The chloride ion level at the bottom of the flue gas scrubber in the FCC unit remains high; could experts advise on other areas that should be checked? So far, water, flue gas, and alkaline solutions have been checked.
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The chloride ion level at the bottom of the flue gas scrubber in the FCC unit remains high. I would like to ask what other aspects should be checked; so far, we have examined the make-up water, flue gas, and alkaline solution.
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In addition to water, flue gas, and alkaline solutions, the following areas should also be carefully checked: 1. **Feed oil**: Verify whether the chlorine content in the FCC feedstock (especially residue) is high, as this is one of the main sources of chlorine. 2. **Catalyst**: Pay attention to whether the catalyst itself contains chlorine, or releases chlorine during regeneration. 3. **Internal system leakage**: Check for leaks from process condensate, coolers, etc., that may introduce chloride ions. 4. **Dechlorination/desalination unit**: Check whether the upstream pre-treatment processes such as electrodialysis are operating properly. 5. **Tower internals/packing**: Check for corrosion products or deposits that release chloride ions. 6. **Sampling and Analysis**: Verify the accuracy of the sampling points and analysis methods to rule out false elevations. It is recommended to prioritize checking the chlorine content in the crude oil and the dechlorination processes upstream, while also verifying the accuracy of the data. .
What is the level of chloride ions in the water at the bottom of your tower currently, and what is the value?
Around 500, with an index of 750
At present, samples have been taken from everything ranging from the raw materials to the acidic water and the desalinated water from the top circulation system, as well as from the flue gas. Chlorine imbalance: Date, Raw material chlorine, Flue gas chlorine, Acidic water, Desalinated water from top circulation, Chlorine at the bottom of the scrubber tower, Effluent water, Balance. On the 19th: 10 mg/m³ / 5 t/h, 511 mg/L; 23 t/h. On the 20th: 7.5 mg/kg, /, /, 5 t/h, 23 t/h. On the 21st: 8.3 mg/kg, 30 mg/m³, 15 mg/L, 5 t/h, 496 mg/L, 23 t/h. On the 22nd: /, 18 mg/m³, 20 mg/L, 9 t/h, 8.9 mg/L, 25 t/h. Currently, the level of chlorine in the raw materials has dropped to around 1, but the chloride concentration remains high. All kinds of water and alkaline solutions in the flue gas desulfurization tower have been used, with no abnormalities observed.