Sealed washing method of slurry circulation pump in cyclohexanol unit

Abstract

The invention discloses a sealing water washing method for a slurry circulating pump in a cyclohexanol device. A sealing water washing system matched with the slurry pump comprises a high-position tank, a reaction system, a sealing water pump, the slurry circulating pump and a water pot. The high-position tank and the reaction system are connected through a communicating pipe, pressure balance is carried out to ensure that work pressure of the high-position tank is consistent with force of the reaction system, the sealing water pump is connected with the high-position tank through a pipeline and used for conveying water in the water pot into the high-position tank, an outlet of the high-position tank is connected with a pump cavity of the slurry circulating pump and a motor cavity through pipelines, and an inlet and an outlet of the slurry circulating pump are connected with an outlet and an inlet of the reaction system correspondingly. The height of the high-position tank is larger than that of the slurry circulating pump. According to the method, by means of the two pipelines, the influence of pressure fluctuations of the system on the slurry pump is avoided, the possibility that catalyst slurry enters the motor cavity is avoided, tedious operation is omitted, and operation stability and safety of a shield pump are ensured.

Description

technical field [0001] The invention relates to a device for preparing cyclohexene by partial hydrogenation reaction of benzene, in particular to a water washing method for a catalyst slurry circulating pump in a benzene hydrogenation system. Background technique [0002] Cyclohexanol is an important organic chemical raw material, widely used in synthetic fiber, synthetic rubber, industrial coatings, medicine, pesticides, organic solvents and other industries. At present, the main methods of producing cyclohexanol at home and abroad are cyclohexane oxidation and cyclohexene hydration. Because the cyclohexene hydration process is safer, energy-saving and environmentally friendly than the cyclohexane oxidation process, it develops rapidly and gradually replaces the cyclohexane oxidation process. [0003] The cyclohexene hydration process mainly includes partial hydrogenation of benzene to produce cyclohexene, extraction and rectification of cyclohexene, cyclohexene hydration ...

AI Technical Summary

Problems solved by technology

[0008] Once an abnormal situation occurs, the pressure will fluctuate greatly and at a high frequency. Due to the action lag of the differential pressure regulating valve, it is difficult to adjust the differential pressure in a timely manner.

When the pressure difference cannot be guaranteed, especially when the pressure difference drops suddenly, the slurry can easily enter the motor cavity, causing the shielding sleeve of the slurry pump to wear out and the bearing to wear out, resulting in the interlock shutdown of the entire reaction system

The more common ones are that when the pressure fluctuation of the reaction system is caused by the start-stop stage and other reasons, the pressure difference regulating valve needs to be continuously tracked, and the pressure difference between the sealed water pump and the reaction system is easy to deviate from the control range. The head flushing water volume and sealing water pressure fluctuate accordingly; the sealing water pump fails and stops, and the reaction system will be interlocked to stop. At the same time, due to the loss of pressure, the catalyst enters the shielding sleeve of the pump, and even back into the sealing water system, and the catalyst slurry is used before starting up again. Incomplete cleaning will result in damage to the pump

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