Page 433 - Air pollution and greenhouse gases from basic concepts to engineering applications for air emission control

13.4 Separation of Nanoaerosol from the Air 413

properties of a glass fiber filter for NaCl nanoparticles 1–100 nm when filter fiber
diameter d f ¼ 5 lm.
Solution
For salt particles and glass fiber filter

H p ¼ 7 10 20 J

H f ¼ 8:5 10 20 J

m 2
11
K p ¼ 0:75 10
N
m 2
11
K f ¼ 0:443 10
N
Then the Hamaker constant
p
1=2 ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
20 20
H ¼ H p H f ¼ 7 8:5 10 J ¼ 7:71 10 J
And the specific adhesion energy is

7:71 10 20 J
A H 2
Dc ¼ ¼ ¼ 0:0128 J m
9 2
12pZ e 2 12p 0:4 10 Þ m 2
ð
The composite Young’s modulus of bodies with the mechanical constants of K p
and K f

4 1 4 1

Y ¼ ¼ 11 11
3p K p þ K f 3p 0:75 10 þ 0:443 10
11
¼ 3:51 10 ðPaÞ
The characteristic radius of two bodies is

1
1 1 1

R ¼ þ
2 d p d f
The impact contact area is determined by

1=3

R

a ¼ ð 2DcpR Þ
Y
Then the adhesion energy is calculated using