First alkane rectification tower reboiler on-line descaling device

Abstract

The invention discloses a first alkane rectification tower reboiler on-line descaling device. The device includes a first alkane rectification tower, a reboiler is connected underneath the first alkane rectification tower, a pipeline below a liquid inlet of the reboiler is equipped with a flush nozzle, and the nozzle supplies water through a process water pipeline and a flushing pump; and filter equipment is arranged on a drain pipe of the first alkane rectification tower. By adding cleaning and filtering units, the device provided by the invention can realize the purpose of on-line removal ofreboiler scale, greatly prolongs the operation cycle of production equipment for preparation of cyclohexanone by oxidation, thus providing guarantee for the continuous and stable operation of the equipment, ensuring the first alkane rectification tower a very economical operating state for a long time, and achieving ideal effects in saving energy and reducing consumption and maintaining the long-term stable operation of the production equipment. Also the control flow design has high degree of automation, is simple in operation, and is safe and reliable.

Description

technical field [0001] The invention relates to the field of preparing cyclohexanone by oxidation of cyclohexane, in particular to an online descaling device for an alkane tower reboiler. Background technique [0002] As an important raw material for chemical products, cyclohexanone is an important intermediate for the synthesis of adipic acid, nylon and caprolactam. At present, the methods for producing cyclohexanone in the world mainly include phenol method, cyclohexane oxidation method and cyclohexene method Three kinds, among which more than 90% of the cyclohexanone manufacturers in the industry adopt the cyclohexane oxidation process. The main feature of this method is that it requires a large circulating volume of cyclohexane and a low conversion rate to ensure the yield of cyclohexane. The gas-liquid ratio (air:cyclohexane) of the device is generally controlled at 35-40:1. The hexane conversion rate is controlled at about 3.5%, that is, more than 95% of the cyclohe...

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Problems solved by technology

In order to ensure the power of the four rectification towers, the alkane tower needs to control relatively high rectification temperature and pressure (0.5MPa, 155°C). This operating condition leads to some organic materials produced during the oxidation and decomposition of cyclohexane (cyclohexanone, cyclohexanol, epoxycyclohexane, adipic acid, etc.), these condensations form polymer organic substances and alkali substances entrained in the decomposition system, and will gradually gather in alkane The reboiler tubes of the tower will reduce the heat exchange efficiency of the reboiler, increase the heat loss, the power of the alkane recovery system will be insufficient, the circulation volume of the cyclohexane oxidation system will be reduced, and the consumption will increase. When the pollutant reaches a certain level and affects the balance of the system, the entire cyclohexanone production unit will be forced to stop for cleaning

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