1. Direct cooling method
Since the water content of natural gas decreases with the decrease of temperature, direct cooling to reduce the temperature of natural gas can reduce the water content of natural gas. However, the efficiency of this method is too low and it is difficult to meet the requirements of gas dew point, so it can only be used as an auxiliary means.
2. Pressurized cooling method
Since the water content of natural gas decreases with the increase of pressure, increasing the pressure of natural gas can reduce the water content of natural gas. The combination of pressurization and cooling can improve the dehydration efficiency of natural gas. However, the pressurization and cooling in natural gas processing are not the same as dehydration, but the process needs.
3. Expansion refrigeration cooling method
When the pressure of the well gas is high, the natural gas can be cooled and dehydrated by the low temperature obtained by the high-pressure expansion of the gas. When the temperature of the expanded gas is low, the method of injecting ethylene glycol or diethylene glycol inhibitor is started to inhibit the formation of hydrate.
The expansion refrigeration method can not only remove more water from the high-pressure fluid at the wellhead, but also separate more hydrocarbons than the normal temperature separation method. Therefore, some high-pressure condensate gas wells are often used.
