The steam temperature for sulfuric acid production does not meet the requirements
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A 220,000-ton sulfur-based acid production system is unable to operate at full capacity due to steam temperature not meeting the required standards; seeking expert assistance for diagnosis! 1. The temperature of the sulfur burning furnace is normal, and the temperature in Section 1 is normal. 2. The boiler pressure difference is close to 4. 3. The inlet temperature at the second stage is raised by the bypass line, but the outlet temperature remains low. 4. The temperature rises by a dozen degrees during the transition from stage 3 to stage 4. 5. At a wind pressure of 20 Kpa, the temperature at the low-pressure steam outlet can reach 300 degrees; as the wind pressure increases, this temperature drops to 240 degrees. To maintain the steam temperature, the air pressure is currently controlled at around 30 Kpa. At the same time, activate the high-temperature bypass and cold shock to reduce the heat entering the boiler, control the steam volume, and maintain the steam temperature. The technicians initially determined that there could be the following 3 reasons. 1. The system’s thermal insulation has suffered severe aging, affecting the conversion metrics. 2. Catalyst deactivation, affecting conversion; insufficient conversion heat. 3. Scaling on the inner wall of the steam pipes affects heat transfer. I would appreciate it if an expert could give me some guidance on how to proceed!
Where have all the experts gone? Show up quickly!
Please upload the sulfur combustion conversion DCS screen. You can download a Haichuan app, which will make it easier to upload photos from your phone. I guess it’s due to the poor thermal stability of one layer of catalyst and the low outlet temperature of another layer.
Many data are needed to support the analysis; could you provide the DCS screen?
I’m not entirely sure about some of it; it seems to mean the following: 1. If the inlet temperatures at stages 1 and 2 are too high, it indicates that the bypass valve between stages 1 and 2 is set too wide or there is a problem with it, or else the high-temperature superheater isn’t working properly – in any case, heat isn’t being removed, which explains why the steam temperature is low. 2. At low loads, the steam temperature isn’t sufficient, while it’s only acceptable at high loads. Is that correct?
Also, the boiler pressure difference is 4 KPA, which is a bit high; it should be a 3+1 process. The temperature difference between stage 3 and stage 4 is only around 10 degrees, so I think it’s more or less the same. This needs to be compared with the normal conditions in the past
It’s that the steam temperature at low load is sufficient, but not enough at high load
It’s that the steam temperature at low load is sufficient, but not enough at high load
The inlet temperatures at the second and third stages of conversion are on the high side
Is the bypass valve on the flue gas side that is at a higher pressure closed?