Perumal,
BDV is a safety arrangement to remove inventory out of system in case of emergency and minimise chances/impact of surface rupture of pipe/equipment.
emergency scenario for which BDV to be provided is system specific . typical example is Fire scenario.
As per API guideline, system pressure need to be reduced to 100 psig or 50% of design pressure, whichever is lower within 15 minutes of time.
also you may encounter low temperature issue while depressuring, hence an RO is installed downstream of BDV to limit flow such that low temperature will not cause metal embrittlement. or else you need to choose costly material which will withstand low temperature. Also it helps to limit noise and vibration problem.
For compression system, a BDV is generally provided if I) settleout pressure is exceeding design pressure ii) for Fire scenario
Since your operating parameters are quiet low in general terms, it seems that BDV is provided to remove inventory considering fire scenario.
I hope this helps to analyse you further 'System specific scenario'.
However please note that BDV Provision criteria suggested by you (i.e. 17 barg pressure or 4m3 of system volume ) is unheard of and seems came from some wrong information.
....
Amit