[sane-devel] Ricoh SG 3100SNw scanner

[Stanislav]

You may want to try ricoh2 backend I've written recently for Ricoh SP100. It's available in the backends repo (https://gitlab.com/sane-project/backends). 
If you're lucky enough, your device has the same chip and it is supported.
But first you need to patch the source at least to detect your device (by adding your productid to get_model_by_productid).

Hopefully this will help,
Stanislav