Treatment of sulfurized oil in hydrocracking units

The vulcanization process itself is a reaction cycle; after vulcanization is complete, the material is sent to the storage area. During this cycle, the rate of temperature increase and decrease is faster. However, it seems that dry vulcanization is now more common

Does the reaction’s own cycle not involve fractionation? Can the quality of sulfurized oil be guaranteed?

What indicators do you mean by quality? Sulfurized oil is originally introduced from the start-up sulfuration line; the sulfurizing agent is added according to the situation – so what’s the need for distillation?

Without fractional distillation and steam stripping for desulfurization, could the sulfur content in the sulfurized oil become too high, thereby affecting the process of the reaction raw materials?

During the reaction sulfuration phase, the reaction cycle and the distillation cycle can proceed simultaneously without interaction between them. If the amount of sulfurized oil decreases, it can be replenished from the raw oil tank or from the distillation process. There is no need to control the quality of the sulfurized oil during sulfuration; only the hydrogen sulfide concentration in the recycle hydrogen needs to be monitored. The distillation section can be heated in advance to prepare for the next steps

I suggest you first understand the principle of catalyst pretreatment by sulfurization; sulfurization involves high-concentration sulfur passing through the catalyst bed, so why do you want to remove sulfur first?

You are asking about what happens after the vulcanization is complete, right? After that, the reaction cycle and the distillation cycle are connected so that fresh material can be fed in, and the unqualified product is sent to the appropriate tank. Once the product quality is improved, that tank can be switched to for storing the qualified product. Of course, it’s also possible to first adjust the large-scale reaction and distillation cycles, as well as the quality of the circulating oil and the purity of the circulating hydrogen, before feeding in fresh material

The vulcanized oil from our last wet vulcanization process was eventually fractionated and recycled back into the reaction system; after vulcanization was complete, the unqualified material was sent to the designated storage area. If there is no recycling, a large amount of vulcanizing agent is required; recycling reduces the amount of vulcanizing agent needed significantly.

Regarding vulcanization, vulcanization. It involves using low-nitrogen diesel for vulcanization; during this process, DMDS is injected, and it reacts with hydrogen to produce hydrogen sulfide. When the concentration of hydrogen sulfide reaches a certain level… Converting an oxidized-state catalyst to a sulfided-state catalyst – during the sulfidation process desulfurization also occurs; your goal is to turn the catalyst into a sulfided state, so how is it possible to have desulfurization as well? The absorption tower can only be put into use when the unit switches to wax oil. There are also issues related to the process; well, at least that’s what I understand. Loop. A long cycle before returning to the feed buffer tank after passing through the unconverted oil. Circulation is stopped only when vulcanization is complete and wax oil is officially switched in. Transfer to the unqualified sludge oil tank i. I’m not sure if the answer is correct.

Question 1: How is the sulfurized oil in the hot-high-pressure process with oil involved circulated, and what is the flow path? Please provide detailed instructions. Question 2: Does the sulfur content in the circulating oil affect the amount of sulfur injected? How to control the sulfur injection amount? How to eliminate the impact of variations in sulfur injection amount on bed temperature?