That looks like a Bituminous stoker, like my Iron Fireman. does the red cabinet hold a coal hopper, that has the feed auger at the bottom?? Does the exposed auger you show actually run inside the 'air box' that is to the right of it in the second photo?? Is the burn pot in the rounded end of the airbox??
If all or most of the above is correct, then this is a bituminous coal stoker, these were meant to be installed in old hand fired boilers and furnaces, to take the place of the hand-feed grates and relieve the homeowners of haveing to tend the fire every 8-12 hours.. The shaker grates were removed, the airbox/auger assembly was slid into the boiler through the ash pan door. The firepot ended up at about the same level as the original grates were.. Then usually a ceramic cement, sort of like concrete was poured around the firepot to make a flat surface for the bituminous-coal Clinkers to form on and be removed [by hand] from the firebox..
The homeowner had to use 'Clinker Tongs' to reach in through the previous coal loading door and remove the hard chunks of Clinker from around the fire,, this was the 'ash' from a properly setup bituminous underfeed stoker.. There was no ashpan.
Post a photo of the fire pot.. I'm currious if it looks like my Iron Fireman's.
The Size of Bituminous coal is called stoker coal. it is about like small [anthracite's sizes] nut, pea and down to buckwheat.. Good stoker coal is less than 25% fines.. Bituminous coal is soft, so the pieces grinding against each other when shoveled, or trucked, creates lots of fine, sand-like powdery coal.. the stokers don't like these fines,, they can clog up the air holes in the fire pot grates, and clog up the auger if the fines get wet,, they turn into black mud..
You may be able to use buckwheat or pea size anthracite in this stoker, but you need to have an ashpan under the end of the burnpot, otherwise you will have a mess cleaning out the ash.. anthracite doesn't clinker like Bitum coal does..
I Burned Pea, Buckwheat and rice in my modified Iron Fireman.. it did well on anthracite.