The oil content of the air in the intake tower should be controlled below 0.01PPM. In view of the fact that some oil-free air compressors cannot be truly oil-free, it is necessary to install an oil-removing filter at the air inlet of the dryer in order to prevent the accumulation of trace oil in the adsorption bed (such accumulation is very fast). The adsorption dryer shall be used under the condition of rated temperature and pressure. When the inlet air temperature is higher than or the inlet air pressure is lower than the rated value, the capacity shall be modified. When the adsorption dryer and piston air compressor are used together, the stabilized air storage tank should be set in front to eliminate the high-speed impact of pulsating air flow on the adsorbent; When there is a freeze dryer in front, the connection between the adsorption dryer and the freeze dryer should be installed separately as far as possible as long as the site permits, in order to reduce the air pressure drop, improve the ventilation conditions of the freeze dryer and facilitate daily maintenance and repair; When the gas supply is sufficient, the regenerative dryer without heat can be listed as the first choice, and its dew point is lower and more stable.