You cannot use Bituminous coal in an Axeman Anderson stoker boiler.
The only Bit-burning stokers are SOME of the larger EFM boilers, Some Gentlman Janitor models.
Bit coal varies greatly from mine to mine.. Anthracite varies only slightly.
Most Bit coals will burn more like wood, the fire will spread through a hopper full of coal. anthracite waits to burn until after it leaves the hopper,
and is in the burn chamber/on the grate.
Anthracite burning stokers burn either rice [pencil eraser size], Buckwheat [navy bean to green olive size] and AxemanAnderson's burn Pea, [ripe olive to thumb size].
Bituminous 'stoker' size varies from breaker to breaker, but mostly it is around golf ball size, but Bituminous is soft, and breaks up and grinds to
fines [sand-like or powder] when run through an auger feed system,,
And because most Bituminous coal will clinker, which is melting of the ash into large clumps, most stoker systems can't handle the clinkers. So the
Bituminous stoker stoves require the owner/operator to use tools to physically remove the clinkers every day. Most Bit burning stokers do NOT have
and ashpan, but count on clinker formation so that the ash can be removed as solid chunks.
Most anthracite stokers have an ashpan, and anthracite coal only clinkers ocassionally, when burnt very hot..
If you want a stoker boiler, and have access to anthracite coal, then you have lots of choices of boiler brand, coal size etc.
If you want to burn only Bit coal, then you will have limited boiler/stoker makes and choices.