Performance analysis of a new kind of heat pump-driven outdoor air processor using solid desiccant

A new type of outdoor air dehumidification processor using solid desiccant is proposed, in which a heat pump and square desiccant plates are combined. Each desiccant plate consists of an air channel with a honeycomb structure that is coated with desiccant material. The square desiccant plates change positions between the processed air duct for dehumidification and the regenerated air duct for regeneration. The cooling capacity of the heat pump is utilized to cool the processed air, and the exhaust heat of the heat pump is used to provide regenerative heat to the desiccant. Several stages can be combined together to gain higher efficiency. The proposed desiccant dehumidifier can achieve a low humidity ratio of the supplied air and provides low-temperature regeneration. A mathematical model is established to predict the performance of this desiccant processor, and the model shows good agreement with the experimental results. The factors that influence the performance of the processor are then analyzed in order to maximize performance. The simulation results show that the proposed desiccant processor provides regeneration at a low temperature (40–50 °C), and the COP can surpass 4.0 at different processed air inlet states.

► A new dehumidifier with a multi-stage desiccant plate and heat pump is proposed.
► The proposed desiccant bed can be regenerated at a low regeneration temperature.
► A theoretical model is established and then validated by experimental results.
► The parameters influencing the performance of the proposed dehumidifier are analyzed.
► The COP of the proposed dehumidifier is greater than 4 under the designed parameters.