Khasani

Bio: Khasani is an academic researcher from Gadjah Mada University. The author has contributed to research in topics: Separator (oil production) & Two-phase flow. The author has an hindex of 2, co-authored 3 publications receiving 39 citations.

Development of liquid-liquid cylindrical cyclone (LLCC) separator for oil-water separation

Abstract: This study aims to determine the phenomena of water and oil separation and the performance of the Liquid-Liquid Cylindrical Cyclone (LLCC). The experiments were conducted with water and oil in a transparent LLCC separator that allows the visualization of the mixture. Series of experiments for various of inlet mixture velocity (Vm), inlet oil volume fraction (α), and split-ratio have been performed. Volume fraction of oil in the inlet were 0.06 (6 %), 0.1 (10%), and 0.15 (15 %). The examined inlet mixture velocity variations were 1.0 m / s, 1.5 m / s, and 2.0 m / s. Split-ratio was made in the range 25-70 %. The watercut in underflow were the variables measured. The experimental results show that the LLCC was able to separate water and oil and produced free water with concentration up to 98%. By increasing the value of the split-ratio, watercut in underflow increase and reached the optimum point. Optimal split-ratio observed is between 60 % and 70 % depend on the inlet oil volume fraction.

Visualization study on oil-water separation phenomena in a liquid-liquid cylindrical cyclone (LLCC) separator

Abstract: This study aims to understand the mechanism of oil-water separation process inside Liquid-Liquid Cylindrical Cyclone (LLCC) and the effect of operating parameters to the separation characteristics. Some experimental runs have been designed and commissioned, then the results from both experiments and visualization data are presented. General characteristics of separation process and flow behavior in the LLCC were explained in the form of qualitative observation and quantitative explanation. For the experimental runs, the LLCC was tested under the wide range of operating parameters such as inlet mixture velocity, split-ratio, and different inlet oil volumetric concentration. The acquired data includ e overflow oil volume fraction.

Multi-Fluid VoF model assessment to simulate the horizontal air–water intermittent flow

Abstract: Numerical simulation of the plug and the slug flow regimes have been performed using the Multi-Fluid VoF and Shear Stress Transport (SST) k–ω models in a horizontal pipe with 44 mm diameter. The superficial velocities during the current study were set at 0.16, 1.64 & 3 m/s for the gas phase and 1 m/s for the liquid one. The pressure and the velocity equations were solved together, utilizing the PIMPLE algorithm in all cases of the present study. The VoF model, as well as the experimental outcomes, were applied to assess the results of Multi-Fluid VoF model. The qualitative comparison of numerical results with the experimental visualization revealed that the Multi-Fluid VoF model simulates precisely the interfacial structure of slug and plug flows, as well as the chronological formation of the slug. The length ratio of the gas slug to the liquid slug goes up with the gas superficial velocity increment; this issue increases the probability at low liquid hold-ups and decreases the higher ones. The Multi-Fluid VoF provided much more matching with the mentioned probability changes in comparison to the VoF model. The pressure drop calculated using Multi-Fluid VoF in the Lockhart–Martinelli framework illustrated a 21.8% improvement averagely in comparison to the VoF model. The obtained transitional slug velocities showed that the Multi-Fluid VoF model presented a maximum error of 8.17% versus the experimental values, while the mentioned error for the VoF model was estimated at 22.01%. Notwithstanding the mentioned advantages, the Multi-Fluid VoF model significantly increased, both the execution time of simulation as well as the associated costs.

Numerical simulation of two-phase flow regime in horizontal pipeline and its validation

Abstract: Purpose: The purpose of this paper is to investigate oil-gas slug formation in horizontal straight pipe and its associated pressure gradient, slug liquid holdup and slug frequency. Design/methodology/approach: The abrupt change in gas/liquid velocities, which causes transition of flow patterns, was analyzed using incompressible volume of fluid method to capture the dynamic gas-liquid interface. The validity of present model and its methodology was validated using Baker�s flow regime chart for 3.15 inches diameter horizontal pipe and with existing experimental data to ensure its correctness. Findings: The present paper proposes simplified correlations for liquid holdup and slug frequency by comparison with numerous existing models. The paper also identified correlations that can be used in operational oil and gas industry and several outlier models that may not be applicable. Research limitations/implications: The correlation may be limited to the range of material properties used in this paper. Practical implications: Numerically derived liquid holdup and holdup frequency agreed reasonably with the experimentally derived correlations. Social implications: The models could be used to design pipeline and piping systems for oil and gas production. Originality/value: The paper simulated all the seven flow regimes with superior results compared to existing methodology. New correlations derived numerically are compared to published experimental correlations to understand the difference between models. © 2018, Emerald Publishing Limited.