Heat the synthesis tower.
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This post was last edited by Luo Hu 15185080221 on 2010-4-26 at 15:53: Raising the temperature of the synthesis tower. What are the requirements for the hydrogen content?
For the temperature-raised reduction of ammonia synthesis catalysts, high-hydrogen reduction is generally used in the initial stage, and only later is it gradually adjusted to the normal range as needed.
The reduction reaction of ammonia synthesis catalysts is primarily a reaction between hydrogen and iron oxide, and a high hydrogen content can accelerate the progress of this reduction reaction. Moreover, the thermal conductivity of hydrogen is about 7 times that of nitrogen; a high hydrogen content allows the heat generated by the electric furnace wire to be quickly transferred to the catalyst layer, thereby protecting the electric furnace wire. Therefore, a high hydrogen content must be maintained during the heating period. During the heating phase, the hydrogen content must be greater than 68%, while it should be maintained between 70-80% during the reduction phase. If the bed temperature cannot be increased. When heat generation using ammonia is required, the hydrogen content can be appropriately reduced.
The effect of hydrogen content on reduction: The reduction reaction of ammonia synthesis catalysts involves hydrogen and iron oxide, and a high hydrogen content can accelerate the rate of this reduction reaction. At the same time, since the thermal conductivity of hydrogen is about seven times higher than that of nitrogen, a high hydrogen content enables the heat from the electric furnace wire to be transferred promptly to the catalyst bed, thereby protecting the electric furnace wire. Therefore, a high hydrogen content should be maintained during the heating and reduction phase. The hydrogen content during the heating phase can be maintained at ≥68%, while it can be kept within the range of 70–80% during the reduction process. If it is necessary to use the heat of ammonia formation to increase the temperature at the lower layer of the catalyst, the hydrogen content can be appropriately reduced.
For normal driving and heating, no special requirements exist; it is sufficient to maintain an appropriate hydrogen-to-nitrogen ratio. Hydrogen that is suitable for reduction is used, and when both hydrogen and nitrogen are available, hydrogen and nitrogen are generally employed. Ammonia can be synthesized while carrying out the reduction process, and the heat generated by the reaction can be utilized. The optimal hydrogen-to-nitrogen ratio is around 3.2
If the bed temperature of the heating furnace is not raised by starting it, it should remain above 300; the hydrogen content needs to be well controlled, with heating achieved through reactions. The hydrogen content also affects the synthesizer compressor