The desulfurization system of the hydrocracking unit has failed – how should this be handled?

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Our hydrocracking unit is designed to handle 800,000 tons per year. In the desulfurization system, the thrust bearings of the two liquid-poor pumps always reach excessively high temperatures – they are not allowed to exceed 75 degrees. Additionally, once one of these pumps is repaired, it doesn’t operate for long before it’s necessary to switch to the other pump in order to repair the faulty one. What should be done if both liquid-poor pumps fail? The desulfurization system’s liquid stream is stopped, resulting in an extremely high hydrogen sulfide concentration in the recycled hydrogen; depending on the sulfur content of the feedstock, this concentration can reach several tens of thousands of ppm, thereby inhibiting the reactions in the hydrogenation reactor! Personally, I think there are the following solutions; please experts point out any shortcomings. 1. Increase the amount of fresh hydrogen, release pressure through hydrogen circulation to enhance displacement. 2. Raise the reaction temperature accordingly, as an increased pressure enhances the depth of the reaction. 3. Reduce the processing volume. 4. Use feed oil with a lower sulfur content (during normal production, hydrogen sulfide levels in the recycled gas should be controlled at 300–500 ppm). Are there any other solutions? Please offer guidance if the current approaches are not appropriate!