Many productions have a coal/carbon fines as a by-product or as a feedstock:

coal factories with filter-cake – typical particles size is below 1mm
wooden chips productions with charcoal watered mixture – typical particles size from 10 to 900mkm
auto-tires pyrolysis factories  – typical particles size of black carbon is below 1..2mm
pet-coke producers (oil refineries) – particles size is 1..5mm

Translation coming soon.