【Q&A Question 131】2016.08.29
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【Q&A Question 131】August 29, 2016: Methods for dealing with hydrogen circulation carrying liquid. The answer key can be seen after responding; scoring is based on addressing the key points. Properly drain the liquid from the separator tank at the inlet of the circulation machine and from the condenser; activate high-pressure air cooler A101 to minimize the temperature after cooling, maintain the temperature difference between the lean amine solution and the circulating hydrogen, ensure the quality of the lean amine solution, and pay attention to the liquid level in the high-boiling fraction section.
First, drain the liquid from the buffer tank at the compressor inlet in a timely manner to prevent the compressor from shutting down due to interlock； In the second step, determine the cause of the liquid presence, and make adjustments accordingly ； If the temperature of the circulating hydrogen is too high, it is necessary to adjust the water flow rate in the cooler in order to lower the temperature ； If the amount of circulating hydrogen is too high, the flow rate needs to be reduced ； If the raw material contains light components, it is necessary to improve its properties promptly ； Additionally, the liquid phase may have entered the inlet buffer tank built into the compressor; once the issue causing the presence of liquid is resolved, the compressor can be switched on as soon as possible, and the standby unit should be inspected for any liquid present.
Reduce processing volume, reduce the amount of waste liquid, lower the inlet temperature of the high-pressure stream, and keep the level of the high-pressure liquid under control! Strengthen liquid cutting!
1. Strengthen liquid cutting to reduce fluctuations in the high-level liquid level, keeping the liquid level below 55%； 2. High-temperature control below 43 degrees Celsius
1. Try to reduce the temperature of the high-pressure separator. 2. Keep the liquid level in the high-pressure separator from rising too high. 3. Drain the liquid from the circulating hydrogen buffer tank in a timely manner. 4. Slightly reduce the processing capacity of the plant. 5. Calibrate the level measurement devices in the high-pressure separator and the circulating hydrogen buffer tank to ensure accurate readings
Reduce the temperature of the circulating hydrogen, increase liquid drainage, and lower the liquid level in the inlet liquid separation tank
1. Reduce the flow rate when conditions permit. 2. Add more drainage at the inlet. 3. Increase the amount of lean liquid in the circulating hydrogen desulfurization tower. 4. Lower the temperature of the circulating hydrogen
Reduce the temperature of the circulating hydrogen, strengthen the control of liquid discharge from the compressor inlet buffer tank to maintain an appropriate liquid level
1. Increase the valve opening of the pressure reducer from the hydrogen circulation machine inlet buffer tank to the cold low-pressure fractionator, and quickly adjust the liquid level in the inlet liquid separation tank to normal. 2. Pause the amine solution circulation in the cyclohydrogen desulfurization tower if necessary. Check whether the heat tracing steam at the inlet of the circulating hydrogen compressor is activated. After excluding the above factors, if the circulating hydrogen still contains liquid, the possibility of a failed defoamer screen should be considered; in emergency situations, shutdown procedures should be followed.
1. Increase the valve size of the pressure reducer from the hydrogen circulation machine inlet buffer tank to the cold low-pressure fractionator, and quickly adjust the liquid level in the inlet liquid separation tank to normal. 2. Pause the amine solution circulation in the cyclohydrogen desulfurization tower if necessary. Check whether the heat mixing steam at the inlet of the cyclic hydrogen compressor is enabled. 3. After excluding the above factors, if the circulating hydrogen still contains liquid, the possibility of a failed defoamer screen should be considered; in emergency situations, shutdown procedures should be followed.
Reduce the temperature of the high-pressure separator and enhance liquid removal in the recycle hydrogen inlet buffer tank