Removing/handling solidified chemicals from drums

[ferdia]

Looking for ideas to help remove partially solidified chemicals from plastic drums. Chemicals have solidified in the bottom 12" of the drum, neck of drum is narrower than the base, type of chemicals are Urea, sodium chloride etc
in addition these chemicals are also clumping throughout the drum causing downstream handling issues

 

[Ashereng]

I am not sure if you have provided enough information for a thorough answer, but here is my 2 cents worth:

1) vibration usually helps prevent clumping
2) solvent usually helps by lowering viscosity, which can help reduce clumping
3) recirculation of material also helps - I guess this is sort of like vibraton
4) temperatuer usually helps by lowering viscosity, which can help reduce clumping

You did not mention whether this is a batch or continuous system, or whether the clumping is more pronounce at one time versus another, or how big a drum is, so please take my response in context.

 

[ferdia]

Thanks for your 2cents worth,
Process is a batch system initially then runs into a continous process,
Drums are 50kg
Solvent use is not an option
Vibration of drums as abstep prior to dispensing could be viable
On site storage is in an ambient warehouse 20C+-4C although transport in is not
I had thought of looking at materials recieved in winter/summer to see if there was any indications
Also thought of changing the drum shape and size, the molecular structure of the materials is such that they will always tend to compact, the idea would be to reduce/minimize this impact

 

[Eltron]

With those chemicals you will have problems with clumpung, given your working conditions. I would lean towards changing the drum shape and size. That will be the simplest solution to your problem. Assuming, of course, that all you're worried about is getting the stuff out of your buckets.

 

[Ashereng]

You are welcome ferdia.

Is the chemical a "powder" that solidifies? I am not familiar with urea, but sodium chloride is salt (right?). Like with ingress of moisture (from the air)? Or, is it a straight compaction problem?

If solvent is not an option, how about air (or suitable gas) to try to "fluidize" the content in the drum. A drum/vessel with large surface area and relatively "short" height may help the chemical to flow better?

If it is a solids system, how about a hopper to screw feeder system? You can vibrate the hopper part - it can be isolated from the feeder by flexible bellow/plastic type tubing.

Not sure if this is worth 2 cents, but I thought I'd try.

 

[kenvlach]

I'll also volunteer my 2 cents worth:

1st ¢) Ask supplier whether chemical is available with anti-caking additive. If so, check compatibility with your end use.

2nd ¢) Try storing the containers (securely closed) upside down. Then, when opening, geometry & gravity will be in your favor.

Ken

 

[ferdia]

Materials are sterile so introducing air not an option
Materials are currently filled by supplier in open air so possibility of moisture causing compaction.
Going to do a trial with filling under nitrogen/dry air
We've also been given an alternative size/shape drum and we may invert/rotate current stocks and see if this improves material state.
Hopper/screw feed would be an option if we could get the materials out of the drum to start with

In relation to anti caking additives and because of the nature of our product we can't avail of this option, most anti caking materials are polymer based and this material is pure

Thanks for all your two cents worth, any other ideas greatly appreciated

 

[Ashereng]

ferdia,

"Hopper/screw feed would be an option if we could get the materials out of the drum to start with."

"We've also been given an alternative size/shape drum and we may invert/rotate current stocks and see if this improves material state."

If you do these two in concert, it may work.

One of the summer jobs at a plant I worked at has a summer/coop student making sure the weight&dump scale did not get "clogged" up. I am sure he/she also had other tasks, like sampling, temperature reading, guage reading, etc.

It's a thought.

I think I need to up my rate to 2.5 cents now - 2006 is coming and so is inflation. Hee Hee.

 

[bimr]

Not really clear what you are doing.

How are the chemicals normally removed from the drums? How do you keep the material sterile?

Why don't you just switch to liquid products. It would be easier to meter the product.