Problem with the refrigerant compressor surge curve diagram
Thread Content
A section of the operating point often fluctuates around the surge curve! Or it may cause the surge valve to open automatically online. The two-stage operating point always exceeds the compression ratio operation! How can we get to the safe area? What causes this situation
Several treatment methods: 1 is to open the compressor return line, which will cause the operating point to shift to the right and return to a safe range; 2 if the original design’s surge line is inaccurate, it can be redrawn through experiments while the system is in operation; 3 is to check whether the compressor’s process pipelines are fully open, as insufficient flow may indicate issues with the system
Check whether the inlet flow is sufficient; if not, add air. If sufficient, increase the opening degree of the anti-surge valve appropriately while ensuring adequate flow; the compressor speed can also be reduced by having the turbine drive it, or a frequency-control motor drive it, or using a unit with a coupler.
We are a natural gas plant, and the refrigerant compressors use five different types of refrigerants! Nitrogen, methane, propane, ethylene, paraffins; the compressor inlet pressure is around 180, with a flow rate of 140 tons per hour; the outlet pressure at the second stage is 3800 kp
The first addition is one that we have experimented with! As long as the surge valve is opened, the operating point will remain within the safe zone, further away from the surge line than before.