How to choose the cold dryer vs suction dryer
Conclusion: Look at your requirements for the degree of gas dryness. The requirement is not high, the requirement is high, the requirement is high, the choice is suction dryer, the budget is enough for both.
First, the essential difference. The idea of the cold dryer is to freeze the gas, and the water vapor becomes water droplets when it is cold, just like the water from the wall of the ice beverage cup. It can dry the gas to a dew point of about 2 to 10 degrees Celsius, which is sufficient for daily use. The idea of the suction dryer is to let the gas pass through a material that can absorb water. The water is caught by the material and the gas is dry. It can depress the dew point to minus 20 degrees Celsius or even lower, and the degree of drying is much deeper.
Besides, how to match the oil-free air compressor with water lubrication. Water lubricated oil-free air compressor works with water to participate in the compression, the gas discharged without oil, but with a lot of water vapor. So when you choose a dryer, you don't have to consider degreasing, you just need to concentrate on solving the water problem. The cold dryer has no problem dealing with a large amount of water vapor, and because there is no oil interference, the heat exchange efficiency of the cold dryer is more stable and is not easy to be blocked by oil. If your gas usage scenario is just pneumatic tools, spraying, and ordinary manufacturing, the cold dryer is enough, with less money, simple maintenance, no gas consumption, and low noise.
However, if you are an industry that is extremely sensitive to water vapor such as electronics, medicine and food, the drying depth of the cold dryer is not enough, and water may still be condensed in the pipeline. At this time, the suction dryer must be added. The suction dryer is not affected by the ambient temperature, regardless of the summer and winter effects are stable, and can dry the gas to a very thorough degree.
Two together is the safest solution. The installation sequence is that the air compressor comes out and passes through the cold dryer first, removes most of the water, and then enters the suction dryer for deep drying. In this way, the cold dryer helps to reduce the burden on the suction dryer, the adsorbent of the suction dryer has a longer service life, and the overall cost is more economical.
An account is to be calculated on the operating cost. The cold dryer consumes electricity but does not consume air. The suction dryer does not consume much electricity but consumes about 10% to 1.5% of compressed air during regeneration. The failure rate of the cold dryer is higher because it has several sets of refrigerant and electrical systems and many parts. The structure of the suction dryer is simple, mainly because the valve occasionally has problems, and the whole is more durable. Maintain the cold dryer and clean the filter screen regularly. The suction dryer needs to change the adsorbent every few years.
In a word, it is enough for ordinary-purpose cold dryers, and high-demand suction dryers. The optimal solution is that the cold dryers and suction dryers are connected in series, and the water-lubricated oil-free air compressor is very suitable for water treatment.