How to balance the medium-pressure steam network when reducing the speed of the syngas compressor?
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For the Kellogg process large-scale ammonia synthesis plant, we would appreciate it if you could discuss how to balance the 38-kilogram steam pipeline network when the syngas compressor 103-J slows down, so as to maintain stability in this pipeline network and prevent an emergency shutdown due to an improper water-to-carbon ratio
The reduction of the compressor’s load should be carried out in stages. After the speed is reduced slightly and the pressure in the pipeline network rises, the boiler and the pipeline network need to be adjusted; once the pressure stabilizes, another portion of the load can be reduced. Throughout this process, coordination among all team members is essential, and it is important to proceed slowly and without haste, allowing the compressor to reduce its load gradually and smoothly.
The main approach is to control the pressure in the pipeline network by properly regulating the vent valve for medium-pressure steam. Notify the steam withdrawal outside the area in a timely manner.
When 103-J reduces its speed, it lowers the setting of SIC-301, which results in a decrease in the amount of steam consumed by 103-J. This leads to pressure buildup in the high-pressure steam system, causing the pressure in the high-pressure steam pipes to rise significantly. As the flow rate of steam decreases, it is easy for the high-pressure steam coils to overheat. At the same time, due to the low air intake of 103-J, the amount of medium-pressure steam discharged also decreases, causing the pressure in the medium-pressure steam pipeline network to drop rapidly. It is necessary to promptly open the high-pressure steam pressure relief valve PCV-13 in order to reduce the pressure in the steam drum, increase the pressure in the medium-pressure steam network, boost the flow rate of high-pressure steam, and ensure that the high-pressure steam coils do not overheat. At the same time, if the medium-pressure steam pipeline network is still under pressure, contact the external supply to increase the steam delivery volume. If the temperature of the high-pressure steam coil is high, the air ducts in the furnace convection section can be activated for a while. Of course, an auxiliary boiler load can also be added to achieve balance. In summary, it is necessary to ensure that the high-pressure pipeline network does not experience overpressure, that the medium-pressure pipeline network does not suffer from underpressure, and that the high-pressure steam coils do not reach excessive temperatures.