Horizontal Separators Research Articles

Liquid carry-over control using three-phase horizontal smart separators in Khor Mor gas-condensate processing plant

Liquid carry-over phenomenon, where liquid droplets escape with gas, is a prevalent operational challenge in gas–liquid separators. Liquid carry-over leads to foaming issue and performance reduction within separator downstream absorption processes. In order to ascertain whether liquid carry-over is inducing foaming within the gas sweetening process’s absorption tower at Iraq’s Khor Mor gas-condensate processing plant, this study initiated an evaluation of the liquid droplet size distribution in the gas product and gas/liquid separation efficiency of upstream Alpha, Bravo #1, Bravo #2, and Charlee separators that feed into the aforementioned tower by using the Horizontal Vessel and ProSeparator correlations in Aspen HYSYS v.11 software. The study revealed that Alpha and Bravo #2 experienced liquid carry-over issues. In response to these challenges, an innovative smart separator design, referred to as an adjustable separator, was proposed, employing the Arnold-Stewart semi-empirical procedure. This design allows for easy adjustment to accommodate changes in feed composition and operational conditions, mitigating the liquid carry-over problem. The smart design demonstrated a significant increase in gas/liquid separation efficiency for Alpha separator, improving by 31.11% under current conditions and 77.65% under future conditions. Similarly, under both current and future conditions, the smart design of Bravo #2 separator yielded an enhancement of 21.31% and 28.23%, respectively. These results suggest that the smart design can be considered an optimal solution for controlling liquid carry-over. This innovation not only maintains high gas/liquid separation efficiency but also prevents foaming, offering a robust solution for ensuring sustained operational performance and productivity in gas–liquid separation processes.

The effects of the separator structures and magnetic roller arrangements on eddy current separation

The eddy current separator is the key equipment used for the separation and enrichment of non-ferrous metals from the solid waste. The customization and universality requirements for eddy current separators have been improved with the increasingly strict environmental protection requirements in various industries and the pursuit of higher economic benefits by enterprises. The low separation efficiency of the small-sized non-ferrous metals and the difficulty in separating between non-ferrous metals are two urgent problems that limit the development of the eddy current separation. The separator structures design, the factors regulation and the core component magnetic roller optimization are the keys to solve problems. Vertical and horizontal eddy current separators are the two main types of permanent magnet eddy current separators in practical applications and reported studies. However, the study and production cost of the eddy current separator are high, and there are few reports on the separator structures in existing studies. There is also a lack of comparative analysis of different applicable conditions for eddy current separators and optimization design of the magnetic roller. This study compared and analyzed the effects of different factors on the vertical and horizontal eddy current separation efficiency, and clarified the advantages and prospects of the vertical eddy current separator in optimizing the separation efficiency between non-ferrous metals. The comparison and multi-objective optimization were conducted on the magnetic rollers to expand the particle size range that can be separated. The separation performance and the economy of the magnetic roller have been improved significantly, and the performance indicators are better than those of existing equipment with the same specifications. The magnetic roller with specific structural parameters has increased eddy current force and magnetic efficiency density by 75.0% and 63.5%, respectively. It is expected to further expand the applicable materials for the eddy current separator.

Dynamic Modelling and Simulation of A Three-Phase Gravity Separator

Many studies have investigated the crude oil separation process’s separation mechanisms, size, and design, employing horizontal 3-Phase Gravity Separators in depth. There are, however, very few articles on their dynamics, modelling, and simulation. Understanding its dynamic behaviour will aid in designing and tuning the device that can manage water level, oil level, and gas pressure in response to feeding variations. This Scientific Paper gives a complete mathematical analysis, modelling, and simulation of a crude oil separation process using a horizontal 3-Phase Gravity Separator using Mathworks Matlab R2016b-x64 and Aspen Hysys V10. Bishoy’s Equations, which were constructed, will assist in operating this gadget, locating various variables, and observing the effect of modifying variables on the system’s variables. The rationale for this study was developed in response to the small number of articles discovered, which may be a covert issue held up by large oil companies, as well as the complicated equations related to this process that remain unsolved, and to monitor what is happening in this complex dynamic process. As a result, this Research Paper is unique and novel, and it can be compared to the work done by some authors who did not solve the obtained differential equations and did not go further in Aspen Hysys Modeling and Simulation, whereas this paper provides everything related to a three-phase gravity separator, including changing of variables and observing the effect on the system when those variables were modified. Furthermore, separators are designed with internal baffles to promote laminar flow and increase separator efficiency. However, it has been assumed that there are no baffles here, which is a significant problem, but with the help of these equations, the horizontal three-phase gravity separator can be operated at its maximum efficiency. The equations determined the following variables: The height of gas, water, oil, the height of oil when it jumped the weir, the pressure of the gas (in and out), water pressure (in and out), oil pressure (in and out), and the effect of increasing (control valve’s stem position) and decreasing Qin (inlet volumetric flowrate) on these variables have all been studied. This article discovered that increasing the control valve stem position and decreasing the inflow volumetric flowrate of both oil and water was highly unsafe and caused significant variations in the system’s heights and pressures using Matlab. The Aspen Hysys analysis optimally separates the oil, gas, and water to determine material, energy streams properties, and compositions. As a result, this complex dynamic behaviour was observed, and no additional articles were discovered that addressed this subject. This process monitoring will determine the best conditions for flawless separation, with the selectivity of the desired product or products as the primary goal. This research can revolutionize the way people think about oil and gas extraction and processing and benefit colossal oil and gas firms in Europe, Asia, and Africa.

Improving the Dust Removal Efficiency of a Natural Gas Filter: An Experimental and Numerical Simulation Study.

This study aims to evaluate the dust removal efficiency and working conditions of a filter separator through a pressure drop under various operating conditions. Typical horizontal filter separators in natural gas stations were taken as the research objects, and the computational fluid dynamics method was first attempted to investigate the static and dynamic characteristics of the pressure drop and the dust removal efficiency under different operating times and pressures. Then, the simulated results were compared with those obtained from online dust detection. At a constant standard flow rate, the detected pressure drop deviated from the fitted optimal quadratic curve with an increase in the operation duration of the filter separator, and the dust removal efficiency also tended to decline. The declining trend was particularly faster at lower operating pressures caused by the fast air flow, which leads to more coalesced particles flowing out and increases the dust concentration downstream. A higher initial pressure drop of the filter separator was also maintained at a low operating pressure. The dust removal efficiency rapidly decreased at a higher throughput load, and the decreasing rate became moderate at a lower input load. An optimum operating throughput of the filter was obtained when the input load varied in the range of 100 × 104-270 × 104 Nm3/d. Good agreement was achieved between the simulated and experimental dust removal efficiency, and the relative errors are within ±20%. Both methods applied in this work were verified to have high accuracy and reliability through the actual on-site amount of dust captured.

Hydrodynamics of vapor-liquid flows in curvilined channels of separation devices of power plants

The main factor that affects the efficiency of the separation process is the lack of contact with the surface of the shutter when moving in the flow of small droplets of wet steam. This process depends on the physical and chemical properties of the wet vapor, the dispersion of the droplets, the parameters of the movement of the two-phase medium, adhesion and edge angle, and the geometry of the channel. Purpose. Determination of the limit modes of operation of separation shutter devices depending on the dispersion and quantity of droplet liquid, flow parameters and geometric characteristics of curved channels. Methodology. The methodology is based on the analysis of the physical model of the movement of a two-phase medium under the action of mass and gravitational forces in a curved horizontal channel. Findings. A mathematical model is presented for determining the trajectory of a liquid droplet in a curvilinear corrugation channel of the louvered package of a separator-superheater. The main conditions of film destruction and dynamic droplet break-up are defined. A method for expanding the range of stable operation of separation devices is proposed. Based on the obtained correlations, the design of the blind package is optimized. Originality. Based on the analysis of the physical model of the movement of a two-phase medium in a curved horizontal channel, a mathematical model was developed and the limit of capture of the dispersed phase was determined. Practical value. The presented results allow optimization of separation devices of boiler drums, horizontal steam generators and steam superheater separators of the II circuit of VVER-1000, fuel preparation systems of GTU.

Investigation of particle capture by grooved plates with elliptic teeth for high intensity magnetic separation

Horizontal ring high intensity magnetic separators adopting grooved plates with right angle teeth present superiority on recovering ultrafine weakly magnetic materials. Being limited by saturation magnetization of magnetic iron yoke, optimizing magnetic field characteristics of grooved plates is a potential way for further improving separation efficiency. In this study, elliptic teeth were designed and optimized for grooved plates in horizontal ring separators. Magnetic field characteristics and particle capture performance of elliptic teeth plates were investigated and compared with conventional plates theoretically and experimentally. Magnetic field force and particle capture cross section area of elliptic teeth plates increased with increasing aspect ratio. Elliptic teeth plates with aspect ratio λ > 1.5 presented larger high magnetic field force region and particle capture cross section area than conventional plates. Particle capture experiments with pure and actual hematite ore indicated that elliptic teeth plates with aspect ratio of 2 and 3 had better particle capture performance and separation efficiency than conventional plates, which was in consistence with theoretical analyses. Elliptic teeth plates presented better magnetic field characteristics and had good application prospect in horizontal ring high intensity magnetic separators.

Research on the Gas-Liquid Two-Phase Distribution Behavior and Influencing Factors of Swirling Flow in Horizontal Pipe

Gas-liquid two-phase swirling flow is widely used for gas-liquid separation in the power, chemical, petroleum, and nuclear industries. However, the majority of current research on swirling flow focuses on identifying flow patterns and does not pay more attention to topics such as the boundary where swirling flow forms. The length and diameter of the central gas core are the main focus of the current studies as well as the distribution patterns of gas-liquid two-phase. Comparative studies on the gas-liquid distribution morphology, such as whether the gas phase is separated and the separation mode, are lacking. In this paper, a combination of visual experimental observations and numerical simulations of Computational Fluid Dynamics (CFD) is used to investigate the formation conditions of gas-liquid two-phase swirling flow in three types of cyclonic components. The results show that the minimum superficial liquid velocity for the formation of swirling flow in the horizontal tube is about 0.375~0.82 m/s when the superficial gas velocity is less than 10 m/s. The formation of swirling flow is almost independent of the geometric swirl number and superficial liquid velocity when the superficial gas velocity is greater than 10 m/s. At low inlet superficial velocities, the tangential velocity determines the transition from swirling flow to stratified flow. However, at higher inlet superficial velocities, the decay of the cyclonic field is mainly affected by the wave amplitude of the gas-liquid interface. In both co-current and counter-current horizontal inline gas-liquid cyclone separators, the flow split is related to the vortex core breakdown of the central gas core. In addition, the numerical simulation results show that the breakdown of the vortex core is related to the pressure distribution inside the separator. This work enriches the study of swirling flow and provides a basis for the performance improvement of inline gas-liquid cyclone separators.

Sand settling in a three-phase flow inside a horizontal separator

Sand particles in multiphase flows have been a major problem in the oil and gas industry, with many recent reports of failures in equipment due to erosion from solid particles. Horizontal separators have proven to be one of the most effective methods for sand removal especially the design developed by Specialized Desanders Inc., this study will analyze the sand separation in a three-phase flow from two angles. First, by applying multiphase numerical analysis using Star CCM+ software. Experimental testing with the three-phase flow (air, water, and sand) was performed and compared to the numerical results. Both the experimental and the simulation results have shown that 99% of sand has settled within 54% of the Desander length. Second, an analytical model was also performed to analyze the forces acting on the sand particles ( d = 150 µm and 300 µm) in a simplified matter to solve particle equations of motion in each phase the particle transits. The analytical model showed both particle sizes did not reach terminal velocity in the gas phase. Both particles reached terminal velocity in the liquid phase, the particles trajectories become linear until it hits the bottom of the separator. These sand trajectories give an insight into where to expect the sand particle to settle inside the Desander. Both methods are very useful and insightful for future analysis and design optimization when the properties of the fluid change with the change of the operating condition.

Dynamic Modelling and Simulation of A Three-Phase Gravity Separator

There are many studies addressing in detail, the separation mechanisms, sizing, and design of the crude oil separation process using the horizontal 3-Phase Gravity Separators. Surprisingly, however, there are very few publications about their dynamics, modeling, and simulation. An understanding of its dynamic behavior will facilitate the design and tuning of the device that can be used to regulate the water level, oil level, and gas pressure against feed variations. This Scientific Paper presents a full mathematical analysis, modeling, and simulation using Mathworks Matlab R2016b-x64, modeling and simulation using Aspen Hysys V10 of a Crude Oil Separation Process using a horizontal 3-Phase Gravity Separator. Equations developed called Bishoy’s Equations will help to operate this device and to find many parameters and to see the effect of a parameter on others. The Assumptions are: complete phase separation, the vapor phase behaves like an ideal gas, and liquids densities are constant. Also, in practice, separators are designed with internal baffles to promote laminar flow to increase the efficiency of the separator, but it has been assumed that there are no baffles here which is a big problem but with the aid of these equations, the horizontal three-phase gravity separator can be operated at its maximum efficiency. The following parameters were determined in the equations: The height of gas, height of the water, height of oil, the height of oil when jumping the weir, the pressure of the gas (in and out), the pressure of water (in and out), the pressure of oil (in and out), and the effect of increasing (control valve’s stem position) and decreasing (inlet volumetric flowrate) on these parameters has been studied. This paper can change the view on oil and gas extraction and processing and can help large oil and gas companies in Europe, Asia, and Africa.

Experimental validation of numerical two-phase flow in a horizontal separator

Multiphase flows have been a significant problem in the oil and gas industry, with many recent reports of failures in industrial piping and equipment due to erosion either from long-term liquid impingements or solid particles. One of the most efficient horizontal sand separators is the product developed by Specialized Desanders Inc., which is called the “Horizontal Desander.” It is a gravity-based separator, and the associated multiphase flow physics has been investigated in this research. This study analyzes the phase separation by applying multiphase numerical analysis using Star CCM + software. Experimental testing with the two-phase flow (air and water) was performed and compared to the numerical results. The Particle Image Velocimetry measurements applied to the two-phase experiment showed that the time-averaged, RMS of velocity fluctuations and the frequency analysis of the air-liquid interface are in an acceptable agreement with the simulation results. Knowledge of the different phase interactions and behavior of multiphase flow is essential in developing and optimizing gravity separators. The results from this study will be the steppingstone to simulate multiphase flows with more than two phases.

Effect of Temperature on Oil-Water Separations Using Membranes in Horizontal Separators.

The effect of temperature on oil–water separations is studied in this paper, focusing on the changed penetration velocities of water droplets on the separation membrane in a horizontal separator. A compact numerical scheme is developed based on the phase-field model, and the temperature effect is first theoretically analyzed regarding the key thermodynamic properties that may affect the separation performance. The computational scenario is designed based on practical horizontal separators in the oil field, and the droplet motions in the oil–water two-phase flow are simulated using our scheme under various operation conditions. It was found that a higher temperature may result in a faster penetration of the water droplets, and a larger density difference in the oil–water system is also preferred to accelerate the separation using membranes. Furthermore, increasing the operation temperature is proved to benefit the separation of water and heavy oil.

The Effects of Inlet Flow Rates and Slenderness Ratio on the Separation Performance of a Horizontal Three-Phase Separator

Summary In the first part of this work, the development of a capital cost optimization model for sizing three-phase separators was described. The developed model uses generalized reduced gradient nonlinear algorithms to determine the minimum cost associated with the construction of horizontal separators subject to four sets of constraints. In the second part, an experimental test rig was designed and used to investigate the effect of gas flow rate, liquid flow rate, and slenderness ratio (L/D) on the separation performance of horizontal three-phase separators. The results indicated an inverse relationship between an increase in gas and liquid flow rate and the separator outlet quality. It also indicated a direct relationship between an increase in slenderness ratio and separator outlet quality. The results also showed that the gradient change of the percentage of water in the oil outlet with respect to slenderness ratio decreased to ratios of 6:1. Hence, the separation rate increased. At ratios greater than 6:1, the separation still increases, but the gradient change in separation drops off, implying that the benefit in terms of separation is diminishing beyond this point. Therefore, the optimal slenderness ratio for technical reasons is 6:1.

A CFD study on hydrocarbon mean residence time in a horizontal oil\u2013water separator

This study presents computational fluid dynamics analyses on oil–water flow characteristics in a horizontal separator. The performance of these vessels are inferred from mean residence time and cumulative residence time distribution of the hydrocarbon phase inside the separator. The authors model a separator used by previous researchers and evaluate mean residence time of the hydrocarbon phase in a two-phase mixture of oil and water. Three different water-cuts of 21%, 32%, and 57% are used. Additional analyses are done to assess how certain geometric features of the separator influence hydrocarbon mean residence time. The results show that the addition of a second perforated baffle plate does not improve the hydrocarbon mean residence time significantly. However, introducing a downward slanting throat section between the primary zone and the gravity separation zone improves the hydrocarbon mean residence time at 21% and 32% water-cuts. The results suggest oil–water separators with a throat section may be more efficient than regular horizontal separators without the throat section at low water-cuts.

Modernization of Two-Phase Oil and Gas Separator

Separators play an important role in the basis of the technological scheme and field preparation of oil and gas. Separation is the process of oil separation from gas. Depending on the requirements for the feedstock, separators are distinguished according to the principle of operation and purpose. In this paper, the company "PT Pertamina EP Asset 3 Subang", Indonesia (Nirajani) is considered as an example. Dimensions, efficiency, reliability of equipment, capital and operating costs are the main indicators of separator work and productivity. "Subang PT Pertamina EP Asset 3 Subang" collection station has 3 horizontal two-phase separators (high pressure, low pressure and test separator). In 2020, it is planned to increase the extraction of raw materials. In this regard, the aim of this work is to modernize the existing two-phase horizontal separator operated at the field. To achieve this goal, it is necessary to study the design of the existing separator, and calculate its performance (Nirajani). After all the calculations, it is necessary to choose a separator suitable for performance. Modernization of the existing separator is economically feasible for this enterprise.

Evaluation of flow characteristics in an onshore horizontal separator using computational fluid dynamics

In the petrochemical industry, separation of oil from water is a very important process. Wells produce mixtures of gas, oil, and water which undergo a primary stage of separation inside horizontal gravity separators. The performance of these vessels is evaluated by measuring mean residence time (MRT) and residence time distribution (RTD). Although many researchers studied flow characteristics in horizontal separators, limited number of articles exist that discuss separator MRT and RTD with varying water-cuts. In this article, the authors study an experiment using a horizontal gravity separator by previous researchers and perform computational fluid dynamics (CFD) simulations on the same geometry under similar conditions. The simulation results show qualitative agreement with the experiments by previous researchers. As shown by experiments before, CFD results showed that MRT of the organic phase increased with increase in water-cut. In addition, the RTD characteristics show very similar trends between CFD and experimental results.

Computational Analysis of Effects of Location of the Diverter Plate and Inlet Velocity on the Efficiency of Two-Phase Flow Separator

Two-phase horizontal gravity separators are generally
 used in the petroleum industry for gas and liquid separation. There are several
 studies in the relevant literature that reports various methods to determine
 the optimum diameter and length of the separator. Although the diverter plate
 is used to increase the separation speed, there is not any exact approach for
 specifying the appropriate location of the diverter plate on the inlet pipe. In
 the present study, the main volume of the separator is defined for a particular
 amount of mixture of oil and gas. Effects of the location of the diverter plate
 and inlet velocity on the separation efficiency are investigated for three
 locations of the diverter plate (100 mm, 150 mm, 200 mm) and four different inlet
 velocities (0,25 m/s, 0,5 m/s, 0,75 m/s, 1 m/s) by means of computational fluid
 dynamics (CFD) method. Two-phase, three-dimensional (3D) and fully turbulent
 flow simulations reveal that the highest separation efficiency is obtained as
 99% when the straight diverter plate is 200 mm far away from the top inlet and
 the inlet velocity is 0,25 m/s.

Facile high-temperature synthesis of weakly entangled polyethylene using a highly activated Ziegler-Natta catalyst

A Polyhedral oligomeric silsesquioxane (POSS) modified Ziegler-Natta catalyst is reported to synthesize the weakly entangled ultra-high molecular weight polyethylene at a high temperature and with a high activity. Incorporation of POSS can form numbers of aggregates with a mean size of 48 nm adsorbing on the surface of SiO2. The structure of nanoaggregates is evidenced by the experiments and theoretical calculations where one POSS can coordinate with multiple MgCl2 molecules serving as an electric donor to the further immobilized TiCl4. The catalyst is thus featured by two distinct active regions positioned in the POSS/MgCl2 nanoaggregates and δ-MgCl2, respectively. The former regions present extremely low activity on ethylene polymerization, which function as horizontal separators for isolating the active TiCl4 sites and the growing chains. This catalyst exhibits an exceptional activity (i.e. 1.3 × 106 gPE molTi−1 h−1 bar−1) for the synthesis of weakly entangled polyethylene at 60 °C.

Investigating neutron back scattering technique for the detection of oil water separation levels in horizontal gravity oil separators

Neutron backscattering technique is investigated as an alternative way for measuring the level of water in the horizontal oil gravity separators. This study proposes adding boron of 350 mg/L to the water inside the separator to increase the relative oil to water count rate. A concept design for the injection system is performed with recycling of boron. A CFD model is constructed using ANSYS Fluent software to simulate the boron injection and withdrawal processes. Experiments are conducted parallel to MCNP calculations to investigate the effect on the backscatted neutrons when adding 350 mg/L boron to the water.

Linking the past and present through symbolic housing features: North Cyprus

Linking the past and present has been a major challenge in contemporary architecture as it raises the question of authenticity in design. While the influence of the past in residential architecture seems unavoidable, housing should also incorporate cultural features to uphold communication with their residents. Accordingly, this study suggests that the symbolic use of traditional features could be a useful approach to preserve the link between the users and contemporary housing. Based on deductive reasoning, this research has formulated the theory, and the results have verified the proposition. The case study focuses on the symbolic use of facade features of two recent periods of traditional architecture in Cyprus: the Ottoman (1571–1878) and British Colonial (1878–1960) in the contemporary mass housing facades. The results indicate that six facade features (arch, shutter, eave's brackets, cumba, window form and dimensions, overhanging elements, and horizontal separators) are the most preferred traditional features which, in view of a new interpretation, were used symbolically in the present mass housing facades.

Sizing Gas/Liquid Horizontal Separators Handling Nonstable Multiphase Streams

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 169444, ’A Method To Size Gas/Liquid Horizontal Separators Handling Nonstable Multiphase Streams,’ by J.L. Hernandez-Martinez, Pemex, and V. Martinez-Ortiz, Schlumberger, prepared for the 2014 SPE Latin American and Caribbean Petroleum Engineering Conference, Maracaibo, Venezuela, 21-23 May. The paper has not been peer reviewed. The sizing procedures for all of the process equipment in the oil and gas industry share a common assumption: The stream flow rate measured at the inlet is always constant or stable. This principle works fine for plants where the process conditions are controlled, but it does not apply to primary production facilities where the streams come from multiphase flowlines or wells. The sizing procedure described in the paper allows one to size horizontal gas/liquid separators considering nonstable flow rate at the inlet or fluctuations in the liquid fraction on the same stream. Background From a design standpoint, separators are split into three stages (or sections). Primary Stage. This is a mechanical operation; it uses an inlet diverter so that the momentum of the liquid in the gas causes the largest droplets to impinge on the diverter, forming droplets that are separated by gravity. The gas stream flows to the disengagement section. Secondary Stage. Liquid drops immersed in the gas stream are separated by gravity. This separation is governed by the settling liquid-drop velocity inside the gas phase. This velocity must be higher than gas-stream velocity to allow the drop to settle to the liquid phase. Tertiary Stage. This occurs on the mist eliminator. This is a device that allows small-sized droplets to coalesce to larger drops, which fall down by gravity to the liquid phase. These design stages or sections are shown in Fig. 1. The primary stage is designed on the basis of a simple volumetric balance, following some well-known rules. The most important parameter to consider in designing the secondary stage is the settling drop velocity inside the gas stream. This velocity can be calculated by performing a balance around each liquid droplet. This balance takes into account two factors, gravity and the drag forces applied by the gas stream. Liquid droplets settle at a constant velocity known as terminal velocity (for its calculation, as well as a discussion of the theoretical model used, please see the complete paper).