Weekly topic for ammonia synthesis production: How to properly control the temperature of the synthesis tower during initial startup
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This post was last edited by Yan Qiusheng on 2011-7-16 at 21:22. During the initial startup, the catalyst’s activity was too high, and normally the gasification furnace operates with two units in use and one as a backup; it’s likely that only one unit was in use during the initial startup. How to adjust the temperature of the synthesis tower when the gas volume is low and the catalyst activity is too high.
When operating the plant initially, it is crucial to control the circulation rate and the power of the electric furnace; meanwhile, the reaction intensity can also be regulated by appropriately reducing the hydrogen-to-nitrogen ratio, thereby enabling better control of the tower temperature. Later on, cooling gas can be used for adjustment.
It mainly relies on the control of your circulation volume, as well as the bypass lines of the boiler feedwater preheater and those of the heat exchanger inside the tower; however, the range of adjustment must not be too large!
The heating rate of the synthesis tower must be well controlled.
I’m a newcomer. Apart from gaining familiarity with the manufacturing processes, my focus is mainly on testing instruments and control instruments.
I agree with what was said on the 2nd floor: in the early stages of reaction in the synthesis tower, heat is supplied from the outside to reach the required reaction temperature, while in later stages the reaction temperature is greatly influenced by the heat generated by the reaction itself. Therefore, I think it’s better to control the temperature by adjusting the hydrogen-to-nitrogen ratio. Another issue is heat exchange; there are probably many other problems as well. I look forward to advice from those who are more experienced
What was said on the second floor is very good: it’s necessary to control the circulation rate and the power of the electric furnace. The reaction intensity can also be regulated by appropriately reducing the hydrogen-to-nitrogen ratio. When raising the temperature, it’s important to control the speed, as this helps to better manage the temperature in the tower. Later on, the temperature can be adjusted using cooling gas.
What was said on the second floor is very good: it’s necessary to control the circulation rate and the power of the electric furnace. The reaction intensity can also be regulated by appropriately reducing the hydrogen-to-nitrogen ratio. When raising the temperature, it’s important to control the speed, as this helps to better manage the temperature in the tower. Later on, the temperature can be adjusted using cooling gas.
The key is the control of the heating rate, which can be adjusted through the flow rate and the electric furnace; once the temperature reaches the active range, attention should be paid to regulating the split gas.
Discussion on the hydrogen-to-nitrogen ratio! Learn from each other*. How to better control the hydrogen-to-nitrogen ratio? How to control it?
In normal operation, the circulation rate is very important; it is necessary to carefully inspect the valves of each circulation machine, and to conduct pressure tests on the valve flanges of all equipment pipelines to check for leaks. Before starting the vehicle, carefully check whether the switch positions of all cold shock valves are correct to prevent false flow, and inspect whether there is any internal leakage in each cold shock self-regulation system. Check the thermocouple to prevent false temperatures. Control the temperature at zero degrees, manage the system pressure, determine whether there are internal leaks in the system’s pathways, control the gas composition as well as the amount of inert gas; if the temperature is high, reduce the hydrogen content accordingly.