About once a week I have to empty the ashes out of our wood burning fireplace insert. I noticed that there was always some wood coals not completely burned. This got my mind working and I came up with this system to reclaim the charcoal.
Step 1: Here's What You Need
All I do is collect the ashes from the fireplace and put them in a metal can and seal the lid. Then I let them sit for about 3 days, sometimes even a week before doing anything else. You want to wait a good while because the ashes can remain hot for a long time and you don't want to start a fire or burn yourself by sifting out the hot ashes.
All I do is pour some of the collected ashes out onto the screen and sift out the fines to leave the charcoal pieces. I store them in a five gallon pail. So far this heating season I've filled two five gallon buckets. I've used the reclaimed charcoal in my grill and it works great. You can see pictures of process but it's. Pretty self explanatory.