Shell & tube FWG vacuum low, low production, high shell temperature While running the deflector plate under

Shell & tube FWG vacuum low, low production, high shell temperature

While running the deflector plate under the demister had collapsed onto the evaporator. We opened the top cover and fixed the deflector plate where it belonged and restarted.

But we noticed that the vacuum build up was slow and when we introduced JCW, although boiling appeared to be taking place the vacuum fell and shell temp shot up to 70°C. The feed line is very hot to touch.

The production also dropped to about 350L per hour or around 8.5 T/day.

One thing we noticed was that the ejector pump discharge pressure increased from 3.2 bar to 5.5 bar after this incident. Vessel is in loaded condition and draft has not changed. All SW valves in the line are fully open.

Parameters (Present):

SW temp - 31°C

Condenser in/out - 31/43°C

Shell temp - 70°C

Vacuum - as per attached picture

JCW in/out - 82/74°C

Ejector pump pressure - 5.5 bar

Present Status: Presently FWG is stopped.