Waste products of phosphates acid processing. Removal of fluorine compounds

1. MINISTRY OF SCIENCE AND EDUCATION OF THE REPUBLIC OF KAZAKHSTAN SOUTH KAZAKHSTAN STATE UNIVERSITY named after M.AUEZOV

2. Plan:

3. Conditions of sewage formation

4. The phosphoric acid produced by this way has low concentration (25-32 % of Р2О5), therefore it is evaporated up to higher

Phosphates
Phosphoric acid
52-54 % of P2O5
Fluorinecontaining
gases
Pulp
H2SO4
H2SO4
Extraction
Filtration
Evaporation
Solution of dilution
(16-20 % of P2O5)
Phosphogypsum
Waste
water

5. The process of wet process phosphoric acid production by dehydrative method includes the following stages:

6. Fig. 2 – A scheme of two-level absorption of fluorine-containing gases: 1 – a superphosphate chamber; 2, 3 – absorption

H2 O
Gas
1
4
Cleared gas
]
2
3

7.

Fig. 4.6 – A schematic diagram of a neutralization
installation of fluorine-containing waste water by
chalk: 1, 6 – bunkers; 2 – a conveyer; 3 – a storage of
chalk; 4 – a clamshell crane; 5 – a collector-balancing
tank; 7 – a reactor; 8 – a fan

8.

9. Recycling the sludge

1) from the point of view using valuable components
containing in them;
2) 2) with the purpose of environmental protection
from toxic fluorine and phosphorus compounds.