Effect of Swirl Gas Injection on Bubble Characteristics in a Bubble Column

Swirling gas injection is a well-known technique to improve mass transfer in bubble columns. It can be used to create small bubbles with a high surface area-to-volume ratio, which is beneficial for mass transfer. Swirl gas injection can also be used to create a more uniform bubble size distribution and improve the mixing of gas and liquid in the column. This study aims to determine the impact of swirl gas injection on bubble properties, including bubble shape, size, and velocity. A bubble detection approach has been developed for quick and precise determination of bubble size distributions in gas-liquid systems. Advanced digital image processing, including edge detection and bubble edge recognition, is used in this method. The experiment is conducted in a bubble column at a height of 57 cm and 61 cm. The column had a ring sparger and was made of Plexiglas. Tap water was used as the liquid, while air from an air compressor was utilized as the gas phase. The shape, size, population, and velocity of the bubble are measured using a high-speed digital camera. According to this study, the average bubble size reduced as the impeller speed increased, while the population of bubbles increased when the sparger rotation speed increased from 30 to 150 rpm

Effects of Swirl Bubble Injection on Mass Transfer and Hydrodynamics for Bubbly Flow Reactors: A Concept Paper

Bubble flow reactors (BFR) are commonly used for various industrial processes in the field of oil and gas production, pharmaceutical industries, biochemical and environmental engineering etc. The operation and performance of these reactors rely heavily on a range of hydrodynamic parameters; prominent among them are geometric configurations including gas injection geometry, operating conditions, mass transfer etc. A huge body of literature is available to describe the optimum design and performance of bubbly flow reactors with conventional bubble injection. Attempts were made to modify gas injection for improved efficiency of BFR's. However, here instead of modifying the geometry of the gas injection, an attempt has been made to generate swirl bubbles for gaining larger mass transfer between gas and liquid. Here an exceptionally well thought strategies have been used in our numerical simulations towards the design of swirl injection mechanism, whose paramount aspect is to inhibit the rotary liquid motion but facilitates the swirl movement for bubbles in nearly stationary liquid. Our comprehension here is that the swirl motion can strongly affect the performance of bubbly reactor by identifying the changes in hydrodynamic parameters as compared to the conventional bubbly flows. In order to achieve this bubbly flow, an experimental setup has been designed as well as computational fluid dynamic (CFD) code was used with to highlight a provision of swirl bubble injection by rotating the sparger plate

Swirl Bubbles Effects on Hydrodynamic Characteristics of an Air-Water Bubble Column

Gas liquid bubbly flow reactors are used in chemical, petrochemical and bioprocess industries to enhance the mass transfer between the gas and liquid phases. The two-phase bubble column has gained huge attention for few decades due to its complex hydrodynamics and its impact on transport characteristics. The gas is dispersed to create a small bubble and disseminate them consistently to maximize the intensity of mass transfer. The motion of bubble’s rise in liquids is fascinating due to the bubble’s ability of adopting a variety of bubble’s motion patterns, which are characterized on the basis of bubble’s wakes, instability and size & velocity. This thesis describes bubble’s swirl effects on hydrodynamic characteristics in an air-water bubbly flow. The experimental set up comprises a cylindrical column, with a ring-cone sparger. The measurement technique contains a digital high-speed camera and image analysis software to track multiple moving bubbles. Bubble’s size, population and radial migration distance have been identified from consecutive pictures as a result of bubble’s edge recognition and projection on the basis of edge recognition for each of the bubble. The results from the experimental works show that by increasing the sparger rotation speed from 30 rpm up to 150 rpm, bubbles size is reduced, but bubble population is increased. Hence, the bubble migration distance is higher when the sparger’s rotating speed increases. Increasing gas flowrate results in larger bubble size, while promoting rotation induced by the sparger decreases the bubble size. As the rotating speed increase, the radial velocity of the water also increases. This is because, at high rotating speed, the velocity is dispersed more to the surrounding. Thus, at the center of the column, the liquid velocity is higher due to the bubble rising velocity is greater. As a conclusion, swirling bubble can enhance the mixing between air and water as well as provide larger migration of bubbles in the air water system. From this study, the efficiencyiv of the air-water mixing is increased, thus gives knowledge that by inducing swirl bubble in the flow, we can enhance the performance of the bubbly flow process

A CFD study of swirl effect on hydrodynamics in a gas-liquid bubbly flow reactor

Gas liquid bubbly flow reactors are used in chemical and bioprocess industries to enhance the mass transfer between the gas and liquid phases. In bubbly flow reactors, the mass transfer is most important parameter, which affects the product conversion and reactor performance. Mass transfer can be enhanced by achieving more efficient mixing. One such method is the application of rotation or swirl to the gas liquid mixture. Commercial code, Ansys Fluent 14.0 has been used to simulate the phenomenon prevailing in the bubbly reactors with conventional gas injection as well as rotating bottom plate through which the gas is introduced into the column. An attempt has been made to assess the effect of gas injection and swirl bubbly flow, gas void fraction and shear stress by the use of CFD Code. The results of the investigation showed that the gas void fraction increased with increasing in air gas rate for both conventional and swirl gas injectio

Effects of Swirl Bubble Injection on Mass Transfer and Hydrodynamics for Bubbly Flow Reactors: A Concept Paper

Bubble flow reactors (BFR) are commonly used for various industrial processes in the field of oil and gas production, pharmaceutical industries, biochemical and environmental engineering etc. The operation and performance of these reactors rely heavily on a range of hydrodynamic parameters; prominent among them are geometric configurations including gas injection geometry, operating conditions, mass transfer etc. A huge body of literature is available to describe the optimum design and performance of bubbly flow reactors with conventional bubble injection. Attempts were made to modify gas injection for improved efficiency of BFR’s. However, here instead of modifying the geometry of the gas injection, an attempt has been made to generate swirl bubbles for gaining larger mass transfer between gas and liquid. Here an exceptionally well thought strategies have been used in our numerical simulations towards the design of swirl injection mechanism, whose paramount aspect is to inhibit the rotary liquid motion but facilitates the swirl movement for bubbles in nearly stationary liquid. Our comprehension here is that the swirl motion can strongly affect the performance of bubbly reactor by identifying the changes in hydrodynamic parameters as compared to the conventional bubbly flows. In order to achieve this bubbly flow, an experimental setup has been designed as well as computational fluid dynamic (CFD) code was used with to highlight a provision of swirl bubble injection by rotating the sparger plate

Effects of Swirl Bubble Injection on Mass Transfer and Hydrodynamics for Bubbly Flow Reactors: A Concept Paper

Bubble flow reactors (BFR) are commonly used for various industrial processes in the field of oil and gas production, pharmaceutical industries, biochemical and environmental engineering etc. The operation and performance of these reactors rely heavily on a range of hydrodynamic parameters; prominent among them are geometric configurations including gas injection geometry, operating conditions, mass transfer etc. A huge body of literature is available to describe the optimum design and performance of bubbly flow reactors with conventional bubble injection. Attempts were made to modify gas injection for improved efficiency of BFR’s. However, here instead of modifying the geometry of the gas injection, an attempt has been made to generate swirl bubbles for gaining larger mass transfer between gas and liquid. Here an exceptionally well thought strategies have been used in our numerical simulations towards the design of swirl injection mechanism, whose paramount aspect is to inhibit the rotary liquid motion but facilitates the swirl movement for bubbles in nearly stationary liquid. Our comprehension here is that the swirl motion can strongly affect the performance of bubbly reactor by identifying the changes in hydrodynamic parameters as compared to the conventional bubbly flows. In order to achieve this bubbly flow, an experimental setup has been designed as well as computational fluid dynamic (CFD) code was used with to highlight a provision of swirl bubble injection by rotating the sparger plate