this looks to me like a industrial sized dehumidifying pack!

and look, it's already stated on the bag. "bla bla and static dehumidification approved...."

definately is a de-humidifier, but not necessary silica gel. can be some karbonat as well.

chemical composition 70% silicon oxide/silica gel SiO2, , 20% Alumina, Al2O3.... considered silica gel..... you would need to reheat the before use... oven at 150C will do or... microwave that exites the water molecules, There is usually some colour indicating gel.. be it blue to red.....deep blue to light blue

You would have to remove the silica gel beads from the cloth bag by removing some stitches and heat those beads in a tray... refill the bag and.. stitch back/ put into smaller containers...

Edit.. it appears to be to be clay type desicator with Si02 present... still regeration of the desicating function maybe possible.

wow...big bag u got there....

i would put it under the hot sun for an hour or so. with the sun this hot nowadays...
I won't put it in my microwave, unless that oven is no longer doing food stuff.

I would use it in my camera casing. just leave it at the bottom of the case. once a while just take it out to sun it.

Do it yourself. Goodness.