Refrigerant Compressor Antisurge Quench

[TDE1]

I have a question about antisurge systems for multistage refrigerant compressors. On smaller compressors we typically run the hot gas bypass/antisurge to the evaporator where it can be desuperheated most effectively. I am noticing on larger units (gas turbine driven) the antisurge goes directly into the suction scrubber with a quench. What is the logic behind/advantage of this? Is it for faster response and vapour return to the compresor?

Thanks in advance

 

[dcasto]

There is no Thermodynamic reasons I can see. Our 2 10,000 HP units had this along with Temperature controled propane liquid mixed with the hot gas. The anti-surge/recycle system was all within 20 feet of the compressor and the chillers were 100 feet away, so it did save a lot of line and lag time.

 

[ihg]

I have had such a system. The liquid propane spray droplets dropped out of the hot gas, and evaporated on the bottom of the pipe resulting in a half-moon layer of ice on the outside of th pipe. Then the surge problem went away, the line warmed up, and a large length of ice fell about 6 metres into the walkway. ..Mechanical design is important.