Condensing temperature of ammonia

The condensing temperature of ammonia not only affects the content of ammonia in the converter inlet, but also affects the stability of the temperature in the catalyst bed. With the fluctuation of 1°C in the condensing temperature of ammonia, the temperature of catalyst bed will fluctuate by 3-5°C. Hence, the condensation temperature of ammonia is a matter of concern in practical operations. 

It should be pointed out that the condensing temperature of ammonia at the outlet of converter changes with the synthesis pressure, which makes the investment of... 

The process mentioned is about the cooling purification process. For most of modern ammonia plants, it is more popular to use the thermal purification method. In the thermal purification process, the final purification is methanation, and the content of inert gas (CIH-I-Ar) is usually higher. The increase of the inert gas content will reduce the concentration and the net value of the outlet ammonia. The research results show that, while the inert gas content increases by 1%, the net value will reduce by about 0.3%-0.4%. In the condition No. 2 of Table 9.5, if the inert gas content increases to 6%, the net value will decrease from 10.69% to 9.49%. Then the amount of inlet gas of converter and the catalyst volume are 64.45 x 10 m h and 107.4 m , respectively. If the inlet concentration of ammonia of the converter is reduced to 2% (condensing temperature is about —30°C), the net value of ammonia will reach 11.15%, and the amount of inlet gas of converter and the catalyst volume are 54.85 x 10 m h and 91.4 m , respectively. It will be seen from this that, for the thermal purification process, it is necessary to limit the inert gas content below 6%-8% and to decrease the condensing temperature of ammonia to about —30°C. 

---