Twin Tower Regenerative Adsorption Dryer

1. Adsorption stage
Intake: Wet compressed air is fed through the intake valve into one of the adsorption towers, assumed to be Tower A. Air enters from the lower pipe at the bottom of the tower and flows from the bottom up.
Adsorption of water: Tower A is filled with strong hydrophilic adsorbents, such as activated alumina, molecular sieve, etc. When the wet air passes through the adsorbent bed, the water in it is adsorbed by the adsorbent, so as to realize the drying of the air.
Dry air output: The dry air absorbed by the adsorbent is discharged from the upper pipe at the top of Tower A to provide dry compressed air for subsequent gas equipment or processes.

2. Regeneration stage
Regas introduction: While tower A is adsorbed, Tower B enters the regeneration stage. A small amount of dry air (usually about 10%) is pumped from the main circuit as re-gas and enters Tower B through the re-gas regulating valve of the upper piping system. Then the gas is purged from the top down to the adsorbent in tower B.
Water desorption and discharge: Since the regas is dry air that has been decompressed, during the purging process, the water in the adsorbent is desorbed and discharged into the atmosphere along with the regas through the B2 valve and muffler of the lower pipe system. In some micro-thermal regeneration adsorption dryers, the gas will first be heated by a heating device to improve the regeneration effect, so that the moisture in the adsorbent is more thoroughly desorbed.

3. Pressure equalization stage
Pressure balance preparation: After the end of the regeneration stage, the B2 valve is closed, and Tower B begins to enter the pressure equalization stage.
Pressure rise: The pressure in tower B gradually increases until it is consistent with the working pressure of tower A during the adsorption stage. The pressure equalization process is usually faster, but the stability of the pressure balance needs to be ensured to avoid pressure fluctuations during subsequent switching.

4. Switch phases
Valve action: After the pressure equalization is completed, the B1 valve of the lower piping is opened, the A1 valve is closed, and the A2 valve is opened.
Working state transition: Through the switch of the valve, the working state of the two adsorption towers A and B is transformed. B tower enters the adsorption stage and begins to absorb water in the wet air; Tower A enters the decompression and regeneration stage, ready for the next regeneration treatment, and so the cycle is repeated to achieve a continuous supply of dry air.

1. Chemical industry: In the process of petroleum refining and chemical product production, many chemical reactions and processes require a dry gas environment. For example, the production of ethylene, propylene and other olefins, dry compressed air is used to drive pneumatic equipment, instrument control, etc., to prevent water from affecting the catalyst, to ensure the smooth progress of the reaction and product quality; In the natural gas purification process, it is used to remove water in the natural gas to prevent the formation of hydrates during transportation and storage, blocking pipelines and equipment.

2. Pharmaceutical industry: Pharmaceutical production has strict requirements for environmental humidity. In the process of drug crushing, mixing, granulation, drying, etc., dry compressed air is needed to prevent the drug from being spoiled by moisture and ensure the stability and quality of the drug. In the air purification system of the aseptic workshop, the twin tower regenerative adsorption dryer ensures that the air sent into the workshop is dry and clean, meeting the GMP requirements of pharmaceutical production.

3. Food and beverage industry: In the process of food processing, such as bread baking, meat processing, beverage filling, etc., dry compressed air is used to drive pneumatic tools, equipment and packaging machinery, etc., to avoid moisture resulting in equipment rust, product deterioration or microbial breeding; In the food preservation and packaging links, dry air can be used for air conditioning packaging to extend the shelf life of food.

4. Electronics industry: The production and manufacture of electronic components is extremely sensitive to air humidity. In semiconductor chip manufacturing, circuit board assembly and other processes, it is necessary to use dry compressed air with high purity and low dew point to prevent moisture condensation on the surface of components, resulting in short circuit, corrosion and other problems, affecting product performance and reliability; In the LCD production process, dry air is used for cleaning, blow-drying and other processes to ensure product quality.

5. Automobile manufacturing industry: In the automobile painting workshop, dry compressed air is used to drive the spray gun and transport the paint to ensure the quality of the coating and prevent bubbles, flow and other defects; In the automotive engine assembly process, dry air is used for cleaning and drying parts, as well as driving pneumatic tools to ensure assembly quality and normal operation of equipment.

6. Machining industry: In the machining process, such as CNC machining centers, pneumatic fixtures, pneumatic tools, etc., need to use compressed air. The twin tower regenerative adsorption dryer can provide dry air source, prevent the corrosion of pneumatic components due to moisture, extend the service life of the equipment, and improve the processing accuracy and efficiency.

7. Air separation industry: In the process of producing high-purity oxygen, nitrogen, argon and other gases, it is necessary to remove the water in the air to ensure the normal operation of the gas separation equipment and the purity of the product gas.

8. Printing industry: Many pneumatic parts of the printing press, such as paper dispensing mouthpieces, paper delivery mouthpieces, air valves, etc., need dry compressed air to drive, to ensure the accuracy and stability of the printing process, and to prevent printing equipment failure or printing quality problems caused by moisture in the compressed air.

1. What are the advantages of double tower regeneration adsorption dryer compared with single tower adsorption dryer?
Dual tower regeneration adsorption dryer can continuously supply dry air, one tower adsorption when the other tower regeneration, switching work to ensure the continuity and stability of the air source. However, the single-tower adsorption dryer needs to stop the gas supply when the adsorbent is regenerated, and can not achieve continuous dry gas supply.

2. How long does the adsorbent of the twin tower regeneration adsorption dryer generally need to be replaced?
The replacement cycle of the adsorbent depends on a number of factors, such as the humidity of the intake, the oil content, the working pressure, the temperature, and the use time. Generally speaking, if the intake conditions meet the requirements of the equipment, the service life of activated alumina and other adsorbents under normal circumstances may be about 3 to 5 years, and the molecular sieve may be about 5 to 8 years, but if the intake quality is poor or the working condition is harsh, it may need to be replaced in a shorter time.

3. What preparations need to be made before starting the twin tower regenerative adsorption dryer?
It is necessary to check whether all components of the equipment are normal, including whether the valves and pipelines are tightly connected without leakage. Check the status of the adsorbent to see if it needs to be supplemented or replaced; Ensure that the control system is normal, set the working parameters such as switching time, etc. Check whether the intake air temperature and pressure are within the allowable range of the equipment; It is also necessary to ensure that the power supply and air supply are normal.

4. What is the reason for the large pressure fluctuation during the operation of the equipment?
It may be a valve failure, such as the valve is not tightly closed or opened in time, resulting in gas leakage or poor airflow; It may also be that the adsorbent in the adsorption tower appears caking, crushing, etc., affecting the gas flow and pressure stability; Or the control system has a problem, the switching time is not accurate; In addition, the unstable intake pressure may also lead to fluctuations in the operating pressure of the equipment.