Belt inclination for iron ore pellets

Posted in: , on 30. May. 2008 - 09:55

Dear Experts,

What is the maximum angle of inclination of belt used successfully, for iron ore pellets for a DRI Plant [Midrex / HYL]?

We at Essar [surat, India] normally use 8 deg and incase of less space, upto 10 deg. Our experience is after 11 deg, the problem of pellet rolling back starts. 15 deg, is not even thought for pellets.

We are told by one of the suppliers that 13-16 deg inclination is being used very regularly without any problems & 4M plant in monterra, Mexico, is using 15 deg inclination. Also, we are told a DRI plant in Malysia is using conveyors with 15 deg inclination, for pellets.

Iron ore Pellets details are as under -

Size : 20 mm sperical shape

Bulk density : 2.2 - 2.4 T/M3

Angle of repose : 34 deg

Angle of surcharge : For calculation, this is taken as 10

Belt conveyor capacity is 500 - 700 TPH

Elevation of discharge end is approx 85 m.

Elevation of feed end is 2 m.

We are finalizing layout for a new plant and space requirements change a lot with different angle of inclination.

Would appreciate opinions of experts.

Regards

Ravindra Lele

Essar Engineering Services Limited

Hazira, Surat, India

Re: Belt Inclination For Iron Ore Pellets

Erstellt am 3. Jun. 2008 - 01:59

Hi Ravindra

8 (even 11) degrees is OK but the trouble is to handle the low capacities during starting and stopping the feed. The pellets roll on the flat middle section of the belt.

For this reason, I use 2 or 4 roll idlers, to give me a vee in the middle, to concentrate the pellets.

Cheers

LSL Tekpro

Graham Spriggs

Re: Belt Inclination For Iron Ore Pellets

Erstellt am 4. Jun. 2008 - 05:48

Dear Sir,

You are right. Normally, srtart, stop and when feed is less, we have problems of rollback.

Any opinion on 15 deg angle for normal troughed belt?

Regards

Ravindra Lele

Re: Belt Inclination For Iron Ore Pellets

Erstellt am 4. Jun. 2008 - 08:43

Ravindra..

For normal troughed belt, on normal materials like coal or rock with a reasonable size distribution, 15 degrees is fine. I often use 17 degrees.

However, if there are large lumps present, these can roll back and be dangerous, so I limit inclines to 13 degrees in such cases, and often use 4 rolls.

For round pellets though, 8 min to11 max degrees as discussed.

Cheers

LSL Tekpro

Graham Spriggs
Axel Witt
(not verified)

Re: Belt Inclination For Iron Ore Pellets

Erstellt am 4. Jun. 2008 - 03:09

Dear Sir,

from my experience in the past it is beneficial to limit the inclination in the loading area to max. 10°. And depending on speed you can slightly increase the inclination by a few deg. as soon as the material is being carried safe on the belt after several meters (>10m). In the discharge area I would recommend to lower the inclination in order to prevent pellets jumping around.

Maybe there are some experts that use the discrete element method to give more information and theoretical background on this issue.

Regards and GLUECKAUF from Germany!