Disbalance between the hydrogen-to-nitrogen ratio in the fresh gas and that in the recycled gas
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In ammonia synthesis, an imbalance in the hydrogen-to-nitrogen ratio leads to a high hydrogen-to-nitrogen ratio in the fresh gas, resulting in increased system pressure and reduced current in the circulator; a low hydrogen-to-nitrogen ratio, on the other hand, causes a larger pressure difference in the system and an increased current in the circulator. In short, both high and low levels have a significant impact on the synthesis reaction. So what about the hydrogen-to-nitrogen ratio in the recycle gas? Is it the same as in fresh air?
The hydrogen-to-nitrogen ratio in the recycled gas differs from that in the fresh gas; the trends are similar, but there is a certain time lag depending on the size of the system – larger ammonia synthesis systems exhibit a longer lag in changes in recycled hydrogen, while smaller systems have a shorter lag.
What is the hydrogen-to-nitrogen ratio in the circulating gas? Is it the same as in fresh air? The hydrogen-to-nitrogen ratio in the recycled gas is different from that in the fresh gas, and the two are closely related to each other. During the actual adjustment process, if the hydrogen-to-nitrogen ratio of the recycle gas is high, the hydrogen-to-nitrogen ratio of the fresh gas must be reduced (taking into account the hydrogen recovered). Conversely, the same principle applies to maintain the hydrogen-to-nitrogen ratio at an optimal level.
When the hydrogen-to-nitrogen ratio in the fresh gas is imbalanced, excess hydrogen or nitrogen accumulates in the system, thereby altering the hydrogen-to-nitrogen ratio of the recycle gas and affecting the synthesis reaction. So, in your words: \"A higher hydrogen-to-nitrogen ratio results in increased system pressure and a reduced current in the circulation pump; a lower hydrogen-to-nitrogen ratio leads to a larger pressure difference in the system and an increased current in the circulation pump.\" ”It’s not exact.
So what you’re saying is that the hydrogen-to-nitrogen ratio in the fresh gas should follow the same pattern as that in the recycled gas?
The hydrogen-to-nitrogen ratio in the fresh gas is the same as that in the recycled gas, right? The hydrogen-to-nitrogen ratio of the gas entering the synthesis tower is generally between 2.8 and 3.0. After part of the reaction takes place, the hydrogen-to-nitrogen ratio of the gas exiting remains unchanged; only their amounts differ from those before the reaction, while their ratio stays the same.
What directly affects the operating conditions of the synthesis tower and the power of the circulator is the hydrogen-to-nitrogen ratio of the recycle gas, rather than the hydrogen-to-nitrogen ratio of the fresh gas as stated by LZ. Fresh gas is used as a feed material for the synthesis tower, and its hydrogen and nitrogen contents are adjusted based on those of the recycled gas. When the hydrogen-to-nitrogen ratio in the recycled gas is out of balance, it is necessary to readjust this ratio by modifying the hydrogen and nitrogen proportions in the fresh gas. For example, if the hydrogen-to-nitrogen ratio in the recycled gas is low, then the hydrogen content in the fresh gas needs to be increased, and vice versa. The hydrogen-to-nitrogen ratio is a relative concept; therefore, the changes in the hydrogen-to-nitrogen ratio of the fresh gas and that of the recycled gas should be said to be synchronous rather than identical.
The hydrogen-to-nitrogen ratio of the recycle gas is primarily regulated by the hydrogen-to-nitrogen ratio of the fresh gas.