Present apparatus and methods for changing out carbon in an industrial carbon filter system, such as in a chemical process plant, include 50 to 2000 pound carbon canisters having openings at the top for receiving fresh carbon. Releasable attachment parts affixed to the canisters, such as nipples and flanges, are provided for connecting the canister into a process stream line for filtering the stream. A stream inlet nipple is usually provided near the top of the canister and a stream outlet nipple near the bottom.
The plant typically provides a roll-off box or the like for collecting spent carbon and sending it off to be revitalized and then re-used. The plant also usually provides a fork lift for moving canisters around the site. Typically a service provider is retained by the plant, however, to change out spent carbon and to refill the canisters with fresh carbon, upon demand and need. Spent carbon is shipped off-site to be revitalized. This spent carbon may be wet or dry.
Current service provider systems and methods typically include a truck, manned by at least two people, the truck having a hopper and vacuum apparatus. At least two people are required to set up the hopper and run the vacuum operation. In operation, in the prior art, canisters with spent carbon filter material are disconnected from their process streams and brought to a central site, usually proximate the location of a roll-off box or the like at a plant facility. A service provider vacuum truck is driven to the site. The at least two service people set up the hopper as the well as the vacuuming equipment. The upper lid of the canisters are opened, each in turn, and spent carbon is vacuumed out from the canister and into the provider's hopper. When the hopper is filled, (a hopper typically holds about 1500 pounds of spent carbon,) vacuuming is stopped and the hopper is frequently moved by the fork lift to a roll-off box, dumped into the roll-off box and returned to the proximity of the truck for further vacuuming. In a less favored system, because it entails higher risks, the hopper dumps its contents into one or more spent carbon container bags at the canister site. The bags are then tied off and moved to a location for collecting and shipping off site. (The possibility of the deterioration of the bags and resulting contamination of the site prior to shipping causes this option to be slightly less favored.)
The instant invention comprises an improvement to these known prior art systems and methods. The instant invention, at least in certain key applications, has been tested to determine that it is more cost effective and requires less equipment and fewer people and takes less time.
In preferred key embodiments of the instant invention, a canister is provided with two valved orifices. While one orifice may always be provided on top of the canister for re-filling the canister with fresh carbon, preferably a second valved orifice is provided by the instant invention on lower parts of the canister or on the bottom. This second orifice is preferably situated on the bottom and preferably includes a ball valve or the like for controlling an approximately four to six inch diameter opening. The same roll-off box and forklift provided by the plant, as discussed above, can be used in the instant invention. As will be shown, however, the instant invention can also be utilized with existing canisters.
In key preferred embodiments of the instant invention, a truck arrives with one person to the site of the canisters. (The truck may include vibration equipment for difficult canisters.) In this preferred embodiment one person lifts, with the fork lift, each canister up and over the top of the plant's roll-off box or the like. (Alternate embodiments are also disclosed below.) The service person opens a lower orifice on the bottom of the canister using a ball valve, and the spent carbon drops by gravity into the roll-off box. Alternately, the service person might pivot the canister, to invert it over the roll-off box, such that the spent carbon dumps from the top orifice.
The instant inventor's tests indicate that while it takes two people 8-9 minutes to vacuum a thousand pounds of spent carbon from a canister, it only takes one person two minutes or less to dump a thousand pounds of spent carbon into a roll-off box. (Note: the canister could also be dumped into saturated carbon containers or bags instead of a roll-off box. Again, use of such bags is slightly disfavored, as mentioned above, for incurring higher potential contamination hazards.)
The instant invention eliminates the need for vacuuming equipment, for the second or more service person and for the intermediate step of filling and emptying the service provider's hopper.
In the odd situation when spent carbon might resist dropping out of a canister by gravity, tests have indicated that the techniques of shaking, scraping and/or vibration can be successfully employed. The inventor's tests have demonstrated that a forklift can affectively shake a canister to cause sections of spent wet carbon that failed to fall by gravity, to break off and fall out of a canister. The inside walls of a canister can also be scraped, or squeegeed, by the service person. In addition, a vibrator, such as a vibrator used with a cement mixer, can be connected or inserted in the canister, possibly with a hand held prong inserted inside of the canister, to help ensure that all spent carbon is dislodged.
Again, preferred novel canisters of key embodiments of the instant invention have a second bottom valved orifice, which opens and closes. Although these canisters should be more expensive than the canisters of the prior art, that cost should be more than recovered by the enhanced speed and lessened cost of dumping rather than vacuuming, and also by the reduced cost of manpower and equipment.