Problems with hydrocracking sulfidation catalysts
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Our company intends to build a new hydrocracking unit, and it is currently in the feasibility study phase. Regarding the issue of catalyst presulfurization, I would like to ask everyone: since some research institutions already have catalysts that have been presulfurized, will plants in the future not need the high-pressure equipment, pipelines, and other facilities required for conventional sulfurization? I believe that catalysts that are pre-vulcanized directly can eliminate the need for a range of high-pressure equipment and shorten the commissioning time. Apart from the higher cost, are there any other drawbacks? Thank you all for your valuable suggestions!
Choosing a pre-vulcanized catalyst is highly beneficial for units starting up for the first time, as it reduces the commissioning time； However, sulfur injection facilities and processes should still be designed, as sulfur injection will still be required during the operation of the plant.
The sulfidation process is an important step for hydrogenation catalysts to achieve their performance specifications. The current trend is to pre-sulfidize the catalysts; in my opinion, it is not advisable to do this in new installations. Firstly, the additional investment required is not significant, being roughly on par with the cost of using a catalyst. Secondly, the amount of sulfur injected can be controlled by oneself; it can be adjusted to a lower level. During sulfiding, the pre-sulfided catalyst must be prayed to, asking that nothing go wrong with the compressor and that there be no fluctuations in the power grid; once venting occurs, sulfur cannot be replenished in the recycled hydrogen. When changing again, due to the maturity of the equipment, it is recommended to use a presulfided catalyst. Moreover, the sulfur injection facility can also supply additional sulfur during catalytic operation to improve catalyst activity. This post was last edited by 9001412 on 2009-2-10 07:46.]
The process design still allows for customization regarding whether to purchase pre-vulcanized catalysts.
The process should still be designed in such a way that, during normal production, it may be necessary to add a vulcanizing agent to the system in order to increase the catalyst’s activity
There are also those with a sulfiding agent injection port connected to the outlet of the crude oil tank; in this case, no high-pressure equipment is required
The additional investment is mainly for high-pressure pumps; in the case of wet vulcanization, it is low-pressure pumps. Therefore, in terms of vulcanization, the increase in investment is not significant. As for the time saved in startup, vulcanization only takes two days, so it’s not really significant. In my personal opinion, using pre-vulcanization is like striving for a higher quality of life. With money, it’s not just about having enough to eat and wear. There can be higher demands, and better enjoyment.
The activity is definitely not high, and the depth is insufficient. Moreover, the supply is limited, prices are high, so careful consideration is needed