The particle size of sulfur produced as a by-product of tannin desulfurization is very small – why is that?
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Our company uses coal gas to produce synthetic ammonia; for the desulfurization of semi-water gas, tannin is employed. The particles of the regenerated sulfur foam are very fine – a 350-mesh filter cloth cannot remove the sulfur, whereas fertilizer plants that use 150-mesh filter cloths achieve good results. What caused it? Please help everyone.
Basically, it is a regeneration issue; the regeneration process needs to be adjusted to increase the air volume； Additionally, for the solution components, the concentrations of tannin and V2O5 may be low; it is appropriate to increase them.
Caused by poor regeneration process: 1. High suspended sulfur in the desulfurization solution. 2. The regeneration temperature should be controlled between 38-42 degrees. 3. Reduce air volume and increase regeneration pressure (to ensure the injector is not clogged). 4. The composition of the desulfurization solution is imbalanced, and the ratio of alum to ferric sulfate is incorrect. 5. Continuous sulfur melting results in more by-products salts. :handshake :P
It depends on the specific desulfurization method. Take rosin-based desulfurization as an example – compared to catalytic desulfurization, it has the drawback that the sulfur particles are small and difficult to separate. The high regeneration temperature may cause sulfur to be produced at too fast a rate, resulting in smaller sulfur particles; therefore, it is essential to keep the temperature around 45 degrees. Additionally, the alkalinity of the solution affects the size of the sulfur particles; you can refer to books on sulfur crystallization for more information! !
The answers for floors 3, 4, and 5 are very thorough; I would add that it is necessary to determine the regeneration efficiency by regularly checking the concentration of the lean solution, and the quality of tannin is also important. It is necessary to check on the device whether all the nozzles above the regeneration tank are unobstructed.
We analyze the suspended sulfur content daily, and it is always below 1 g/L. Our current regeneration pressure is around 0.5 MPa; there are 36 nozzles in total, but usually 32 of them are used. It seems that the regeneration effect is also quite good.
By the way, don’t we conduct analysis on the contents of NaCO3 and NaHCO3? What’s the use of doing this analysis?
The contents of NaCO3 and NaHCO3 are analyzed to adjust the solution composition, thereby controlling alkalinity and pH value. By examining the levels of NaCO3 and NaHCO3, it is also possible to determine whether absorption is poor, regeneration is inadequate, or excessive amounts of by-products are being generated.
The desulfurization effect in our plant is very poor, and the use of filter presses also does not yield significant results