First, the principle of system configuration of refrigeration air dryer
The refrigerated compressed air dryer reduces the temperature by cooling, so that the water vapor in the compressed air condenses into droplets, thereby achieving the purpose of reducing the moisture content. The condensed droplets exit the dryer through an automatic drainage system.
Compressed air with saturated water vapor enters the precooler of the dryer. In the precooler, the incoming hot air is cooled and cooled first, reducing the load on the system (this process is precooling). The pre-cooled air enters the evaporator. Here, the heat released from the air is absorbed by the refrigerant and cooled to a preset temperature (2 to 7°C). After the air is cooled, it forms droplets of water vapor, which is separated from the air by a steam separator, and discharged from the air through an automatic drain. After leaving the steam separator, cold air enters the shell of the precooler. The inlet hot air undergoes heat exchange and leaves the dryer after being heated to approximately 10°C from the inlet air. This reheating prevents secondary condensation of the outer outlet air line and the downstream line, and also increases the energy of the air, improving the utility. In addition, after the compressed air passes through the dryer, the solid dust of 3 μm or more has been filtered out, and the quality of the air source is required to be clean and dry.
Second, the working principle of micro heat regeneration adsorption air dryer
The micro-thermal regeneration adsorption dryer adopts the alternate operation of the twin towers. The compressed air enters the tower of the dryer A through the valve 1A (1B closed), and the gas is dehydrated and dried under the unique adsorption effect of the adsorbent. The finished gas passes through the valve 5A (5B). Closed) to the point of use, while about 5% of the dry gas source is heated by the heater and then passed through the valve 4B (4A closed) into the tower B. After heating for a certain period of time, the adsorbent is regenerated and stopped. After heating, it enters the cold blowing stage to cool down the adsorbent bed of the desiccator tower B (to prepare for the next cycle), and then discharges it into the atmosphere through the silencer, closes the valve 2B before switching in the second half of the cycle, and opens the valve 1B to make the two tower bodies. After the pressure is equalized, the switching is completed (guaranteing the stable use of the gas pressure and avoiding the impact shock of the dryer). At the same time, the work is started in the second half of the cycle (operation of the dryer B tower and regeneration of the dryer A tower), and the flow is similar to the first half cycle.
Third, the combined air dryer works:
The combination dryer is reasonable to combine the freeze dryer and the adsorption dryer together. The air treated by the dryer does not pass through the pre-cooler, and directly enters the adsorption dryer after draining from the separator of the dryer. At this time, the temperature of the drying air is about 2°C-5°C, and the dew point is about 5°C. At this time, the adsorption dryer continues to perform deep adsorption, and the lower the temperature of the adsorption dryer is, the better the dew point is. Therefore, the combined dryer can achieve a more stable pressure dew point. Before entering the adsorption dryer, a part of the water has been removed by the cold dryer, which reduces the workload of the adsorption dryer. Therefore, the adsorption dryer can be switched for a longer time, thereby reducing the air consumption.