Weekly Topics on Ammonia Synthesis Knowledge

This post was last edited by Chemical Gas Purification on 2010-11-28 at 11:27. 1. The end of the reduction process does not mean that the reduction is complete; the degree of reduction can still be increased during production. 2. The production load is low, and the catalyst temperature is relatively low, which facilitates the stability of the active centers and prevents them from aggregating and growing, thus extending the service life of the catalyst. If the temperature is too high during the reduction process, polymerization is likely to occur, reducing the number of active centers. Similarly, during the production process, one should not easily increase the temperature to boost activity, as this is detrimental to the catalyst’s lifespan.

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This post was last edited by Chemical Gas Purification on 2010-11-28 at 11:26. The low-load operation period is usually 72 hours. This low-load phase is necessary so that the catalyst, right after being reduced, cannot have its operating intensity increased to maximum levels immediately; it is intended to ensure the stability of the catalyst’s activity throughout its subsequent use and to prevent a reduction in its service life. Just like a person, one cannot expect them to take on a heavy workload from the start – the intensity of work should be increased gradually, otherwise overexertion can have permanent effects on future performance.

Just after the ammonia synthesis catalyst has been reduced, in order to maintain its activity at low temperatures, the temperature and pressure are not raised to normal levels; the reduction is not complete, and full reduction takes a considerable amount of time. Therefore, during the initial stage of operation of the catalyst, it continues to be reduced, operating in a state of both production and reduction； Therefore, it needs to operate at low load for a period of time. Generally, the light-load time is required to be 24 hours. (The light-load time generally varies depending on the device and catalyst, and is not very definite.)

1. The low-load period is generally 48–72 hours. 2. Low load is applied to stabilize the lattice of the catalyst right after it has been reduced, preventing it from changing rapidly; this helps to maintain the maximum level of catalyst activity and ensures that the catalyst’s service life remains unchanged over time.

[Allow further reduction by the catalyst to make the resulting crystals more stable.] Generally, it is generated over a week at low load.

I’m not sure, so I’d appreciate some advice. I’m a new operator at the factory

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This post was last edited by Chemical Gas Purification on 2010-11-29 at 11:16. The reduction of ammonia synthesis catalysts occurs in three stages (initial reduction stage, main stage, and final stage). The main purpose of the final stage is to ensure that the most difficult-to-reduce parts are reduced as thoroughly as possible, and a high temperature should be maintained during this stage. Since most of the catalyst has been reduced by the end of the reduction process, the reaction is quite pronounced and the temperature rise in the bed is significant. In order to ensure that the temperature at all points in the bed reaches and stays close to the final reduction temperature, the pressure can be reduced to around 8.0 MPa, thereby minimizing the temperature increase caused by the reaction. The ammonia synthesis catalyst that has just been reduced has high activity, so it is necessary to operate it under light load for a period of time; this helps to prevent premature aging of the catalyst and extends its service life. Generally, operation under low load lasts for about 5–7 days.