Could an expert please explain the meaning of this passage? Thank you.

Both the increased purity of the recycled hydrogen and the increased volume of recycled hydrogen lead to an increase in the amount of hydrogen available; as a result, more heat is generated and the temperature rises

As the amount of circulating hydrogen increases, doesn’t the heat carried away also increase?

The purity of the circulating hydrogen increases, the hydrogen partial pressure rises, the reaction depth increases, and the temperature of the reaction bed rises. As the amount of recycled hydrogen increases, the hydrogen-to-oil ratio rises. Logically, with more recycled hydrogen, more reaction heat is carried away; and if the reaction depth increases, the temperature in the bed will also rise

An increase in the purity of recycled hydrogen and a rise in bed temperature mean that, with all other parameters remaining constant, the higher the purity of the recycled hydrogen, the higher the hydrogen partial pressure in the reaction system, which leads to greater reaction depth and consequently an increase in bed temperature. I disagree with the idea that an increase in the amount of circulating hydrogen leads to an rise in bed temperature! The following are my personal opinions: An increase in the circulation hydrogen flow rate does indeed raise the hydrogen-to-oil ratio within the reaction system, which facilitates a more thorough reaction. However, as a result of this increased hydrogen flow, the temperature at the outlet of the heater also decreases, and more heat is removed from the temperature inside the reactor. Moreover, if the crude oil has good properties and releases less heat during the reaction, this will lead to a decrease in the bed temperature. Therefore, the prerequisite conditions for this point should be clearly stated.

In my opinion, these two factors have a very limited impact on the bed temperature in actual production.

Hydrogen purity improved! In a sense, it is an increase in the hydrogen partial pressure! It is more conducive to the diffusion of hydrogen toward the catalyst! Further improve the refining of desulfurization, denitration, deoxygenation, demetallization, olefin saturation, and aromatic saturation! The amount of circulating hydrogen has increased! To some extent, it is to increase the hydrogen partial pressure! It facilitates the progress of the reaction! But there is a critical point! It’s that once the critical point is reached, the oil doesn’t have time to react and is carried out of the reactor by the circulating hydrogen! Hope this helps you

It refers to the fact that, with a constant rate of cold injection, increasing the hydrogen purity and the amount of circulating hydrogen essentially increases the reaction depth, which leads to an exothermic effect; as a result, the bed temperature rises

Whether the quantity is large or the purity is high, both are beneficial to the hydrogenation reaction; therefore, the bed temperature rises