抄録
To conclude, it has been shown that it is technically possible to upgrade phosphate ore associated with car-bonates and chlorides gangue by calcination in a fluidized bed in a reducing environment, where nitrogen gas was used to create this environment in order to assist the decomposition of carbonates and hamper the formation of the insoluble oxides of sodium, potassium and magnesium without the extereme conditions of temperature and fine grinding of materials required for complete calcination of phosphates.
Results suggest that two flowsheets can be proposed for the treatment of Hamrawein phosphate by calcining (See Figs. 2 and 3).
Calcination of the complex phosphate matrix in an inert environment can decrease the amounts of the deleterious constituents to a level below that acceptable in the phosphate markets (See the fourth columns of Tables 3, 4 and 5 and the seventh of Table 6).
In addition to the above, chlorine gas can be obtained as byproduct, also when the gases of calcination were pass-ed through water, ammonia sulphate was detected in the water, therefore ammonia sulphates can be produced as byproduct as well.