Membrane-based reservoir dryer

A device for preventing ingression of contaminants and moisture and for removing moisture from a fluid comprising:

• a fluid, reservoir for supporting a fluid therein;
• a fluid reservoir opening for allowing an exchanging of gas between an interior of the fluid reservoir and the ambient surrounding;
• and
• a membrane-based reservoir dryer located in fluid communication with the fluid reservoir and distal to the fluid reservoir opening, the membrane-based reservoir dryer comprising a source of compressed gas, a filter and a coalescer for removing particulates and aerosol contaminants from the compressed gas, and a membrane dryer for drying the compressed gas to increase the capacity of the compressed gas for absorbing moisture from the fluid in the reservoir, and a metering device for controlling a desired volume of dry gas flowing into the fluid reservoir.

A method of preventing ingression of contaminants and moisture and removing moisture from a fluid reservoir comprising the steps of:

• directing a volume of compressed gas from a source of compressed gas through a filter and coalescer to remove particulates and aerosol contaminants from the compressed gas;
• moving the compressed gas through a membrane dryer to dry and increase the capacity of the compressed gas for absorbing moisture;
• injecting a metered amount of the dry gas into a fluid reservoir;
• allowing the dry gas to flow through a headspace of the fluid reservoir to remove moisture from the reservoir headspace and from the fluid in the fluid reservoir;
• and maintaining a slight positive pressure relative to an ambient pressure of the environment surrounding the fluid reservoir to prevent contaminants and ambient moisture from entering the reservoir headspace and from the fluid reservoir through a reservoir breather.