Coarse and fine grinding of cullet in a Pfeiffer MPS roller mill

The beneficiation of waste glass, e.g. for the production of container glass, aggregates for conventional and fine ceramics, or high-grade fillers, is steadily gaining in importance. Depending on the application, the requirements on the particle size range of the processed glass will vary. The grinding of cullet in the Pfeiffer MPS mill, coupled with in-process drying, permits the production of glass powder and, alternatively, the simultaneous production of glass powder and glass particle sizes in the range 0.1-1.0 mm. Successful trial grindings involving residual products from the bottle-bank glass processing, such as fine glass, ceramics, stones and porcelain, have been conducted in the MPS 32 test mill. During coarse grinding, for example, it proved possible to separate out paper residues. Wear values of 20-30 g/t have been recorded in practice when fine grinding cullet in MPS roller mills. The processing costs for glass powder are less than 20 euros/t. If glass powder and glass sand are produced at the same time, these can be reduced to less than 10 euros/t.