Why is the temperature of the methanol coming out of the sulfur-free methanol flash tank lower than that of the methanol coming out of the sulfur-containing methanol flash tank?
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Why is the temperature of the methanol coming out of the sulfur-free methanol flash tank lower than that of the methanol coming out of the sulfur-containing methanol flash tank? Is it because the amounts of gas, namely CO and hydrogen, analyzed by the two are different? Moreover, the temperature of the methanol entering the sulfur-free methanol flash tank is five to six degrees higher than that of the methanol entering the sulfur-containing methanol flash tank @@654262293
What kind of craftsmanship? In the previous screenshot, it’s clear to see
One absorbs H2S and carbon dioxide, while the other absorbs only carbon dioxide. The saturation of methanol absorption varies, as does the heat of dissolution and the resolution capacity. But the temperatures are more or less the same
This post was last edited by Ye Xiang on 2016-9-21 at 20:17. In other words, is the amount of heat absorbed during the flashing process in the sulfur-containing methanol flash tank greater than that absorbed during the flashing process in the sulfur-free methanol flash tank? Or is it also related to the pipe diameter? Could you elaborate?
Flash evaporation is a change in pressure; as the pressure changes, the solubility of gas in methanol alters, causing the gas to escape from methanol. No heat needs to be added during the flash evaporation process. The pipe diameter does matter, but the pipe diameter from one tower to the two tanks doesn’t change, right? The change in pipe diameter to the flash tank corresponds to the phenomenon of sudden expansion of a pipe as described in chemical engineering principles, resulting in a decrease in pressure. The dissolved gas components of methanol in the two flash tanks are different. Dissolved gases release heat, while desorbed gases absorb heat
Flash evaporation is a change in pressure; as the pressure changes, the solubility of gas in methanol alters, causing the gas to escape from methanol. No heat needs to be added during the flash evaporation process. The pipe diameter does matter, but the pipe diameter from one tower to the two tanks doesn’t change, right? The change in pipe diameter to the flash tank corresponds to the phenomenon of sudden expansion of a pipe as described in chemical engineering principles, resulting in a decrease in pressure. The dissolved gas components of methanol in the two flash tanks are different. Dissolved gases release heat, while desorbed gases absorb heat
This post was last edited by Ye Xiang on 2016-9-22 at 13:52. So after the solution is flashed, the desorbed gas escapes from the methanol; both the gas and the liquid absorb heat, so their temperatures should decrease as heat is taken away from the liquid. Their temperature points are on the main pipeline leading to the distillation tower after passing through the control valve. I took a close look – the pipe diameters differ after the control valve: it’s thicker for sulfur-free fluid. Therefore, the temperature of the methanol coming out of the sulfur-free methanol flash tank is lower than that of the methanol coming out of the sulfur-containing methanol flash tank. Also, you mentioned that the gas components dissolved in the methanol differ between the two flash tanks – is this related to it? Since what mainly flashes inside the flash tanks is CO and H2, H2S hardly flashes there at all. The flashing of H2 is exothermic
This post was last edited by 420574713 on 2016-9-22 at 14:50. Since the gases dissolved are different, the temperature of the methanol-rich stream is also different! The diameter of the pipes leading to the two flash tanks affects the pressure drop during flashing; give this an excellent rating!