What consequences can excessive desorption in the desorption tower have for the posterior and anterior pathways?
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As the title suggests, what consequences can excessive or overdone desorption in the desorption tower have for the posterior and anterior pathways? Discussion is welcome.
A couple of days ago, we analyzed the situation where excessively high temperatures at the bottom of the tower led to an excessive amount of gas being released. This resulted in an excessive flow of rich gas entering the absorption tower, preventing the absorbent from flowing properly. As a consequence, the absorption tower became full, and the rich absorbent oil containing light components ended up in the distillation tower, causing the pressure in that tower to rise sharply while the pressure difference between the two tanks dropped significantly! The amount of gas used for analysis was adjusted in a timely manner to reduce the absorption dose, thereby preventing the accident from worsening further!
I’ve also encountered the situation mentioned on the 2nd floor. The purpose of controlling the bottom temperature of the desorption tower is to control the quality of the gas (dry gas) and liquefied gas. It’s simply that the quality of C3, C4, and C5 in dry gas must be satisfactory, and the quality of C2 in liquefied gas must also be satisfactory. A lower bottom temperature in the desorption tower helps to reduce the C3 and higher components in the dry gas. But it is not beneficial for maintaining stable pressure in the stabilizer tower. If the temperature in the desorption tower is too high, excessive desorption occurs; this phenomenon mentioned above appears when the processing volume is high or the unit is operating at full capacity. It also affects the liquefied gas yield, as all of the liquefied gas ends up in the dry gas.
The absorbent oil rich in light components is fed into the distillation tower, causing the pressure in the tower to rise sharply. I can’t understand this; it seems that the temperature in the distillation tower should drop significantly, the amount of primary gasoline should increase, and the pressure shouldn’t change much
It is believed that this is because the reabsorption tower absorbs mostly liquefied gas, and once this gas enters the distillation tower it vaporizes and accumulates at the top of the tower, causing the pressure to rise
Can light diesel absorb liquefied gas?
Sure, just make sure there aren’t too many light components inside
Under normal production conditions, when excessive desorption occurs in the desorption tower, first, the flow rate of the desorbed gas increases; this in turn leads to incomplete absorption in the absorption tower, resulting in excessive levels of C3. The lean gas then enters the reabsorption tower, causing the dry gas to contain high levels of hydrocarbons, and the product becomes unqualified. Secondly, due to excessive parsing, the feed to the stabilizer tower will decrease, resulting in a lower liquefied gas yield.
Analysis shows that the temperature at the bottom of the tower is high, the pressure in the stabilizer decreases, and the amount of liquefied gas reduces. The dry gas volume increases, and the dry gas C3 does not meet the specifications. Analysis: Low temperature at the bottom of the tower, rising pressure in the stabilizer; liquefied gas C2 does not meet specifications