Cement clinker grinding method using vertical roller mill and apparatus
US6193176A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 9, 1998 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Feb 9, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P40/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of grinding cement clinkers and a cement clinker grinding apparatus having a vertical roller mill are provided. In the method, feed material is ground by a table and rollers. Next, substantially all the resultant ground material is taken out from an underside of the table and then converted to a separator for classifying the ground material by a bucket elevator. The resultant coarse powder provided by the separator is returned to a center of the table. In grinding, an pressing force of each of the rollers onto the table is selected so that a roller pressure per full sectional area of the roller ranges from 10 to 15 kg/cm.sup.2. Further, a circulation quantity of the coarse powder to be returned to the vertical roller mill is selected from 100 to 300% of the feed material charged into the center of the table. And the liquid of 0.5 to 3% of the feed material to be ground such as water alone or a mixture of water and diethylene glycol is sprayed on the only frictional grinding zone which is positioned outside a position where a relative speed between said table and each of said rollers is equal to zero, in the radial direction of said table. By spraying the liquid on the only…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.