Dew Point

The temperatures below which either hydrocarbons (hydrocarbon dew point) or water (water dew point) will start to condense out of a given gas stream. Condensation reduces the accuracy of metering and creates the nuisance of liquid slugs in pipelines, which will need to be cleared out periodically by passing a Pig though the pipeline. In addition, water may react with carbon dioxide or hydrogen sulphide in the gas stream to form acids, and with methane itself, under appropriate conditions, to form Hydrates. Therefore, at the Treatment stage, water is normally removed from the gas stream to reduce the Dew Point to somewhere around -10°C at standard pipeline pressures.