽

Pulsed Arc Electrohydraulic Discharge ◽

Electrohydraulic Discharge

В работе исследовалось воздействие импульсного плазменного (ИПВ) электрогидравлического разряда на реологические свойства нефтей с месторождений Октябрьское и Старогрозненское Чеченской Республики и Зимняя Ставка Ставропольского края. В результате ИПВ наблюдалось снижение вязкости нефти с месторождения Октябрьское на 15%, с месторождения Старогрозненское - на 25%, с месторождения Зимняя Ставка - на 50%. Показана зависимость степени снижения вязкости после ИПВ от содержания парафинов в нефти. Чем больше процент содержания парафинов, тем больше процент снижения вязкости. Время восстановления вязкости поле ИПВ (время релаксации) превышало 7 дней, что позволяет транспортировать нефти на большие расстояния, существенно сокращая затраты на путевые подогреватели и насосы. Можно ожидать сокращение затрат на борьбу с парафиновыми отложениями на стенках трубопроводов (АСПО) и насосно-компрессорных труб (НКТ) из-за снижения концентрации парафинов при ИПВ. The paper investigated the effect of pulsed arc electrohydraulic discharge (PAED) on the rheological properties of oil from the Oktyabrskoye and Starogroznenskoye fields in the Chechen Republic and Zimnyaya Stavka in the Stavropol territory. As a result of PAED, the viscosity of oil from the Oktyabrskoye field decreased by 15%, from the Starogroznenskoye field by 25%, and from the Zimnyaya Stavka field by 50%. The dependence of the degree of viscosity reduction after PAED on the paraffin content in oils is shown. The higher the percentage of paraffin content, the greater the percentage of viscosity reduction. The time of recovery of the viscosity after PAED (relaxation time) exceeded 7 days, which allows transport oil over long distances, significantly reducing the cost of track heaters and pumps. We expect a reduction in the cost of controlling paraffin deposits on the walls of pipelines and tubing due to a decrease in the concentration of paraffins after PAED.

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Asphaltene Deposition Induced by Carbon Oxide and its Influence on Displacement Efficiency

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.2451 ◽

2012 ◽

Vol 594-597 ◽

pp. 2451-2454

Author(s):

Feng Lan Zhao ◽

Ji Rui Hou ◽

Shi Jun Huang

Keyword(s):

Crude Oil ◽

Oil Recovery ◽

Carbon Oxide ◽

Viscosity Reduction ◽

Core Flooding ◽

Displacement Efficiency ◽

Oil Composition ◽

Oil Viscosity ◽

Asphaltene Deposition ◽

Total Oil

CO2is inclined to dissolve in crude oil in the reservoir condition and accordingly bring the changes in the crude oil composition, which will induce asphaltene deposition and following formation damage. In this paper, core flooding device is applied to study the effect of asphaltene deposition on flooding efficiency. From the flooding results, dissolution of CO2into oil leads to recovery increase because of crude oil viscosity reduction. But precipitated asphaltene particles may plug the pores and throats, which will make the flooding effects worse. Under the same experimental condition and with equivalent crude oil viscosity, the recovery of oil with higher proportion of precipitated asphaltene was relatively lower during the CO2flooding, so the asphltene precipitation would affect CO2displacement efficiSubscript textency and total oil recovery to some extent. Combination of static diffusion and dynamic oil flooding would provide basic parameters for further study of the CO2flooding mechanism and theoretical evidence for design of CO2flooding programs and forecasting of asphaltene deposition.

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Indoor Study of Viscosity Reducer for Thickened Oil of Huancai

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.547 ◽

2012 ◽

Vol 268-270 ◽

pp. 547-550

Author(s):

Qing Wang Liu ◽

Xin Wang ◽

Zhen Zhong Fan ◽

Jiao Wang ◽

Rui Gao ◽

...

Keyword(s):

Interfacial Tension ◽

Oil Recovery ◽

Heavy Oil ◽

High Viscosity ◽

Oil Field ◽

Viscosity Reduction ◽

Oil Viscosity ◽

Low Viscosity ◽

Viscosity Reducer ◽

Oil Water

Liaohe oil field block 58 for Huancai, the efficiency of production of thickened oil is low, and the efficiency of displacement is worse, likely to cause other issues. Researching and developing an type of Heavy Oil Viscosity Reducer for exploiting. The high viscosity of W/O emulsion changed into low viscosity O/W emulsion to facilitate recovery, enhanced oil recovery. Through the experiment determine the viscosity properties of Heavy Oil Viscosity Reducer. The oil/water interfacial tension is lower than 0.0031mN•m-1, salt-resisting is good. The efficiency of viscosity reduction is higher than 90%, and also good at 180°C.

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High-Pressure Data and Modeling Results for Phase Behavior and Asphaltene Onsets of Gulf of Mexico Oil Mixed With Nitrogen

SPE Reservoir Evaluation & Engineering ◽

10.2118/166097-pa ◽

2014 ◽

Vol 17 (03) ◽

pp. 384-395 ◽

Cited By ~ 4

Author(s):

Odd Steve Hustad ◽

Na Jia ◽

Karen Schou Pedersen ◽

Afzal Memon ◽

Sukit Leekumjorn

Keyword(s):

High Pressure ◽

Gulf Of Mexico ◽

Phase Behavior ◽

Oil Recovery ◽

Positive Impact ◽

Viscosity Reduction ◽

Fluid Composition ◽

Viscosity Data ◽

Oil Viscosity ◽

Reservoir Fluid

Summary This paper presents fluid composition, high-pressure pressure/volume/temperature (PVT) measurements, and equation-of-state (EoS) modeling results for a recombined Tahiti oil, Gulf of Mexico (GoM), and for the oil mixed with nitrogen in various concentrations. The data include: Upper and lower asphaltene onset pressures and bubblepoint pressures for the reservoir fluid swelled with nitrogen. At the reservoir conditions of 94 MPa (13,634 psia) and 94°C (201.2°F), asphaltene precipitation is seen after the addition of 27 mol% of nitrogen. Viscosity data for the swelled fluids showing that the addition of nitrogen significantly reduces the oil viscosity. Slimtube runs indicating that the minimum miscibility pressure (MMP) of the oil with nitrogen is significantly higher than estimated from published correlations. The data were modeled with the volume-corrected Soave-Redlich-Kwong (SRK) EoS and the perturbed-chain statistical association fluid theory (PC-SAFT) EoS. Although both equations provide a good match of the PVT properties of the reservoir fluid, PC-SAFT is superior to the SRK EoS for simulating the upper asphaltene onset pressures and the liquid-phase compressibility of the reservoir fluid swelled with nitrogen. Nitrogen-gas flooding is expected to have a positive impact on oil recovery because of its favorable oil-viscosity-reduction and phase behavior effects.

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