In order to use the Artec e+48u on Linux with SANE you must have the scanner firmware file and have the conf file containing the firmware file path.
Download the driver file here. Use your favorite file extraction tool and copy the Artec48.usb file to /usr/share/sane/artec_eplus48u/Artec48.usb
open /etc/sane.d/artec_eplus48u.conf and uncomment and modify the following line as necessary:
option artecFirmwareFile /usr/share/sane/artec_eplus48u/Artec48.usb
If necessary add your users to the scanner group using the following:
adduser USERNAME scanner