Hi Ted,
  • In our Plant,  ASTM C150 Cement series were produced. However, the fineness (Blaine) is quite low, it's just below 3200 cm2/g.  AND this type of ASTM C150 cement was limited to: LOI, IR and SO3.  So I have to control raw material: Clinker, Gypsum (SO3) and limstone (LOI) in order that LOI <3.0%, SO3 <2.3%. (Certain Puzzolan is not used because of IR so high > 60%). Therefore We rarely change the raw material composition.

Question: How to increase the fineness of ASTM C150 cement if it was controlled by parameters:     Grinding Pressure (bar), separator (rpm), heat in the vertical mill (hot air from Kiln ), refluxed materials...or improve the equipment : damring heigh so on.

And We use the vertical mill (Loesche mill).

Could you give to me the experiences to control the fineness in cement...

Please help me!