Re: Dilute Phase Conveying / Pet Flakes
Dear mohamedgomaa,
Your shared information is not complete to verify your calculation.
Missing info is:
- Flake dimensions (probably crushed PET bottles) :
-Length
-Width
-Thickness
-Ambient conditions (T, p, RH, Altitude above sea level)
-PET Density
The conveying distance must be split in:
-Horizontal length
-Vertical length
-Number of bends
-Feeding device?
-Why pressure conveying?
-Have you considered a vacuum system?
-How do you know that the cyclone must be big with a large outlet?
i need solid calculate so i can design my cyclone
-What do you mean by this?
-Have you considered a filter receiver combination? A cyclone is not a 100% separator.
You state:
-1200 m3/hr. = 0.33333 m3/sec = 1.15 * 0.33333 = 0.38 kg/sec airflow
-Capacity is 6 tons/hr. = 6/3.6 = 1.667 kg/sec material flow
-The Solid Loading Ratio (S/A) is then 1.667/0.38 = 4.39
-Your calculation gives 3.5
-Particle velocity = 22 m/sec.
-The calculated air velocity is: 0.3333/0.0081 = 41 m/sec
-Did you estimate the particle velocity approx. times the air velocity?
-I am not convinced that the PET flakes are moving that slow, compared to the air velocity.
-Or the flake resistance factor must be very high. ■
Teus
Re: Dilute Phase Conveying / Pet Flakes
for
Flake dimensions (probably crushed PET bottles) :
-Length 10 - 15 mm
-Thickness 1 mm
-PET Density : 250 dry
- Horizontal length15
- Vertical length 10
- Number of bends 3
- Feeding device? I am receiving the PET from screw conveyer
- Why pressure conveying? i am replacing the current system which uses pressure conveying
- How do you know that the cyclone must be big with a large outlet?, as i know the density is very low and this material is not free flowing si its need large cyclone, Please correct me if I am wrong
- Have you considered a filter receiver combination? A cyclone is not a 100% separator/ for the pressure conveying the dust out from cyclone will be accepted
ur calculation is right
I used Penucalc software for my calculations its almost the same as urs
the flasks velocity at the pick up point 29 m2/s ■
Re: Dilute Phase Conveying / Pet Flakes
Dear mohamedgomaa,
i am replacing the current system which uses pressure conveying
Why calculating an existing system that is replaced?
PET material density is approx. 1380 kg/m3
PET flake bulk density is 250 kg/m3
Check the input of your calculation software. ■
Teus
Re: Dilute Phase Conveying / Pet Flakes
i wanted to learned more so that i recalculated the system, for the pet density that the exact values i had added
i only have a problem in the cyclone i can't design it, i have the design guide but for powders but i dont think it will work with the flakes ■
Re: Dilute Phase Conveying / Pet Flakes
Dear mohamedgomaa,
i wanted to learned more so that i recalculated the system, for the pet density that the exact values i had added
Have you checked, whether the calculations matched the actual operation performance and parameters?
They must be equal.
i only have a problem in the cyclone i can't design it, i have the design guide but for powders but i dont think it will work with the flakes
Try to reverse engineer the existing cyclone with the design guide and check whether the result matches the existing cyclone
Shepherd and Lapple (1939-1940) developed a series of cyclones, whereby the dimensions are related to the cyclone body diameter.
Apply their calculation algorithm. ■
Teus
Re: Dilute Phase Conveying / Pet Flakes
Dear mohamedgomaa,
Based on the limited information, I did a "quick calculation":
Calculation result.
6 tons/hr. at 305 mbar
Including 250 mm diameter cyclone high efficiency 1 (height 1025 mm)
Air velocity = 35 – 38 m/sec
Pet flake velocity:
10 m/sec – 27 m/sec horizontal
23 m/sec vertical
Maximum capacity:
17 tph at 650 mbar
The flakes are considered as "tumbling disks" whereby the drag coefficient is changing based on the projected area. ■
Teus
Dilute Phase Conveying / PET Flakes
I am working on a design for conveying PET Flakes with a pressure conveying conveying .
Capacity : 6 Ton /hr with 30 m distance B.d : 250 kg/m3
i have done my calculation and got that
flow : 1200 m3/hr
d.p 350 mbar
pipe size 4 ''
S/A : 3.5
particle velocity +22
I have questions a bout the cyclone i know it has to be big with a large out let but i need solid calculate so i can design my cyclone can anyone help in this ? ■