What are the main factors causing pressure drop in hydrogenation reactors?

There are many factors that can cause an increase in reactor pressure drop; the main ones include a high content of mechanical impurities in the feedstock, catalyst coking, damage to the internal components of the reactor, and catalyst crushing.

Catalyst surface carbonization, crude oil properties,

The influencing factors include: ① An increase in reaction temperature leads to a higher cracking temperature, increased H2 consumption, and a decrease in pressure. ②Fluctuations in the amount of fresh hydrogen or failures in the fresh hydrogen generator can cause pressure fluctuations. ③As the moisture content of the raw material increases, the pressure rises. ④Leakage in the heat exchanger where the reaction products exchange heat with recycled hydrogen, as well as in the high and low pressure heat exchangers, caused a drop in pressure. ⑤Cold high-pressure loss of control.

Depending on the properties of the feed and fresh hydrogen, as well as the process conditions, the following types can be distinguished (with regard to reactors, pressure drops resulting from fouling of the feed fluid distributor and catalyst bed are mainly caused by the following factors): (1) Unclassifiable particles or mechanical impurities carried in the feed, such as debris from pipes and containers; (2) Metal deposits formed after the feed passes through the catalyst bed, such as sodium, iron, nickel, vanadium, etc.; (3) Inorganic salts, such as sodium chloride, ferric chloride, magnesium, calcium, etc.; (4) Organic substances: polymers of olefins, dienes, etc., which coking when exposed to high temperatures; (5) Coke powder and catalyst powder carried over from upstream processes; (6) Oxides and aromatic compounds that coking at high temperatures; (7) Others. . .

1) Excessive number of shutdowns 2) Too low purity of fresh hydrogen (this has been the case for a long time) 3) Poor quality of the feed oil 4) Hydrogen-to-oil ratio that remains low for an extended period 5) A large difference between the properties of the feedstock as specified in the design and those of the actual feedstock, preventing the catalyst from functioning properly under the actual conditions 6) Inadequate control of the temperature rise in the reactor beds, or problems with the settings; for example, 20 degrees for the first bed and 10 degrees for the second bed, resulting in uneven temperature distribution 7) Frequent adjustments to the reactor inlet temperature 8) Severe water content in the feedstock (we have encountered this issue); the feed oil tank is not dehydrated over time 9) The feed oil filter is operated in bypass mode for extended periods 10) Excessive use of bypass routes for recycled hydrogen 11) Other issues. That’s all I can think of

Be sure to pay attention to the increase in pressure drop caused by Fe and Ca, especially the increase in pressure drop caused by Fe. If the materials of the equipment and pipelines do not meet the required standards, over time corrosion of these components will result in Fe ions entering the reaction system, thereby causing an increase in pressure drop. Furthermore, damage to the internal components of the reactor, collapse of the catalyst bed, or crushing of the catalyst can also lead to an increase in pressure drop.

The problems mentioned on the third and fifth floors have all occurred here as well (char carried by overhead devices, Fe resulting from pipeline corrosion).

1. Unstable raw materials containing iron, metal impurities, inorganic salts, and mechanical impurities. 2. Chlorine present in the raw materials and hydrogen causes corrosion. 3. Collapse of the catalyst