During the use of the air compressor, if the machine stops after failure, the crew must check or repair the air compressor on the premise of venting the compressed air. And to vent the compressed air, you need a post-processing equipment - cold dryer or suction dryer. Their complete names are air dryers and adsorption dryers, which are indispensable post-processing equipment for air compressors. So, what is the difference between a cold dryer and a suction dryer? What are the advantages and disadvantages of both? Let's take a look together.
1. What is the difference between a air dryer and a adsorption dryer?
① Working principle
The air dryer is based on the principle of freezing and dehumidification. The saturated compressed air from the upstream is cooled to a certain dew point temperature through heat exchange with the refrigerant, and a large amount of liquid water is condensed at the same time, and then separated by the gas-liquid separator. In addition, to achieve the effect of water removal and drying; the desiccant dryer is based on the principle of pressure swing adsorption, so that the saturated compressed air from the upstream is in contact with the desiccant under a certain pressure, and most of the moisture is absorbed in the desiccant. The dried air enters the downstream work to achieve deep drying.
② Water removal effect
The air dryer is limited by its own principle. If the temperature is too low, the machine will cause ice blockage, so the dew point temperature of the machine is usually kept at 2~10°C; Deep drying, the outlet dew point temperature can reach below -20°C.
③Energy loss
The air dryer achieves the purpose of cooling through refrigerant compression, so it needs to be adapted to a higher power supply; the adsorption dryer only needs to control the valve through the electric control box, and the power supply power is lower than that of the air dryer, and the power loss is also less.
④ Air volume loss
The air dryer removes water by changing the temperature, and the moisture generated during operation is discharged through the automatic drain, so there is no loss of air volume; during the operation of the drying machine, the desiccant placed in the machine needs to be regenerated after it absorbs water and is saturated. About 12-15% of the regenerative gas loss.
⑤Energy loss
The air dryer has three major systems: refrigerant, air, and electrical. The system components are relatively complex, and the probability of failure is greater; the adsorption dryer may fail only when the valve moves frequently. Therefore, under normal circumstances, the failure rate of the air dryer is higher than that of the adsorption dryer.
2.What are their advantages and disadvantages?
What are the advantages and disadvantages of air dryers?
Advantage：
①No compressed air consumption
Most users do not have very high requirements on the dew point of compressed air. Compared with the adsorption dryer, the use of the air dryer saves energy
②Daily maintenance is relatively simple
No wear of valve parts, just clean the automatic drain filter on time
③Low running noise
In the air-compressed room, the running noise of the air dryer is generally not heard
④Less solid impurity content in the gas discharged from the air dryer
In the air-compressed room, the running noise of the air dryer is generally not heard.
Disadvantages:
The effective air supply volume of the air dryer can reach 100%, but due to the restriction of the working principle, the dew point of the air supply can only reach about 3°C; every time the intake air temperature increases by 5°C, the refrigeration efficiency will drop by 30%. The air dew point will also increase significantly, which is greatly affected by the ambient temperature.
What are the advantages and disadvantages of adsorption dryers?
Advantage
①Compressed air dew point can reach -70℃
② Not affected by ambient temperature
③ Filtration effect and filter impurities
Disadvantages:
①With compressed air consumption, it is easier to consume energy than air dryers
②It is necessary to add and replace the adsorbent regularly; the valve parts are worn out and require daily maintenance
③Absorptive dryers have the noise of depressurization of the adsorption tower, and the operating noise is about 65 decibels
The above is the difference between the air dryer and the adsorption dryer and their respective advantages and disadvantages. Users can weigh the pros and cons according to the quality of the compressed gas and the cost of use, and equip a dryer corresponding to the air compressor.
Post time: Jun-21-2023
