Effect of stopping operation for sulfur burning
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What methods do you use to remove sulfur deposits from Klaus catalytic reactors when they are shut down? We generally use fuel gas for this purpose, but it’s difficult to control the reactor temperature. Do you have any good suggestions?
Sulfur removal is usually achieved by burning fuel gas. Indeed, as the original poster said, it’s quite difficult to control the temperature at this stage; if not done properly, it can cause the bed layer to overheat or even reach extremely high temperatures. Therefore, it is essential to strictly control the oxygen content at this stage (increasing it gradually), while also preparing to inject nitrogen into the reactor. It is best not to inject steam to avoid damaging the catalyst.
Combustion is carried out using fuel gas and air, with strict control over the air supply to ensure that the fuel gas burns in a sub-stoichiometric condition (with insufficient oxygen) at 80%-90%, thereby preventing oxygen leakage.
We generally use high-temperature process gas to blow in sulfur, and then nitrogen
Reply to 3# 654262293: What should be done if carbon buildup occurs with this approach?
Reply to 4# Tianyu1: The sulfur inside the catalyst cannot be blown out; how should this be dealt with?
The method generally used is what the original poster mentioned, namely using fuel gas for desulfurization. But it also easily causes the catalyst to overheat or reach excessive temperatures. So in such cases, it is generally said that air distribution needs to be strictly controlled, but in reality this is just colloquial language. It has no practical use. The most practical approach is to add the cooled nitrogen at the beginning of sulfur injection with fuel gas, or when the injection time is not very long. Open fully the nitrogen purging line at the burner location, then roughly calculate the amount of air required for the fuel gas, and subtract a certain margin based on this figure. If you proceed in this way. If the temperature rise of the catalyst bed is still high, continue to reduce the air volume. When the effect is not significant enough, cooling can only be achieved by adding steam at the reactor. Nitrogen is added to the burner merely to increase the volume of the process gas. And it can dilute the oxygen content. The key to this process is to use as much nitrogen as possible, while keeping the amount of air as low as feasible under acceptable conditions. Active participation
Reply to 7# zhezi2009.wang: Will carbon buildup occur?
Once an over-temperature of the reactor bed is detected, cooling should first be achieved by injecting nitrogen into the reactor.
It seems this issue is quite troublesome; I’m paying attention to it. To summarize, sulfur is usually removed by burning fuel gas. Indeed, as the original poster said, it’s quite difficult to control the temperature at this stage; if not done properly, it can cause the bed layer to overheat or even reach extremely high temperatures. Therefore, it is essential to strictly control the oxygen content at this stage (increasing it gradually), while also preparing to inject nitrogen into the reactor. It is best not to inject steam to avoid damaging the catalyst. The method generally used is what the original poster mentioned, namely using fuel gas for desulfurization. But it also easily causes the catalyst to overheat or reach excessive temperatures. So in such cases, it is generally said that air distribution needs to be strictly controlled, but in reality this is just colloquial language. It has no practical use. The most practical approach is to add the cooled nitrogen at the beginning of sulfur injection with fuel gas, or when the injection time is not very long. Open fully the nitrogen purging line at the burner location, then roughly calculate the amount of air required for the fuel gas, and subtract a certain margin based on this figure. If you proceed in this way. If the temperature rise of the catalyst bed is still high, continue to reduce the air volume. When the effect is not significant enough, cooling can only be achieved by adding steam at the reactor. Nitrogen is added to the burner merely to increase the volume of the process gas. And it can dilute the oxygen content. The key to this process is to use as much nitrogen as possible, while keeping the amount of air as low as feasible under acceptable conditions. The method generally used is what the original poster mentioned, namely using fuel gas for desulfurization. But it also easily causes the catalyst to overheat or reach excessive temperatures. So in such cases, it is generally said that air distribution needs to be strictly controlled, but in reality this is just colloquial language. It has no practical use. The most practical approach is to add the cooled nitrogen at the beginning of sulfur injection with fuel gas, or when the injection time is not very long. Open fully the nitrogen purging line at the burner location, then roughly calculate the amount of air required for the fuel gas, and subtract a certain margin based on this figure. If you proceed in this way. If the temperature rise of the catalyst bed is still high, continue to reduce the air volume. When the effect is not significant enough, cooling can only be achieved by adding steam at the reactor. Nitrogen is added to the burner merely to increase the volume of the process gas. And it can dilute the oxygen content. The key to this process is to use as much nitrogen as possible, while keeping the amount of air as low as feasible under acceptable conditions.
Reply to 7# zhezi2009.wang: I think oxygen is insufficient first; stabilize the fuel gas first, then gradually increase the air flow. When burning sulfur, there should be a slight excess of oxygen – one must not rush things