What do you think are the main operational parameters that affect the quality of gasoline and diesel hydrogenation products? Why?

Hydrogen-to-oil ratio and reaction temperature – these are the most critical parameters; anyone studying hydrogenation knows about them and must understand them

I’ve never done this process before, so I’m not familiar with it. I’d like to gain some knowledge on it; I hope someone who is experienced can give me some insights

The main factors affecting the hydrogenation reaction include reaction pressure, reaction temperature, space velocity and hydrogen-to-oil ratio, feedstock properties, and catalyst. Once the device is determined, the properties of the raw materials, the catalyst, and the space velocity are essentially fixed and not suitable for adjustment. Hydrorefining involves two main types of reactions: the reaction of sulfur, nitrogen, and oxides with hydrogen to produce H2S, NH3, and H2O, which are then removed ； Hydrogenation saturation of aromatics and olefins. The reaction temperature has a significant impact on the hydrogenation reaction; generally, increasing the temperature speeds up the reaction rate, but it should not exceed 420 degrees, otherwise cracking reactions increase, the cetane number of diesel decreases, the desulfurization efficiency drops, and carbon deposition in the catalyst bed accelerates. A high oil-to-hydrogen ratio facilitates the progress of the hydrogenation reaction and enables effective removal of the reaction heat, thereby reducing the temperature rise in the bed; however, it results in higher energy consumption and operational costs. The reaction pressure affects the reaction rate primarily through the hydrogen partial pressure. Higher reaction pressures generally promote a greater degree of hydrogenation, thereby improving product quality; however, they also result in higher operating costs. During diesel hydrogenation, as the reaction pressure increases, the degree of purification reaches a maximum value before declining, and this is because continued increase in pressure after the feed oil has completely vaporized reduces the partial pressure of the feed oil vapor. It is recommended to make trade-offs and adjustments to the reaction temperature, pressure, and hydrogen-to-oil ratio.

What was said on the 4th floor is quite correct. To add more, for raw materials with better properties, it is possible to increase production by stabilizing other parameters and raising the space velocity. For raw materials with poorer properties, a comprehensive adjustment of pressure, temperature, space velocity, and the hydrogen-to-oil ratio can be employed; the specific approach should be determined based on actual conditions in order to achieve a balance between quality, production volume, and production costs. Each production unit has its own set of operational experiences.

The main process parameters for the hydrorefining of gasoline and diesel are: reaction temperature, reaction pressure, space velocity, and hydrogen-to-oil ratio. Reaction temperature: Increasing the reaction temperature can accelerate the reaction rate and reduce the content of impurities in the refined oil； However, increasing the temperature accelerates catalyst carbon deposition, affecting the catalyst’s activity. Reaction pressure: Increasing the reaction pressure can enhance the degree of hydrogenation, which is beneficial for the removal of impurities and for suppressing carbon deposition on the catalyst; however, the pressure is influenced by the load on the equipment. Air velocity: Reducing the air velocity means increasing the contact time between the feed oil and the catalyst, which enhances the degree of hydrogenation and facilitates the removal of impurities. However, a lower air velocity results in a reduced processing capacity of the unit, affecting its economic efficiency; moreover, it leads to increased carbon deposition on the catalyst. Hydrogen-to-oil ratio: Increasing the hydrogen-to-oil ratio, which in turn raises the hydrogen partial pressure, is beneficial for the hydrogenation reaction and helps to prevent the formation of carbon deposits. However, an excessively high hydrogen-to-oil ratio reduces the processing capacity and increases energy consumption.

Reaction temperature, hydrogen partial pressure, and catalyst.