The impact of high oxygen content on conversion
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Our company uses a medium-string low-conversion process; the oxygen content in semi-water gas is required to be below 0.5. In actual operation, the oxygen content rose to 2.0, so we took measures such as reducing the feed volume, increasing the steam supply, and raising the opening degree of the gas bypass line, which helped to keep the temperature under control. According to the regulations, this situation should have led to shutting down the plant. I wonder what other hazards might arise from high oxygen content aside from its impact on temperature?
Congratulations! You dare to drive with an oxygen level of 2.0%, and the gas generation and conversion processes haven’t exploded either – what courage, you’re amazing! But if this is done several times, the catalyst will run out soon.
Wow! Really? I thought it was mainly toxic to low-volatility coals. Is there any explosive limit for this substance?
Our plant once experienced an explosion in the coke filter when an operator performing backwashing on it did so due to high oxygen levels. It is required to stop the vehicle; remember that next time!
The original safety technical regulations for small nitrogen fertilizers issued by the Ministry of Chemical Industry required that production be halted when the O2 level in the gas reached 1.0%. Although there are studies indicating that it can be reduced to below 2.0%, no regulations have been established in this regard. Do you still dare to carry out production at 2.0%? Don’t those in charge of production fear ending up in prison and having to rely on the government for sustenance in case of an explosion?
The main reason for the high oxygen content in nitrogen fertilizers lies in the gas generation section; it is necessary to thoroughly investigate the causes and address the underlying issues. In particular, the gas valves downstream must not leak, and it is absolutely forbidden to take risks in violation of safety rules by disregarding the lives of the workers on duty. If an accident resulting from negligence occurs, it will be too late to regret it! Quick! Most small nitrogen fertilizer factories are now in private ownership; the owners won’t tell you to carry out production regardless of safety – if something goes wrong, it’s entirely your responsibility, as the owners won’t take any blame on your behalf.
Is there something wrong with the oxygen content analysis data? Otherwise, if it has reached 2.0 and it’s just the hotspot temperature that is high, then that’s really fortunate! Thank goodness!
Remember, never take life and responsibility lightly! ! :@
A high oxygen content can cause a sharp rise in the temperature of the medium shift catalyst bed! The burning of the catalyst leads to its deactivation, and in severe cases, it can reduce the performance and lifespan of the steel components used in the medium shift furnace! There is also a risk of explosion when there is an excess of oxygen. In the chemical industry, excessive oxygen is a serious problem, so it is essential to control the oxygen content in the process gas. If this level exceeds the allowable limit, immediate shutdown and isolation of the gas supply are necessary!
In accordance with the operating procedures for adjustments: when the O2 content in semi-water gas reaches 0.8%, the operation should be reduced; at 1.2%, shutdown is required. If it reaches 2.0% without shutting down, the responsibility for the incident must be investigated, and those involved as well as the production supervisors should be punished!
It has a significant impact on the catalyst, preventing certain of its components from being reduced; I’m afraid it won’t work for long.
I really see now – your leader is an amazing person; high oxygen content is what poses the biggest challenge in ammonia synthesis.
First of all, it is necessary to implement the requirements of laws, regulations, and standards related to work safety in order to ensure proper work safety practices. Secondly, such issues don’t need to be discussed. Thirdly, it is recommended that the poster reconsider the issue and consider installing an oxygen content interlock system; the plant should be shut down automatically if the oxygen content in the gas exceeds 0.5% to ensure safety.
You’re amazing. I’m the one who handles the transformations; you’re lucky no chain reactions occurred. You need to be careful when the oxygen level reaches 0.5, and at 0.8 it’s time to reduce the amount used. At 1.2, it’s definitely time to stop using gas – this isn’t something to take lightly; it involves lives and the survival of the factory
Is it true that in our factory, we take measures to reduce the oxygen level when it exceeds 0.5? Yet your factory continues to operate with an oxygen level of 2.0 – what’s the use of having a production manager and dispatcher then? It’s too dangerous
Brothers, your factory is several times more advanced than ours was back then; I guess your gas storage tanks are almost at capacity. If the oxygen level often exceeds the limit suddenly, it’s usually due to issues with the furnace, such as the gas supply valves not closing properly, a low furnace temperature, or a thin carbon layer. Back then, we would reduce the oxygen level once it reached 1.5%, and we continuously monitored the trends in oxygen levels; if it reached 1.8%, we would shut down the system immediately. We continued to operate in this manner for two years without avoiding the fate of bankruptcy. I remember that for a 0.1% increase in oxygen content, the temperature rise is 8-10 degrees in the high-variation case, and 5-8 degrees in the low-variation case (please forgive me; my memory might not be accurate).
In November 2005, at our factory, an operator in the gas production section closed the wrong valve, which caused the Roots blower to operate in reverse mode; as soon as the gas supply was connected in the conversion section, there was a loud noise……
It’s terrifying – people can still survive with an oxygen level of just 2%. It’s not easy. Could it be that the catalyst is still intact, functional, and retains its catalytic properties? !
Safety is not guaranteed! ! ! ! Process accidents are easy to handle, but human accidents are serious – lives are at stake! ! ! ! ! ! ! !
May I ask if the gas production unit used in the original post relies on coal gasification or natural gas/steam hydrocarbon conversion? If the latter is used, it’s possible that too much air is being supplied to the second-stage furnace! You can reduce the amount of air, but to ensure a low CH4 level, you can increase the temperature of a certain section of the furnace slightly; that will solve the problem! If it’s the former, then it’s just as Shang Hai said upstairs!