We do not now, nor have we ever used desiccant products in our beans or for any other purposes.
If desiccants are used at all for beans, I would guess it would most likely be in the high moisture growing areas of Michigan and/or North Dakota.
Their bean crops typically contain 16% or more MC (moisture content) at the time of harvest. They employ fans, dryers and dehumidifiers to bring the MC down and/or remain stable.
Personally, I’ve never heard of desiccants being used for beans in any growing areas.
I would think that it would be more common in grains, but I do not know.
I’ll see if I can find out more information on possible uses when I have a little time.