Water in the compressor inlet issue
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The compressor in our unit is reciprocating, and it is necessary to drain the liquid (which mainly consists of oil and gas) from the first-stage outlet to the separation tank at the second-stage inlet. Would providing heat tracing for the separation tank located before the compressor inlet reduce the frequency of such drainage? Will that have an impact on the compressor?
This post was last edited by lovestory on 2012-3-30 at 15:36. Since the liquid separation tank focuses on handling oil and gas, adding heating can reduce the frequency of liquid discharge. We add another tank to which the liquid from the separation tank is regularly transferred; it is then sent out. Of course, these are all control valves, not manual ones.
Theoretically, doing this is useless. The presence of water in the inlet gas did not result in liquid slugging or a sudden drop in temperature, indicating that the water was steam present in the feed gas. The inlet heating serves no other purpose beyond raising the temperature of the inlet gas. In principle, the lower the inlet temperature, the higher the pumping efficiency; this is also why production is higher in winter than in summer. Adding heating to the liquid separation tank in front of the inlet, as you mentioned, will result in a poorer separation performance by the separation tank; more liquid will remain after the first stage of separation. This not only fails to solve the problem but actually makes the situation worse. By the way, what is the inlet temperature in winter? The temperature at the entrance of our plant is below zero, resulting in icing on the filters in the inlet pipelines. The measure taken was to insulate the pipeline from the gas holder outlet to the compressor inlet, but no heating was installed. I’m not sure if you’re satisfied with the answer
It’s not a good idea. Firstly, there are requirements regarding the temperature of the gas entering the compressor; a high temperature affects the pumping volume, and the outlet temperature also needs to be increased. Secondly, heating the tank to the vaporization temperature of water requires a large amount of energy, and the vaporized water also takes up space in the compressed gas, affecting the volume of gas that can be pumped. The water that vaporizes again will cause corrosion to the carbon steel components of the compressor (this is particularly severe in carbon dioxide compressors). Therefore, if the moisture content in the medium is high, it is necessary to increase the capacity of the separation equipment, use low-temperature separation, or increase the frequency of drainage.
If the liquid is not drained in a timely manner, fluid hammering can occur, and in severe cases, the cylinder may be damaged. The connecting rod is damaged.
Before pressure reduction, there are multiple rows of separation tanks… When the gas containing oil and gas is compressed, water separates out quite clearly
Adding heat tracing is not good； Firstly, it does not work; secondly, as the temperature rises, the exhaust temperature increases, which leads to poor heat exchange and results in a higher level of moisture at the outlet.
If temperature has no impact, you can remove the cooler at the primary outlet; this way, there will be no water flowing from the primary outlet to the secondary inlet, provided that the temperature remains within the compressor’s set range.
It seems from the OP’s meaning that it’s a model without a cooler? There is no cooler, but some oil and water accumulate in the separator. The presence of oil may be due to lubrication with oil in the cylinders, or it could be oil present in the gas. If the gas is clean, heat can be added to prevent water from condensing; anyway, the oil can still serve as a lubricant in the next stage. Water forms whenever the temperature drops, so it must be removed. However, the absence of a cooler means that cooling isn’t necessary. Theoretically, adding heat could prevent water from condensing, but this approach seems to have more disadvantages than advantages. Does the poster think that working frequently with liquids is a heavy workload? If there is a cooler, then it’s completely unnecessary.
Every class has to line up once; it’s not that troublesome, but I was wondering if there’s any good way to avoid bringing water
In winter, the inlet temperature is usually above 1° and never drops below 0°; this is probably related to the temperature of the circulating water