In water-coal slurry gasification, is there something called water explosion? ? ? ?
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This post was last edited by lflsedin on 2016-2-16 at 10:57. In coal water slurry gasification, is there something called water explosion? ? ? ? Looking forward to the expert’s recovery! ! !
Incident details: While vaporizers A and B were in operation, preparations were made to start vaporizer C and shut down vaporizer A. After Furnace C was started, Furnace A was shut down. After flushing the slurry pipeline, the operator prepared to open the drainage valve, but accidentally opened the valve of Furnace B instead, causing the slurry to flow out. This caused Furnace B to shut down; a fault in the oxygen valve prevented it from closing in time, allowing large amounts of oxygen to enter the coal slurry pipeline and escape through the nozzles. Friction during this emission led to a fire and explosion, destroying the entire pipeline.
Does it refer to the slurry being too dilute, or to boiling out caused by a failed interlock due to an excessively high liquid level in the quench chamber?
I understand that it was likely due to the coal slurry being too dilute, or water being introduced into the coal slurry when the pump started operating; the water valve wasn’t closed properly, which allowed a large amount of water to enter the gasification furnace. Since there was still flow indicated by the coal slurry flow meter, the gasification furnace couldn’t initiate an automatic shutdown, resulting in an explosion caused by an excess of oxygen in the furnace. Alternatively, an excessively high liquid level in the quench chamber of the gasifier, combined with poor drainage, can cause the liquid level to rise and flood the water-gas outlet pipeline, resulting in poor exhaust flow and pressure buildup in the gasifier that may lead to an explosion. (I have some humble opinions; I hope professionals can provide their feedback.)
It’s because the vaporization system chain isn’t working properly; the furnace should be shut down and then the oxygen and coal slurry pipelines should be purged. If that system chain doesn’t work, there’s nothing else that can be done. The main reason is that the valves were not properly verified
I remember having read an article before about explosions that occur in gasification furnaces when water gets inside them, but I can’t find it anymore. It seemed to talk about explosions happening when the temperature in the gasification furnace exceeds 1000 degrees and water gets in (without oxygen entering)~~ I can’t recall the details exactly, so I’m hoping experts can explain this to me. Does this situation really exist? ? If possible, please describe it more clearly! ! I thank you in advance! ! Hehe:handshake
Theoretically, an explosion in the vaporization furnace due to water ingress is unlikely, but in practice, water ingress can cause localized extinguishment of the fire inside the vaporization furnace. As a result, oxygen that has not had time to react and burn rises to the gas area, where it comes into contact with the hot gas and causes an explosion. The so-called water passing actually still refers to peroxide.
It was likely an explosion caused by the backflow of syngas under high temperature and pressure.
Hehe, heroes see things the same way – you’ve hit the nail on the head. In a word, it’s actually a peroxide explosion!
During the initial startup of Texaco’s gasification plants, someone accidentally opened the water valve used to flush the coal slurry circulation pipeline, which led to an oxygen explosion; it wasn’t an explosion caused by water, at least I haven’t heard of such a thing. What is mentioned on the second floor is a brief account of the explosion of a coal slurry pipeline at a factory in Nanjing last year; please be careful to make the distinction.
Could this situation be caused by rapid evaporation of liquid water once it enters, leading to a sharp increase in pressure? If the pressure is not relieved in time, this could result in an explosion – similar to the explosions that occur when water is added to a boiler that has been dry. It’s just a guess; let’s discuss it together.
Overwatering means adding too much water. In cases of excessive water addition during gasification, the following areas are involved: 1. Water from the slurry pipeline flushing system leaks in, resulting in an excess oxygen-to-coal ratio and subsequent oxygen explosion ； 2. A false liquid level appeared in the quench chamber of the gasification furnace; the control setting was too high, resulting in water entering the combustion chamber. The water inside the furnace caused turbulence, damaged the furnace bricks, and led to overpressure. But this situation is actually very difficult to occur, as the syngas will carry a significant amount of liquid.