Can I lower the dew point by increasing the amount of desiccant?

As long as the desiccant is sufficiently regenerated, the longer water vapor is in contact with the desiccant, the lower the outlet moisture content will be, resulting in lower dew points. Increasing the amount of desiccant used in a heatless regenerative dehumidifying equipment will extend the time the water vapor is in contact with the desiccant and deliver low dew points.

Dew point in heated regenerative dehumidifying equipment is affected by not only the amount of desiccant but also adsorption performance. Adsorption performance is the degree of the desiccant's affinity for water, which depends largely on the temperature of the air stream and regeneration conditions regardless of the type of desiccant used.

Vapor pressure of outlet gas =                                  Vapor pressure of regeneration gas
Saturated vapor pressure at outlet temperature × Saturated vapor pressure at regeneration temperature

The above equation suggests that the same dew point will be achieved for any type of desiccant as long as it is regenerated under the same conditions. However, as you can see from the equation, you can lower the dew point effectively by increasing the regeneration temperature. This means that desiccants that have high heat resistance are ideal for producing ultra-dry compressed gases.

Environment and Energy Conservation