Temperature control issue in Klaus furnace
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Hello everyone, I’m new to the Claus process and am currently learning about Claus equipment as well as the related calculations. In the DC process, the air supply to the furnace is determined based on the concentration of H2S in the acidic gas, with the aim of maintaining a H2S/SO2 ratio of 2 in the process gas. Here’s a question: if the air volume is set according to the H2S concentration, and since the H2S concentration is high, the calorific value of the acidic gas is also high, then if the air volume is just enough to keep the H2S/SO2 ratio at 2, the flue gas temperature will be well above 1100°C. So how is the furnace temperature controlled in such a case? By using nitrogen? Steam?
Your acidic gas doesn’t contain ammonia, right? Otherwise, a higher temperature would be better! 2 is the theoretical value; the actual value may need to be kept lower for more reasonable control!
Hello, the acidic gas contains ammonia, and in large quantities at that. 49% hydrogen sulfide, 33% ammonia; if air with a H2S/SO2 ratio of 2 is introduced, I calculated using ASPEN that the temperature will reach 1600°C. So, how can the furnace temperature be controlled at around 1300°C?
You said 1100 earlier, and now you say 1300. . . . Steam is generally used in standard processes
The acid gas flow rate can also be adjusted, right?
Oh, I made a mistake – the ammonia level is relatively high; it’s better to set the furnace temperature at 1300. Thank you for your explanation.
The control temperature of the sulfur production furnace at 1300°C is to ensure ammonia decomposition. But your ammonia content is too high; once the ammonia concentration exceeds 15%, decomposition of ammonia does not occur very well, regardless of the temperature. You can consult Mr. Li Weiqiang from Duke for this.
This post was last edited by fpiliuwei on 2020-4-30 at 15:22. Based on the data you provided regarding the components of the acidic gas, it can be seen that the ammonia content is relatively high. There are generally three methods for treating aminoacid-containing gases: 1. Using conventional incineration furnaces with oxygen combustion + denitration devices ； 2.NH3 concentration
Thank you very much for your answer; I’ve learned a lot.
By maintaining a ratio of H2S/SO2 of 2, the degree of oxidation reaction is controlled; according to equilibrium calculations, that’s the corresponding temperature. For gases with a concentration of 80%, this ratio results in a temperature of around 1250°C. If the temperature is higher, it indicates that the acidic gas may contain hydrocarbons or amines. In cases where the gas contains amines, the mixing intensity at the burner is increased deliberately in order to reach a temperature of around 1400°C, thereby ensuring effective ammonia combustion.