Flash level
Thread Content
What effect does the change in entering flash steam pressure have on the flash liquid level?
When the pressure of the entering flash steam increases, the flash liquid level will also increase. When the flash steam pressure decreases, the liquid level will also decrease.
When the pressure is high, the liquid level will be high. This is mainly caused by the liquid level rising due to the high flow rate of the fluid, and also by the lack of flash evaporated gas for various reasons! On the contrary, if the pressure is low, the liquid level will be low.
There is an obvious relationship between the liquid level and pressure of the container. When the pressure is low, the liquid level of the container is higher.； When the pressure is high, the liquid level in the container appears lower. The two of them are inversely proportional to each other!
When the steam pressure entering the container is high, the amount of flash evaporation is small, so the liquid level is high.； When the pressure entering the container is low, the amount of flash evaporation is large, so the liquid level is low!
High pressure means high liquid level, low pressure means low liquid level! Because when the pressure is high, the solubility of the gas is greater according to Henry's Law, that is, the less gas is desorbed, and the liquid level will be high; when the pressure is low, the solubility of the gas is small, the desorption is large, and the liquid level will be low. Due to the large amount of flash evaporation, there may also be a high false liquid level!
I think it is more related to the opening of the outlet valve, and also because the volume of the gas phase (CO, H2, and part of CO2) is very small after being dissolved into the liquid phase, and it has little effect on its liquid level. What's more, what is flashing here is CO and hydrogen, which has little effect on the volume, but it will have some impact if the pressure is low. When the pressure is low (if the pressure is very low, it is likely to stop), the CO2 is analyzed, which will affect the volume of the liquid phase. I think the flash evaporation liquid level mentioned in the poster will not change much. Provide a set of data, the flow rate included is 193m3/h, the pressure is 55kg, the liquid phase out is 190.m3/h, the pressure is 12kg. The amount of flash steam is 1560 standard square meters. Let’s take a look. Only when the pressure is lower than the CO2 analysis pressure will it have a significant impact on the liquid level. Any corrections are welcome.
When the steam pressure entering the container is high, the amount of flash evaporation is small, so the liquid level is high.； When the pressure entering the container is low, the amount of flash evaporation is large, so the liquid level is low!
I agree with what was said on the 8th floor. When a small amount of gas (CO, H2, and part of CO2) is dissolved into the solution, the volume of the solution does not change much. The steam pressure affects the liquid level. Personally, I think that the larger the steam pressure, the better the pumping effect. The pressure above the liquid level in the flash tank is low, and the liquid level will naturally rise, and vice versa. Many friends mentioned "flash volume". Can you explain it? This is the first time I heard it.
Flash evaporation mainly uses pressure changes to suddenly reduce the pressure of high-pressure liquid to flash out the liquid in the solution. When the valve opening remains unchanged, the flash steam pressure is too high, which is not conducive to the flash evaporation of the gas. In this way, a large amount of solution will remain in the flash tank, causing the liquid level in the tank to rise, and vice versa. Therefore, we should pay attention to changes in pressure during daily work.