Successfully resolved the issue of low processing capacity for acidic gases
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One: ‘The furnace we originally designed can burn not only hydrogen sulfide and ammonia, but also flue gases containing sulfur dioxide.’； Therefore, the acidic gas fed into the furnace in our design comes through two paths: one path goes to the furnace head to ensure the combustion of ammonia, while the other path leads to the furnace tail together with the sulfur dioxide-containing flue gas; the purpose of this is to allow sulfur dioxide and hydrogen sulfide to react directly at the furnace tail ； Third, ‘We have just started operations; the volume of acidic gas is very low, at only about 30% of full capacity, and the flue gas has not yet arrived.’ ； At first, we fed all the acidic gases into the furnace head; the temperature inside the furnace was only around 1220 degrees. As a precaution, some more gas was added, but that wasn’t a good idea ； 5. ‘Later, we came up with a solution: we directed some of the acidic gases to the front of the furnace and some to the back. In this way, the acidic gases at the front of the furnace underwent peroxide combustion, resulting in the formation of sulfur dioxide. The sulfur dioxide produced, along with the acidic gases, continued to react at high temperatures at the back of the furnace.’ The gas supply was completely turned off, while the total amount of acidic gas supplied remained unchanged; the temperature in the furnace rose to 1350 degrees. The temperature of the reaction bed did not change, and the furnace temperature could also be adjusted by changing the amount of acidic gas fed into the furnace. So far, the operation of our plant when handling low volumes of sulfur appears to be optimal
Reply 1# iceknife: Where does the sulfur dioxide-containing flue gas come from?
Reply to 2# Shandong Huaxing: The country’s seventh set of gasoline adsorption desulfurization units, capable of removing hydrogenated thiophenes and other organic sulfur compounds; the flue gas after regeneration contains sulfur dioxide
Reply to 3# iceknife: You could consider going straight into the hydrogenation reactor! That’s exactly what we do; there’s no problem!
The flue gas subjected to adsorption desulfurization contains a small amount of oxygen; if it enters the hydrogenation reactor for an extended period, it can have an impact on the operation of the hydrogenation section
Reply to 1# iceknife: The method you mentioned only addresses maintaining the temperature inside the combustion furnace. However, it doesn’t take into account the situation where the amount of acidic gas is low; even if the temperature in the combustion furnace is maintained, it’s still not possible to keep the outlet temperatures of the waste heat boiler and the condenser, as well as the temperature of the catalyst bed in the converter. I would like to know how you control the other aspects of the entire system. As you said, the amount of acidic gas is only 30% of that at full capacity; I think it will be difficult to control the temperatures of other parts of the system. Moreover, you are also burning gas as a fuel source. In my opinion, using gas combustion to maintain the system’s temperature is not a good approach. If the air supply isn’t properly adjusted, carbon black can easily form, and this carbon black will cover the surface of the catalysts.
Reply to 4# nxrjb: I’m not sure if it’s the exhaust gas from S-zorb; if so, it cannot be fed into the hydrogenation reactor due to its high oxygen content.
Low flow is working fine; I’m not sure what to do with high flow
Reply to 6# zhanghui5557: First, the temperature of the incinerator is primarily determined by the amount of gas it contains, the volume of air supplied, and the air-gas ratio. Unless there are serious problems with the CLAUS unit, causing the exhaust gases to be discharged directly into the incinerator, or unless the exhaust gas treatment system is inadequate and results in an excessive amount of H2S, which in turn causes the incinerator to overheat； II. The temperature of the CLAUS reactor is determined to a certain extent by the amount and ratio of H2S and SO2 fed into the reactor, as well as the temperature of the process gas at the inlet. Our current low processing capacity certainly has an impact on the reactor’s temperature; it is currently lower than the designed value. However, this isn’t a major issue – we can simply increase the steam supply to the reheater ； III. When the temperature of the hydrogenation reactor is normal, it does not change much. If the air distribution in the CLAUS unit is improper (our current overall air distribution ratio is not appropriate), this leads to excessive levels of SO2, and as a result the reactor temperature will definitely rise. It then becomes necessary to check the condition of the H2S/SO2 ratio analyzer, as this instrument is crucial for monitoring sulfur levels. IV. Our reactors do not currently have gas mixed in, as already stated in the post. Please offer your criticism and suggestions; our sulfur technology was quite backward in the past, and this is also the first time we are operating this system, so we are still in the process of figuring things out
Reply to 8# Guangzhou Sulfur: Every unit has its own design flexibility; if the usage exceeds the designed level by a significant amount (our flexibility is around 30%-110%), then it’s necessary to contact the dispatch team. We currently have only one set for sulfur processing, and we run into capacity issues when demand is high, haha
Reply to 7# Guangzhou Sulfur: It is the flue gas from S-Zorb; at present it cannot be fed into the reactor yet. I think feeding it into the reactor would yield better results. When the processing volume is normal, we will try to direct a portion of the flue gas into the reactor