An LPG filling station might require a storage tank, pumping skid, interconnecting piping, metering station, protection systems, fire protection systems, loading station and bowser, civil works and structural works, etc.
An LPG filling station design require a piping engineer, a process engineer, a static equipment mechanical engineer, a rotating equipment engineer, civil and structural engineers, designers, etc. Which position might be suitable for you? Hope you're not going to say supervisor...
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gr2vessels