How to save charcoal after grilling food?

1. Extinguish the coals properly: When you're finished grilling, allow the coals to cool down completely before attempting to save them. Never add water to hot coals, as this can cause dangerous steam and ash explosions.
2. Use a metal container with a lid: Once the coals are extinguished, transfer them to a metal container with a tight-fitting lid. This will help to prevent oxygen from reaching the coals, which will slow down the combustion process and help to preserve them.
3. Store the coals in a cool, dry place: Choose a storage location that is both cool and dry, such as a shed, garage, or basement. High temperatures and humidity can cause the coals to deteriorate more quickly.
4. Avoid storing coals near flammable materials: Charcoal is a combustible material, so it's important to keep it away from any flammable liquids, gases, or other potential ignition sources.
5. Re-use the coals within a few weeks: Charcoal can lose its effectiveness over time, so it's best to re-use it within a few weeks of storage. If you're not planning to use the coals in the near future, consider disposing of them properly.

It's worth noting that re-using charcoal may not always be possible or advisable, depending on the condition and quality of the coals. If the coals have been exposed to moisture, have a lot of ash, or have been used multiple times, it may be better to discard them and use fresh coals for your next grilling session.