How to replace the Desiccant for Adsorption Air Dryer

Adsorption air dryer, also named desiccant air dryer, is a part of the screw air compressor system, it is normally used for those industries which required dew point below -20℃, such as pharmaceutical industry, food industry, electron industry, instruments, and etc. Adsorption air dryer for air compressor is widely used in compressed air system.

If the adsorption dryer is found to have poor effect during use, it is necessary to replace the desiccant.
After the dryer has been used for around 10000hrs (around one and a half years), it needs to be replaced. Adsorption air dryer to be filled with desiccant shall follow the principle of uniform, tight and no dead ends left. Uneven filling is easy to generate airflow tunnels in the adsorption tank to short-circuiting the compressed air and affecting the air dew point of adsorption air dryer. When filling the desiccant, we generally uses the method of vibration filling and layering and tamping, and the proper operation can basically meet the requirements. Remove the bad desiccant and leave the good desiccant to be filled in the bottom of the adsorption tank until the upper part of the cylinder is filled with the newly filled desiccant. Do not use sticks to prevent them from crushing, so as to ensure normal operation.

Steps for replacing desiccant in adsorption air dryers:

1. The adsorption dryer is equipped with filling and discharge ports on each drying tower, remove the two cover plates.
2. In order to help the desiccant flow out of the drying tower, a small rod can be inserted into the discharge port if necessary. Because the desiccant is packaged into the tower, it may affect the smooth flow out of the tower.
3. The coarse filter screen installed on the inlet and discharge pipe joints of the tower is removable on all models. It is recommended that these filters are also removed for cleaning when changing the desiccant. (The filter screen can be accessed after dismantling the upper and lower gas collecting pipes from the drying tower)
4. Reinstall the filter screen after cleaning, and then plug the outlet plug.
5. After removing all filler plugs, inject desiccant of appropriate grade and specification. The desiccant height level should meet the requirements of the desiccant filling table.
6. Once the two towers are filled, re-plug the filling port of each tower.
7. Any joints that are disturbed during the replacement of the desiccant should be tested for leaks, and then the dryer can be re-adjusted.