Our Coker Unit running daily basis is 24.5MB.
Before this we did not having this experience after our UPS System is Totally Fail and DCS also cannot function.
After we completed prepare a shutdown and clean everything we manage to start-up the unit.
From my point of view, this start up is totally different. Especially after establish flow during hot circulation and than we proceed backwarming drum.
First indication we get, we managed to get backwarm temperature before send to fractionator less than 10 minitues without pitch butterfly valve more, just maintain it by 90% Opened is enough (Monitor from outside same reading with DCS).
When we routed our backwarming to fractionator, the temperature for backwarming gradually decrease until reach below than 170 C.
We managed to get unit flawless start up smoothly. Only the big changes on the fractionator pressure. Before this preesure is indicate less than 1.9 kg/cm2 and drum pressure is less than 2.2 kg/cm2. Now the pressure of parameter is big changes for fractionator 2.6 kg/cm2 (RV Setting is 3.2kg/cm2) and Coke drum 3.0 kg/cm2 (RV Setting is 4.05kg/cm2)
Question….From your opinion, expecience and sharing?
1. It is possible cause Butterfly Valve Failure…. or internal part damaged…?
2. This is cause of Wet Compressor limitation…..?
3. AFC Plugged….?
4. Overhead line on the vertical session is badly plugged cause of UPS and Power Failure.
Any solution to share…