Relationship between the external cooler temperature and the bottom temperature of the first absorption tower

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This post was last edited by ty0ty00 on 2010-6-30 22:59. In the urea process with full circulation of aqueous solutions, dimethyl ether and vapor are cooled in a heat utilization section after heat exchange, and then pass through two external coolers before entering the first absorption tower; generally, the temperature at the bottom of the first absorption tower is 1–2°C lower than the temperature of the fluid entering the tower from the external coolers. However, during the production process, it is common for the temperature of the gas-liquid mixture entering the first absorption tower from the first absorption cooler to be a few degrees lower than the temperature at the bottom of that tower. For example, if the temperature of the mixture entering the tower from the cooler is 95°C, the temperature at the bottom of the tower could be 98°C. Some say that the dimethyl liquid fails to react properly with the vaporized gas, which results in low reaction heat in the external cooler and thus a low temperature. The unabsorbed carbon dioxide then undergoes an exothermic reaction in the absorption tower, leading to this situation of opposite temperature differences. I would like to ask all the sea friends to discuss this – is that the case? Why does this phenomenon of poor absorption occur again?