Tarun Kumar Naiya

Use of a Novel Natural Surfactant for Improving Flowability of Indian Heavy Crude Oil

Application of novel natural surfactant for enhancing rheological properties including pour point, viscosity, thixotropic behavior, yield stress, and interfacial tension of Indian heavy crude oil was investigated. The surfactant was prepared in the laboratory using extracts from Sapindus mukorossi (soapnut) plant. Viscosity reduced by 80%, thixotropic area by 94.64%, yield stress by 98%, and interfacial tension by 97%. The study also provides the possible mechanism behind improvement of the rheological properties through FTIR spectroscopic analyses. They showed lowering of concentration of C˭O and C˭C groups in surfactant-crude mixture indicating the effectiveness of the surfactant.

The effect of a bio additive on the viscosity and the energy requirement on heavy crude oil flow

ABSTRACT The influence of potato starch as natural additive on the flow of heavy crude oil-water in pipeline was investigated. Measured parameters were viscosity, drag, energy analysis and power requirement in a horizontal pipeline at various temperatures, flow rates and concentrations of potato starch. It was found that addition of 2000 ppm potato starch to the 85% Heavy crude oil+15% water mixture at 40°C decreased viscosity by 80.24% and head loss by 7.55 × 10− 4 m at 60 LPM. Drag reduced up to 91% and power saving increased up to 38.24% after adding 2000 ppm of potato starch to same mixture at 60 LPM.

Rheological modeling and drag reduction studies of Indian heavy crude oil in presence of novel surfactant

ABSTRACT Viscosity and rheology modeling of heavy crude oil were studied at different shear rate and temperature with and without naturally extracted surfactant Mahua. Drag reduction analysis was done in 2”-ID, 2.5 m horizontal pipeline at different temperatures and flow rates. Viscosity was reduced by 60.4% after addition of 1000 ppm Mahua at 50°C. Modeling analysis showed that crude oil-surfactant samples followed Power law model with high regression coefficients. Maximum drag reduction of 94.8% occurred after adding 2000 ppm Mahua to 85% heavy oil+15% water at 40°C and at a flow rate of 50 LPM.

Simulation of single phase non-Newtonian flow characteristics of heavy crude oil through horizontal pipelines

ABSTRACT The effect of diameter, velocity, and temperature on flow properties of heavy crude oil in three horizontal pipelines using computational fluid dynamics (CFD) was studied. The flow characteristics were simulated by using CFD software, ANSYS Fluent 6.2. The mesh geometry of the pipelines having inner diameter of 1, 1.5, and 2 inch were created by using Gambit 2.4.6. From grid independent study, 221, 365 mesh sizes were selected for simulation. The CFD ANSYS Fluent 6.2 Solver predicted the flow phenomena, pressure, pressure drop, wall shear stress, shear strain rate, and friction factor. A good agreement between experimental and CFD simulated values was obtained.

Effect of pour point depressant on wax deposition and drag reduction in horizontal pipelines

ABSTRACT A newly synthesized pour point depressant (PPD) was used to decrease the wax deposition thickness and drag force during a waxy crude oil flow in two horizontal pipes of length 2.5 m each and inner diameters 1 inch and 2 inches. The flow rates of 80–120 LPM were used. 1,000-ppm PPD reduced the thickness of wax deposited by 31% and 72% at 120 LPM and 30°C in 1-inch and 2-inch pipes, respectively. There was about 15% drag reduction in both the pipes at 30°C and 120-LPM flow rate after adding 1,000-ppm PPD.

Investigation of novel extracted surfactant on rheological properties of heavy crude oil

Naturally extracted surfactant from tropical Indian plant Madhuca longifolia was used to enhance flow properties of heavy crude oil through pipelines. Experimental measurements include viscosity, yield stress, viscoelastic properties, pour point, SARA analysis, microscopic studies and FTIR studies. Experimental verification of Power Law model was justified. Crude oil surfactant mixtures tend to behave like Newtonian fluid as surfactant concentration was increased from 500 to 2,000 ppm. Viscosity of crude with 2,000 ppm surfactant at 30°C was almost same as that of pure crude at 50°C. Presence of surfactant significantly reduced elastic and complex moduli of heavy crude oil at 30°C. Yield stress of crude oil reduced from 0.9 to 0.017 Pa with surfactant addition at 30°C. Microscopic studies showed surfactant addition reduced size of wax crystals appreciably. FTIR studies implied that aldehydic and amine groups are responsible for high viscosity and their concentration reduced after addition of surfactant Madhuca longifolia. [Received: August 4, 2015; Accepted: November 28, 2015]

Design of novel chemical solvent for treatment of waxy crude

Deposited wax in pipelines and well bores are not easily recoverable due to its solidification over time. This is responsible for losses in production. In this paper, chemical solvent derived from laboratory was used to recover the solidified wax. Twelve chemical solvents and three commercial dispersants were mixed in different volumetric proportions to study their solubility effect on waxy crude oil. Optimised solvent mixture capable of dissolving wax material was used on a laboratory prototype experiment to measure the recovery of deposited wax at different temperatures (pour point of crude oil to 90°C). Optimum composition of solvent was based on its toxicity, flammability, availability and other contributing factors like cost and recoverability. The formulated solvent dissolved about 72% and 83% wax after three hours and six hours of soaking time respectively at 25°C. Results implied that formulated solvent have immense potential to recover solidified wax in wellbores and in pipelines. [Received: January 10, 2016; Accepted: March 13, 2016]

Effect of extracted natural surfactant on flow behaviour of heavy crude oil

This research article investigates experimental techniques to determine applicability of a natural surfactant on crude oil rheological behaviour through pipelines. Three crude oil samples were obtained from ONGC, Gujarat. The surfactant was extracted in laboratory using extracts from naturally occurring plant sapindus mukorrossi or soapnut. The effect of this surfactant on wax crystal structure and crystal size distribution was analysed using cross polarised light microscope and dynamic light scattering techniques. The flow characteristics investigated included pour point and viscosity. Results obtained using dynamic light scattering provided a remarkable reduction in area of wax crystals after addition of surfactant. Microscopic studies showed change in size and structure of wax crystals establishing effectiveness of surfactant. Pour point and viscosity decreased to significant value after adding 4% w/w surfactant to the crude oil samples. The study also determined the possible mechanism behind improvement of rheological properties through Fourier transform infrared spectroscopic analyses. [Received: December 12, 2014; Accepted: June 24, 2015]

Effect of Natural and Synthetic Surfactant on the Rheology of Light Crude Oil

Comparative effectiveness of natural surfactant extracted from Sapindus mukorossi in laboratory and commercial surfactant Brij 30 was determined. Light crude oil was collected from ONGC, Gujarat, India. Its pour point and viscosity decreased significantly after adding surfactants. Wax crystal structure and crystal size distribution was analyzed using cross polarized light microscope and dynamic light scattering techniques. There was remarkable reduction in radius of wax crystals after addition of both the surfactants. Microscopic studies showed significant change in size and structure of wax crystals favoring reduction in viscosity. The possible mechanism behind improvement of flow properties was also analyzed through FTIR studies.