METHOD OF THERMAL PROCESSING ASH-RICH SOLID FUEL Russian patent published in 2009 - IPC C10B53/06 C10B49/20 

FIELD: chemistry.

SUBSTANCE: method of thermal processing ash-rich solid fuel with obtaining cement clinker involves mixing ground hard-backed and heated solid fuel with a prepared mixture of raw components, semicoking the obtained mixture in the presence of a solid heat carrier, releasing a gas-vapour phase and solid product of semicoking and their separation. The method is distinguished by that, the solid fuel used is slate coal containing (dry substance), wt %: CaO 1.89-30.47, SiO₂ 17.12-38.52, Al₂O₃ 4.75-12.16, Fe₂O₃ 3.9-6.55, MgO 0.1-2.11, SO₃ 0.76-4.8, p.p.p.28.0-49.6 or its mixture with raw components, where the latter is obtained from limestone and/or chalk stone and/or gypsum, gaize, pyrite cinder, tripoli, technical alumina, and clay, taken in amounts which provide for obtaining a mixture containing (dry substance), wt %: CaO 43.11-49.42, SiO₂ 5.52-8.73, Al₂O₃ 0.44-3.22, Fe₂O₃ 0.22-3.83, MgO 0.1-2.0, SO₃ 0.1-9.97, p.p.p.34.52-41.0. After semicoking, the solid product is subjected to oxidative decomposition at 800-1100°C with subsequent separation of the obtained gaseous and solid products, and these solid products are taken directly or after mixture with raw components and decarbonisation of the obtained mixture for burning at 1300-1500°C with subsequent cooling of the cement clinker obtained from burning. Solid fuel and the said mixture are taken in amounts which provide for obtaining portland cement clinker, after processing, containing, wt %: CaO 61.8-71.0, SiO₂ 19.8-24.6, Al₂O₃ 4.4-7.7, Fe₂O₃ 3.4-7.7, MgO 0.6-5.4, SO₃ 0.7-4.6. Preparation of the said mixture of raw components involves grinding, drying, heating as well as possible decarbonisation of the whole or part of the mixture of raw components at 750-1100°C. Decarbonisation is done using heat from gaseous products of burning and/or semicoking, and/or oxidative decomposition, and/or heat from solid products of the latter.

EFFECT: increased degree of utilising heat energy, reduced amount of wastes and obtaining extra products when processing slates.

12 cl, 19 ex, 62 tbl, 1 dwg