Chemical reaction between two solid substances - comprises heating substances separately, then together, in fluidised beds under controlled temp. conditions improving energy balance

摘要

A process and plant for improving the energy balance of chemical reactions between two solid substances A and B mixed in the fluidised bed state incorporates heating A and B separately in the fluidised bed state in separate in separate enclosures to a temp. near the reaction temp. or below the max. temp. that they can tolerate without decomposition, and then bringing the heated substances together to form a single fluidised bed in a reactor. This fluidised bed is maintained at a mean temp. below that of reaction between the substances, the substances being brought locally to the reaction temp. The enclosures are pref. insulated columns with a grid for supporting the fluidised bed, a burner and a feed pipe for air for fluidisation at the lower part and a discharge pipe for gases of combustion and a hopper for feeding the powdered solids at their upper part. The reactor pref. consists of an insulated column with a central grid for the fluidised bed formed by the mixt., a discharge mechanism for the reaction product and pipes for feeding air for fluidisation and discharging gas at the lower and upper parts respectively. The plant includes heat exchangers for heat recovery. The process allows solid-solid chemical reactions to be carried out with excellent yields, which in other conditions can be carried out only with very low yields. Used e.g. for reacting Na Cl with silica to mfr. solium silicate,.