The method of prolonging the operation period of the circulating oil system at the top of the fractionating column

Abstract

The invention relates to a method for prolonging the operation period of a circulation oil system on the top of a fractionation tower. Circulation oil which is pumped out from the top of the fractionation tower is subjected to heat exchange and is pressurized by a circulation oil pump; and a part of circulation oil is pumped out at the outlet position of the circulation oil pump and subjected to desalination treatment, and the process comprises the following three steps of: firstly, scrubbing the part of circulation oil by using a scrubbing solution so as to transfer a part of salt components in the circulation oil to the scrubbing solution; secondly, carrying out secondary scrubbing on the salt in the circulation oil and carrying out primary separation on the scrubbing solution from the circulation oil by using a rotational flow micro extraction separation technique; and mixing the circulation oil subjected to desalination treatment and other circulation oil, returning to the fractionation tower, and discharging the scrubbing solution or circulating and reusing the scrubbing solution for certain times and subsequently discharging out. By utilizing the method, the problems that the efficiency is lowered and the operation period is short because of salt deposition of the top circulation system are effectively overcome, the corrosion to the system is effectively reduced, and the long-period high-efficiency operation of the top circulation system is realized.

Description

technical field [0001] The invention relates to a method for prolonging the operation period of a circulating oil system at the top of a fractionation tower. It can effectively eliminate the problems of reduced efficiency and short operation period of the overhead circulation oil system of fractionation towers in petrochemical and coal chemical processes due to salt accumulation, and can effectively reduce system corrosion and realize long-term efficient operation of the top circulation system. Background technique [0002] In the process of crude oil processing, due to the constant changes in the properties of raw materials, salt formation and corrosion in the overhead circulating oil of the fractionating tower are prominent and common problems affecting the long-term efficient operation of the device, such as the circulating oil system of the fractionating tower overhead in the catalytic unit and coking unit . For example: in the delayed coking unit, the nitrogen compound...

AI Technical Summary

Problems solved by technology

However, looking at several countermeasures, we can see that for changing the operating conditions of the process, it is achieved by increasing the extraction temperature of the circulating oil, but this operating condition is restricted by many factors, and the operating flexibility is not great.

For the following measures, such as replacing the tray, changing the material of the pipeline, and locally strengthening the equipment, etc., the equipment is strengthened in the later stage to reduce the degree of corrosion. However, the corrosion of the equipment still exists, but the corrosion rate has slowed down, and the source of the corrosion has not been solved. question

On the other hand, replacing the trays and selecting pipelines with higher-grade materials will greatly increase the equipment investment cost. After a period of time, the equipment will still corrode and perforate, and then shut down to replace the equipment. This is only a temporary relief method , but not the fundamental means to solve the problem

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