Question

I want to know how to determine the pressure of the High pressure gas(motive gas) which used to compress the flare gas to discharged at intermediate pressure!!

Answer 1

Determining of high pressure such as in case of motive gases a device called bulk modulus cell is used.This consists of a hollow cylindrical steel probe closed at the inner end with a projecting stem on the outer end.When this is exposed to a process pressure ,the probe is compressed and the probe tip is moved to the right by the isentropic contraction and then the stem moves further outward.This stem motion is then converted into pressure reading.This is how the flare gas is discharged to intermediate pressure.