Fire extinguishers must be completely empty before you recycle or dispose of them. If you have discharged your extinguisher for any reason, you cannot use it again until it has been properly recharged or replaced, even if it is still partially full.
Take the fire extinguisher to an open area, preferably outdoors. Open the garbage bag and put on the gloves.
Pull the pin at the top of the fire extinguisher. Point the nozzle inside the garbage bag and squeeze the lever.
Empty the canister completely. Seal the garbage bag and dispose of it with your regular household trash.
Contact your local fire station to have your fire extinguisher serviced and refilled. If you wish to dispose of it, check the pressure gauge to make sure all of the pressure has been released, remove the head of the extinguisher, and put it with your household garbage or take it to a recycling center.