Pre-selection for positive-displacement process gas compressors

Gas Guides

The machine is chosen by the gas before it is chosen by the pressure. One page per gas: the properties that drive the choice, the families that serve it, and the boundaries.

H2

The smallest molecule in the plant sets the hardest rules.

CO2

Well behaved when dry, carbonic acid when wet — and above 7.38 MPa it stops being a gas at all.

Cl2

Dry chlorine and wet chlorine are two different jobs — the moisture content in ppm is the governing parameter.

CH4 mix

The baseline fuel-gas duty — and the one where the gas analysis matters more than the name.

NH3

Toxic, mildly flammable, and it eats copper — every component in the gas path counts.

O2

Oxygen service is a cleaning discipline before it is a machine discipline.

N2

The baseline process gas — inert, cheap and forgiving. Selection here is driven by pressure and flow, not chemistry.

VCM

One gas with a hard temperature ceiling of its own: 100 °C, because polymerisation starts there.

CH4/CO2 mix

Raw biogas carries H₂S and water together — that combination decides the machine before pressure does.

He

The leak champion — its molecules escape through clearances that hold nitrogen.