What are the hazards of crude oil entering the reforming feed?

Crude oil leaks into the naphtha can be detected in a timely manner through parameters such as the temperature of the naphtha after cooling, the flow rate of naphtha leaving the unit, and the results of naphtha control analysis. Could there also be effects on subsequent processing steps?

Yes, samples are taken every 8 hours, and contamination is bound to occur in between. By the time it’s detected, the replacement process is already delayed. I just want to know how the density of naphtha affects the reforming process

This is a sampling analysis; if there is a leak, it won’t be detectable in the atmospheric and vacuum distillation units. Your company’s chain of management is really terrible. . .

If there is a leak in a heat exchanger, with a naphtha flow rate of 300 tons per hour, as long as the leak isn’t severe, even slight variations in the composition of the crude oil will result in a larger flow rate than this. I really haven’t heard of any refinery setting interlocks for the flow rate of the atmospheric tower overhead naphtha. How are such interlocks configured, and what are the reasons behind it?

If a heat exchanger only has a minor leak, it is indeed difficult to detect it right away. If a small leak in the heat exchanger allows crude oil to enter the straight-run naphtha, the following may occur: 1. The heavy components in the crude oil can cause a rapid increase in the pressure drop across the pre-hydrogenation catalyst bed, leading to catalyst deactivation. 2. Sulfur, nitrogen, and other elements present in crude oil can cause the pre-hydrogenation refined naphtha to fail to meet quality standards, lead to a decrease in the purity of the recycle hydrogen, and result in extremely high hydrogen sulfide levels. 3. Heavy metal components in crude oil can poison pre-hydrogenation catalysts and reforming catalysts. 4. Corrosion issues, and so on.

It depends on the duration of time; according to the testing and analysis cycle, some changes should be noticeable in the pre-hydrogenation unit, such as pressure drop and temperature rise； If substandard naphtha enters the reforming unit, some changes can be observed in the reaction temperature drop.

Due to the energy-saving requirements in recent years, heat exchange between the tower top gasoline and crude oil in atmospheric and vacuum distillation units leads to such situations. Usually, leaks of small magnitude go unnoticed, but by the time they are detected, it is already too late. After cooling, the atmospheric and vacuum gasoline is supplied directly to the pre-hydrogenation section of the reforming unit. At this point, the pre-hydrogenation feed pump is significantly affected; its specific gravity changes, and upon reaching the high-pressure heat exchanger, temperature variations occur due to differences in specific heat capacity. If a protector is present, its pressure drop will increase ； Later, when it reaches the reactor, this will lead to an increase in the temperature of the catalyst bed as well as an increase in pressure drop. In particular, the amount of quench hydrogen used to control the temperature rise will increase significantly; the exact figures are unknown, as such a situation has not occurred before ； After entering the distillation stage, to achieve the previous bottom temperature of the tower, the load on the heat carrier increases ； If the main operator still hasn’t realized this by then, the subsequent reprocessing step will be a mess once this batch of material gets in ；