Gas-Liquid Cylindrical Cyclone (GLCC©) Compact Separators For Wet Gas Applications

2003 ◽  
Vol 125 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Shoubo Wang ◽  
Luis E. Gomez ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
Gene E. Kouba
Keyword(s):  
Volume Fraction ◽  
Experimental Studies ◽  
Experimental Investigations ◽  
Liquid Droplets ◽  
Knock Out ◽  
Wet Gas ◽  
Cylindrical Cyclone ◽  
Carry Over ◽  
Operational Envelope ◽  
Gas Volume

Gas-Liquid Cylindrical Cyclone (GLCC©1) separators are becoming increasingly popular as attractive alternatives to conventional separators as they are simple, compact, less expensive, have low-weight, and require little maintenance. However, present studies focus on GLCC designs and applications at relatively lower gas velocities (below the minimum velocity for onset of liquid carry-over in the form of annular/mist flow). With appropriate modifications, GLCCs can be used for wet gas (high gas liquid ratio, GLR) applications, characterized by higher gas velocities, to knock out the liquid droplets from the gas core. The objectives of this study are to design a novel GLCC capable of separating liquid from a wet gas stream; conduct experimental investigations to evaluate the GLCC performance improvement in terms of operational envelope for liquid carry-over; and, quantify the liquid extraction from the gas stream. GLCC design considerations/guidelines for wet gas application are also provided based on the experimental studies at low pressures. This investigation extends the capabilities of compact separators for wet gas applications for insitu gas volume fraction (GVF) greater than 95%.

Gas-Liquid Cylindrical Cyclone (GLCC©) Compact Separators for Wet Gas Applications

2001 ◽  
Author(s):  
Shoubo Wang ◽  
Luis E. Gomez ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
Gene E. Kouba
Keyword(s):  
Experimental Studies ◽  
Design Guidelines ◽  
Experimental Investigations ◽  
Liquid Droplets ◽  
Knock Out ◽  
Wet Gas ◽  
Low Weight ◽  
Cylindrical Cyclone ◽  
Carry Over ◽  
Operational Envelope

Abstract Gas-Liquid Cylindrical Cyclone (GLCC©1) separators are becoming increasingly popular as attractive alternatives to conventional separators as they are simple, less expensive, have low-weight, and require little maintenance. However, present studies focus on GLCC designs and applications at relatively lower gas velocities (below the minimum velocity for onset of liquid carry-over in the form of mist flow). With appropriate modifications GLCCs can be used for wet gas and high gas oil ratio (GOR) applications, characterized by higher gas velocities, to knock out the liquid droplets from the gas core. The objectives of this study are to design a novel GLCC capable of separating liquid from a wet gas stream; conduct experimental investigations to evaluate the GLCC performance improvement in terms of operational envelope for liquid carryover; and, measure the liquid extraction from the gas stream. Specific design guidelines for wet gas GLCC are also formulated based on the experimental studies. This investigation provides new capabilities for compact separators for wet gas and high GOR (exceeding 90%) applications.

Wet Gas Separation in Gas-Liquid Cylindrical Cyclone (GLCC) Separator

2007 ◽  
Author(s):  
Robiro Molina ◽  
Shoubo Wang ◽  
Luis E. Gomez ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
...  
Keyword(s):  
High Pressure ◽  
Separation Efficiency ◽  
Mechanistic Model ◽  
Velocity Ratio ◽  
Wet Gas ◽  
Cylindrical Cyclone ◽  
Improved Performance ◽  
Carry Over ◽  
Operational Envelope ◽  
Annular Film

A novel Gas Liquid Cylindrical Cyclone (GLCC©), equipped with an Annular Film Extractor (AFE), for wet gas applications has been developed and studied experimentally and theoretically. Detailed experimental investigation of the modified GLCC has been carried out for low and high pressure conditions. The results show expansion of the operational envelope for liquid carry-over, and improved performance of the modified GLCC. For low pressures, the modified GLCC can remove all the liquid from the gas stream, resulting in zero liquid carry-over. For high pressure conditions, the GLCC with a single AFE has separation efficiency > 80% for gas velocity ratio of < 3. A mechanistic model and an aspect ratio design model for the modified GLCC has been developed, including the analysis of the AFE. The model predictions agree with the experimental data within ± 15% for low pressure and ± 25% for high pressure conditions.

Wet Gas Separation in Gas-Liquid Cylindrical Cyclone Separator

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Robiro Molina ◽  
Shoubo Wang ◽  
Luis E. Gomez ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
...  
Keyword(s):  
High Pressure ◽  
Separation Efficiency ◽  
Mechanistic Model ◽  
Velocity Ratio ◽  
Wet Gas ◽  
Cylindrical Cyclone ◽  
Improved Performance ◽  
Carry Over ◽  
Operational Envelope ◽  
Annular Film

A novel gas-liquid cylindrical cyclone (GLCC©, ©The University of Tulsa, 1994), equipped with an annular film extractor (AFE), for wet gas applications has been developed and studied experimentally and theoretically. Detailed experimental investigation of the modified GLCC has been carried out for low and high pressure conditions. The results show expansion of the operational envelope for liquid carry-over and improved performance of the modified GLCC. For low pressures, the modified GLCC can remove all the liquid from the gas stream, resulting in zero liquid carry-over (separation efficiency=100%). For high pressure conditions, the GLCC with a single AFE has separation efficiency >80% for gas velocity ratio, vsg/vann≤3. A mechanistic model and an aspect ratio design model for the modified GLCC have been developed, including the analysis of the AFE. The model predictions agree with the experimental data within ±15% for low pressure and ±25% for high pressure conditions.

Tangential Wall Jet Flow and Gas Entrainment in Gas-Liquid Cylindrical Cyclone Compact Separator

2019 ◽  
Author(s):  
Srinivas Swaroop Kolla ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Liquid Film ◽  
Mechanistic Model ◽  
Experimental Investigations ◽  
Wall Jet ◽  
Velocity Change ◽  
Gas Entrainment ◽  
Cylindrical Cyclone ◽  
Wall Jet Flow ◽  
Carry Over ◽  
Operational Envelope

Abstract Gas Carry-Under (GCU) is one of the undesirable phenomena that exist in the Gas-Liquid Cylindrical Cyclone (GLCC) separators even within the liquid carry-over Operational Envelope (OE). In order to quantify the GCU, it is important to understand the cause of gas entrainment that occurs in the GLCC other than the incoming entrained gas within the liquid medium. The tangential inclined inlet of 27° with reduced area allows the stratified liquid flow to exit the inlet nozzle tangentially along the wall into the vertical lower part of the GLCC, whereby the liquid film spreads along the wall in an asymmetrical shape. The gas moves to the center of the GLCC and escapes through the gas leg. The liquid film flow is complex and turbulent exhibiting unevenness of the film thickness and asymmetrical velocity distribution. Experimental investigations show that the magnitude of liquid wall jet film tangential and axial velocity change as a function of length along the GLCC below the inlet of the GLCC. This wall jet film flowing down along the wall is the cause for gas entrainment and GCU. The experimental results show that the gas entrainment mechanism is not like the conventional jet entrainment as expected to be occurring in GLCC. The change in velocities of the wall jet film at various liquid heights maintained below the inlet results in varying gas entrainment at various inlet liquid levels and for fluid properties. The wall jet phenomena that takes places at the inlet has been discussed in detail and a mechanistic model capable of predicting the wall jet parameters has been presented in this paper. Further, a novel mechanistic model that is developed for the first time is also presented which can predict the gas entrainment at various liquid levels and flow conditions using the wall jet parameters as an input condition.

scholarly journals A Review on the Application of Multiphase Twin Screw Pump as a Downhole Wet Gas Compressor to Improve Gas Wells Recovery Factor

2021 ◽  
Vol 15 ◽  
pp. 223-232
Author(s):  
Sharul Sham Dol ◽  
Niraj Baxi ◽  
Mior Azman Meor Said
Keyword(s):  
Volume Fraction ◽  
Energy Industry ◽  
Gas Wells ◽  
Screw Pump ◽  
Research Activities ◽  
Wet Gas ◽  
Gas Compression ◽  
Twin Screw ◽  
Gas Volume Fraction ◽  
Gas Volume

By introducing a multiphase twin screw pump as an artificial lifting device inside the well tubing (downhole) for wet gas compression application; i.e. gas volume fraction (GVF) higher than 95%, the unproductive or commercially unattractive gas wells can be revived and made commercially productive once again. Above strategy provides energy industry with an invaluable option to significantly reduce greenhouse gas emissions by reviving gas production from already existing infrastructure thereby reducing new exploratory and development efforts. At the same time above strategy enables energy industry to meet society’s demand for affordable energy throughout the critical energy transition from predominantly fossil fuels based resources to hybrid energy system of renewables and gas. This paper summarizes the research activities related to the applications involving multiphase twin screw pump for gas volume fraction (GVF) higher than 95% and outlines the opportunity that this new frontier of multiphase fluid research provides. By developing an understanding and quantifying the factors that influence volumetric efficiency of the multiphase twin screw pump, the novel concept of productivity improvement by a downhole wet gas compression using above technology can be made practicable and commercially more attractive than other production improvement strategies available today. Review and evaluation of the results of mathematical and experimental models for multiphase twin screw pump for applications with GVF of more than 95% has provided valuable insights in to multiphase physics in the gap leakage domains of pump and this increases confidence that novel theoretical concept of downhole wet gas compression using multiphase twin screw pump that is described in this paper, is practically achievable through further research and improvements.

A combined 2-D/1-D magma ascent model of explosive volcanic eruptions

2019 ◽  
Vol 219 (3) ◽  
pp. 1818-1835
Author(s):  
Hélène Massol
Keyword(s):  
Volume Fraction ◽  
Experimental Studies ◽  
Volcanic Eruptions ◽  
Gas Content ◽  
Magma Ascent ◽  
Explosive Eruptions ◽  
Shear Stresses ◽  
Order Of Magnitude ◽  
Gas Volume Fraction ◽  
Gas Volume

SUMMARY Explosive eruptions involve the fragmentation of magma that changes the flow regime from laminar to turbulent within the volcanic conduit during ascent. If the gas volume fraction is high, magma fragments and the eruption style is explosive, but if not, the magma flows effusively out of the vent. Gas escape processes depend on how the magma can rupture, and recent experimental studies measured rupture stress thresholds of the order of a few megapascals. It is thus critical to model the gas content and state of stress evolution in the flowing magma within the conduit. We present a new self-consistent model of an explosive eruption from the magma chamber to the surface, based on a critical gas volume fraction. Our model allows to explore irregular geometries below the fragmentation level (2-D). We first compare our model with classical 1-D models of explosive eruptions and find that in the case of straight conduits and fragmented flows, 1-D models are accurate enough to model the gas pressure and vertical velocity distribution in the conduit. However, in the case of an irregular conduit shape at depth, 2-D models are necessary. Despite a certain conduit radius visible at the surface, very different stress fields within the flow could be present depending upon the position and shape of any conduit irregularities. Stresses of the order of more than 1 MPa can be attained in some locations. High tensile stresses are located at the centre of the conduit, while high shear stresses are located at the conduit walls leading to several potential rupture locations. Due to the interplay between the velocity field and decompression rate, similar conduit radius visible at the surface might also lead to very different fragmentation depths with a difference of more than 1500 m between an enlarged conduit shape at some depth and a straight conduit. At depth, different conduit sizes might lead to the same order of magnitude for the mass flux, depending on the conduit geometry.

A Study on the Effect of Fluid Properties and Watercut on Liquid Carry-Over in Gas-Liquid Cylindrical Cyclone Compact Separators

2019 ◽  
Vol 141 (9) ◽  
Author(s):  
Srinivas Swaroop Kolla ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Heavy Oil ◽  
Limited Range ◽  
Level Control ◽  
Mineral Oils ◽  
Three Phase ◽  
Cylindrical Cyclone ◽  
Light Oil ◽  
Carry Over ◽  
Superficial Gas Velocity ◽  
Operational Envelope

Prediction of the operational envelope (OE-limited range of gas and liquid velocities) for liquid carry-over is essential for the optimized performance of gas-liquid cylindrical cyclone (GLCC©) compact separators. This study presents for the first time the operational envelop for three-phase gas-oil-water flow incorporating pressure and level control configurations. A series of experiments were conducted to evaluate the performance of a 3 in. diameter GLCC in terms of OE for liquid carry-over. Experiments were carried out at different watercuts ranging from 0% to 100% utilizing water and two different types of mineral oils namely: light oil and heavy oil with specific gravities of 0.859 and 0.937, respectively. The liquid level was controlled at 6 in. below the GLCC inlet for all the experimental flow conditions. The experimental results indicate that OE for liquid carry-over for three-phase flow is very sensitive to watercut. As the watercut reduces, the OE for liquid carry-over reduces monotonically. Also, the OE for heavy oil (indicated by higher viscosity) reduces as compared to light oil. The superficial gas velocity required to create an annular mist flow in the upper part of the GLCC increases with the increase of watercut and viscosity.

Performance Improvement of Gas Liquid Cylindrical Cyclone Separators Using Integrated Level and Pressure Control Systems

2000 ◽  
Vol 122 (4) ◽  
pp. 185-192 ◽  
Author(s):  
Shoubo Wang ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
Jack D. Marrelli ◽  
Gene E. Kouba
Keyword(s):  
Control System ◽  
Integrated Control ◽  
Control Valve ◽  
Pressure Control ◽  
Rate Region ◽  
Cylindrical Cyclone ◽  
Pressure Control System ◽  
Carry Over ◽  
Operational Envelope ◽  
Integrated Control System

The performance of gas-liquid cylindrical cyclone (GLCC©) separators for two-phase flow metering loop can be improved by eliminating liquid overflow into the gas leg or gas blow-out through the liquid leg, utilizing suitable integrated control systems. In this study, a new integrated control system has been developed for the GLCC, in which the control is achieved by a liquid control valve in the liquid discharge line and a gas control valve in the gas discharge line. Simulation studies demonstrate that the integrated level and pressure control system is highly desirable for slugging conditions. This strategy will enable the GLCC to operate at constant pressure so as not to restrict well flow and simultaneously prevent liquid carry-over and gas carry-under. Detailed experimental studies have been conducted to evaluate the improvement in the GLCC operational envelope for liquid carry-over with the integrated level and pressure control system. The results demonstrate that the GLCC equipped with integrated control system is capable of controlling the liquid level and GLCC pressure for a wide range of flow conditions. The experimental results also show that the operational envelope for liquid carry-over is improved twofold at higher liquid flow rate region and higher gas flow rate region. GLCC performance is also evaluated by measuring the operational envelope for onset of gas carry-under. [S0195-0738(00)00804-9]

scholarly journals Sintering of viscous droplets under surface tension

2016 ◽  
Vol 472 (2188) ◽  
pp. 20150780 ◽  
Author(s):  
Fabian B. Wadsworth ◽  
Jérémie Vasseur ◽  
Edward W. Llewellin ◽  
Jenny Schauroth ◽  
Katherine J. Dobson ◽  
...  
Keyword(s):  
Surface Tension ◽  
Volume Fraction ◽  
High Viscosity ◽  
Initial Distribution ◽  
Liquid Droplets ◽  
Free Standing ◽  
Gas Volume Fraction ◽  
Trapped Gas ◽  
Viscous Droplets ◽  
Gas Volume

We conduct experiments to investigate the sintering of high-viscosity liquid droplets. Free-standing cylinders of spherical glass beads are heated above their glass transition temperature, causing them to densify under surface tension. We determine the evolving volume of the bead pack at high spatial and temporal resolution. We use these data to test a range of existing models. We extend the models to account for the time-dependent droplet viscosity that results from non-isothermal conditions, and to account for non-zero final porosity. We also present a method to account for the initial distribution of radii of the pores interstitial to the liquid spheres, which allows the models to be used with no fitting parameters. We find a good agreement between the models and the data for times less than the capillary relaxation timescale. For longer times, we find an increasing discrepancy between the data and the model as the Darcy outgassing time-scale approaches the sintering timescale. We conclude that the decreasing permeability of the sintering system inhibits late-stage densification. Finally, we determine the residual, trapped gas volume fraction at equilibrium using X-ray computed tomography and compare this with theoretical values for the critical gas volume fraction in systems of overlapping spheres.

Swirling Flow Regimes and Gas Carry-Under in Gas–Liquid Cylindrical Cyclone Separator in a Separated Outlet Configuration

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Srinivas Swaroop Kolla ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Volume Fraction ◽  
Swirling Flow ◽  
Flow Behavior ◽  
Jet Impingement ◽  
Test Facility ◽  
Complex Flow ◽  
Cylindrical Cyclone ◽  
Oil Flow ◽  
Flow Mechanisms ◽  
Operational Envelope

Abstract Gas carry-under (GCU) and the corresponding gas volume fraction (GVF) in the gas–liquid cylindrical cyclone (GLCC©)2 liquid outlet occurs even within its normal operational envelope (OPEN). Few studies are available on GLCC, GCU, and GVF, which have been carried out in a GLCC operated in a metering loop configuration. This study focuses on GLCC GCU and GVF in swirling flow under separated outlet configuration with active control, which increases the GLCC OPEN significantly. A state-of-the-art test facility is used to acquire extensive GCU and GVF data for both air–water and air–oil flow in a 3″ diameter GLCC. The GLCC is equipped with three sequential trap sections to measure the instantaneous GVF and gas evolution in its lower part below the inlet. Also, gas trap sections are installed in the GLCC liquid outlet leg to measure the overall time-averaged GCU and GVF. The extensive acquired data shed light on the complex flow behavior in the lower part of the GLCC and its effect on the GCU and GVF in the GLCC. Tangential wall jet impingement from the GLCC inlet is the cause of gas entrainment and swirling in the lower GLCC body. The swirling flow mechanisms in the lower part of the GLCC are identified, which affect the GCU and GVF. The liquid viscosity and surface tension also affect the results. The GCU and GVF in the GLCC liquid outlet reduce as the superficial liquid velocities are increased for both air–oil and air–water flows, whereby the superficial gas velocities do not have a significant effect. The GCU and GVF for air–water flow are three orders of magnitude lower as compared to the air–oil flow.

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