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Desiccating agent consumption calculation

Calculation method by JIS Z 0301

The desiccating agent, please find the consumption by the following expressions depending on a use and the situation. 
 
(1)
 
W: Consumption (g) of the desiccating agent
R: Of JIS Z 0208 [vapor permeance test method (cup method) of the moisture-proof wrapping]
      Vapor permeance (g/m2, 24h) of the moisture-proof wrapping by condition B
A: Surface area (m2) of the moisture-proof packing
t: Packing period Sunday (= 24h) (1)
h1: Mean humidity (%) of the fresh air during a packing period
h2: Mean humidity (%) (2) in the packing during a packing period
K1: Moisture-proof wrapping coefficient (3) to be decided by kind and average temperature θ ℃ during a packing period
C1: Moisture absorption rate (%) of the desiccating agent at the time of the beginning to use
C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the relative humidity of the maximum permitted by the packing inside
K2: Wrapping coefficient (4) to be decided by a moisture absorption rate with the absorbency in the packing
D: Mass (g) of the wrapping with the absorbency in the packing
 
Note (1)
 
When a change of temperature, the humidity during a packing period is big, you divide a packing period properly and calculate the desiccating agent consumption during each period and may add this.
   (2) For kisanchi, I take the middle value with the humidity of the maximum permitted within humidity and packing in the early packing.
   (3) I calculate the value of K1 by the next expression.
 
Pθ: I can put it in mean temperature θ ℃ during a packing period
        Moisture-permeable rate (g, cm/cm2, s, kPa) of the moisture-proof wrapping
P40: Moisture-permeable rate (g, cm/cm2, s, kPa) of the moisture-proof wrapping in 40 degrees Celsius
pθ: I divide saturated steam in θ ℃ (kPa)
p40: I divide saturated steam in 40 degrees Celsius (kPa)
 
I show a value of K1 in various temperature of the film for the reference ... a lot of packing to the reference list.
Film
40 degrees Celsius
35 degrees Celsius
30 degrees Celsius
25 degrees Celsius
20 degrees Celsius
15 degrees Celsius
10 degrees Celsius
5 degrees Celsius
Polyester
11.1 x
10-3
7.3 x
10-3
4.9 x
10-3
3.1 x
10-3
2.0 x
10-3
1.27 x
10-3
0.81 x
10-3
0.48 x
10-3
Low density
Polyethylene
11.1 x
10-3
7.0 x
10-3
4.5 x
10-3
2.8 x
10-3
1.8 x
10-3
1.05 x
10-3
0.63 x
10-3
0.36 x
10-3
High density
Polyethylene
11.1 x
10-3
6.9 x
10-3
4.4 x
10-3
2.7 x
10-3
1.7 x
10-3
1.0 x
10-3
0.59 x
10-3
0.33 x
10-3
Polypropylene
11.1 x
10-3
6.9 x
10-3
4.3 x
10-3
2.5 x
10-3
1.6 x
10-3
0.92 x
10-3
0.53 x
10-3
0.29 x
10-3
Polychlorination
Vinylidene
11.1 x
10-3
6.5 x
10-3
3.9 x
10-3
2.2 x
10-3
1.3 x
10-3
0.74 x
10-3
0.40 x
10-3
0.21 x
10-3
Note (4)
 
 
 
 
 
 
I calculate K2 by the next expression.
C1: Moisture absorption rate (%) of the desiccating agent at the time of the packing start
C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the humidity of the maximum permitted within packing
C3: Equilibrium moisture absorption rate (%) of the wrapping with the absorbency in the humidity of the maximum permitted within packing
C4: Moisture absorption rate (%) of the wrapping with the absorbency when I put it in the packing
 
(2)
I calculate R = 0, the consumption of the desiccating agent at the age of D = 0 by the next expression.
V: The space capacity (m3) in the packing container except the capacity of the packing contents
H: Absolute humidity (g/m3) in the temperature-humidity at the time of the packing
C1: Moisture absorption rate (%) of the desiccating agent at the time of the packing start
C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the humidity of the maximum permitted within packing
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