Patent ID: 6019299
Filing Date: 2000-02-01
Classification: B02C,Y02P

Abstract:
A method for grinding cement clinker, comprising the steps of:grinding cement clinkers into particulate material without separating the ground material by a vertical roller mill;conveying all particulate material ground by the vertical roller mill in an upward direction by a conveyor;dividing the particulate material conveyed by the conveyor into a first part and a second part with respect to quantity of the ground material by a divider, a ratio of the quantity of the first part to the second part being variable according to a desired dispersion of size of particle of the cement product;directly returning the first part to the vertical roller mill without passing through any other step;grinding the first part into more particulate material by the vertical roller mill without any other intervening steps between the dividing step and the grinding step;separating only the second part into coarse powder and fine powder according to a desired size of particle of the cement products without any other intervening steps between the dividing step and separating step;producing the separated fine powder as products;directly returning the coarse powder to the vertical roller mill without passing through any other step; andgrinding the separated coarse powder into more particulate material by the vertical roller mill without any other intervening steps between the separating step and the grinding step.