Screw Conveyors vs. Spring Conveyors

Hi Sandeep,

Is this for a batch process. The reason I'm asking, is that we used to charge solids into our batch reactors by vacuum. Pull a good vacuum on the vessel and attach a hose and charging lance with a valve. Stick the lance into the drum or bag containing the powder, open the valve on the lance to the vessel, and suck the powder in.

Make sure you use a steel lance and ground it or you will get zapped!

Keep in mind that you cannot do this with some solids; flammable solids/oxidizers-NO! hygroscopic solids - not a good idea!

As far as what type conveyor, it would probably depend on the consistency of the solid material.

Mike

You want to go with a direct drive screw conveyor.

Anything else will cause the powder to stir and fluff up and get all over everywhere.

A screw conveyor will just lift the powder directly through the tube without causing too much stiring action.

Several people here like the screw idea, but I'm not sure there's enough information to draw a conclusion. Powder composition, desired velocity or flow rate, safety concerns, geometry of the move and I'm sure a host of other concerns beyond my imagination need to be understood to make a reasonable decision.

check out using air/vacuum.

i recommend you forget screws and/or conveyors. i would be concerned with abrasion on the equipment by the powder transferred using screws/conveyors. i have personally operated lime transfer equipment for years using air pressure.

for your distance of ten to twelve feet, i would probably use a single pressurized "pot" as opposed to a long pipeline with multiple pressure induction points. what i mean by my comment follows: I have experience with two air pressure systems used to move powder products.

Number 1:

the first setup used high pressure discharged into a pressure vessel. we would release all psi from the system, open solenoid valves allowing product to flow into the vessel from a silo located above it, seal all inlet valves, pressurize the vessel, open solenoid valves on the discharge side of the vessel - whoosh goes the powder. make sure the pipeline and the receiver (tank, bin, whatever) can withstand the psi, force of the material, AND captures dust generated by this technique.

Number 2:

we modified the above setup to the following. the problems we faced with high psi was; high psi. force of entry of powder into the receiver, dust generation, clogging of the pipeline SOMEWHERE along its length. oft times the only way we could unclog the pipe was complete disassembly of the pipe. we switched to a system whereby the pressure vessel and pipeline itself was charged with low psi air; along the length of the vessel-pipeline as the powder transferred along this pathway. it worked thusly; we loaded the vessel as before, pressurized the vessel, opened the discharge port via solenoid valves, THEN as the powder exited the vessel and entered the pipeline a series of smallish air lines attached to the pipeline would systematically open (then close) charging the pipeline as the powder passed by each air injection point (along the pipeline's length).

I hope i explained the concept clearly enough. the point is; instead of one big psi injection at the source end of this delivery pipe, we used a whole series of small psi injection points along the delivery pipe. each air inject point would open/close sequentially in a cascading fashion, pushing product along its length.

hope this helps. check out lime, cement, etc. industries for such machinery.

Sorry for my ignorance!

What is the meaning of spring conveyor?

Regards,

Sorry for my ignorance! What is the meaning of spring conveyor?

Regards,