Dust Control In Transfer Stations
The best way to control dust in the transfer of bulk solids from one belt to the next is to maintain a constant material velocity and minimize rotation of the material charge. Sounds simple.
How do you know that you have accomplished this feat before building the chute? Of course experience leads to improvement. Can you guarantee success? To do so, you would have to compute the mathematical phenomenon of particles and gas interactions.
Conveyor Dynamics, Inc. (CDI) does have such tools and can identify the terminal velocity of all particles, by size, that will lift against gravity when the terminal velocity is exceeded. This is done using coupled solid partical and gas modeling of the flow field. Discrete Element Modeling (DEM) with coupled gas dynamics is now capable of analyzing the ore transfer and identifying the gas velocity map that will cause fugitive dust generation. The model can also assist in minimizing the particle and gas dynamic interaction and, as suggested above, minimize flow field disturbance once the ore has left the discharge pulley.
Want to know more?
Visit our web site: www.conveyor-dynamics.com
We will be posting in the near future some of the solid-gas interaction modeling. The site does now demonstrate the principles.
Lawrence Nordell
Conveyor Dynamics, Inc. ■
Modification Of Belt Conveyor Hood
We used the well-known "Clevelad Cascade
effect", successfully proved itself in handreds
of loading chutes.
The main rule of the effect is:
keep the fall speed of the material stream
about 2m/s and the dust problem will be
solved!
So, we calculated and welded side plates
in the existing hood and... reduced the
dusting drastically!
In very short existing chutes such solution
will be unpractical.
Michael Rivkin ■
Re: Modification Of Belt Conveyor Hood
Micahel,
Thought I would give you another try.
Give me the geometry details of the hood transfer, and the other pertinent information and I can tell you what can be done in the limited space you have.
Lawrence Nordell ■
Re: Modification Of Belt Conveyor Hood
Dear Mr. Rivkin,
Please clarify, whether you are referring to dust generation in discharge spout surrounding the discharge pulley or dust generation in very large height dropping chute, wherein you are suggesting to incorporate impact shelves (speed breakers).
Basically, the dust generation will be minimum, if the material stream remains compact with minimum turbulence, and velocity is restricted to reasonable limit.
Again, what is the name of the material and its size distribution?
Situation will be different, if it is completely powdery material or it is routine material mixed with lumps.
Regards,
Ishwar G Mulani.
Author of Book : Engineering Science and Application Design for Belt Conveyor.
Email : parimul@pn2.vsnl.net.in
Tel.: 0091 (0)20 5882916 ■
Modification of Belt Conveyor Hood
Most of the dry bulk materials, dropping into
head drum hoods, create a lot of airborne
dust.
The special dust suppression facilities are
usually installed to reduce the dust
pollusion.
Sometimes more simple and inexpensive
measures can be taken to reduce the
dusting.
We welded in one of our hoods a number
of deflection plates in "zig-zag" order,
to reduce the velocity of the falling
material stream.
The result was the significant reducing of the dust
generation . ■