Cracking tower for preparing high-purity nitrogen trifluoride

Abstract

The invention provides a cracking tower for preparing high-purity nitrogen trifluoride. Two vertically opposite gas hoods are arranged at the lower part of the outer side of the cracking tower; a filter pipe is locked and communicated between the two vertically opposite gas hoods; the filter pipe is internally and fixedly provided with an inner container for containing activated aluminum particles; a stirring mechanism used for stirring the activated aluminum particles is arranged in the inner container; and the stirring mechanism is driven by a driving mechanism to stir the activated aluminum particles. The activated aluminum particles are stirred by a sliding frame in the stirring mechanism, so that the activated aluminum particles are in full contact with the passing nitrogen trifluoride gas, impurities in the gas are fully adsorbed, and the purity of the nitrogen trifluoride gas is improved.

Description

technical field [0001] The invention belongs to the technical field of cracking towers, in particular to a cracking tower for preparing high-purity nitrogen trifluoride. Background technique [0002] In crude nitrogen trifluoride NF 3 Gas containing boiling point higher than NF 3 components such as N 2 O.CO 2 , HF and N 2 f 2 , boiling point lower than NF 3 The components have O 2 , N 2 and F 2 Wait. In the cryogenic rectification tower, the components with different boiling points are separated through the gas-liquid equilibrium process of multiple evaporation and condensation. [0003] Purification of NF by cryogenic distillation 3 In the process, before the gas enters the rectification tower, a large amount of high boiling point component impurities, such as N 2 O.CO 2 etc.; while removing low boiling point components such as O in the low temperature rectification tower 2 , N 2 . In the cryogenic rectification tower, liquid nitrogen is used as the cooling ...

AI Technical Summary

Problems solved by technology

[0004] Most of the active aluminum particles in the existing nitrogen trifluoride cracking tower are statically filled, and the static active aluminum particles obstruct each other and block each other so that they cannot fully contact with the nitrogen trifluoride gas. The impurities of the boiling point components undergo a large amount of thorough adsorption, which is not conducive to the purification of nitrogen trifluoride; in addition, the containment devices of active aluminum particles mostly use the shaft-driven rotary stirring method to stir the particles, because the transmission shaft will run through the containment devices for power Transmission, there will be a rotation gap between it and the outer wall of the container, which will damage the sealing performance of the container

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