(Solved): Question 4 A process instrumentation diagram for a flash drum is shown in Figure Q4. Steam is conden ...

Question 4 A process instrumentation diagram for a flash drum is shown in Figure Q4. Steam is condensed in a steam coil to vaporize a portion of the liquid feed, and the liquid product is removed by a pump. There are five control valves for the steam flow, vapor product, liquid product, feed flow, and steam chest (which allows the steam chest to be rapidly evacuated in emergency situations). Determine whether the five valves should be Fail-Closed (F/C) or Fail-Open (F/O) for safe operation and justify your answers. Given that the safest conditions are achieved by the lowest temperature and pressure in the flash vessel. Figure Q4: A process instrumentation diagram for a flash drum