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In plethora of petroleum, chemical and heat transfer applications, T-junction is often used to partially separate gas from other fluids, to reduce work burden on other separating equipment. The abundance of liquid carryovers from the T-junction side arm is the cause of production downtime in terms of frequent tripping of downstream equipment train. Literature review revealed that regular and reduced T-junctions either have high peak liquid carryovers (PLCs) or the liquid appears early in the side arm [liquid carryover threshold (LCT)]. The purpose of this study is to harvest the useful features of regular and reduced T-junction and analyze diverging T-junction having upstream and downstream pipes.

Volume of fluid as a multiphase model, available in ANSYS Fluent, was used to simulate air–water slug flow in five diverging T-junctions for eight distinct velocity ratios. PLCs and LCT were chosen as key performance indices.

The results indicated that T (0.5–1) and (0.8–1) performed better as low liquid carryovers and high LCT were achieved having separation efficiencies of 96% and 94.5%, respectively. These two diverging T-junctions had significantly lower PLCs and high LCT when compared to other three T-junctions. Results showed that the sudden reduction in the side arm diameter results in high liquid carryovers and lower LCT. Low water and air superficial velocities tend to have low PLC and high LCT.

This study involved working fluids air and water but applies to other types of fluids as well.

The novel T-junction design introduced in this study has significantly higher LCT and lower PLC. This is an indication of higher phase separation performance as compared to other types of T-junctions. Because of lower liquid take-offs, there will be less frequent downstream equipment tripping resulting in lower maintenance costs. Empirical correlations presented in this study can predict fraction of gas and liquid in the side arm without having to repeat the experiment.

Maintenance costs and production downtime can be significantly reduced with the implication of diverging T-junction design.

The presented study revealed that the diameter ratio has a significant impact on PLC and LCT. It can be concluded that novel T-junction designs, T2 and T3, achieved high phase separation; therefore, it is favorable to use in the industry. Furthermore, a few limitations in terms of diameter ratio are also discussed in detail.

Offshore industries encounter severe production downtime due to high liquid carryovers in the T-junction. The diameter ratio and flow regime can significantly affect the excess liquid carryovers. Unfortunately, regular and reduce T-junctions have low separation efficiencies. Ansys as a commercial computational fluid dynamics (CFD) software was used to model and numerically inspect a novel diverging T-junction design. The purpose of diverging T-junction is to merge the specific characteristics of regular and reduced T-junctions, ultimately increasing separation efficiency. The purpose of this study is to numerically compute the separation efficiency for five distinct diverging T-junctions for eight different velocity ratios. The results were compared to regular and converging T-junctions.

Air-water slug flow was simulated with the help of the volume of the fluid model, coupled with the K-epsilon turbulence model to track liquid-gas interfaces.

The results of this study indicated that T-junctions with upstream and downstream diameter ratio combinations of 0.8–1 and 0.5–1 achieved separation efficiency of 96% and 94.5%, respectively. These two diverging T-junctions had significantly higher separation efficiencies when compared to regular and converging T-junctions. Results also revealed that over-reduction of upstream and downstream diameter ratios below 0.5 and 1, respectively, lead to declination in separation efficiency.

The present study is constrained for air and water as working fluids. Nevertheless, the results apply to other applications as well.

The proposed T-junction is intended to reduce excessive liquid carryovers and frequent plant shutdowns. Thus, lowering operational costs and enhancing separation efficiency.

Higher separation efficiency achieved by using diverging T-junction enabled reduced production downtimes and resulted in lower maintenance costs.

A novel T-junction design was proposed in this study with a separation efficiency of higher than 90%. High separation efficiency eliminates loss of time during shutdowns and lowers maintenance costs. Furthermore, limitations of this study were also addressed as the lower upstream and downstream diameter ratio does not always enhance separation efficiency.

Excessive liquid carryover in T-junction presents a serious operational issue in offshore production platform. Slug flow and diameter ratio of T-junction are considered as two major factors causing liquid carryover. Regular and reduced T-junction are being used as partial phase separator but their efficiency is low. Converging T-junction with two distinct diameters (primary and secondary) in branch arm is used to improve the phase separation efficiency. The motivation is to combine specific feature of regular and reduced T-junction to increase separation efficiency of existing T-junction without involving too much operational workover. The purpose of this paper is to numerically evaluate the separation efficiency of a converging T-junction design. The present model and its methodology was validated with in-house experimental data for 3 inches diameter flow loop.

The slug flow regime was simulated using incompressible Eulerian mixture model coupled with volume of fluid method to capture the dynamic gas-liquid interface.

The analyses concluded that T-junction with primary-secondary branch arm diameters combination of 1.0-0.5 and 0.67-0.40 managed to achieve 95 per cent separation efficiency. The research also confirmed that over reduction of T-junction secondary diameter ratio below 0.2 will lead to decrease in separation efficiency.

The present research is limit to air/water two-phase flow but the general results should be applicable for wider application.

The proposed design limited excessive workover and installation for current and existing T-junction. Hence, cutting down installation cost while improving the separation efficiency.

The present research resulted in higher separation efficiency, cutting down production down time and lead to operational cost saving.

The present research proposes an original and new T-junction design that can increase phase separation efficiency to over 90 per cent. The finding also confirmed that there is a limitation whereby smaller diameter ratio T-junction does not always resulted in better separation.

This paper aims to provide graduate students, researchers, flare design and operational oil companies with an overview on the flare incidents.

The design and operation of flares have been the subject of research and concern to the academicians and to flare design and operational oil companies. The flare incidents have been collected from several sources such as the technical, general articles, internet web sites, and internal reports. The flare incident types and causes have been reviewed. This paper presents an overview on the flare incidents. The paper presents a flare incident at an oilfield. The paper summarizes the causes and the results of the incident.

A lesson was learned that a flashback scenario could occur at the high‐pressure flares unless the flare system was designed properly. A flare system should be designed according to the standard codes. American Petroleum Institute API 521 recommended guidelines on the design of the relief system. John Zinc Company and GKN also recommended guidelines for the installation and protection of flares.

This paper presents the flare incident types and causes. The paper also presents an overview on a flare incident at an oilfield. The paper summarizes the causes and the results of the incident. This information can be beneficial in order to prevent similar flare incidents.

Various impacts of direct venting of natural gas into the environment, both in the upstream and downstream petroleum operations, often compel the chemical engineer to specify air pollution control equipment for installation on new and existing platforms/facilities. Flares, a special class of such equipment, are considered in this paper. The major types of flares used in the oil industry are reviewed and the principles guiding their operation and performance discussed. Information which would aid the choice of flare system for new applications is also discussed.

The purpose of the paper is to empirically explore the economic effect of advertising spending on the performance of banks on a sample consisting of all banks listed on the Dhaka Stock Exchange over the period spanning from 2011 to 2019.

A dynamic panel data autoregressive approach of two-step system generalized method of moments (2-SGMM) estimation technique has been adopted in this study to analyze the contemporary and carryover effect of advertising on the financial performance of banks.

The findings indicate that advertising expenditure boosts banks' accounting returns but not their market value. Furthermore, advertising has a negative carryover effect on the financial performance of banks and is statistically significant for operating profit and return on equity. This finding demonstrates that the economic benefits of advertising expenditure lapse entirely within the current period and ought to be treated as an expense since it does not bring any future return for the banks in Bangladesh. In addition, this paper also offers no critical contrast between the impact of advertising spending on the performance of both conventional and Islamic banks operating in Bangladesh.

To the best of the authors' knowledge, no study so far has looked into the effect of advertising on the profitability and the market value of the banks operating in Bangladesh, and this is the first study that explores this relationship.

The objective of the research work is to predict the volume of fluid drained from a cylindrical vessel without entrapping air through the drainpipe, and hence predict the location of the free surface of the liquid in the vessel.

A two‐dimensional axi‐symmetric numerical simulation has been made using a finite volume method that employs unstructured grids with cell‐wise local refinement and an interface capturing scheme to predict the shape of the free surface of water in a cylindrical vessel, thus simulating the entrapment of air in the drainpipe connected to the vessel.

A drain cover was placed on top of the drainpipe to delay the entry of air into the drainpipe. It was found that an increase in the diameter of the drain cover increases the amount of liquid to be drained out before the air could enter into the drainpipe. It was found that air enters the drainpipe at a particular height of the liquid in the vessel. However, when an initial rotational velocity was imparted to the liquid, the height of liquid when air enters the drainpipe depends on the initial bath height. As the initial bath height increases, air enters the drainpipe at a progressively higher bath height. But surprisingly when the drain cover is put in place the initial bath height, again, has no effect on the height of the liquid (in the vessel).

The outcome of the present research work has direct implications for steel making. If the drainpipe can be connected to the ladle the way it has been discussed in this paper then more steel can be drained before stopping the drainage in order to avoid air or slag entrapment.

The idea of putting a drain cover, using a larger diameter drainpipe and making the drainpipe connection to the vessel different so as to delay the appearance of air at the drainpipe is a new finding and the idea can be used by steel makers.

The purpose of this study is to focus on simulation of wire mesh demisters in multistage flash desalination (MSF) plants. The simulation is made by the use of computational fluid dynamics (CFD) software.

A steady state and two-dimensional (2D) model was developed to simulate the demister. The model employs an Eulerian-Eulerian approach to simulate the flow of water vapor and brine droplets in the demister. The computational domain included three zones, which are the vapor space above and below the demister and the demister. The demister zone was modeled as a tube bank arrange or as a porous media.

Sensitivity analysis of the model showed the main parameters that affect demister performance are the vapor velocity and the demister permeability. On the other hand, the analysis showed that the vapor temperature has no effect on the pressure drop across the demister.

The developed model was validated against previous literature data as well as real plant data. The analysis shows good agreement between model prediction and data.

This work is the first in the literature to simulate the MSF demister using CFD modeling. This work is part of a group effort to develop a comprehensive CFD simulation for the entire flashing stage of the MSF process, which would provide an extremely efficient and inexpensive design and simulation tool to the desalination community.

Introduction The majority of steam users realise the value of correct treatment and control when it comes to boiler water. Corrosion is recognised as a serious hazard and practically every plant uses some form of oxygen scavenging to protect the boiler from corrosion.

Boiler water treatment. Drew Ameroid U.K. Ltd has introduced Drewplex 530 boiler water treatment. This is a highly effective liquid formulation for steam generating systems, which is designed specifically to handle difficult iron conditioning situations.