How do you dry a silica desiccant?

You can spread the silica dessicant (whether in dessicant packs or loose) in a thin layer on a baking sheet and heat in the oven at about 250F for one to three hours. Do not set the temperature too high as they will start to lose their effectiveness. If they turn black, they have been overheated. Temperatures under 280F should be fine. If the crystals are loose, they will dry more quickly.

Dessicant that changes colour from blue (dry) to pink has been doped with cobalt chloride, which could be a carcinogen, so keep the dessicant packs intact if the silica gel has a blue, purple or pink colour.

http://en.wikipedia.org/wiki/Desiccant

http://en.wikipedia.org/wiki/Silica_gel