Study on operation characteristics and fluid dynamics of internal loop air-lift reactor

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Abstract Air-lift reactors are widely used in the field of chemical and environment engineering, and it is of vital significance to accurately predict air-liquid two phase circulation and mass transfer behavior. In this study, a gas-liquid two phase flow model of internal loop air-lift reactor under steady state was proposed to calculate a series of fluid dynamic parameters, including circulation velocity v_L, gas holdup ε_G, and ratio of gas circulation β. Circulation velocity v _L and gas holdup ε_G was obtained via experiments in risers of 2 m and 6 m long and when the model parameter c₀ was 0.65, the relative average error between model calculation and experimental results for v_L and ε_G was less than 6.2%. The influence law of riser height on liquid circulation velocity and gas holdup was investigated. The results showed that with the increase of riser height, the circulating driving force increases, the circulating liquid velocity increased, and the average gas holdup decreased slightly. It was found that the ratio of gas holdup in the downcomer and riser related to operation parameters, such as reactor’s size an apparent gas velocity, and varied between 0.72 and 0.80.

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	LI Liang
	JIN Xiaoxia
	FU Chunming
	ZHANG Chengkai
	HAO Runqiu

Keywords： airlift reactor steady-state simulation gas phase circulation ratio circulation liquid velocity gas holdup

Received 2022-11-06;

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LI Liang, JIN Xiaoxia, FU Chunming, ZHANG Chengkai, HAO Runqiu.Study on operation characteristics and fluid dynamics of internal loop air-lift reactor[J] Chemcial Industry and Engineering, 2024,V41(3): 135-141

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