If the pressure in the low-pressure section is low, how does the pressure in the high-pressure section change?
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Dear sea friends, if the pressure in the low-pressure section of the carbon dioxide stripping process is too low, could this cause the pressure in the high-pressure section to rise?
First, let me share my own thoughts: A low pressure in the low-pressure package will certainly cause excessive condensation of the gas phase inside the high-pressure methanol cooler, resulting in less gas phase entering the synthesis tower. The decrease in temperature within the synthesis tower further reduces the rate at which methamine is converted into urea； Due to the obstruction of the reaction that uses methamine to produce urea, the concentration of methamine in the liquid phase remains high, which causes the reaction between carbon dioxide and ammonia to form methamine to proceed in the direction of methamine decomposition So the pressure in the high-pressure circuit will increase slightly?
If the pressure in the low-pressure drum is too low, gas is generated in the drum and rises; this gas condenses excessively in the high-pressure section, which means that all the heat is transferred to the cooling system of the high-pressure section. As a result, the exothermic reaction in the synthesis tower is insufficient, and the urea conversion rate inevitably decreases. If all other conditions remain unchanged, the pressure in the high-pressure system will drop
In a short period of time, the pressure in the synthesis system decreases, which increases the load on the distillation column as well as on the circulation system; this leads to overpressure in the circulation system. Over time, the pressure in the high-pressure system actually rises, creating a vicious cycle