Issues regarding the feed gas compressor
Thread Content
In the production of hydrogen from coking dry gas, there is always liquid level in the inter-stage separators of the feed gas compressors; even after the liquid is drained, it builds up again. The level gauges are functioning properly, and there are no leaks in the inter-stage coolers, so equipment-related problems can be ruled out. At first, I thought that the coking dry gas contained liquid, so I had someone go to the raw gas buffer tank located before the raw gas compressor to remove the liquid from it. Not much liquid was removed in this process. Another thing is that during the hot days, the liquid level in the inter-stage separator rises more quickly, while on cooler nights it rises more slowly; sometimes, even after all the liquid has been drained, the level doesn’t continue to rise. This problem has puzzled me for a long time, and I hope that fellow experts can help me figure it out, preferably regarding coking dry gas. I already understand six out of the seven aspects related to coking processes.
Coking dry gas needs to be desulfurized before being used as a raw material; otherwise, sulfur corrosion will be severe. You can analyze the components of the liquid to determine what they are, and then investigate the cause.
It is mainly related to the temperature of the dry gas. At high temperatures, the condensate is carried to the compressor before it has time to condense, where it is then condensed in the intermediate liquid separation tank. If the temperature is low, it will have condensed before reaching the compressor, so it won’t make it into the compressor.
We also have this problem; I think it’s due to the presence of C3 and C4 in the raw materials
Please provide the gas composition, as well as the pressure and temperature parameters at each stage, so that it can be determined whether the gas has liquefied between the stages
What liquid is carried? Does dry gas carry liquid ethanolamine?
Analyze its composition to determine whether there are light hydrocarbon components, which will condense after compression and cooling
Please provide the gas composition, as well as the pressure and temperature parameters at each stage, so that it can be determined whether the gas has liquefied between those stages. This approach is more reliable, as the temperature values and the presence of liquid in the system are indeed confusing! ! ! It seems more logical that the temperature is lower and there is severe liquid presence…
It is recommended to first test the liquid components in the machine room’s liquid separation tank, to understand the composition of the liquid, and then determine what substance it is based on those components. We encountered this issue before as well, with the coking dry gas containing liquid, and the liquid in question was ethanolamine. It was determined that there was a problem during the dry gas desulfurization process, so the coking unit was contacted to adjust the desulfurization system.
If an amine solution is used, it should be the level in the inlet demister tank that rises, rather than the level in the inter-stage demister tanks.