The role of intercooler in catalytic cracking gas compressor
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For catalytic cracking units, early gas compressors did not have intercoolers. The outlet temperature is around 180 degrees. Higher temperatures not only easily cause gas decomposition and increase coking tendency, but also increase the power consumption of the air compressor. After adding an intercooler, part of the C5 and C6 components can be condensed, reducing the weight flow rate of the compressor in each section behind the cooler and saving power consumption.
There is a gas-liquid separator behind the cooler, which is to prevent the secondary inlet of the air compressor from carrying liquid. It is a rich gas compressor. As the name suggests, it compresses rich gas. If there is liquid, wouldn't something happen?
Continuing from the topic on the second floor, the gas-liquid separator behind the cooler has two channels at the bottom.: All the way to the gas-liquid separation tank after the compressor, and all the way to the gas-liquid separation tank at the top of the fractionation tower before the compressor. Could you please discuss the purpose of this setting?
1. Cool down 2. Reduce liquid entrainment 3. Reduce energy consumption 4 Disguised buffering
The main purpose is to reduce the load on the second stage of the air compressor and improve the working efficiency of the air compressor. The other is to reduce the liquid in the second stage, which is C5.
The original poster's problem is just like what was said on the second floor. The main reason is that there is no liquid in the secondary compression. This is how I understand the question on the third floor. Whether the compressed condensate is primary or secondary, it is generated by rich gas and has been sent to the absorption stabilization system for separation. Why are some sent to the liquid separation tank before the compressor and some sent to the back of the compressor? Under normal working conditions, it is sent to the liquid separation tank after the compressor. Because it is sent forward to the liquid separation tank in front of the compressor, the compressed rich gas will volatilize when it reaches the low-pressure tank and re-enter the compressor for compression, which increases the load of the compressor, reduces the efficiency of the compressor, and also causes fluctuations in its reaction pressure. However, when an accident occurs in the absorption stabilization system or the liquid separation tank after the compressor, the condensate from the first-level compressor cannot be sent to the liquid separation tank after the compressor. At that time, it will flow back to the liquid separation tank before the compressor.