The initial high-pressure value while driving rose to 147 kilograms after 40 minutes
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During our initial startup, we noticed that the system pressure rose rapidly. The high-pressure relief valve closed within half an hour (because liquid was being discharged through it). At two different measurement points beneath the high-pressure scrubber, the liquid temperature was around 170 degrees Celsius. The ammonia spray temperature was low—only 80 degrees Celsius. Initially, there was no temperature difference in the high-pressure trim water. However, just as we were about to shut down the system, a temperature difference suddenly appeared in the trim water, and its temperature rose rapidly. Meanwhile, the system pressure also increased quickly; it reached 147 before we were forced to halt operations. Preliminary analysis suggests that blockage occurred in the liquid drainage line beneath the high-pressure scrubber, leading to accumulation of liquid within the tower. After clearing this blockage, the system operated normally upon restart. How can such problems be prevented? Let’s discuss this: our system only starts working after the vehicle has been parked for over half a month
Reply to 1# zhangkai0078: 1. Is it possible that CO2 is leaking through the liquid return pipe of the high-pressure washer? 2. The liquid ammonia ejector is not functioning properly and fails to draw liquid from beneath the high-pressure washer.
Reply to 3# zhangkai0078: Could you please describe in more detail how the check is performed? If there is a blockage in the liquid outlet of the high-pressure washer, the temperature of the liquid phase should not reach 170 degrees. Based on the poster’s description, it is more likely the CO2 leaking in from the ammonia injection pipe, as mentioned above. After feeding, the liquid in the high-pressure washer wouldn’t drain; it filled up to the gas-phase inlet pipe. As a result, liquid came out from the high-pressure vent valve. If the liquid downflow pipe is blocked, gas still enters the high-pressure scrubber through the gas phase pipe of the synthesis tower, and no liquid will come out of the vent valve. Later, when a liquid level was formed at the bottom of the synthesis tower, sealing the ammonia injection pipe, the high-pressure scrubber started to operate, resulting in a temperature difference in the adjusted water. However, at this time, gas flow in the high-pressure system was impaired (liquid was present in the pipe from the gas phase of the synthesis tower to the gas phase of the high-pressure scrubber), and the high-pressure vent valve was also closed; as a result, the pressure in the high-pressure system rose rapidly. The overpressure in such cases is quite dangerous.
The suction line is blocked, because the temperature after the injector is only 80 degrees; clearly, no liquid is flowing or the amount is very small.
For driving, a ammonium pump is used first! How can there be CO2 leaking from the ammonia suction pipe? Now, we need to consider this issue. How should the problem mentioned upstairs be handled? After parking the tower, we installed blind flanges at the ammonia injection inlet and at the material return point, and then used a high-pressure pump to inject liquid into the high-level washer. We did this only once, and the water went straight up; therefore, we are still wondering whether there might be a blockage preventing the liquid from flowing down The situation you describe really reminds me of when we are driving! Also, if there are no issues with the liquid flow from the high-pressure washer, then won’t the water pumped in by the ammonium pump come out through the vent valve of the synthesis tower? If there is air leakage, how should it be dealt with?!
So what was the liquid level in the synthesis tower at that time? Was a radar level gauge used? When did you start using the system? I see you said it was for basic driving. The new systems these days don’t have high-pressure vent valves; instead, they have a vent valve at 4 bar. If the relief valve is discharging liquid, that means the synthesis tower is already full of liquid.
The high washer is empty before feeding, and the coil tubes must be filled after starting the ammonium formate pump for liquid to flow. Our high-efficiency washer’s tube bundle plus head occupies a space of just over 1 cubic meter; around 5 cubic meters of water are added, and it takes ten to twenty minutes for the liquid to fill the entire space. That’s why we need to flush the suction pipe with fluid when driving the empty tower.
May I ask, how long does it take to start the ammonia pump after installing the ammonium acetate pump? Start now, or should I wait a few minutes?
Reply to 7# Cangmang: No, we drive the vehicle after parking it for a long time. This feature wasn’t included in the initial design; it was an additional vent valve that was added later. It’s impossible for the synthesis tower to be filled with liquid just 40 minutes after starting operation
Reply 9# cthlj2007: It’s about three or four minutes after starting the ammonium carbonate pump! I wasn’t there to watch while driving; when I checked later, I saw that the temperature of the liquid flowing from the washer didn’t change