Guideline for selection of frozen compressed air dryer
To select a frozen dryzer, it is required to consider the actual flow, pressure of the compressed air as well as ambient temperature and the pressure dew point required. The cold dryer processing volume is Qs=Qa×C1×C2, where the Qa is the actual flow of the compressed air.
For example:
The inlet air pressure of the dry compressor is 0.7Mpa, the inlet air temperature is 40°C, ambient temperature is 40°C, the actual flow of air compressor Qa is 0Nm3/min, the pressure dew point required is + 20°C, then the processing volume of the cold dryer is Qs=Qa×C1×C2, and according to Tables 1 and 2, C1=0.80, C2=1.22, so Qs=9.76, and it is most appropriate to select the specification KSAD-10SF.
Dew point conversion table
Table 1 Pressure and temperature modification coefficient of compressed air (C1)
Inlet temperature (°C) |
Air inlet pressure (Mpa) |
||||||
0.4 |
0.5 |
0.6 |
0.7 |
0.8 |
0.9 |
1.0 |
|
25 |
0.49 |
0.43 |
0.40 |
0.37 |
0.35 |
0.33 |
0.32 |
30 |
0.57 |
0.52 |
0.46 |
0.42 |
0.40 |
0.37 |
0.36 |
35 |
0.84 |
0.77 |
0.71 |
0.65 |
0.62 |
0.59 |
0.57 |
40 |
0.99 |
0.91 |
0.85 |
0.80 |
0.77 |
0.74 |
0.72 |
45 |
1.20 |
1.11 |
1.05 |
1.00 |
0.97 |
0.94 |
0.92 |
50 |
1.37 |
1.30 |
1.24 |
1.18 |
1.14 |
1.10 |
1.07 |
Table 2 ambient temperature and pressure dew point correction factor (C2)
Ambient temperature (°C) |
Pressure dew point |
|
|
2°C |
10°C |
25 |
0.65 |
0.34 |
30 |
0.78 |
0.46 |
35 |
1.00 |
0.66 |
40 |
1.22 |
0.86 |
Relation between atmospheric dew point and moisture
Dew point (°C) |
Moisture (g/m) |
Dew point (°C) |
Moisture (g/m) |
Dew point (°C) |
Moisture (g/m) |
Dew point (°C) |
Moisture (g/m) |
14 |
12.07 |
-5 |
3.407 |
-24 |
0.7678 |
|
|
13 |
11.35 |
-6 |
3.169 |
-25 |
0.7074 |
-43 |
0.1298 |
12 |
10.66 |
-7 |
2.946 |
-26 |
0.6463 |
-44 |
0.1172 |
11 |
10.01 |
-8 |
2.737 |
-27 |
0.5922 |
-45 |
0.1055 |
10 |
9.309 |
-9 |
2.541 |
-28 |
0.5422 |
-46 |
0.9501 |
9 |
8.819 |
-10 |
2.358 |
-29 |
0.4960 |
-47 |
0.08544 |
8 |
8.270 |
-11 |
2.186 |
-30 |
0.4534 |
-48 |
0.07675 |
7 |
7.750 |
-12 |
2.206 |
-31 |
0.4141 |
-49 |
0.06886 |
6 |
7.260 |
-13 |
1.876 |
-32 |
0.3779 |
-50 |
0.06171 |
5 |
6.797 |
-14 |
1.736 |
-33 |
0.3445 |
-51.1 |
0.054 |
4 |
6.360 |
-15 |
1.605 |
-34 |
0.3138 |
-53.9 |
0.040 |
3 |
5.947 |
-16 |
1.483 |
-35 |
0.2856 |
-56.7 |
0.029 |
2 |
5.559 |
-17 |
1.369 |
-36 |
0.2597 |
-59.4 |
0.021 |
1 |
5.192 |
-18 |
1.261 |
-37 |
0.2359 |
-62.2 |
0.014 |
0 |
4.847 |
-19 |
1.165 |
-38 |
0.2141 |
-65.0 |
0.011 |
-1 |
4.523 |
-20 |
1.074 |
-39 |
0.1940 |
-67.8 |
0.008 |
-2 |
4.217 |
-21 |
0.9884 |
-40 |
0.1757 |
-70.6 |
0.005 |
-3 |
3.930 |
-22 |
0.9093 |
-41 |
0.1590 |
-73.3 |
0.003 |
-4 |
3.660 |
-23 |
0.8359 |
-42 |
0.1438 |
|
Frozen Compressed Air Dryer
1. Heat exchanger 2. Evaporator 3. Gas-liquid separator 4. Automatic drainer 5. Cold-medium compressor 6. Vaporizer 7. Thermal expansion valve 8. Sight glass 9. Dry filter 10. Condenser (water cooling) 11. Hot gas by-pass valve 12. Oil component 13. Condenser (air cooling) 14. Refrigerator 15. Pre-cooler |