Freeze dryer operating principle and operation guide

Freeze-drying (hereinafter referred to as lyophilization) is a method in which a water-containing substance is first frozen into a solid state, and then the moisture therein is sublimated from a solid state to a gaseous state to remove the water and preserve the substance. The freeze dryer mainly consists of a drying box, a condenser, a refrigerating unit, a vacuum pump, and a heating/cooling device. It is a machine composed of a refrigeration system, a vacuum system, a heating system, and an electrical instrument control system.

Works <br> <br> air in the freeze dryer is determined by the amount of water vapor in the compressed air temperature: in case of maintaining a substantially constant air pressure, compressed air may be reduced to reduce the temperature of the compressed air The water vapor content, and the excess water vapor will condense into a liquid. Freeze dryers use this principle to use refrigeration technology to dry compressed air. Therefore, the dryer has a refrigeration system.

Freezer Dryer Operation Guide

Cautions when the freeze dryer is turned on:

1, open the main power switch on the left side of the chassis, the pressure is displayed as atmospheric pressure 110pk;

2. Press and hold the key on the control panel for more than three seconds. The temperature is displayed as the actual temperature of the cold trap.

3, start the refrigerator, pre-cooled more than 30 minutes;

4, put the sample into the sample holder, cover with a cover glass, and start the vacuum pump;

5. After the pressure is stable, record the temperature and pressure values.

Precautions when the freeze dryer stops:

1. Record the temperature and pressure value before shutdown;

2. Press and hold the inflation valve on the control panel and immediately turn off the vacuum pump.

3. When the atmospheric pressure is at atmospheric pressure, open the plexiglass hood and take out the sample;

4, close the refrigerator, press and hold the key to open the total more than three seconds, and finally turn off the main power switch;

5. After the ice in the cold trap is completely turned into water, open the water outlet valve on the left side of the chassis to drain water, clean the inner wall of the cold trap with a dry cloth, and put on a large piece of filter paper to prevent dust.