Loading & Handling of Activated Carbon 2

[H2O101]

I have an application in the North Carolina area that requires loading of several thousand tons of activated carbon into a set of reactors. I'm looking for either a company to subcontract the loading out to that's experienced in handling this, or somewhere to rent a conveyor or similar type of equipment.

The catch is that we don't want any method that will produce a lot of carbon fines, so we need something gental.

1) Any suggestions on the type of equipment? The initial thought is a conveyor, but renting one is proving difficult. Is there a way to gently blow it in?

2) Secondary to the above, does anyone know of where to rent this type of equipment in the central US east coast area?

3) Alternatively, are there any companies experienced in handling this instead that could be contracted to do the work?

We're a little hesitant to do this the 'hard' way by hoisting each individual bag over the tanks and cutting it open. Also, note that the tanks are ~30' above ground level.

Any help would be greatly appreciated.

 

[kchayfie]

Is it possible to fluidise the carbon and pump it in? I've seen that done with sand but I've never had to deal with carbon so far.

 

[runoff]

I have used US Filter but I am sure that they have subcontracted with someone. I will call my contact and ask. I like the fluidized operation and I have seen that used in a closed reactor SOP. Let me get back to you.

 

[waterexpert]

Pumping or blowing fluidised carbon will give you a lot of attrition, so you'll lose a lot as fines on your first backwash. It's not as tough as sand.

I've done this quite a few times, and I'm afraid for small jobs I have the bags slit into a vessel partially pre-filled with water, then top up with water once all of the media is in.

For bigger jobs, I have also dropped the contents of 1.5 m3 "big bags" into vessels prefilled with water through their bottom outlet. These techniques seem to give me the lowest losses.

Seán

http://www.seanmoran.co.uk

 

[bimr]

Talk to Calgon Carbon in Pittsburgh. They regularly do this. Sluicing with water is the most common method, but you can probably blow the carbon in pneumatically as well.

http://www.calgoncarbon.com/products/activated/carbon.html

 

[cub3bead]

How is your AC supplier delivering the product to site?

If they are using a "cement hauler" type carrier then you may be able to convey it pneumatically out of the hauler to your reactor using the on-board air compressor.

If you are receiving the AC in supper sacks there are a number of alternatives for placing the media.

I really hope you are not getting the media in 50# bags.

If you want to prepare a water/AC slurry you can use an eductor or an air operated, double diaphragm pump (Sandpiper or Wilden) to transfer the slurry from a temporary pool (i.e. kiddie swimming pool) to the reactor. You will generate a lot of water mess to deal with in this process.

Question: How do you differentiate the fines normally occurring in the AC with any generated during bed installation?

 

[H2O101]

Thanks for the replies everyone.

The fluidization aspect is intriguing as it will help in another process that can be done at the same time, allowing for us to kill two items at once. But we're not limited to that.

Waterexpert - That was the original plan, hoisting the bags over the tank and slicing them open. With the civil design on site though i.e. poor access to the tops of the tanks, etc, we have some saftey concerns. The tanks are almost 30' high with no walkway around the perimeter, just the tops of the walls.

cub3bead - we're getting the carbon in 1,100# bags. As such, a kiddie pool may exactly not be sufficient. I was thinking about something like a AODD pump...If we do this in some sort of holding vessel, to create the slurry we'd need to stay mixed, any ideas on how? A mechanical mixer would be the first thought but...

Also, does anyone know how much carbon we can get per gallon of water for the slurry?

 

[H2O101]

Also, we're not differentiating any fines, we just don't want to create more than we need to with a violent process.

 

[waterexpert]

I have always had to scaffold up to provide necessary access, and use cranage or winches to make light of the lifting requirements. I've never yet had a site where the designers designed in access for media charging.

Dropping big bags from a crane jib with one or two men in safety harnesses on top of scaffolding to open the chute on the bottom of the bag is quick and safe. They will need disposable overalls and dust masks.

If I were forced to pump, I'd probably look at a progressing cavity pump. They can pump grapes without breaking the skins...

Regards
Seán

 

[sbush]

We pump large volumes of GAC all the time. Very low attrition. We do both removal and installation. We can also repair or replace broken collectors and distributors. Lots of installations performed in North Carolina.

S. Bush

http://www.water-eg.com

 

[abcmex]

You can contact Calgon or a competitor as BIMR said if you want to subcontract the work. If you are interested in doing it yourself perhaps the link will help you>

http://www.eductor.net/liquid_hndlg_dry_ed.htm

RGS