Technical Sheet of HOC Type Absorption Air Dryer
| Equipment name | zero air consumption heat of compression desiccant dryer |
| Inlet air capacity | Std.210.0 Nm3 / min | 12600 Nm3 / Hr |
| Dryer working principle | TSA temperature swing adsorption + split flow cycle regeneration |
| Working period (single tower) | ≈240 min | Max.300 min |
| Regeneration air loss | 0% |
| Inlet air pressure | Std.7 bar |Min. 6 bar Max.10 bar |
| Pressure loss at full load | ≤7% of inlet pressure |
| Inlet air oil requirements | Oil-free compressed air |
| Inlet air temperature | Std.140℃ | Min.120℃, Max.180℃ |
| Outlet pressure dew point | ≤-40℃ |
| Absorption air dryer power | 50.2 KW |
| Blower power | 7.5KW |
| Electric heater power | 50KW (heating by 40% flow) |
| Heating temperature | UCL：150℃，LCL：120℃ |
| Cooling water flow | ≤116T/Hr |
| Cooling water pressure | Std.3 bar Min 2 bar Max:6 bar |
| Cooling water temperature | temperature rise | Std.20℃ Min 2℃ Max:27℃ | 5℃ |
| Absorption dryer weight | 12000 Kg |
| HOC air dryer size | 2950 H×5000 L×3200W |
Why Choose Our Zero Air Loss HOC Type Absorption Air Dryer
(1) Energy Efficient
Among all the adsorption air dryers, this one is the most energy-efficient. Compared to a normal HOC dryer, it adds an auxiliary high-efficiency cooler. So, it achieves complete zero air consumption. Compared with a heatless air dryer, it can save energy by about 80%.
Now, let’s take an example. And compare the energy consumption of different desiccant dryers. For instance, a 175m³/min oilless centrifugal air compressor exists. And the power is 925KW. Assume that the centrifugal air compressor works 365 days a year. At the same time, it runs continuously each day. In addition, the electricity fee is CNY1.05/kWh. The water fee is CNY0.22/ton.
Specific energy consumption of each absorption dryer:
| No. | Air Compressor Air Dryer | Calculation of energy consumption for each absorption air dryer |
Annual operation fees | Compared to heatless dryer, how much energy it can save? |
| 1 | Heatless desiccant air dryer | The ratio of regeneration air consumption is about 15%. (925KW×15%)×24h×365d×CNY1.05 =CNY1276222/year |
CNY1276222 | High energy consumption |
| 2 | Heat regenerative adsorption dryer | Single tower cycle is 4h. Additionally, regeneration air volume is 8%. And heater power 70KW. Heating time 1.5h. Cold purge time 2.0h. (925KW×8%×3.5h+70KW×1.5h×75%)× 6 times×365d×CNY1.05=CNY776656/year. |
CNY776656 | 39.10% |
| 3 | Zero air loss blower purge desiccant dryer system |
Absorption cycle is 4h. Zero gas consumption. Heating time 1.5 h. Heating power 110 KW. In addition, cold purge time 2.0 h. Blower power 18 KW. And blower start time is 3.5 h. (110KW×1.5h×75%+18KW×3.5h)×6 times×365d× CNY1.05=CNY429431/year |
CNY429431 | 66.30% |
| 4 | Micro air consumption HOC dryer | The adsorption cycle is 4h. And 5% of cold purge air consumption. Cold purge time 1.5h. Cooling water consumption: 90t/h. Power consumption: (925KW × 5% × 1.5h) × 6 times × 365d × CNY1.05= CNY159527/year; Water consumption: 90t/h×24h×365 days× CNY0.22 =CNY173448 /year; So the total energy consumption of this absorption dryer=CNY159527/year + CNY173448 /year=CNY332975/year |
CNY332975 | 73.90% |
| 5 | Zero air loss HOC dryer | The adsorption period of absorption air dryer is 4h. Cooling water consumption: 135t/h. Water consumption: 135t/h×24h×365 days×CNY0.22 =CNY260172 /year |
CNY260172 | 79.60% |
(2) Stable Dew Point
Our HOC dryer is with an EBZ200-2 multi-core drive intelligent control system. Besides, it adopts PLC for intelligent control. It automatically adjusts for optimum operating efficiency. And it ensures thorough regeneration. Therefore, the dew point is much more stable.
In addition, there are air distribution devices at the bottom of the dryer. This increases the contact time with the adsorbent. Make sure the dew point temperature meets the requirements. Our zero air loss absorption dryer can reach -20 and -40℃.
(3) Use High-performance Metal Seated Pneumatic Butterfly Valve
The temperature conditions of the HOC dryer vary greatly. Ordinary valve gaskets are prone to aging and deformation. So, it will cause the valve not to seal tightly. Finally, it will affect the performance of the absorption air dryer. In particular, it affects the dew point of the desiccant dryer.
To eliminate these problems, we use high-performance metal seat valves. They can withstand high temperatures. Besides, it is a German original brand.
(4) High Quality And Sufficient Desiccant Beads
Firstly, our HOC dryer has ample desiccant beads. 25~28kg adsorbent per cubic air. Therefore, it can maintain a high drying effect.
Secondly, choose a well-known brand of adsorption desiccant. The particle size is 3~5mm. Good water resistance. Moreover, we use the best filling method. It can prevent desiccant from sinking. So it has a longer service life.
Specific Workflow of “heat of compression” Dryer
(1) Adsorption Drying Process of HOC dryer
This process is the same as other absorption air dryers. Adsorbents hold water vapor. This process continues until another tower finishes the regeneration process.
(2) Regeneration Process of Desiccant Air Dryer
The regeneration process consists of 3 steps: twin towers co-current → {hot purge → thermal delay → cold purge} → twin towers co-current
① Two Towers Co-current
Sometimes, the absorption air dryer shuts down abnormally. This can avoid affecting the outlet temperature.
② Thermal Purge Process
Take tower A adsorption as an example. The high-temperature air enters the B tower from the V2 valve. Then, it starts thermal purging from top to bottom. Afterward, the main cooler will cool them to the adsorption temperature. Finally, enter Tower A.
③ Cold Purge Process
The thermal purge process ends. At this time, desiccant beads are in a dry state. So, it must cool to be ready for the next adsorption. Then, the cold purge process starts.
The high-temperature air is cooled to about 40℃ by the main cooler. Then, it performs a cold purge to tower B through the V4 valve. Next, flow through the auxiliary cooler to cool to the adsorption temperature. Finally, enter the A tower from V8 and V5.
FAQs
The use of compression heat dryers is conditional.
It is generally only suitable for centrifuges and oil-free screws. Compressed air inlet temperature should be above 110°C. Besides, the dew point requirements are not strict. For example, -20℃, or -40℃. At this time, the energy saving of the HOC absorption dryer is beyond doubt. It can achieve zero air consumption.
But sometimes customer requirements are very strict. For example, they require a dew point lower than -40℃. And the inlet temperature is not always guaranteed to reach 110°C. Then, the energy saving of the HOC absorption air dryer will be greatly reduced. At this time, we should choose a micro air consumption dryer. It’s better than a zero air loss HOC adsorption dryer.
Yes. For the HOC absorption air dryer, we must confirm the inlet air temperature. It usually cannot be lower than 110°C. Sometimes, the intake air temperature is lower than 110°C. Besides, users have strict requirements on dew point. Then, the desiccant dryer must add auxiliary heating.
For a single tower, it’s about 240 minutes. Namely, 4 hours. Many people believe that long-term operation is good. I think it shows the energy saving and performance of the adsorption dryer. But this does not apply to zero air-loss desiccant air dryers.
For other dryers, the regeneration process releases moisture-laden air into the atmosphere. However, the HOC absorption dryer is different. It will carry some moisture from the previous cycle to the next one. The cycle adsorption capacity of an HOC dryer is much larger than that of other dryers. Therefore, if we need the same dew point, we can increase the filling amount of the adsorbent. However, shortening the adsorption cycle is the best way. So, a short cycle time is good for zero air loss absorption air dryer.
