A dehydrator is a good idea, but don’t try it at home unless you want to risk ruining the device you put in if you don’t know what you are doing. Leave it to the pros as @Groomer said.
Rice is not best, but it is a decent drying agent. The problem is most water contains minerals and any drying will leave the minerals inside. In terms of absorption, here is how much moisture various substances absorb in a closed bag over an hour.
- Open-air sponge - 7.6 mL lost
- Silica gel - 6.1 mL lost
- Cat litter - 5.5 mL lost
- Instant couscous - 5.0 mL lost
- Instant rice - 5.0 mL lost
- Instant oatmeal - 5.0 mL lost
- Uncooked white rice - 4.0 mL lost
- Sealed-container sponge - 0.7 mL lost
