Why must the pressure be reduced first when the temperature in the synthesis tower drops?
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????? Who can tell me the benefits of lowering blood pressure?
Well, reducing the voltage is to make it easier to heat up the electric furnace
It’s because when the temperature drops, it is first reflected in the pressure; the pressure must be too high. With such a large flow rate, the heating furnace also operates slowly. If the pressure were lower, the temperature could rise more quickly
When the temperature in the synthesis tower drops, if gas is not cut off to reduce pressure, the flow rate of the circulating gas during the heating process becomes too high; the power of the electric furnace is insufficient, making it difficult to raise the temperature； Furthermore, even when the temperature reaches the active level, during the pressure increase process, the high pressure leads to intense reactions, making it difficult to control the temperature, and overheating is likely to occur.
After the temperature drops, the ammonia synthesis reaction cannot proceed; in other words, the gas supplied into the circuit cannot be used to produce ammonia for separation, which causes the pressure in the circuit to rise sharply. To ensure safety, the supply of gas should be stopped at this point, and the system’s vent valve should be opened to release pressure. If toxic gases enter the synthesis circuit, the system also needs to be purged, and venting is necessary as well. During the process of raising the temperature again, if the pressure is too high, the volume of gas circulating will increase, weakening the effect of the electric furnace and thus hindering temperature elevation.
When the temperature in the synthesis tower drops, the ammonia synthesis reaction deteriorates and the system pressure rises; releasing air to reduce pressure ensures safety； After the temperature drop, the higher the pressure and the greater the space velocity, the faster the catalyst bed temperature will drop ； After the temperature drops, it is necessary to raise the temperature again; in order to reduce the load on the electric furnace and lower electricity consumption, it is also necessary to lower the voltage
The reason for the temperature drop is ultimately due to an imbalance between the heat generated by the reaction and the heat carried away by the circulating gas flow. Venting can reduce the volume of circulating gas, which is equivalent to lowering the load on the synthesis tower
At low temperatures, the reaction efficiency is poor; reducing pressure is done to lower the space velocity and prevent too rapid a drop in temperature. Another advantage is the faster heating rate, which helps improve the utilization of thermal energy in electric furnaces.
After the synthesis tower loses temperature, the heat of reaction decreases; high pressure and a large circulation volume accelerate this temperature drop. Reducing the pressure is intended to decrease the circulation volume and thus halt the temperature drop in the tower as quickly as possible. Similarly, lowering the pressure helps to raise the temperature of the electric furnace, allowing production to be resumed swiftly.