How to determine if a transformed heat exchanger has an internal leak?
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How to determine if a transformed heat exchanger has an internal leak? Dear experts, please share your valuable insights based on your own experience and methods!
Comparison of CO content in imports and exports； Comparison of CO emissions at each outlet; a large amount of CO leakage will cause the levels to rise.
1. The feedwater volume to the highly variable drum increases, making it difficult to maintain the drum liquid level. 2. The low-temperature inlet temperature decreases, and the pressure difference in the low-temperature converter increases. 3. System resistance increases. 4. The low-moisture level rises rapidly.
Available from temperature\wastewater volume\gas composition
I think the person on the second floor is right.
① In the sampling and analysis comparison of carbon monoxide levels at the exit of the medium-conversion furnace and at the inlet of the low-conversion furnace, if there is an internal leak, the carbon monoxide level at the low-conversion furnace inlet will be higher than that at the medium-conversion furnace exit. ②The temperature of the low-temperature shift catalyst bed will rise, the load at low temperature shift increases, and the outlet carbon monoxide level goes up (based on operational experience, it feels more difficult to adjust than under normal conditions).
A comparison of the CO levels at the inlet and outlet of the gas after heat exchange can be made; if the level at the outlet is significantly higher than that at the inlet, it indicates a severe leak
First, it is necessary to determine from which side the heat exchanger is leaking and to which side. In our plant, boiler water leaks into the conversion system, which increases the water-vapor ratio; the most noticeable effect is an increase in the decarburization heat load and a rise in temperature, which may cause the safety valve to activate.
The situation upstairs is the same as ours; the change in operating conditions in such cases is very noticeable, and analysis should be carried out when there is slight leakage
What the user above mentioned is quite comprehensive; I’ll add a bit more. Ammonia synthesis involves many heat exchangers, and it would be better to establish a system for detecting leaks – to regularly check these heat exchangers and other related equipment for leaks and keep records of such inspections.
Generally, the pressure of the boiler feedwater on the tube side is much higher than the pressure of the process gas; as a result, leakage from the tube side to the shell side occurs, which means that the water-to-carbon ratio of the process gas entering the low-temperature conversion section increases significantly. This in turn leads to an increase in the temperature of the low-temperature conversion bed and an increase in the load on that unit. If it is a minor leak, samples can be taken for analysis, and a judgment can be made based on the CO levels at the inlet and outlet of the heat exchanger. It can be determined from the carbon removal balance: if there is an internal leak, the carbon removal system will become disrupted, which indicates a serious leak! Our factory has a similar situation.