Effective methods to reduce sulfur entrainment in process gas

1. Reduce the air velocity. 2. High-efficiency collectors, e.g., vertical types with internal packing. 3. High-temperature blending valves are not used.

1. The thickness of the collector mesh can be increased. This can be addressed during maintenance: a screen with a higher mesh count can be used, and then one with a lower mesh count (thicker wires) can be layered on top, which facilitates better capture by the screen over extended periods of use. 2. Reduce the temperature of the screen heating. While ensuring that the screen does not form sulfur deposits, it is possible to reduce the temperature slightly by lowering the heat supply; in other words, use steam with a lower pressure – avoid using 10-kilogram steam as its temperature is too high. 3. Reduce the flow rate of the process gas. If the flow rate of the process gas is too high, sulfur mist will be entrained; reducing the flow rate appropriately can also decrease the entrainment of sulfur mist. By adjusting the space velocity and contact time, as well as using screens or mist eliminators, sulfur loss caused by liquid sulfur mist entrainment in the final condenser can be kept at zero. But in reality, a slight amount of mist entrainment is inevitable. The range of sulfur entrainment by this mist is generally 2 to 4 kg of sulfur per 100 kmol of gas; for sulfur recovery units handling acidic gases, the resulting sulfur loss is approximately 0.2 to 0.4%. 4. Pay attention to preventing leakage points in the screen heating system in daily use. 5. Pay attention to checking whether the instrument readings are accurate on a regular basis.