Transportation Of Heavy Crude Oil Research Articles

Drag Reduction Related to Boundary Layer Control in Transportation of Heavy Crude Oil by Pipeline: A Review

Drag Reduction Related to Boundary Layer Control in Transportation of Heavy Crude Oil by Pipeline: A Review

Physico - Chemical Studies of Indian Crude Oil

Abstract: Crude oil is a complex mixture of non-metallic components like Sulphur, Nitrogen, Oxygen, and other elements with hydrocarbons. Crude oil is distinguished by several chemical and physical features that play an essential role in the oil industry. These qualities are critical in making decisions in the exploration and production of crude oil. Heavy crude oil is highly viscous crude oil with high Asphaltene content and API in the range of 10-25. Especially, transportation of Heavy Crude oil is herculean task for Petroleum industry. As a result, the study of physical and chemical properties becomes crucial for the petroleum industry. The current work deals with the investigation of physico-chemical characteristics of Indian crude oil.

Preparation and performance evaluation of oil-tolerant and easy-wetting viscoelastic system for enhancing the stability of highly viscous oil-water lubricated flow

Based on the free sliding phenomenon of the monopterus albus in the cave, an oil-tolerant and easy-wetting viscoelastic system (A3B4C3E5F2) was selected and compounded as a possible lubricant to enable the transportation of heavy crude oil. In the viscoelastic system, the final floating equilibrium velocity of LD1 crude oil droplets with a diameter of about 5 mm is 0.01853 mm/s, and the floating resistance coefficient (C D) is 11067862, which shows favorable oil suspension performance. When the shear rate is approximately zero, the viscosity of the viscoelastic system is about 7000 mPa·s. However, when the shear rate is up to100 1/s, the viscosity is only about 32 mPa·s. A high viscoelastic film is formed at shutdown or low flow rates. Conversely, a low viscosity liquid ring formed at high flow rate. After being wet by easy-wetting viscoelastic system, the contact angle between LD1 crude oil and common pipe materials is wider than 160° at 30 min. The incubation time (t 0) and the wettability composite index (WCI) are shorter than 1800 s and higher than 4800, respectively. Upon stability evaluation, the system can maintain good viscoelasticity and wettability in the range of temperature (5 ∼ 90 °C), oil content (0 ∼ 15 wt.%), and shear rate (0 ∼ 1000 1/s), respectively.

Techno-economic analysis of heating techniques for transportation of heavy crude oils by land pipeline

Three approaches (heat exchangers with steam, heat exchangers with thermal oil, and direct fired heaters) were analyzed for heating pipeline to transport a heavy crude oil (viscosity of 62,745 cSt a 15.6 °C, and 11.78° API gravity). The selected pipeline has a length of 62.7 km and transports 33.12 m3/h (5000 BPD) of heavy crude oil. With the calculated temperature drop (4.39 °C/km) and pressure drop (0.25 kg/cm2/km), five heating and pumping points each 12.53 km were determined to maintain the required temperature and pressure for the transportation of heavy crude oil. For each heating system, mass and energy balance was done to calculate the size of equipment and utilities consumption. Capital expenditures (CAPEX) and operational expenditures (OPEX) were obtained to identify which heating system exhibits the lowest operating costs. The results indicate that the best heating system is with direct fired heaters from both technical and economic points of view (lower number of equipment, easy and flexible operation, commercial experience, and lower consumption of utilities). OPEX and CAPEX for heating system is with direct fired heaters were 0.32 USD/bbl and 0.78 USD/bbl, respectively. This indicates that the price of heavy crude oil should be 1.1 USD/bbl higher than that at the production point. By means of a sensitivity analysis, it was demonstrated that temperature drop is the determining variable that affects the number of heating points. Increasing temperature from 4.39 to 7 °C/km increased the number of heating point from 5 to 8. A 50% increase of OPEX (utilities) resulted the total costs to be 35% higher with respect to the base case for the evaluated heating systems.

Flow Improvement and Viscosity Reduction for Crude Oil Pipelines Transportation Using Dilution and Electrical Field

One of the great challenges in pipeline transportation of heavy crude oil is the effect of viscosity on flow rate. By using viscosity reduction techniques, crude oil flow ability can be enhanced. However, the dual effect of dilution and electric fields on crude oil flow ability is still not well addressed. The main goal of this study is to reduce viscosity and improve the flow rate of heavy crude oil through pipelines using dual techniques of electrical field and dilution. The optimization technique was used to investigate the interaction effects of experimental variables on the objective function. As compared to crude oil treated solely by dilution or electrical field, the dual treatment could result in more substantial reductions in viscosity. In this experiment, at first, the dilution's impact is studied. Acetone was used as a diluent in different concentrations. The great viscosity reduction is about 21.98% when adding 20 wt. % of acetone. Secondly, when the effect of the electric field has been studied, a reduction in viscosity of about 35.6% was observed when 36.67(v/cm) is applied. Lastly, the effect of combined treatment (dilution and electric field) has been investigated according to factorial design. The optimum viscosity reduction is about 61.856% at 11 wt. % acetone and 36.67 (v/cm) of the electric field.

Fouling monitoring in oil-water flow using density profile

In water lubricated transportation of heavy crude oil, fouling monitoring on the walls of the pipe is fundamental, since it reflects in the cost of transportation. Although such phenomenon has been discussed by many researchers, more of experimental and theoretical evaluations have been carried out than numerical ones. For this reason, this work was aimed at using laminar Level-set (numerical method) to identify oil fouling (through oil density magnitude identification) on the upper and lower walls of a round horizontal pipe during water lubricated transportation. In order to achieve such objective, fluid constants (found in literature) and operational conditions established experimentally were applied to simulate and observe the density flow profiles along the upper and lower walls of a 2D pipe. Prior to the simulation process, a grid convergence test was carried out in order to establish a mesh which was capable of representing the flow characteristics, and at the same time reducing computational cost. Additionally, laminar Level-set was validated through comparing Reynolds numbers obtained from its application to analytical values calculated at the same conditions. Two main volumetric flow profiles (plug and core-annular flow- CAF) with their respective density profiles were obtained. In both cases, oil fouling was identified at specific regions of the pipe's upper and lower walls, presenting densities closer to 918.8 kg/m3.

A Multi-Phase Closed Pipelines Simulation Approach for Transportation of Heavy Oil with Openfoam in HPC

Transportation of heavy crude oil through closed pipelines is a challenging issue both in offshore and in land oil transportation. The scope of the present paper deals with the computational modelling of two phase extra heavy crude oil & water flow in OpenFOAM. In order to validate the flow model the pressure variation along the length of the channel are investigated, which shows the typical plot of two roughly constant pressure lines at different levels connected by a sharp change of pressure at the interface of two fluids. The validated flow model, aims at optimizing the kinematic viscosity of the multiphase flow, by regulating the flow velocity of the components, such that there is minimum viscous heat loss and hence minimum pump power consumption from the horizontal centrifugal pumping system. Using the OpenFOAM(Open Source Field Operation & Manipulation) software, which is free opensource software, developed in 2004, under GNU general public license, paraview has been used here as post processing tool. Multiphase flow simulation is done using the k-ɛ turbulence model in HPC of kanchenjungha cluster, NIT Sikkim, India.

Magnetite nanoparticle mediated catalytic aquathermolysis of Omani heavy crude oil

The worldwide demand for energy continues to grow and the production of heavy crude is escalating due to shortage of conventional light crude. The transportation of heavy crude oil from the head-well to the refinery is a challenging task due to its high viscosity and low API gravity. Catalytic aquathermolysis is one of the most significant and cost-effective viscosity reduction techniques employed in the up gradation of the crude oil at elevated temperatures and hence to enhance oil extraction process. In this study, catalytic aquathermolysis of Omani heavy crude oil was performed using magnetite nanoparticles (NPs). The NPs were synthesised by reverse co-precipitation method using iron salts in alkaline medium. The synthesised NPs were characterized using Scanning Electron Microscopy (SEM), X-Ray Powder Diffraction (XRD), Energy Dispersive X- Ray analysis (EDX) and Fourier Transform Infrared Spectroscopy (FTIR). The XRD results exhibited a characteristic peak confirming the high purity of iron oxide nanoparticles. The FTIR spectral analysis designated two well-defined peaks corresponding to wave numbers of 500 ​cm−1 and 630 ​cm−1, endorses the presence of Fe–O. The catalytic aquathermolysis experiments were carried out in a Parr high temperature-high pressure batch reactor at different experimental conditions. The processing parameters in temperature range of 250 ​°C - 300 ​°C, 0.1% to 0.3% catalyst loading, water to oil ratio of 1:7 to 3:7 with 24–72 ​h of reaction time. The initial pressure in the reactor was maintained at 32 ​bars and the optimization was performed using the Taguchi method to maximize the level of heavy oil. An orthogonal array was employed to analyse the effects of mean response and mean signal-to-noise ratio (S/N) to upgrade the heavy oil. The regression analysis was used to establish a relationship between the viscosity and experimental parameters. The experimental outcomes indicates that the maximum reduction in viscosity occurred at a processing temperature of 300 ​°C, 1:7 ​W/O ratio, 0.1 ​wt% of catalyst concentration and 48 ​h of reaction time. Similarly, the optimum conditions for the reduction in API gravity were obtained at 280 ​°C temperature, 3:7 ​W/O ratio, 0.2 ​wt% of catalyst concentration and a reaction time of 24 ​h.

CFD investigation on characteristics of heavy crude oil flow through a horizontal pipe

Transportation of heavy crude oil via pipelines possesses many technological issues that are inherently flow related. Accurate prediction of flow characteristics is an essential step for a reliable piping design of transporting the crude oil. A rheology-based Computational Fluid Dynamics (CFD) model of the Iraqi heavy crude oil flow through a horizontal pipe (1 m length of 3/4 in. inside diameter) was developed using the commercial software Ansys 15 Fluent. By using power law rheological model, the Iraqi heavy crude oil exhibits a non-Newtonian dilatant behavior over the examined shear rate range of 1–40 s−1. The proposed axi-symmetric CFD model identifies velocity profile and generates values of friction factor, which are validated with experimental measurements. Additionally, wall shear stress and entrance length were numerically predicted and compared with well-established correlations from the literature for Non-Newtonian flow. Detailed results of the CFD model exhibited a reliable prediction of the characteristics of heavy crude oil flow.

A study on cashew nut shell liquid as a bio-based flow improver for heavy crude oil

Transportation of heavy crude oil through pipelines poses a great challenge in oil and gas industry. Crude oil chokes the pipelines when the temperature drops below the pour-point temperature. In the present study, a bio-based additive, i.e., Cashew Nut Shell Liquid (CNSL) has been tested as a flow improver for heavy crude. CNSL was obtained from waste cashew nut shell by means of mechanical extraction, and it was completely characterized. Similarly, the crude oil used in the study was characterized for its physio-chemical properties. Also, the crude oil was subjected to Saturates, Aromatics, Resins and Asphaltene analysis and Fourier Transform Infra-Red analysis. The raw and additive-treated crude oil with different CNSL dosages were subjected to pour-point and rheology measurements and optical micro-imaging analysis which indicated a remarkable improvement in flow whereby an optimum dose of 2000 ppm was observed. Furthermore, the effects of different parameters like shear rate, concentration of the flow improver and the effect of temperature on the crude oil flowability were studied. The process variables were optimized by means of Taguchi method, and the percentage contribution of each parameter was identified with the help of ANOVA table. The results indicate that a remarkable improvement in flow was observed at an optimum dose of 2000 ppm. The contribution of the concentration was found to be around 53%, whereas the contributions of the shear rate and the temperature were only 18.08 and 28.91%, respectively. Therefore, it has been observed that CNSL flow improvers extracted from cheap reasonable resources are more effective as they are cost-effective and eco-friendly when compared to conventional additives.

Viscosity Reduction of Indian Heavy Crude Oil by Emulsification to O/W Emulsion Using Polysorbate‐81

AbstractPipeline transportation is the most convenient means of transportation of crude oil continuously and economically from production site to refinery. However, transportation of heavy crude oil (HCO) through pipelines is difficult due to its high viscosity. The high viscosity of heavy crude oil is mainly due to the presence of poly‐aromatic compounds like resins and asphaltenes. Emulsification of HCO using surfactant is believed to be the most favorable technique to reduce the viscosity of HCO for efficient pipeline transport. In the present study, oil‐in‐water (O/W) emulsion has been formulated using a non‐ionic surfactant Polyoxyethylene (5) sorbitan monooleate (PS‐81) at different pH, surfactant concentration, and oil content. Box–Behnken response surface method has been used to optimize two responses, apparent viscosity and emulsion stability index (ESI). The optimal values of the parameters found are 75%v/v oil content, 2.5%w/v surfactant concentration, and pH value of 7 at which experimental value of emulsion viscosity is 0.2162 Pa·s, at 150 RPM, with a reduction of viscosity by 95.8% and having ESI of 98.16 after 24 h at 30°C.

Life under an oil slick: response of a freshwater food web to simulated spills of diluted bitumen in field mesocosms

Heavy crude oil transportation over land is increasing, yet the ecological impacts of spills, particularly of diluted bitumen, in freshwater environments remain poorly understood. We simulated spills of diluted bitumen in 1400 L land-based mesocosms containing water and sediments from a boreal, oligotrophic lake and monitored the response of natural planktonic communities over 11 days. Most species of phytoplankton (chrysophytes and dinoflagellates) and zooplankton (copepods and cladocerans) were sensitive to oil, exhibiting >70% overall abundance reductions in response to the spills. Declines in nano- and microphytoplankton were short-lived and began to recover after the oil sank, whereas picophytoplankton and zooplankton populations remained depressed at the end of the experiment. In contrast, oil spills stimulated bacteria known to degrade hydrocarbons, especially Alphaproteobacteria, whereas Gammaprotobacteria (a common marine oil spill bacterial class) increased less. This is the first experiment to examine the effects of diluted bitumen in a multitrophic freshwater community.

Impact of Asphaltene Presence in Heavy Crude Oil and Its Separation Technique

Heavy crude oil is the crude oil with no gas composition and major constituents are asphaltene, resins, saturates and aromatics. Heavy crude oil is capable of producing a low high valued products and high low valued products. Asphaltene is a molecular substance that acts as a binding molecule to help in the recovery of heavy crude oil. On the contrary, an asphaltene deposition becomes troublesome in the heavy crude oil transportation through pipelines. In this research article, the heavy crude oil was collected from the western part of Indian oilfield and subjected to the separation of asphaltene content by the addition of aliphatic solvent. The results of separation of asphaltene from the heavy crude oil by the addition of n-heptane and n-hexane were found to be 15 wt. % and 17 wt. %. The asphaltene will cause moderate deposition problem during the production and transportation of investigated heavy crude oil.

Features of very heavy crude oil transportation

The paper discusses the features of very heavy crude oil transportation in pipelines as exemplified by foreign transportation techniques. Special focus is given on the processes of rheologically complex behavior of waxy crude oils.

Viscosity reduction of heavy crude oil by dilution with hydrocarbons obtained via chemical recycling of plastic wastes

The increasing energy demand is persuading oil companies to exploit unconventional reserves of heavy and extra heavy crude oil, which are characterized for their elevated viscosities and upraised production costs. Expensive flow modifiers are often used to lower the viscosity of heavy crude oils so that pipeline transportation becomes viable. In this study, thermal cracking tests were conducted to obtain hydrocarbons (condensate) of lower molar masses, from common plastic wastes. Physical properties of the products were measured, such as viscosity, density, pour point, cloud point and aniline temperature. Due to their chemical similarity, the hydrocarbon products from the tertiary recycling of postconsumer low density polyethylene (LDPE) plastic bags were used to dilute a heavy crude oil (12°API) and lower its viscosity. Results showed a viscosity reduction of 90% at room temperature of a 5:25 vol:vol blend of hydrocarbons/heavy crude oil. This paper proposes an alternative solution for two alarming global problems: waste plastics recovery and optimal transportation of heavy crude oil; However, an industrial application of this process would have to be combined with municipal solid waste collection and pre-treatment technologies.

Hydrodynamics and energy analysis of heavy crude oil transportation through horizontal pipelines using novel surfactant

Improvement of flow properties of crude oil through pipelines, the effect of temperature, diameter, water cut, and novel extracted surfactant on pressure drop, shear viscosity was studied along with energy analysis. The impact of diameter, temperature, and the addition of novel surfactant extracted from Madhuca longifolia (Mahua) on pressure drop, shear viscosity, pumping power saving and flow increment were investigated during heavy crude oil flow in horizontal pipelines. Minimum pressure drop was observed in 0.0508 m ID pipeline owing to the collective effect of temperature and 2000 ppm Mahua during the flow of 85% heavy crude oil+15% water. Shear viscosity reduced appreciably in 0.0381 m and 0.0508 m ID pipelines after addition of 2000 ppm Mahua at a temperature of 50 °C. Maximum power saving (130.8%) was achieved and maximum flow increment of 121.8% was accomplished after addition of 2000 ppm Mahua to 85% heavy oil and 15% water mixture during its transportation in 0.0508 m ID pipeline at a 50 °C and at the rate of 7.2 m3/hr. The natural surfactant is substantially efficient to decrease the pumping power consumption for heavy crude oil transportation. It was concluded that the extracted novel natural surfactant is very beneficial for being used as an emulsifier, viscosity reducer, flow improver and also an alternative for the commercial surfactant.

Tertiary Amine‐Naphthenic Acid Self‐Assembled Surfactants for Viscosity Reduction of Crude Oil

AbstractThe formation of low‐viscosity emulsions is a vital method for viscosity reduction of crude oil. Naphthenic acids, which are present in crude oil, are potential surface‐active substances. Tertiary amines with CO2 response can be self‐assembled in situ with the naphthenic acids in the crude oil to form a surfactant, which can emulsify the heavy crude oil and water to form an emulsion. The emulsion can be easily demulsified in the presence of CO2. N,N‐Dimethylbutylamine, N,N‐dimethyloctylamine, and N,N‐dimethyldodecylamine were used to prepare heavy crude oil emulsions in this work. This convenient emulsification and demulsification approach provides a new concept for pipeline transportation of heavy crude oil.

Effect of Aromatic and Aliphatic Pendants in Poly(maleic acid amide-co-vinyl acetate) on Asphaltene Precipitation in Heavy Oil

Asphaltene precipitation often brings difficulties to the recovery and transportation of heavy crude oil. Poly(maleic acid amide-co-vinyl acetate) copolymers with various aromatic (phenyl, naphthyl, and benzimidazole) pendants and/or aliphatic (octyl, tetradecyl, and octadecyl) grafts were synthesized and found to be capable of dispersing asphaltenes effectively. To study the influence of aromatic and aliphatic pendants in copolymers on asphaltene precipitation behaviors, the initial precipitation point, turbidity, and size of asphaltene precipitates from model heavy oils in the presence and absence of copolymers were determined by UV–vis spectroscopy, turbidity meter, and dynamic light scattering, respectively. The effect of copolymers on the viscosity of Tahe heavy oil with high asphaltene content was investigated by the rheological approach. The results revealed that the copolymers with both aromatic and aliphatic pendants dispersed asphaltene, reduced its precipitates, and thus improved the flowabilit...

Vortex and Oil Distribution of Oil-Water Annular Flow through Ball Valve

The study on the flow behave inside of a ball valve is important for heavy crude oil transportation. Owe to the fast progress of the numerical technique, it becomes an effective way to observe the flows inside a valve and to analyze the flow structure of the oil-water core annular flow. In the present study, the simulation of the oil-water core annular flowing through the valve is conducted by combined the VOF and CSF model, and the effects of open rate on vortex and oil distribution characteristics are analyzed. The simulated data is a satisfactory match with empirical value and the experimental results. The results show that there are lots of vortexes inside and behind the valve, the coordinate values of the vortex decrease and the aggregation rate increases with an increase in open rate. As the input velocity increases, the change rate of the vortex position is greater, and the oil aggregation rate decreases, the highly viscous oil with has greater aggregation rate after flow through the valve, and the variation of the vortex core position is relatively slow. As the vortex flow across the oil core, the oil will be scattered and contributes to the instability of the annular flow.

Multimodal Transportation Flows in Energy Networks with an Application to Crude Oil Markets

Network models of energy markets have been beneficial for analyses and decision-making to tackle challenges related to the production, distribution and consumption of energy in its various forms. Despite the growing awareness of environmental and safety impacts of fuel transfer, such as emissions, spills and other harmful effects, existing energy models for various types of networks are yet to fully capture modal distinctions which are relevant to providing pathways to limiting these impacts. To address this deficit in detailed multimodal analyses, we have built on recent work to develop a partial-equilibrium model that incorporates the representation of multimodal fuel transfer within energy networks. In a novel application to the North American crude oil market, we also demonstrate that our model is a useful tool for exploring avenues for reducing the risks of light and heavy crude oil transportation across this region. The results we obtain indicate that a combined strategy of rail loading restrictions, pipeline deployments and a discontinuation of the oil export ban is most effective in reducing the transportation of crude oil by rail and thereby mitigating the associated risks.