An insulation retaining assembly for a high temperature rotary pre-heater having a cold-end rotor and a hot-end rotor includes a plurality of elongate retainer elements. Each of the retainer elements has a root end adapted to be held in fixed relationship to the cold-end rotor and a distal end proximate to the hot-end rotor. Portions of each of the plurality of retainer elements are adapted for circumferential movement.

A fresh air conditioning system includes a first cooling device having a first cooling end and a first heating end; a dehumidifying rotary defining a first section and a second section. An airflow switching device directs a fresh airflow toward the first cooling end or the first heating end, and then flows to the first section. A return airflow passes through a first heat exchanger, and conducts heat exchange with the other end of the first cooling device, and then flows to the second section. Or switching opposite ends of the first cooling device to selectively cool or heat, the fresh airflow conducts heat exchange with one end of the first cooling device, and then flows to the first section. The return airflow conducts heat exchange with the other end of the cooling device and then flows to the second section.

A dehumidification system includes a first dehumidification unit having an outdoor air cooling heat exchanger, a second dehumidification unit using two adsorption heat exchangers such that an air passage is switched, and a third dehumidification unit having an adsorption rotor. Low-temperature low-humidity air cooled and dehumidified in the second dehumidification unit is supplied to the third dehumidification unit to reduce energy for recovery of the third dehumidification unit and to realize energy conservation in the dehumidification system and reduction in cost of the dehumidification system.