Distillation Column Packing

1. Raschig Rings

●For random packing in a column having a diameter approximately ten times larger than that of a Raschig ring, a required quantity of rings is calculated by :
n=Quantity of rings in 1 m3

D=Diameter of Raschig ring

C=0.77 (Constant for random packing)

For packing Raschig rings, Lessing rings and other annular products in order, the constant C=1.0.

Materials

Stainless steel, iron, aluminum, copper

H.Feat 1.62 1.37 1.19 1.09 0.97 0.90 0.78
Pressure mmHg 20 30 40 50 60 70 90

Characteristics

(Metallic Raschig Rings)

[1] High mechanical strength
[2] Light weight
[3] Uniformly layered with less probability of breakage
[4] High corrosion resistance
[5] Easy handling
[6] Applicable to columns of relatively large diameters

Diameter mm×Height mm×Wall Thickness mm Mesh(pcs/m3)
5φ×5H×0.4t 7,200,000 pcs
10φ×10H×0.3t 770,000 pcs
12φ×12H×0.3t 446,000 pcs
15φ×15H×0.5t 230,000 pcs
20φ×20H×0.6t 110,000 pcs
25φ×25H×0.5t 50,000 pcs
35φ×35H0.5t 17,000 pcs
40φ×40H×0.5t 12,000 pcs
50φ×50H×2.0t 6,160 pcs

2. Pall Rings

Materials


SUS304、316、316L

● A Pall ring has the same diameter and height, but is different from a Raschig ring in that several portions of the side wall are cut and bent inward so that a gas and a liquid can more efficiently come into contact with each other, achieving a lower pressure loss and a lower HETP than those of a Raschig ring. Pall rings are available in diameters of 12 mm (1/2 inch) or more.

Diameter mm×Height mm×Wall Thickness mm Qty/m3 Surface Area Void Ratio Density
12.7φ × 12.7H × 0.4t 410,000 430m2/m3 91.9% 640kg/m3
15.8φ × 15.8H × 0.4t 230,000 370m2/m3 92.9% 560kg/m3
25.4φ × 25.4H × 0.6t 51,000 210m2/m3 93.9% 480kg/m3
38.1φ × 38.1H × 0.8t 15,200 140m2/m3 94.6% 430kg/m3
50.8φ × 50.8H × 0.8t 6,500 110m2/m3 95.8% 330kg/m3

3. McMahon Packing

Materials

SUS304、316、316L

Characteristics

[1] Applicable to columns of relatively large diameters
[2] High void ratio and low pressure drop
[3] High throughput capacity
[4] Easy packing
[5] Low cost
[6] Applicable both to laboratory and industrial uses

Size Mesh Surface Area Void Ratio Density HETP
6mm(1/4") #42×100 1,590m2/m3 96.7% 380kg/m3 5cm
10mm(3/8") #38×80 1,405m2/m3 94.6% 420kg/m3 10~15cm
#38×60 1,137m2/m3 95.6% 340kg/m3
#36×60 1,185m2/m3 94.3% 450kg/m3
15mm(1/2") #36×60 922m2/m3 95.5% 450kg/m3 10~20cm
#36×50 843m2/m3 95.9% 320kg/m3
20mm(3/4") #34×40 693m2/m3 95.9% 320kg/m3 20~25cm
#32×35 556m2/m3 96.2% 300kg/m3
25mm(1") #34×40 392m2/m3 97.7% 180kg/m3 25~30cm
#30×30 327m2/m3 97.4% 202kg/m3

4. Dixon Packing

Materials

SUS304、316、316L

Characteristics

[1] Very low HETP
[2] Low pressure drop
[3] Specifically advantageous for vacuum distillation
[4] Easily replaceable

● A flat section of thin wire mesh is formed into a cylindrical shape with one end curved in an in ward S shape to intersect the inner space, so that Dixon packing is also known as S-shaped partition packing.
By preflooding several times, a higher efficiency is achieved

Size Mesh Surface Area Void Ratio Density HETP
3.0mm(1/8in) #42×100 3,009m2/m3 92.4% 600g/l 1.5~2cm
6.0mm(1/4in) #38×60 996m2/m3 96.2% 350g/l 2.5~3cm
10mm(3/8in) #36×50 580m2/m3 96.5% 280g/l  
15mm(5/8in) #36×50 400m2/m3 97.6% 190g/l  
20mm(3/4in) #34×40 240m2/m3 98.1% 150g/l  
25mm(1in) #34×40 210m2/m3 98.4% 130g/l