FIELD: process engineering.
SUBSTANCE: invention relates to production of high-strength and high-early-strength alite Portland cement. Stock with high content of CaCO3, 92-98% and quartz sand with silica content of 92-98 is fed. Note here that every said component gets to its processing line. Said production line comprises limestone or chalk screen to separate to 600 mm lumps and 25 mm lumps, hammer two-rotor crusher to grind the lumps to 25 mm fraction with grinding factor of 15-20. This comprises tank with 25 mm fraction of CaCO3 to be subjected to preliminary drying. Similarly, in the case of quartz sand, vibrating screen for separation of impurities are used as well as sand tank. Every line for CaCO3 and sand is equipped with two drier drums, two ball mills to grind to 0.01 mm fraction with drying to 0.5% moisture content, two mills to grind to particle size of 1 mcm and two service bins. Limestone or chalk and quartz sand are fed from the bins via batchers for annealing separately in annealing ducts and mixed in zigzag channels. Swirling gas flow of calcium oxide mixes said calcium oxide with annealed sand falling from above at smaller speed onto has flow with calcium oxide to produce required calcium oxide-to-silica ratio of 3:1 required for alite formation. Produced mix at 1450-1480°C gets into hot forming press. In every pressing cycle of 20 s 30 mm thick 500 mm diameter plate of clinker is produced. Downstream of refrigerator chamber clinker plate at 50°C is fed into hammer crusher and, then to grinding mill to be ground to 0.01 mm fraction and jet grinder for grinding to 0-30 mcm fraction, Portland cement with content of alite of 70-90% is thus produced.
EFFECT: accelerated non-polluting process, higher strength of Portland cement.
2 cl, 1 dwg, 1 tbl
