What is the difference in the total sulfur content in methanol at the inlet and outlet of the feeder in the thermal regeneration tower?
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In the low-temperature methanol washing process, the water content in the circulating methanol is within 0.5%; the operating temperature, pressure, circulation rate, and feed gas all are normal. However, the total sulfur and carbon dioxide levels in the purified gas exceed the specified limits. The total sulfur content in the circulating methanol is 13 PPm, while those levels in the purified gas are still above the limit. The total sulfur content in the methanol at the inlet of the heat regeneration tower feed heater is 1 PPm, and it remains within 15 PPm at the outlet. It is suspected that there may be a leak in the heat regeneration tower feed heater. I would like to ask everyone: is the total sulfur content in the methanol before and after the heat regeneration tower feed heater the same during normal operation? And what should be done if there is indeed a leak in the heat regeneration tower feed heater?
The total sulfur content in the methanol at the inlet of the feed heater in the thermal regeneration tower is 1 PPm, while it is 15 PPm at the outlet, which indicates a leak – sulfur-rich methanol has leaked into the sulfur-poor methanol. There’s no other way; we have to stop the vehicle to seal the leak.
Based on your description, the water content, temperature, pressure, and flow rate are all normal, but there are excessive levels of carbon dioxide and sulfur. The reasons can be identified by examining the regeneration status and washing efficiency. I have not encountered this situation personally, but we can provide information on our factory’s operations for reference. The water content is around 0.5%. The sulfur content in lean methanol is at most 80 mg/L. The carbon dioxide level in the purified gas obtained from bottom methanol should be between 2.5% and 3%, regarding sulfur content
By how much do total sulfur and carbon dioxide exceed the limit? Please confirm whether the wrong sample was used during the sampling process ； As I recall, that was a coil-type heat exchanger; for such coil-type heat exchangers, the probability of leakage in the low-pressure area is generally very low ； It is recommended to confirm this or look for other reasons related to the manufacturing process
Hello, may I ask if you have any data on the total sulfur content in methanol before the coiled tube heat exchanger and after the coiled ring heat exchanger?
Hello, the parameters required by our company are the same as those of your company. We tried increasing the circulation volume, but this only made the excess levels worse; reducing the circulation volume seems to be a better solution. Have you conducted any tests on the total sulfur content in methanol before and after using coiled tube heat exchangers?
The required level of total sulfur is less than 0.1 ppm; currently, the maximum level observed is 2 ppm. The required level for CO2 is less than 10 ppm, with the current maximum level being 40 ppm. Have you conducted any analyses of the total sulfur content in methanol before and after using a coil-type heat exchanger?
Brother, based on the data you provided, it can be determined that there is an internal leak in the coiled tube heat exchanger, which has affected its normal operation and caused the levels of H2S and CO2 in the hydrogen-rich gas to exceed acceptable limits. It’s better to shut down the equipment for maintenance; it’s advisable to contact the equipment manufacturer first, as it seems necessary to send the equipment back to the factory – there’s no way to fix it on site.
According to our process, in the heater, lean methanol is at high pressure, while rich-sulfur methanol is at low pressure. Theoretically, if the heat exchanger leaks, it should be methanol of low concentration that leaks into the methanol containing sulfur. However, according to your analysis, the level is 1 ppm for imports and 15 ppm for exports. I don’t know what the analysis method is? How many times has it been analyzed? Also, is there any way to analyze the CO2 content in the lean methanol at the heat exchanger outlet?