Chart 2 shows the same rink condition of 60°F @ 40% RH. The total moisture removal of a desiccant unit rated at 10,000 SCFM is shown at 152.66 lbs/hr. this is a continuous per-hour capacity. The desiccant removes water in the vapor phase; no defrost is required. The unit is sized for 10,000 SCFM and will remove approximately three times the water vapor. Desiccant dehumidifiers are more effective and efficient at removing the water vapor at these low humidity levels.
The energy required to reactivate the desiccant load on the system is approximately 425,000 BTU/h. This energy input can be provided as natural gas, propane, electricity or a combination of those and
can incorporate waste heat. Energy recovery is available to reduce this energy requirement by an additional 20 to 30%.
To get an equal amount of dehumidification capacity, you need approximately three times the air flow through the glycol refrigeration system to handle a similar internal humidity load.*
To get a proper comparison for a refrigeration system to remove the same amount of water vapor from the air, we need to compare the energy required to remove 54.41 lbs/hr.
*Actual comparison based on water removal.