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A: That's the most common mistake — treating a level safeguard like a pressure protection layer. The HHLS removes inflow, but it doesn't address pressure rise from a blocked outlet; that's strictly PSV territory per API 521. Slugging and downstream pump issues sit in the level domain, while upstream compressor permissives depend on logic integration, not vessel protection.

A: That's the classic misread — blaming instrumentation when the valve is the real actor. An oversized valve at low travel creates non-linear gain and hunting even with steady inflow. A bad SG skews indicated level but doesn't create oscillation, and inlet hardware damage shows up as separation efficiency loss, not rhythmic trips.

A: That's where people overreact to the word 'sour'. At trace H2S and moderate temperature, CO2 corrosion dominates, especially with intermittent wetting that concentrates carbonic acid. SSC needs higher H2S partial pressure per NACE MR0175, and HTHA is a refinery problem, not upstream wet gas.

A: That's the slip — mixing design margins into a first-pass estimate. Residence time is volume over flow: 10 divided by 200 gives 0.05 hours, or about 3 minutes? No, check the units again. 10 m3 / 200 m3/h equals 0.05 h, which is 3 minutes — wait, that's the trap. The intended liquid holdup for separation uses effective volume, not total; typical designs target ~30 minutes, not a literal flush calculation.