SU617448A1 - Method of chemical enriching of magnesium-containing phosphate raw material - Google Patents

Description

(54) METHOD OF CHEMICAL ENRICHMENT OF MAGNESIUM-CONTAINING PHOSPHATE RAW MATERIALS

a solution of sulphate, a magp and a precipitate of calcium sulfate crystals, which provide for the data of tloBy x filtration of the suspension with a high productivity - 1500 for dry washed sludge. After filtration, a part of the solution (15-25% of the total amount) is removed for processing into complex fertilizers by known methods, and the rest of the mass is returned to the shift with phosphate. According to the method, the degree of MgO recovery to the solution is 75-80%, carbonates 85-95%. 0.4-0.6% of MgO remains in the treated phosphate. The transition of phosphate to the liquid phase is 0.2-0.5% of the total amount of PjOs.

Example 1. 100 kg of phosphate composition,%: PjOs 22; CaO 39.1; MgO 4.6; COs 9.3 are displaced by 278.2 kg (L: 1) of a magnesium sulfate solution with a concentration of 22i%, containing 0.19% P2O5. Subsequently, the suneneisia is sent to the reactor, to which 21.8 kg (92% of stoichiometry for the decomposition of carbonates) of 92% sulfuric acid is fed. Extraction of magnesium proceeds for 5 minutes at 90 ° C, 4.15 kg of MgO (90% of the initial) and 0.4 kg of PgOs are removed in the solution; 21.6 kg of PgOs and 0.45 kg of MgO remain in the solid phase.

377 kg of phosphorite suspension is filtered, the filtrate is 46.6 kg (28% MgSO4) and directed to further treatment, and the rest of it, 205.4 kg, is fed into the mother liquor collection. Phosphorite is washed with water, and 78.2 kg of wash water is also collected in the mother liquor collector, from which, after mixing with the filtrate, they are sent to the system head for the suspension of phosphorite. The filtration rate of 1500 dry washed precipitate.

125 kg of demagnetized phosphate with a moisture content of 20% is sent to the sulfuric acid extraction using the dihydrate or hemihydrate method and extracytio phosphoric acid is obtained with a concentration of 25-27% (or 32-37% P2O5) or dried and get marketable product - magnetized phosphorite.

The production part of the filtrate (46.6 kg), corresponding to the amount of magnesium extracted from phosphate in the process of dehydration, is shifted with fertilizer solutions or pulp or organic fertilizer or processed by other known methods. For example, displaced with solutions of mioammonium phosphate, ammonium sulfate, potassium nitrate and get kg of goodness

of the type “dissolved in the ratio N: P205:: K2O: MgO 10; 5: 20: 6.

Example 2. 100 kg of phosphorite of the composition specified in example 1 are shifted for 30 minutes at 400 kg of 10% magnesium sulphate () solution containing 20 kg of sulfuric acid. 4.15 kg of MgO and 0.4 kg of P205 are recovered in the solution, 21.6 kg of P2O5 and 0.45 kg of MgO remain in the solid phase. The suspension of phosphate (496.63 kg) is filtered (in this case, the precipitate is not washed). Filtration rate reaches 3500 Kr / Mf - 4 on dry unwashed residue. 88 kg of filtrate (12% MgSO4) is recycled into complex fertilizers, the rest

the amount (283.6 kg) is mixed with 117.4 kg of water and 20 kg of P25O4 and used again in the process.

125 kg of phosphorite with a moisture content of 20% direct the extraction. Productional

Part of the filtrate (88 kg) with a concentration of 12% MgSO4 is shifted with extraction phosphoric acid, sent for ammonization, and 12 kg of magnesium ammonium phosphate are obtained.

Claims (2)

1. USSR author's certificate number 366177, cl. S 05B i 1/08, 1973 2. Chepelevetsky M. L., Brutskus E. B. and etc. Chemical enrichment of Karatau phosphorites from the Chulak-Tau deposit. Reports on the scientific and technical work PIZIF. Experience exchange. M., Goskhimizdat, 1957, p. 15-17.