When the compressed air quality requires a pressure dew point value of ≤ 3 °C, the single use of the suction dryer can meet the compressed air quality requirements (pressure dew point depth), but because the suction dryer must consume electricity and gas to achieve, from the compression Air energy saving requirements are another pain point.

From the perspective of the process of compressed air purification, whether it is a cold dryer or a suction dryer, the water content of the air source at the beginning of the treatment is the same, that is, the compressed air whose intake air is saturated with water vapor at a certain pressure and inlet temperature . That is to say, if the suction dryer is used alone, 92.27% of the water removal workload is the same as that of the cold dryer when the pressure dew point is ≥3 °C, but it needs to consume much more electricity or product gas than the cold dryer. This is just like the "roughing and finishing" of the modern industrial processing method mentioned above, and the lady did the work of the maid, thus failing to save energy and increase efficiency.

Therefore, there is a combined dryer configuration on the market: cold dryer + suction dryer. The purpose is to use the cold dryer to dry rough processing (remove 92.27% of the water vapor, save energy), and then use the suction dryer for deep drying (ie finishing) to meet customer requirements. The author highly recommends the design and working concept of the combined dryer. The ingenious part is that the water vapor in the compressed air is removed by modern industrial processing methods: that is, the compressed air with saturated water content from the air compressor is directly dried to the pressure dew point temperature (-20℃, -40°C, -70°C) is decomposed into first rough processing (the compressed air with saturated water content from the air compressor will remove most of the water vapor by the cold dryer with less energy consumption, and the pressure dew point will reach 3°C) and then refined Processing (the suction dryer can use the compressed air with a pressure dew point temperature of 3°C from the cold dryer and then deeply dry it to meet the rated pressure dew point requirements) two processes are completed. In this way, it can not only meet the customer's requirements for the quality of compressed air, but also greatly reduce the power consumption and gas consumption of the suction dryer, and at the same time, it can prolong the replacement cycle of the adsorbent. Regardless of market breadth or depth, it is the most perfect combination of compressed air drying methods (combining refrigeration dryer and suction dryer technology) and can cover full dew point and full flow according to the production method of conventional dryers, which is very worthy of promotion.

The refrigerated dryer can not meet the original dew point requirements, and the suction dryer can make up for it. Therefore, it can be seen that the recommendation of a simple cold dryer + suction dryer in series has no adsorption theory support, no quality requirements, and no correct market guidance. Originally an energy-saving and high-efficiency combined compressed air dryer product failed to bring out the effect of the perfect combination of quality and energy-saving. High-quality customers who pay attention to energy saving (especially energy contract management or gas sales) need a combined compressed air dryer that is not a simple cold dryer + suction dryer in series