How to deal with high oxygen content in gas?
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1. A malfunction in the chimney valve of the intermittent gasification furnace allowed blowing air to enter the gas holder. 2. The water seal at the inlet of the gas fan lost its water supply, resulting in the absorption of large amounts of air. As we know, when the oxygen content in the gas is high, there is a risk of explosion when operating valves, shutting down fans or compressors. In the first case, it is sufficient to shut down the faulty vaporizer; thereafter, the conversion system should increase the steam supply to prevent the catalyst from overheating, until the oxygen level in the gas tank drops. In the second case, it seems there is no other option except to shut down the fan, but this action carries a risk of explosion. Everyone is discussing what safe handling methods are available when the oxygen content in gas is high
If it exceeds 0.5%, the machine must be stopped immediately; otherwise, an accident will occur.
When oxygen levels are high, decisive action must be taken! The target I set is a reduction of more than 0.5%; if it exceeds 0.8%, production will be stopped! This post was last edited by 7276166 on 2009-2-15 16:45]
A high oxygen content in the ammonia synthesis plant can cause overheating in the shift reactor, leading to temperature loss of control. Once at our plant, the oxygen content was high, and the temperature gauge for the medium and high temperature stages reached its maximum value (800 degrees). There wasn’t enough time to shut down the equipment; after it stopped operating, before pressure could be released, the outlet pipe of the second stage of the medium and high temperature furnace cracked, resulting in a fire. It’s terrifying; half of the sky is red. Medium-Low-Low Process
5% reduction? ? Is it an ammonia synthesis plant? In an ammonia synthesis plant, if the oxygen content exceeds 0.5% and isn’t reduced promptly, it can be very dangerous
Not necessarily! Based on my experience, as long as the oxygen content is at 0.8%, and if the operations are carried out promptly and properly, at most there will only be fluctuations in the furnace temperature – of course, I’m referring to situations where the instantaneous oxygen content is high! If the oxygen level remains high continuously, then it’s a different story!
It is generally specified to be below 0.5%. If the oxygen content exceeds this limit, the load should be reduced immediately if it is above 1.0%; if it is above 1.5%, an emergency shutdown is required
The second scenario mentioned by the poster is very difficult to handle; if it occurs, the only option is to shut down the Roots blower by force. But this situation can be prevented: 1. Closely monitor the inlet pressure of the Roots blower during normal operation to prevent negative pressure from occurring. 2. Insert the water seal drain pipe into the water seal groove, which not only prevents air leakage from the water seal but also ensures that no air is drawn in under a certain negative pressure. 3. Install a negative pressure interlock device for the Roots blower, so that it shuts down automatically when negative pressure is detected.
If it exceeds 0.5%, the machine must be stopped immediately; accidents resulting from this have occurred time and again.
A high oxygen content in gas can cause the following problems: 1. Oxygen explosion in the gas; 2. Introduction into the purification system, which damages the conversion catalyst
Reduce by more than 0.5%: stop operation; reduce by more than 0.8%: shut down completely
If it exceeds 0.5%, stop immediately – safety first! ! ! Don’t joke around with your life! !
A high oxygen content is not necessarily an indication of a real problem; it could also be due to sampling issues or incomplete replacement, with air entering the system leading to an elevated oxygen level.
If O2 is above 0.5%, the machine should be stopped immediately; if it is a transient situation, reduce the output of the steam generator first, and then check issues such as the fan and water seal. If fluctuations in the converter temperature have already occurred, nitrogen is introduced at the converter inlet to prevent further temperature rise.
Yes, the action taken at that time was indeed to shut down the fans forcefully. The interlock settings for the fans in our factory are not adequate (only an interlock that shuts down the system down when the gas tank level is low has been installed). The suggestion regarding the 8th floor is good; thank you!
In our factory, due to the lack of responsibility on the part of the laboratory technicians, samples were not taken at the outlet of the gas tank for analysis in a timely manner; as a result, the excessive oxygen content was not detected in time, which led to an explosion in the desulfurization tower of the purification system. Peroxide is a concept related to safety; if peroxide is detected at a workstation, the relevant personnel should be given the authority to stop the machine immediately. Of course, it is essential to have accident prevention plans in place to avoid greater losses resulting from improper actions.
I fully agree with the comment above that \"peroxide is a concept related to safety; if peroxide is detected at a workstation, the person in charge should be given the authority to stop the machine immediately.\" When O2 exceeds a reduction level of 1%, even if there are issues with the sensory analysis, it is necessary to reduce the load at least until a new sample is available, and then shut down the system and allow it to vent. If O2 is greater than 0.4% but less than 1%, the operating conditions must be adjusted immediately; continuous sampling for analysis is required. If there is no improvement or if the situation worsens, the plant must be shut down.
Reduce load; shut down if it exceeds 5%.
It is better to use an online oxygen analyzer for control, as cascade control would be more appropriate
It should be an explosion in the electrostatic defouling tower; why would it be an explosion in the desulfurization tower? Is it a semi-dismantled desulfurization tower? Or a shift gas desulfurization tower?