Skip to main content

Harrison Osei

University Of Mines and Technology, Tarkwa, Petroleum Engineering, Faculty Member

Followers

2

Following

3

Public Views

Salaheldin Elkatatny

King Fahd University of Petroleum and Minerals

HUSNA HAYATI JARNI

University of Wolverhampton

King Fahd University of Petroleum and Minerals

Ahmed Abdelhafez

Abdul Haque Tunio

Mehran University of Engineering and Technology

mohammed elfadil

Interests

Uploads

Papers by Harrison Osei

Comparative Analysis of the Effect of Barite and Hematite on the Rheology of Water-Based Drilling Mud

High demand for oil and gas has led to exploration of more petroleum resources even at remote are... more High demand for oil and gas has led to exploration of more petroleum resources even at remote areas. The petroleum resources are found in deeper subsurface formations and drilling into such formations requires a well-designed drilling mud with suitable rheological properties in order to avoid or reduce associated drilling problems. This is because rheological properties of drilling muds have considerable effect on the drilling operation and cleaning of the wellbore. Mud engineers therefore use mud additives to influence the properties and functions of the drilling fluid to obtain the desired drilling mud properties especially rheological properties. This study investigated and compared the impact of barite and hematite as weighting agents for water-based drilling muds and their influence on the rheology. Water-based muds of different concentrations of weighting agents (5%, 10%, 15% and 20% of the total weight of the drilling mud) were prepared and their rheological properties determined at an ambient temperature of 24ᵒC to check their impact on drilling operation. The results found hematite to produce higher mud density, plastic viscosity, gel strength and yield point when compared to barite at the same weighting concentrations. The higher performance of the hematite-based muds might be attributed to it having higher specific gravity, better particle distribution and lower particle attrition rate and more importantly being free from contaminants. The water-based muds with hematite will therefore be more promising drilling muds with higher drilling and hole cleaning efficiency than those having barite.

Flow dynamics behaviour of a novel liquid-liquid hydrocyclone with varying upper cylindrical lengths and number of inlets

The use of a liquid-liquid hydrocyclone in the downhole is one the few environmentally friendly w... more The use of a liquid-liquid hydrocyclone in the downhole is one the few environmentally friendly ways by which water production can be limited, while at the same time ensure maximum recovery. The understanding of the fluid flow behaviours that bring about better separation and performance is therefore important and should not be underestimated. This work, through numerical simulation, studied the effects that the tangential inlet(s) and the height of the upper cylindrical section of a liquid-liquid hydrocyclone have on its hydrodynamics. The results showed that the single inlet hydrocyclones unlike the twin inlet types are more prone to producing asymmetrical reversal flow which meanders along the axis of the hydrocyclone. This can affect the efficiency of separation if the particles are not well segregated. The single inlet 30 mm upper cylindrical length (UCL) hydrocyclone produced the highest velocity fields that could ensure better fluid swirling and rotation, and the greatest upward core flowing pressure that could ensure better transportation of the lighter fraction concentrated at the core. Therefore, the single inlet hydrocyclone with 30 mm UCL is the best among the studied cyclonic separator types and its use for downhole oil/water separation can enhance the problem of excessive water production.

A review of optical flow models applied for fluid motion estimation

Fluid flow estimation from image sequences is a challenging due to the large and complex nature o... more Fluid flow estimation from image sequences is a challenging due to the large and complex nature of fluid flow. In this work, 36 papers on optical flow models applied for fluid motion estimation from 1980 to 2015 have been reviewed. The advantages and weaknesses of the optical flow models are discussed in detail. To improve the accuracy of the optical flow models, the principle of two multi-resolution schemes is discussed. The employment of higher order models provides more accurate motion vectors than the use of the standard optical flow model; however, it suffers from computational complexity. The use of the multi-resolution framework such as wavelet decomposition will reduce this complexity, as well as improve estimation accuracy.

A new approach for saturation height modelling in a clastic reservoir using response surface methodology and artificial neural network

Upstream Oil and Gas Technology

Model Investigation of Low Salinity Brine Injection on Gas-Condensate Recovery in a Sandstone Reservoir: Effect of Calcium and Sodium Ions

Zenodo (CERN European Organization for Nuclear Research), Sep 21, 2022

There are many technical challenges associated with the recovery of valuable condensates from gas... more There are many technical challenges associated with the recovery of valuable condensates from gas-condensate reservoirs. While some condensates are immobile far from the production well, others can accumulate close to the producer wellbore area. As a result, such valuable condensates are either not produced or, in some cases, their accumulation might choke the production well, lowering gas productivity. Maintaining reservoir pressure has long been a means of dealing with this problem. This, however, only functions as a temporary solution because the drop-out and immobile condensate production continues unabated. In this study, the effect of injecting brine into a gas-condensate reservoir at various concentrations was examined using a numerical simulation approach. It was found that changing two cations (Ca 2+ and Na +) concentrations could improve gas-condensate recovery at an injection rate of 490.8 m 3 /d (3000 bbl/d). According to this simulation research, the optimised range of sodium ion concentration fell between 0.013 and 0.026 mol/L, with 0.013 mol/L (300 ppm) being the optimum value. Additionally, the low salinity brine injection should have a Ca 2+ content greater than 0.0029 mol/L (116 ppm). It was also observed that changes in salinity had a negligible influence on gas recovery. Thus, if recovering lost condensate is of priority, then this recovery strategy is highly recommendable.

Enhanced machine learning tree classifiers for lithology identification using Bayesian optimization

Applied Computing and Geosciences

Biopolymer Drill-in Fluid Performance for Different Rheological Models using Statistical Characterisation

Ghana Mining Journal, Jun 30, 2019

Appropriate selection of rheological models is important for hydraulic calculations of pressure l... more Appropriate selection of rheological models is important for hydraulic calculations of pressure loss prediction and hole cleaning efficiency of drilling fluids. Power law, Bingham-Plastic and Herschel-Bulkley models are the conventional fluid models used in the oilfield. However, there are other models that have been proposed in literature which are under/or not utilized in the petroleum industry. The primary objective of this paper is to recommend a rheological model that best-fits the rheological behaviour of xanthan gum-based biopolymer drill-in fluids for hydraulic evaluations. Ten rheological models were evaluated in this study. These rheological models have been posed deterministically and due to the unrealistic nature have been replaced by statistical models, by adding an error (disturbance) term and making suitable assumptions about them. Rheological model parameters were estimated by least-square regression method. Models like Sisko and modified Sisko which are not conventional models in oil industry gave a good fit. Modified Sisko model which is a four parameter rheological model was selected as the best-fit model since it produced the least residual mean square of 0.61 Ibf 2 /100ft 4. There is 95% certainty that the true best-fit curve lies within the confidence band of this function of interest.

A comparative study on the hydrodynamics of liquid–liquid hydrocyclonic separation

The productivity of wells with a higher water-oil ratio can be improved by the use of a liquid-li... more The productivity of wells with a higher water-oil ratio can be improved by the use of a liquid-liquid hydrocyclone separator in the downhole. This system presents an excellent water flooding technique as the water separated downhole is pumped back into the same formation. The produced fluid undergoes a lot of orientations and motions from the time it enters the hydrocyclone until it exits the outlets. This paper helps bring to light the hydrodynamics of the liquid-liquid hydrocyclones, explaining how the fluid behaves once it is within the hydrocyclone, in order to achieve efficient separation. Analytical solutions were used to analyse some of the important flow pattern phenomenon within the liquid-liquid hydrocyclone. The fluid properties considered in this work are similar to that of the Malaysian Bayan offshore field. The results showed that the flow reversal radius was paramount in determining the separation efficiency. There were two existing swirling zones. In the inner zone the light fluid fraction is spiralling upwards, while in the outer zone the heavier fluid fraction is spiralling downward against the walls of the hydrocyclone.

Coconut oil and fermented palm wine biodiesel production for oil spill cleanup: experimental, numerical, and hybrid metaheuristic modeling approaches

Environmental Science and Pollution Research

Gas-liquid vertical pipe flow patterns convolutional neural network classification using experimental advanced wire mesh sensor images

Journal of Natural Gas Science and Engineering

Theoretical background and the flow fields in downhole liquid-liquid hydrocyclone (LLHC)

Abstract. Hydrocyclone system for downhole oil-water separation provides an effective technique o... more Abstract. Hydrocyclone system for downhole oil-water separation provides an effective technique of enhancing the economic viability of higher water-cut wells while at the same time reducing the risk of environmental pollution. This paper describes the hydrodynamics of the liquid-liquid hydrocyclones and the flow fields within it are paramount for achieving successful separation process. Some of the important hydrodynamic flow phenomenon within the liquid-liquid hydrocyclone and how they influence the separation efficiency of water/oil was analyzed through analytical solution. The properties of the liquids were based on Bayan offshore field measured properties. The results indicated that there are two swirling zones separated by stagnant flow field. The inner is the light liquid zone, while the outer is the heavy liquid zone. 1

Numerical studies on the separation performance of liquid- liquid Hydrocyclone for higher water-cut wells

IOP Conference Series: Materials Science and Engineering

Liquid-liquid hydrocyclones have nowadays become very useful in the oil industry because of their... more Liquid-liquid hydrocyclones have nowadays become very useful in the oil industry because of their numerous applications. They can be installed downhole in the case of a well that produces higher water-oil ratios. The design of a liquid-liquid hydrocyclone for such a task is critical and every geometric part of the hydrocyclone has a part to play as far as separation is concerned. This work, through validated numerical technique, investigated the liquid-liquid hydrocyclone performance for the cases of single-inlet and dual-inlets, with different upper cylindrical lengths, specifically, 30mm and 60mm.It was observed that the hydrocyclones with the 30mm upper cylindrical section perform better than the ones with 60 mm upper cylindrical section. It was again noted that, even though higher number of tangential inlets increases the swirl intensity, they have the tendency to break up the oil droplets within the hydrocyclone because of increasing shear and jet flow interaction.

A Review of the Rheological Effects of Power Law Drilling Fluids on Cuttings Transportation in Non-Vertical Boreholes

Experimental Study of a Hydrocyclonic Oil-Water Separator for Downhole Separation

This paper presents experimental measurement and analysis of a liquid-liquid hydrocyclone separat... more This paper presents experimental measurement and analysis of a liquid-liquid hydrocyclone separator to separate oil/water emulsion with 90% water cut. Measurements have been carried out at various temperatures and in-flow rates. Samples were taken before and after the separation and analyzed using InfraCal Oil/Grease Analyzer (HATR-T2). The results showed that, the hydrocyclone separator achieves separation efficiencies higher than 80%, in the flow split region between 0.6 – 0.7 for all the temperature cases considered in the experiments. Within inlet velocities range of 2.5 – 4.5 m/s, the hydrocyclone performance seems to plateau with separation efficiency remaining virtually constant for all the flow and temperature cases. The peak efficiencies for the cases at 25 o C, 30 o C, 40 o C, 50 o C and 60 o C temperatures were averagely around 80.9%, 84.1%, 85.9%, 86.5% and 87.5%, respectively. Fluid temperature slightly impacts the hydrocyclone separation performance. Separation efficie...

An Optical Flow Measurement Technique based on Continuous Wavelet Transform

Journal of Applied Fluid Mechanics, May 1, 2018

Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow ... more Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow dynamics. Oil jet flow associated with a multi-scale coherent structure in both space and time direction. Optical plume velocimetry (OPV) was developed by (Crone, McDuff, and Wilcock, 2008), and it was the most accurate technique that used for oil leak flow measurement. Despite its better estimation, the OPV measured the oil flow rate with high uncertainty of 21%. This is due to the multi-scale phenomena of oil flow, as well as the limited accuracy of direct cross correlation (DCC) typically used by OPV. This paper proposed a novel technique that considers the multi-scale property of turbulence in flow measurement. The proposed technique is based on continuous wavelet transform and estimates the flow using the following steps: Decomposition of turbulent flow signal by using continuous wavelet transform (CWT), correlation coefficient estimation in which Fast Fourier Transform (FFT) algorithm was used, interpolation and peak detection for the estimated correlation coefficients, and finally, the velocity field estimation. In order to validate the CWT-based technique, a turbulent buoyant jet, which has a similar flow-type of oil jet was experimentally simulated. Then, the CWT-based technique was applied to measure the jet flow, and the outcomes of the technique was compared to the experimental results. As a result, utilizing a smaller number of wavelet scales lead in better flow measurement as compared to the use of larger scales. CWT-based technique was accurately estimated the jet flow rate with standard error of 0.15 m/s, and outperformed the classical algorithms, including FFT, and DCC algorithms, which were measured with error of 3.65 m/s and 4.53 m/s respectively.

Rheological Effects of Power Law Drilling Fluids on Cuttings Transportation in Non-Vertical Wellbores

Proceedings of the first biennial UMaT International Conference on Mining & Mineral Processing, “Expanding the Frontiers of Mining Technology”, Tarkwa, Ghana, 4th – 7th August, 2010., 2010

Cuttings transportation in non-vertical boreholes is necessary for oil and gas wells. Efficient c... more Cuttings transportation in non-vertical boreholes is necessary for oil and gas wells. Efficient cuttings removal from a wellbore during drilling is critical for cost-effective drilling as high annular cuttings buildup often leads to high risk of stuck pipe, reduced rate of penetration and other impediments to standard drilling and completion procedures. This study investigates rheological parameters influence on the removal of cuttings in non-vertical boreholes in the course of drilling. In this study, twelve mud samples with density ranging from 8.45 – 8.50 were selected to study the rheological parameters at three different annular velocities (1.91, 2.86 and 3.82 ft/sec) and three hole angles (30 o , 45 o and 70 o ) from vertical. A programme was developed using excel spreadsheet which could determine the rheological parameters and their effect on cuttings removal from non-vertical boreholes. Results showed that better sweep of drilled cuttings is favoured by increasing annular ve...

Time Delay Estimation Using Continuous Wavelet Transform Coefficients

Advanced Science Letters

An Optical Flow Measurement Technique based on Continuous Wavelet Transform

Journal of Applied Fluid Mechanics

Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow ... more Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow dynamics. Oil jet flow associated with a multi-scale coherent structure in both space and time direction. Optical plume velocimetry (OPV) was developed by (Crone, McDuff, and Wilcock, 2008), and it was the most accurate technique that used for oil leak flow measurement. Despite its better estimation, the OPV measured the oil flow rate with high uncertainty of 21%. This is due to the multi-scale phenomena of oil flow, as well as the limited accuracy of direct cross correlation (DCC) typically used by OPV. This paper proposed a novel technique that considers the multi-scale property of turbulence in flow measurement. The proposed technique is based on continuous wavelet transform and estimates the flow using the following steps: Decomposition of turbulent flow signal by using continuous wavelet transform (CWT), correlation coefficient estimation in which Fast Fourier Transform (FFT) algorithm was used, interpolation and peak detection for the estimated correlation coefficients, and finally, the velocity field estimation. In order to validate the CWT-based technique, a turbulent buoyant jet, which has a similar flow-type of oil jet was experimentally simulated. Then, the CWT-based technique was applied to measure the jet flow, and the outcomes of the technique was compared to the experimental results. As a result, utilizing a smaller number of wavelet scales lead in better flow measurement as compared to the use of larger scales. CWT-based technique was accurately estimated the jet flow rate with standard error of 0.15 m/s, and outperformed the classical algorithms, including FFT, and DCC algorithms, which were measured with error of 3.65 m/s and 4.53 m/s respectively.

A comparative study on the hydrodynamics of liquid–liquid hydrocyclonic separation

ABSTRACT

Flow structures and their impact on single and dual inlets hydrocyclone performance for oil–water separation

Journal of Petroleum Exploration and Production Technology

With many of today's oil wells located offshore, the production of high volumes of water compared... more With many of today's oil wells located offshore, the production of high volumes of water compared to oil poses major challenges to oil operators. The use of liquid-liquid hydrocyclone (LLHC) is one effective way to arrest these uphill problems of produced water. However, the nature of fluid flow within the LLHC device is very vital to the separation process and performance. This study through numerical simulation lends understanding to the way oil-water fluid migrates within LLHC device and shows how the flow structure can affect the efficiency of the separation process. Unsteady wavering flow was realized for the use of the single inlet due to flow imbalance just after entry into the cyclone. This affected the efficiency of separation as water droplets in the vicinity of the reverse flow core boundary could be carried to the overflow. In addition, there was the realization of frequent recirculation zones which cause some fluid droplets to be unseparated. Uniform unwavering fluid flow structure was observed in the case of dual inlet LLHC which assisted in the segregation of the oil and water into their respective core regions as oil-rich core (inner) and water-rich core (outer). The separation efficiency achieved from the use of the dual inlet LLHC outperformed that from the single inlet LLHC. An efficiency of 82.3% was obtained for the dual inlet LLHC as against 73.7% for the single inlet LLHC at 0.5 m 3 /h. At 1.0 m 3 /h, a great separation performance of 93.6% was achieved from the dual inlet LLHC, whereas separation efficiency of 88.5% was obtained when the same feed was treated in the single inlet LLHC.

Comparative Analysis of the Effect of Barite and Hematite on the Rheology of Water-Based Drilling Mud

High demand for oil and gas has led to exploration of more petroleum resources even at remote are... more High demand for oil and gas has led to exploration of more petroleum resources even at remote areas. The petroleum resources are found in deeper subsurface formations and drilling into such formations requires a well-designed drilling mud with suitable rheological properties in order to avoid or reduce associated drilling problems. This is because rheological properties of drilling muds have considerable effect on the drilling operation and cleaning of the wellbore. Mud engineers therefore use mud additives to influence the properties and functions of the drilling fluid to obtain the desired drilling mud properties especially rheological properties. This study investigated and compared the impact of barite and hematite as weighting agents for water-based drilling muds and their influence on the rheology. Water-based muds of different concentrations of weighting agents (5%, 10%, 15% and 20% of the total weight of the drilling mud) were prepared and their rheological properties determined at an ambient temperature of 24ᵒC to check their impact on drilling operation. The results found hematite to produce higher mud density, plastic viscosity, gel strength and yield point when compared to barite at the same weighting concentrations. The higher performance of the hematite-based muds might be attributed to it having higher specific gravity, better particle distribution and lower particle attrition rate and more importantly being free from contaminants. The water-based muds with hematite will therefore be more promising drilling muds with higher drilling and hole cleaning efficiency than those having barite.

Flow dynamics behaviour of a novel liquid-liquid hydrocyclone with varying upper cylindrical lengths and number of inlets

The use of a liquid-liquid hydrocyclone in the downhole is one the few environmentally friendly w... more The use of a liquid-liquid hydrocyclone in the downhole is one the few environmentally friendly ways by which water production can be limited, while at the same time ensure maximum recovery. The understanding of the fluid flow behaviours that bring about better separation and performance is therefore important and should not be underestimated. This work, through numerical simulation, studied the effects that the tangential inlet(s) and the height of the upper cylindrical section of a liquid-liquid hydrocyclone have on its hydrodynamics. The results showed that the single inlet hydrocyclones unlike the twin inlet types are more prone to producing asymmetrical reversal flow which meanders along the axis of the hydrocyclone. This can affect the efficiency of separation if the particles are not well segregated. The single inlet 30 mm upper cylindrical length (UCL) hydrocyclone produced the highest velocity fields that could ensure better fluid swirling and rotation, and the greatest upward core flowing pressure that could ensure better transportation of the lighter fraction concentrated at the core. Therefore, the single inlet hydrocyclone with 30 mm UCL is the best among the studied cyclonic separator types and its use for downhole oil/water separation can enhance the problem of excessive water production.

A review of optical flow models applied for fluid motion estimation

Fluid flow estimation from image sequences is a challenging due to the large and complex nature o... more Fluid flow estimation from image sequences is a challenging due to the large and complex nature of fluid flow. In this work, 36 papers on optical flow models applied for fluid motion estimation from 1980 to 2015 have been reviewed. The advantages and weaknesses of the optical flow models are discussed in detail. To improve the accuracy of the optical flow models, the principle of two multi-resolution schemes is discussed. The employment of higher order models provides more accurate motion vectors than the use of the standard optical flow model; however, it suffers from computational complexity. The use of the multi-resolution framework such as wavelet decomposition will reduce this complexity, as well as improve estimation accuracy.

A new approach for saturation height modelling in a clastic reservoir using response surface methodology and artificial neural network

Upstream Oil and Gas Technology

Model Investigation of Low Salinity Brine Injection on Gas-Condensate Recovery in a Sandstone Reservoir: Effect of Calcium and Sodium Ions

Zenodo (CERN European Organization for Nuclear Research), Sep 21, 2022

There are many technical challenges associated with the recovery of valuable condensates from gas... more There are many technical challenges associated with the recovery of valuable condensates from gas-condensate reservoirs. While some condensates are immobile far from the production well, others can accumulate close to the producer wellbore area. As a result, such valuable condensates are either not produced or, in some cases, their accumulation might choke the production well, lowering gas productivity. Maintaining reservoir pressure has long been a means of dealing with this problem. This, however, only functions as a temporary solution because the drop-out and immobile condensate production continues unabated. In this study, the effect of injecting brine into a gas-condensate reservoir at various concentrations was examined using a numerical simulation approach. It was found that changing two cations (Ca 2+ and Na +) concentrations could improve gas-condensate recovery at an injection rate of 490.8 m 3 /d (3000 bbl/d). According to this simulation research, the optimised range of sodium ion concentration fell between 0.013 and 0.026 mol/L, with 0.013 mol/L (300 ppm) being the optimum value. Additionally, the low salinity brine injection should have a Ca 2+ content greater than 0.0029 mol/L (116 ppm). It was also observed that changes in salinity had a negligible influence on gas recovery. Thus, if recovering lost condensate is of priority, then this recovery strategy is highly recommendable.

Enhanced machine learning tree classifiers for lithology identification using Bayesian optimization

Applied Computing and Geosciences

Biopolymer Drill-in Fluid Performance for Different Rheological Models using Statistical Characterisation

Ghana Mining Journal, Jun 30, 2019

Appropriate selection of rheological models is important for hydraulic calculations of pressure l... more Appropriate selection of rheological models is important for hydraulic calculations of pressure loss prediction and hole cleaning efficiency of drilling fluids. Power law, Bingham-Plastic and Herschel-Bulkley models are the conventional fluid models used in the oilfield. However, there are other models that have been proposed in literature which are under/or not utilized in the petroleum industry. The primary objective of this paper is to recommend a rheological model that best-fits the rheological behaviour of xanthan gum-based biopolymer drill-in fluids for hydraulic evaluations. Ten rheological models were evaluated in this study. These rheological models have been posed deterministically and due to the unrealistic nature have been replaced by statistical models, by adding an error (disturbance) term and making suitable assumptions about them. Rheological model parameters were estimated by least-square regression method. Models like Sisko and modified Sisko which are not conventional models in oil industry gave a good fit. Modified Sisko model which is a four parameter rheological model was selected as the best-fit model since it produced the least residual mean square of 0.61 Ibf 2 /100ft 4. There is 95% certainty that the true best-fit curve lies within the confidence band of this function of interest.

A comparative study on the hydrodynamics of liquid–liquid hydrocyclonic separation

The productivity of wells with a higher water-oil ratio can be improved by the use of a liquid-li... more The productivity of wells with a higher water-oil ratio can be improved by the use of a liquid-liquid hydrocyclone separator in the downhole. This system presents an excellent water flooding technique as the water separated downhole is pumped back into the same formation. The produced fluid undergoes a lot of orientations and motions from the time it enters the hydrocyclone until it exits the outlets. This paper helps bring to light the hydrodynamics of the liquid-liquid hydrocyclones, explaining how the fluid behaves once it is within the hydrocyclone, in order to achieve efficient separation. Analytical solutions were used to analyse some of the important flow pattern phenomenon within the liquid-liquid hydrocyclone. The fluid properties considered in this work are similar to that of the Malaysian Bayan offshore field. The results showed that the flow reversal radius was paramount in determining the separation efficiency. There were two existing swirling zones. In the inner zone the light fluid fraction is spiralling upwards, while in the outer zone the heavier fluid fraction is spiralling downward against the walls of the hydrocyclone.

Coconut oil and fermented palm wine biodiesel production for oil spill cleanup: experimental, numerical, and hybrid metaheuristic modeling approaches

Environmental Science and Pollution Research

Gas-liquid vertical pipe flow patterns convolutional neural network classification using experimental advanced wire mesh sensor images

Journal of Natural Gas Science and Engineering

Theoretical background and the flow fields in downhole liquid-liquid hydrocyclone (LLHC)

Abstract. Hydrocyclone system for downhole oil-water separation provides an effective technique o... more Abstract. Hydrocyclone system for downhole oil-water separation provides an effective technique of enhancing the economic viability of higher water-cut wells while at the same time reducing the risk of environmental pollution. This paper describes the hydrodynamics of the liquid-liquid hydrocyclones and the flow fields within it are paramount for achieving successful separation process. Some of the important hydrodynamic flow phenomenon within the liquid-liquid hydrocyclone and how they influence the separation efficiency of water/oil was analyzed through analytical solution. The properties of the liquids were based on Bayan offshore field measured properties. The results indicated that there are two swirling zones separated by stagnant flow field. The inner is the light liquid zone, while the outer is the heavy liquid zone. 1

Numerical studies on the separation performance of liquid- liquid Hydrocyclone for higher water-cut wells

IOP Conference Series: Materials Science and Engineering

Liquid-liquid hydrocyclones have nowadays become very useful in the oil industry because of their... more Liquid-liquid hydrocyclones have nowadays become very useful in the oil industry because of their numerous applications. They can be installed downhole in the case of a well that produces higher water-oil ratios. The design of a liquid-liquid hydrocyclone for such a task is critical and every geometric part of the hydrocyclone has a part to play as far as separation is concerned. This work, through validated numerical technique, investigated the liquid-liquid hydrocyclone performance for the cases of single-inlet and dual-inlets, with different upper cylindrical lengths, specifically, 30mm and 60mm.It was observed that the hydrocyclones with the 30mm upper cylindrical section perform better than the ones with 60 mm upper cylindrical section. It was again noted that, even though higher number of tangential inlets increases the swirl intensity, they have the tendency to break up the oil droplets within the hydrocyclone because of increasing shear and jet flow interaction.

A Review of the Rheological Effects of Power Law Drilling Fluids on Cuttings Transportation in Non-Vertical Boreholes

Experimental Study of a Hydrocyclonic Oil-Water Separator for Downhole Separation

This paper presents experimental measurement and analysis of a liquid-liquid hydrocyclone separat... more This paper presents experimental measurement and analysis of a liquid-liquid hydrocyclone separator to separate oil/water emulsion with 90% water cut. Measurements have been carried out at various temperatures and in-flow rates. Samples were taken before and after the separation and analyzed using InfraCal Oil/Grease Analyzer (HATR-T2). The results showed that, the hydrocyclone separator achieves separation efficiencies higher than 80%, in the flow split region between 0.6 – 0.7 for all the temperature cases considered in the experiments. Within inlet velocities range of 2.5 – 4.5 m/s, the hydrocyclone performance seems to plateau with separation efficiency remaining virtually constant for all the flow and temperature cases. The peak efficiencies for the cases at 25 o C, 30 o C, 40 o C, 50 o C and 60 o C temperatures were averagely around 80.9%, 84.1%, 85.9%, 86.5% and 87.5%, respectively. Fluid temperature slightly impacts the hydrocyclone separation performance. Separation efficie...

An Optical Flow Measurement Technique based on Continuous Wavelet Transform

Journal of Applied Fluid Mechanics, May 1, 2018

Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow ... more Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow dynamics. Oil jet flow associated with a multi-scale coherent structure in both space and time direction. Optical plume velocimetry (OPV) was developed by (Crone, McDuff, and Wilcock, 2008), and it was the most accurate technique that used for oil leak flow measurement. Despite its better estimation, the OPV measured the oil flow rate with high uncertainty of 21%. This is due to the multi-scale phenomena of oil flow, as well as the limited accuracy of direct cross correlation (DCC) typically used by OPV. This paper proposed a novel technique that considers the multi-scale property of turbulence in flow measurement. The proposed technique is based on continuous wavelet transform and estimates the flow using the following steps: Decomposition of turbulent flow signal by using continuous wavelet transform (CWT), correlation coefficient estimation in which Fast Fourier Transform (FFT) algorithm was used, interpolation and peak detection for the estimated correlation coefficients, and finally, the velocity field estimation. In order to validate the CWT-based technique, a turbulent buoyant jet, which has a similar flow-type of oil jet was experimentally simulated. Then, the CWT-based technique was applied to measure the jet flow, and the outcomes of the technique was compared to the experimental results. As a result, utilizing a smaller number of wavelet scales lead in better flow measurement as compared to the use of larger scales. CWT-based technique was accurately estimated the jet flow rate with standard error of 0.15 m/s, and outperformed the classical algorithms, including FFT, and DCC algorithms, which were measured with error of 3.65 m/s and 4.53 m/s respectively.

Rheological Effects of Power Law Drilling Fluids on Cuttings Transportation in Non-Vertical Wellbores

Proceedings of the first biennial UMaT International Conference on Mining & Mineral Processing, “Expanding the Frontiers of Mining Technology”, Tarkwa, Ghana, 4th – 7th August, 2010., 2010

Cuttings transportation in non-vertical boreholes is necessary for oil and gas wells. Efficient c... more Cuttings transportation in non-vertical boreholes is necessary for oil and gas wells. Efficient cuttings removal from a wellbore during drilling is critical for cost-effective drilling as high annular cuttings buildup often leads to high risk of stuck pipe, reduced rate of penetration and other impediments to standard drilling and completion procedures. This study investigates rheological parameters influence on the removal of cuttings in non-vertical boreholes in the course of drilling. In this study, twelve mud samples with density ranging from 8.45 – 8.50 were selected to study the rheological parameters at three different annular velocities (1.91, 2.86 and 3.82 ft/sec) and three hole angles (30 o , 45 o and 70 o ) from vertical. A programme was developed using excel spreadsheet which could determine the rheological parameters and their effect on cuttings removal from non-vertical boreholes. Results showed that better sweep of drilled cuttings is favoured by increasing annular ve...

Time Delay Estimation Using Continuous Wavelet Transform Coefficients

Advanced Science Letters

An Optical Flow Measurement Technique based on Continuous Wavelet Transform

Journal of Applied Fluid Mechanics

Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow ... more Flow measurement underwater oil leak is a challenging problem, due to the complex nature of flow dynamics. Oil jet flow associated with a multi-scale coherent structure in both space and time direction. Optical plume velocimetry (OPV) was developed by (Crone, McDuff, and Wilcock, 2008), and it was the most accurate technique that used for oil leak flow measurement. Despite its better estimation, the OPV measured the oil flow rate with high uncertainty of 21%. This is due to the multi-scale phenomena of oil flow, as well as the limited accuracy of direct cross correlation (DCC) typically used by OPV. This paper proposed a novel technique that considers the multi-scale property of turbulence in flow measurement. The proposed technique is based on continuous wavelet transform and estimates the flow using the following steps: Decomposition of turbulent flow signal by using continuous wavelet transform (CWT), correlation coefficient estimation in which Fast Fourier Transform (FFT) algorithm was used, interpolation and peak detection for the estimated correlation coefficients, and finally, the velocity field estimation. In order to validate the CWT-based technique, a turbulent buoyant jet, which has a similar flow-type of oil jet was experimentally simulated. Then, the CWT-based technique was applied to measure the jet flow, and the outcomes of the technique was compared to the experimental results. As a result, utilizing a smaller number of wavelet scales lead in better flow measurement as compared to the use of larger scales. CWT-based technique was accurately estimated the jet flow rate with standard error of 0.15 m/s, and outperformed the classical algorithms, including FFT, and DCC algorithms, which were measured with error of 3.65 m/s and 4.53 m/s respectively.

A comparative study on the hydrodynamics of liquid–liquid hydrocyclonic separation

ABSTRACT

Flow structures and their impact on single and dual inlets hydrocyclone performance for oil–water separation

Journal of Petroleum Exploration and Production Technology

With many of today's oil wells located offshore, the production of high volumes of water compared... more With many of today's oil wells located offshore, the production of high volumes of water compared to oil poses major challenges to oil operators. The use of liquid-liquid hydrocyclone (LLHC) is one effective way to arrest these uphill problems of produced water. However, the nature of fluid flow within the LLHC device is very vital to the separation process and performance. This study through numerical simulation lends understanding to the way oil-water fluid migrates within LLHC device and shows how the flow structure can affect the efficiency of the separation process. Unsteady wavering flow was realized for the use of the single inlet due to flow imbalance just after entry into the cyclone. This affected the efficiency of separation as water droplets in the vicinity of the reverse flow core boundary could be carried to the overflow. In addition, there was the realization of frequent recirculation zones which cause some fluid droplets to be unseparated. Uniform unwavering fluid flow structure was observed in the case of dual inlet LLHC which assisted in the segregation of the oil and water into their respective core regions as oil-rich core (inner) and water-rich core (outer). The separation efficiency achieved from the use of the dual inlet LLHC outperformed that from the single inlet LLHC. An efficiency of 82.3% was obtained for the dual inlet LLHC as against 73.7% for the single inlet LLHC at 0.5 m 3 /h. At 1.0 m 3 /h, a great separation performance of 93.6% was achieved from the dual inlet LLHC, whereas separation efficiency of 88.5% was obtained when the same feed was treated in the single inlet LLHC.