Combined Compressed Air Dryer Introduction
Combined dryer is a new energy-saving air-treatment equipment. It mainly includes three parts. That is,refrigerated dryer, precision filters and compressed air dryer desiccant.
It takes fully the advantages of refrigerant dryer and desiccant air dryer for compressor. Therefore, we can get a lower dew point. Moreover, the energy consumption is very low. So this combination compressed air dryer system has excellent performance.
Technical Specifications of Combination Compressed Air Dryer Desiccant
|Suitable Medium||Compressed air/nitrogen|
|Cooling Mode of Refrigerant Dryer||Air-cooled|
|Regeneration Type of Desiccant||Heatless regeneration & micro-heated regeneration|
|Air Dryer for Compressor|
|Average Consumption of Regeneration Air||4~6 % for heatless dryer, 3~5% for micro-heated desiccant dryer|
|Inlet Air Pressure||Std.7 bar | Min 5 bar Max:10 bar (high pressure customizable)|
|Air Inlet Temperature||Std.50 ℃ | Max:80℃|
|Ambient Temperature||Std.32 ℃ |Min 2℃ Max:45℃|
|Pressure Loss||≤0.61 bar|
|Available Pressure Dew Point||(-20℃, -40℃, -70℃)|
|Outlet Air Oil Content||≤0.01 PPM|
|Desiccant Beads||High efficiency activated alumina + molecular sieve (3~5mm)|
|Compressed Air Filter||Pre-filter, dust-removal filter,oil-removal filter, activated carbon filter|
|Working Principle||Pre-cooling + low temperature condensation + efficient water|
|separation + heat recovery + precision oil-removal + deep adsorption|
Advantages of Combination Compressed Air Dryer
① Energy Saving
There is no air loss for refrigerated dryer. However, the air consumption of heatless dryer is generally 13%. A micro-heated dryer also has about 6% air loss.
But combination dryer has lower air consumption. For example, the heatless combination type is 4~6%. And micro-heated combination type is 3~5%. So it is more energy efficient.
② More Stable And Lower Dew Point
Combination dryer is ideal for obtaining low dew points. Air compressor produces high-temperature, high-humidity compressed air. Firstly, a refrigerant dryer cools them to about 2~10°C.
At this time, it has discharge most gaseous water. What’s left is compressed air with very low moisture content. So, the working load of compressed air dryer desiccant is very low. Thus we can achieve -70℃ dew point easily. Also, the dew point is more stable.
③ Reduce The Floor Space
Refrigeration dryer and desiccant air dryer for compressor are on the same base. So, it reduces the floor space.
④ Easy to Install
Filters and piping are already installed on compressed air dryer system. Therefore, it reduces the installation process of the user.
Why Choose Our Combination Air Dryer For Compressor
- Our combined dryers serve customers together with famous air compressor brands. For example, our 6.5m³/min combination dryer works with a Kobelco oil-free air compressor, as shown in the picture above. Moreover, our other compressed air dryer desiccant often works with Atlas Copco, Ingersoll Rand, Sullair, Kaeser, Hitachi, etc.
- Refrigerated dryer uses famous brand refrigerant compressors. For instance, we use Hanbell, Danfoss, Copeland, and Panasonic brands. Therefore, the cooling capacity is super strong. Besides, there is built-in safety protection. So it has stable performance and high efficiency.
- Refrigerant dryer is with precooler and heat exchanger. Therefore, it can reduce the load of refrigerant compressors. So, a compressed air dryer system can adapt to severe working conditions. The maximum inlet temperature can withstand 80 ℃.
- Our desiccant air dryer for compressor adopts high-performance adsorbent. The pneumatic control valve is also an imported brand. So it has reliable performance and a long lifetime. Moreover, an airflow diffuser is at the bottom of the adsorption dryer. Therefore, it ensures the long-time contact between compressed air and desiccant beads. Then, dew point can be guaranteed.
- In addition, we use high-quality filters. The filter element adopts USA HV filter paper. The housing is cast aluminum. The maximum pressure can reach 16 bar. The temperature of the filter is 80°C. The lifetime of the filter element is generally 8000 hours. Shell life can be up to 10 years.
It is a combination of refrigeration dryer + compressed air dryer desiccant. Preliminary drying in a refrigerated dryer. It removes a lot of moisture. Thereby, the workload of the adsorption dryer is greatly reduced. In addition, only a small amount of water remains. A regenerative desiccant air dryer dries them. As a result, we get low dew point dry air.
The adsorption dryer has a lighter workload. Therefore, the required regeneration air will be greatly reduced. It makes compressed air dryer systems more energy efficient.
Specific Process Flow of Combination Air Dryer:
Firstly, the compressed air enters the precooler. They exchange heat with dry compressed air from a desiccant dryer. So it will increase their temperature. At the same time, the temperature of the compressed air entering the evaporator is reduced. Finally, it removes some water. Also, cool them down to room temperature. The workload of the evaporator is also reduced.
Then, enter the evaporator for heat exchange. Cool the compressed air. So, it achieves a dew point temperature of around 5°C. At this time, it has completed preliminary dehumidification. Then, they enter the desiccant air dryer for the compressor.
The adsorption dryer adopts the PSA principle. It can get a lower dew point. Dry air comes out of the adsorption tower. Then, they return to the precooler in the refrigerant dryer. They will cool hot and humid air. Besides, they also will raise their own temperature. So, it is also beneficial to the regeneration of air.
How to Choose The Combined Compressed Air Dryer
(1) Confirm Basic Paramters
Firstly, inform the air capacity, inlet temperature, and pressure. So we know which model to choose. In particular, different inlet air pressures are also different. The freeze dryer can be 16 bar, 25 bar, 40 bar, 60 bar, or 100 bar. And compressed air dryer desiccant can also be 1.6MPa, 2.5MPa, 4.0MPa to 10.0MPa.
Therefore, our combination dryer can also do medium pressure and high pressure. We also need to tell the dew point. One of the advantages of a combination dryer is the low dew point. We can do it up to -70°C.
(2) Air-cooled or Water-cooled Refrigerant Dryer
The air-cooled refrigerated dryer is easily affected by ambient temperature. Especially in summer, the dryer is under heavy load. So it has an impact on dew point. Generally, it requires good ventilation.
There is no such problem for a water-cooled dryer. However, there needs to be a cooling water system. For example, it requires cooling pumps or towers. So, the initial investment is relatively large. But the working condition is more stable. If water resources are abundant, we can choose it.
(3) Confirm The Desiccant Air Dryer For Compressor
There are many types of compressed air dryer desiccant. Just their energy efficiency is different. For example, the regeneration air consumption of a heatless combination dryer is 4~6%. The air loss of micro-heated is 3~5%. So, if energy-saving requirements are not high, you can choose them.
However, sometimes customers are concerned about saving energy. At this time, we need to choose a zero air loss desiccant air dryer.
In addition, there is also a modular compressed air dryer system. Its biggest advantage is its small size. It is easy to transport.
(4) Combination Dryer Material
Sometimes customers require dryers of stainless steel. For example, the food and pharmaceutical industries require SS304.
We can customize a stainless steel refrigerated dryer. And also produces stainless steel compressed air dryer desiccant. In addition, filters and pipes can also be SS304.
In fact, the housing of our modular adsorption dryer is aluminum alloy. It’s also special for the pharmaceutical and food industries.
Combination Air Dryer User Manual
(1) Install The Refrigerant & Desiccant Air Dryer For Compressor
- The ambient temperature should generally not exceed 40 ℃.
- It needs good ventilation. But don’t install a compressed air dryer system outdoors.
- The installation environment should be dry. There should not be wet.
- In advance consider the convenience of maintenance. Besides, should maintain a horizontal position. So as not to affect the discharge of condensed water from the dryer.
- We should prevent the dryer from being vibrated by the piping system.
- Pipe diameter should not be smaller than the size of the compressed air dryer desiccant.
- The pipeline should not be too long. So as not to cause water accumulation and large pressure drop.
(2) Use Precautions
- You should install a power switch separately. Besides, the dryer’s working pressure must not exceed the rated value.
- Do not share a protective device. The voltage fluctuation range shall not exceed 10% of the rated voltage.
- The cables should not be too thin or too long. To avoid a voltage drop of desiccant air dryer for compressor.
- The casing of the compressed air dryer system should be grounded reliably.
- The power supply voltage is 380V/50HZ. (Other voltages can be customized).
- Also, ensure there is good ventilation.
- Check whether the inlet air temperature and pressure are normal.
- We must cut off the compressed air dryer desiccant before maintenance.
- Before maintenance or disassembly, pressure must be relieved first.
- Check whether the cooling water is normal.
- After running for 30 minutes, check whether the drainage system is normal.
(3) Compressed Air Dryer System Operation
Firstly, turn on the start button of the refrigerated air dryer. So it starts to work. And wait about 5 minutes. Then, let compressed air into the dryer system.
Wait for towers A and B to have the same pressure and stand still. Then, turn on the power supply of the desiccant air dryer for compressor. Press the “Start button”. So the dryer starts to work fully automatically.
② Shut Down
Firstly, close the air inlet valve of the dryer. Then press the “Stop Button” on the two dryers. So they will stop working. Then, cut off the power to the compressed air dryer system.
③ Dry The Adsorbent
Use the self-drying method. Close the dry air outlet valve. Then, remove the orifice plate from the regeneration air tube. Increase the amount of regeneration air.
The load of compressed air dryer desiccant is very low now. The bottom layer has very little moisture absorption. A larger amount of finished air is used for regeneration and drying. Its dryness is high.
After 24 hours of drying, wait to reach the required dew point. Then, install the orifice plate. Finally, the desiccant air dryer for compressor is in the normal adsorption state.
④ Filling And Replacement of Adsorbent
We have used desiccant beads for a while. Usually three years. If the dew point is too high, it is necessary to check the adsorbent. Remove some from the tower. Check to see if it is contaminated (yellow in color).
If it is, must replace the desiccant pellets. We can take them out from the discharge port. Or fill from the upper loading port.
⑤ Replacement of Filter Element
The normal service life of the filter element is generally 8000~9000 hours. If the use time is short, the dryer dew point is high. Indicates that the air contains too much oil. So, we should replace the filter element in time. At the same time, check whether the oil discharge of the air compressor is normal.
(4) Control Panel Description of Compressed Air Dryer System
① Refrigerant high-pressure meter: Show the condensing pressure of the dryer refrigerant.
② Refrigerant low-pressure gauge: indicates the evaporating pressure of refrigerant in the dryer evaporator.
③ A tower pressure gauge: indicates the air pressure of tower A of compressed air dryer desiccant.
④ Tower B pressure gauge: Show the air pressure of tower B of the desiccant air dryer for compressor.
⑤ Start button (blue color): Press this button to start the compressed air dryer system.
⑥ Stop button (red): press this button to stop the air compressor dryer.
⑦ Power indicator (red): The external power supply is normal if the light is on.
⑧ Running indicator light (green): The dryer runs normally when this light is on.
⑨ Abnormal indicator light (yellow): When this light is on, it indicates that compressor air dryer is faulty.
(5) Electrical And Automatic Control
The refrigerant dryer adopts a closed refrigeration cycle. It has a thermal expansion valve and a hot air bypass valve. The refrigerant expands directly. Finally, enter the evaporator. Sometimes, the production conditions and environment will change. This can cause changes in the evaporator heat load. At this time, both these two valves are automatically adjusted. Therefore, it can ensure a constant temperature for the dryer evaporator. So it prevents ice jams.
In addition, our compressed air dryer system is with safety protection devices. For example, it has refrigerant high and low-pressure controllers. It also has a current overload protector. In case of refrigerant leakage, it will cut off power automatically. Therefore, the compressor will be not damaged.
The compressed air dryer desiccant has a PC program controller. It can control the alternate adsorption and regeneration of the Twin Towers. Besides, it can display the working status in real-time. Moreover, it can control desiccant air dryer for compressors with time delay. Easy to use. And works reliably. The display is intuitive and clear.
(6) Combined Dryer Maintenance
① Maintenance of Sewage System
|Parts Name||Maintenance Content||Maintenance Purpose|
|Manual drain valve||Manually drain once a day||In order to avoid failure of the electronic|
|drain. At the same time, drain the oil and|
|water from the compressed air dryer system|
|Y type anti-blocking ball valve||Clean the inner filter once a week||In order to prevent blockage|
|Electronic timing automatic drain||Manually test the drainage once a day;||Drain the water from refrigerated dryer and|
|Clean the inner filter once a week;||compressed air dryer desiccant in time.|
|Float automatic drainer||Observe the drainage every day;||Same to above|
|Clean the inner filter once a week;|
|② Filtration system|
|Parts Name||Maintenance Content||Maintenance Purpose|
|Oil, dust and water removal filter||Must replace the filter element||Reduce pressure drop. Enhance the filtering|
|1~2 times a year||effect. Prevents aging glass fibers from|
|Regulator filter||Check pressure settings every 2 weeks||The set pressure of butterfly valve model|
|Condensate water filter||Clean the inner filter once a week||Strengthen the dredging of cooling water.|
|Improve refrigerant condensation effect.|
|Reduce compressor high pressure.|
② Refrigerated Air Dryer
|Parts Name||Maintenance Content||Maintenance Purpose|
|Water cooled condenser||Clean the condenser at least 2 times a year||Improve the condensation effect of|
|compressed air dryer system|
|Air cooled condenser||Purge condenser once a week||Strengthen the condensation effect|
|of the refrigerant|
|Refrigerant compressor||Check oil level, current, inlet temperature||——|
|Bypass valve||Adjust the opening according to low pressure||——|
|Expansion valve||Adjust the opening according to low pressure||——|
|Dry filter||Replace regularly. Replaced at the same time as||——|
|the replacement of refrigerant|
|Refrigerant high pressure gauge||Check the pressure range often||Normal value 1.2~2.0MPa|
|Refrigerant low pressure gauge||Check the pressure range often||Normal value 0.35~0.45MPa|
③ Desiccant Air Dryer For Compressor
|Parts Name||Maintenance Content||Maintenance Purpose|
|High quality desiccant beads||Generally, we replace desiccant beads
every 2 years. But it’s best to check the
|In order to ensure the water absorption
performance of the adsorbent
|Pneumatic valves||Observe the 4-valve action sequence.
Also check the valve for irrelevant problems.
|Ensure that the air intake and exhaust are normal.
At the same time eliminate air leakage.
|Muffler silencer of compressed
air dryer desiccant
|Observe the exhaust. Control the air consumption
of desiccant air dryer for compressor.
|When the AB tower during regeneration, if the pressure
cannot be reduced, need to replace it.
|Diffuser||Replace regularly. It is recommended to check the
diffuser when changing the desiccant beads.
Combined Compressed Air Dryer System Troubleshooting
(1) Poor water removal effect of refrigerant & desiccant air dryer for compressor
|Piping system error||Bypass valve not fully closed||Close the dryer bypass valve|
|Air not passing through compressed air||Tighten the bypass valve. Also open|
|dryer desiccant & refrigeration||the inlet & outlet valves|
|Dryer not level||put compressed air dryer system on level|
|Auto drain inclined||put it on level|
|Too much air flow||Heat load is too high||Re-design the air source|
|Abnormal drainage system||Bad drain||Clean or change it|
|Abnormal evaporator outlet||Dew point is too low or too high||Adjust the pressure switch|
|Ambient temperature is too high||Can still use the air compressor dryer|
|Inlet temperature is too high||Add a rear cooler|
|Refrigerant leakage, so poor cooling effect||Repair leaks, then add refrigerant|
|Adsorbent not working well||Desiccant beads failure||Replace adsorbent for desiccant air dryer for compressor|
(2) Pressure drop too high
|Compressed air piping||Pipe diameter is too small||Increase pipe size|
|The pipeline is too long and||Design piping system again|
|there are too many elbows|
|Filter blockage in line||Replace filter element|
|Too much air leaks at the pipe connection||Check elbow fittings|
|The dryer air capacity exceeds||Exceeds the rated flow of compressed air||Replacing a compressed air dryer|
|rated value||dryer desiccant & refrigerant. Pressure is||system with a larger capacity|
|Condensed water in the||Bad temperature switch||Renew, check circuit, correct switch|
(3) Controller and adsorption system problems
|Programmable controller||No current input||Check voltage on terminal block|
|indicator does not light up|
|The power switch fails||Replace the power switch|
|Controller internal fault||Fix it|
|High outlet dew point||Air capacity exceeds maximum||Change to compressed air dryer|
|desiccant with bigger model|
|The desiccant pallets have expired||Replace the adsorbent|
|The adsorbent is contaminated||Firstly, check the compressed air filters.|
|Then replace the desiccant beads|
|Intake pressure too low or intake air||Increase intake pressure or decrease|
|temperature too high||intake temperature|
|It doesn’t reach the working||Regeneration valve is not closed tightly||Overhaul the regeneration valve of|
|pressure when charging||desiccant air dryer for compressor|
|Too much dry compressed air||Reduce dry compressed air output|
|The pressure in the regeneration||Muffler blocked||Clean or replace|
|tower is greater than 0.02MPa|
|Regeneration valve is not fully open||Fix the regeneration valve|
|Poor check valve seal||Fix the check valve of compressed|
|air dryer system|