I dump mine into a 5 gallon metal bucket. After letting them sit for 4 days, I dump them in in paper bags for either the trash or green recycle bin.
Please, please for your safety, let them sit in a metal container for at least 3 to four days before putting them in your trash. I have had two neighbors have their garbage container catch fire due to charcoal ash dumped in them to soon. The first incident was 25 years ago. It was my next door neighbor and I saw the flames reflecting in my bathroom though the window late at night when getting up to pee. The garbage container had melted and caught his back porch on fire. Thankfully, I was able to wake him, get everyone out of the house and then we both were able to extinguish the fire.
The second incident was three years ago and the neighbor was not as fortunate. After dumping charcoal ashes in the garbage container, it caught fire, igniting juniper trees next to the house. It then melted the plastic framed windows and the fire entered the downstairs family room. Again, everyone was asleep but the smoke alarms woke everyone and all 5 escaped safely. The house did not fair as well and suffered significant damage. It took over a year for them to repair the almost $400,000 damage to the home.