Simultaneous production of cement and electrical power by fluidized bed combustion of pretreated gangue

A new type of low-energy cement has been obtained in the temperature range 850-950°C. Calcareous material is added to wet coal gangue and treated at less than 100°C; it is formed into pellets less than 6 mm in diameter. These pellets may be burnt at 850-950°C, which is the normal operating temperature of a small fluid bed boiler. The resulting slag may be ground to produce a new type of high early strength cement. This technology saves a great deal of energy and it is profitable, and it will also greatly reduce environmental pollution from fluid bed slag, SO₃ emission and fly ash.