What is the effect of quench water temperature on the composition of syngas?

Is it a problem of heat loss? ! ! ! ! Causes the temperature in the furnace to change, and thus the position of the three belts to change! ! ! Please give expert guidance! ! ! ! !

This post was last edited by shanxg on 2009-9-1 22:29. I remember I posted a question on the forum, but there was no result. At that time, some senior coal-water slurry gasification technicians believed that the gasification reaction would still occur in the downcomer because they also observed the phenomenon mentioned by the poster. To explain this phenomenon, the only explanation is that there is also a gasification reaction in the downcomer, rather than causing a change in furnace temperature as mentioned above. If there is a gasification reaction in the downcomer, it should be the exothermic reaction that dominates, which means that the conversion reaction is more likely to occur and the combustion reaction is basically impossible. But the poster said that both co and H2 increased and CO2 decreased, which seems to indicate that it is not a transformation reaction. According to this analysis, it can only be a water gas reaction, which is an endothermic reaction, but the environment in the downcomer is just suitable for this reaction. The unreacted high-temperature fixed carbon reacts with the quenching water to generate CO and H2, and the amount of CO2 decreases relatively. However, if it is a water-gas reaction, then when the temperature decreases, the reaction equilibrium should shift to the left. This is also the opposite of what the poster said. It is really strange! Let's discuss it and give you some ideas.

Why is no one interested in this topic? I thought about it again in the past two days and felt that this phenomenon was probably not caused by a gasification reaction in the downcomer. It is because when more quenched water enters the downcomer, it lowers the temperature of the process gas and also hinders the passage of the process gas, which reduces the diameter of the slag port in a disguised manner, causing the CO and H2 content in the process gas to increase and CO2 to decrease. This is similar to the phenomenon when the slag port shrinks. However, at this time, the pressure difference in the gasifier should increase. It may not be obvious and does not attract everyone's attention. I don't know if this analysis makes sense.

First of all, I would like to thank you for your participation. Also, I would like to explain that: The amount of water has not increased much. Due to scaling in the pipeline, after turning on the emergency chilled water, the chilled water flow meter showed an increase of only two or three cubic meters. I think it is because the pressure of the accidental quench water is higher than the pressure at the outlet of the quench water pump, so the water from the quench water pump is withheld. So only the water temperature dropped, and other parameters did not change much. 4#hjy2000

The water volume has not increased much, but the pressure has increased. When the chilled water is sprayed out, it will also cause the phenomenon of the slag mouth shrinking in disguise as I mentioned above. Haha, but this explanation always feels a bit far-fetched, so let’s ask the experts to take a look.

Are the quality of the accident chilled water and the chilled water from the chilled water pump the same?

Under normal operating conditions, when all oxygen and steam remain unchanged, the quench water has little effect on the composition of the syngas. Because the furnace temperature remains unchanged, the ratio of CO and CO2 is a constant, so what reaction occurs below is related to the following. Since the temperature remains unchanged, the equilibrium constant does not change, so only H2 and a small amount of other gases change, but these changes can basically be ignored.

It would be a good thing if the effective gas content increases. If there are no other bad effects, as the poster said, just lower the temperature of the quenching water.

Complex problems simplified: When the system is running, CO, H2, and CO2 have problems dissolving in water. Everyone knows that CO and H2 are difficult to dissolve, and CO2 is more soluble than CO and H2. Therefore, when the temperature of the gasifier water system decreases, more CO2 is dissolved in the water (low temperature, high solubility), so the CO and H2 contents increase, that's all.

The gasification quench water temperature is a design given by Texaco. We should implement the process indicators.