The γ CT Measurement And CFD Simulation Of Rushton Stirred Tank Bioreactor

Gas-liquid stirred tank bioreactor have been widely used in biochemical engineering, Rushton gas-liquid stirred tank bioreactor has been used as a typical gas-liquid stirred study object, in which the dimensions and distribution of gas holdup as the basic characteristics to describe the gas-liquid decentralized effect. Other hand, the gas-liquid stirred impeller rotating liquid with a strong shear, overfall and liquid circulation may cause harm to cells, how to minimize the shear stress while increasing demanding gas, as a important judgement factors of stirred tank bioreactor design study.Gamma-rays CT technology has many merits, such as non-contact, non-intrusive flow field, measurable opaque, high-temperature, high-pressure system in steel containers, and also can get two-dimensional gas holdup distribution at a one-time with accurate results. These advantages is important to the measurement of the Stirred Tank Bioreactor.In recent years, rapidly developed computational fluid dynamics (CFD) also provided an effective means to study the biological behavior of fluid. use computer numerical computing capability to solving some of the theoretical fluid mechanics equation. Get sub-microscopic point of view from within the fluid of the stirred tank simulation analysis to obtain different parts of the fluid within the biological blender behavior, as well as pressure, velocity, gas holdup, and other important parameters studied.Findings were as follows:â‘ Increased ventilation, required corresponding rotate speed to achieve complete dispersion critical speed also increased.â‘¡ventilation unchanged, when the stirring speed exceeds the critical speed, continue to increase the stirring speed has a small contribution on gas holdup, but would make the gas holdup distribution becomes more uniform at the top of impeller spatial;â‘¢When more than critical speed, maintaining the speed and increase the ventilation, it will increase gas holdup.As the gas-liquid biological stirred, there are strict requirements on gas radial distribution and shear stress, so this paper figure that the critical speed is the best option. Because of each specific biological cells have their own demand for dissolved oxygen, each time need to design the necessary ventilation of cells for their characteristics, dispersed in the gas phase determined by the state of ventilation and gas holdup size determine the corresponding critical speed. This is to ensure the gas dispersed plenitude and minimize the damage of shear stress to cells.