Re: Blower For Filling Rice
Dear Jet Tech,
When I was working as a project engineer for a very big grain stevedoring company in Rotterdam, it was already experienced, that rice is too friable for pneumatic (vacuum) conveying.
Even at the lowest possible airflows, whereby the pneumatic conveying almost stopped, it was not possible to convey rice without acceptable breakage.
The solution then (1980-1985) was: grab-unloading. (Dust was acceptable)
Also some seeds (used for bird seed) were damaged unacceptably.
succes ■
Teus
Re: Blower For Filling Rice
Dear Teus Tuinenburg,
Thankyou for your response. We did explore this option of grab loadinh and unloading. Though this process works well while unloading from the ship hold, It is not possible to apply the same to containerised trucks which have the loading and unloading thru the back and not at the top. Do you have any solutions for these kind of containerised trucks.
Some one suggested to us to first fill the container with high pressure air and then load the grains, the air pressure slows down the falling grains and the grain gently glides down. It was tried and tested earlier and was successful. When we tried it was not very good. The breakage was down but still not within acceptable.range. Maybe the air pressure or point of air discharge was not correct.
A second method someone suggested was using a hinged barrier or flap in front of the blower mouth made of some soft material which will act as a padding. We have not tried this as we do not know which material to use.
Do you have any clue as to the above 2 methods. Or any other.
Regards ■
Re: Blower For Filling Rice
I assume you are talking about standard back filling ISO containers?
If you are, don't try to pressurise them, they have 0 gauge design pressure and in practice they will only take 10 or 20 mbar before the flat side walls and roof are not so flat any more.
A few other options are:
1) The Redler thrower (http://www.redler.com/products/standard/bulkthrower.htm)
This may cause a little less product damage than a pneumatiuc system but whether any improvement is enough would I guess require some testing.
2) Gravity Filling
In some parts of the world, a common method of filling these containers is to lift them on some sort of frame, the frame then tips and the product falls in under gravity.
3) what about using a cantilevered belt conveyor, en-masse conveyor or other mechanical device which you can retract as the container fills? ■
Re: Blower For Filling Rice
RPD,
Thankyou for your response.
The pressure required is not more that 2 or 3 bars, its just that we are not able to do it properly.
I shall contact redler for their thrower.
tilting is not possible because these are mounted containerised trucks. If nothing works out then we will use detached containers and tilt them.
Thank you. Shall get in touch with you if I need any further assistance.
Regards ■
Blower for filling rice
We want to fill rice in bulk quantities in trucks and shiphold using pneumatic blowers. However there is a problem in doing so. When we try to fill rice by these blowers the rice grains break. this leads to loss in quality as rice grains quality are measured in the grain length. The lesser breakage the better quality.
Usually 3-4%breakage is acceptable but while filling via blower we find almost 20%breakage.
The reason for breakage could be colliding amongst them selves and also colliding against truck walls.
Can any one develop a suitable equipment for us.
Regards
Jet Tech. ■