Treatment of sodium sulfate wastewater from a flame retardant enterprise in Jinan
Sodium sulfate MVR Evaporation Crystallization Project
The organic matter of high salinity organic wastewater varies greatly according to the production process, and the types and chemical properties of the organic matter are quite different.The salt substances are mostly Cl-, SO42-, Na+, Ca2+ ,etc. If it is directly discharged, it has a great impact on the environment; and it is difficult to handle in the biochemical treatment process. These ions are essential nutrients for microbial growth, which can promote enzyme reaction and maintain membrane balance and regulate osmotic pressure.However,if these ion concentrations are too high, it will inhibit and toxic the microorganisms. High salt concentration, high osmotic pressure will cause dehydration of microbial cells and protoplast separation; salting out reduces dehydrogenase activity; high chloride ion has toxic effect on bacteria; High salt concentration and increased density of wastewater will let the the active mud to float and drain, which seriously affects the purification effect of the biological treatment system.
For high salt water, it mainly comes from the following aspects:
1. High-salt wastewater from chemical production processes;
2. From chemical wastewater treatment;
3. High-salt wastewater from freshwater recycling process.
For Sodium sulfate high salt water, the solubility of the material is low, and the boiling point is lower in the case of saturated solubility.The boiling point under atmospheric pressure is low, which is suitable for MVR evaporation. The physical properties of the data are as follows:
Sodium sulfate solubility
|
Item |
Maximum dissolved mass / g in 100g water at the following temperatures |
|||||||||||
|
0 |
10 |
20 |
25 |
30 |
40 |
50 |
60 |
70 |
80 |
90 |
100 |
|
|
Sodium sulfate |
4.5 |
9.6 |
10.2 |
27.9 |
40.8 |
48.4 |
46.7 |
45.3 |
44.1 |
43.7 |
43.9 |
42.3 |
Sodium sulfate boiling point
|
Item |
Boiling point / ℃ of the solution at the following concentrations (g / 100g water) |
||||||
|
10 |
25 |
40.7 |
50 |
75 |
100 |
222 |
|
|
Sodium sulfate |
100.6 |
101.6 |
|
|
|
|
|
Project
|
No |
Item |
Introduction |
|
1 |
Name |
Treatment of sodium sulfate wastewater from a flame retardant enterprise in Jinan |
|
2 |
Address |
Shandong Jinan |
|
3 |
Treatment of wastewater industry |
Aluminum flame retardant |
|
4 |
Capacity |
4t/h sodium sulfate MVR evaporation treatment |
|
5 |
Process Technology |
Raw water - preheating system - MVR evaporation concentration - crystallization system |
|
6 |
Process introduction |
The project is the evaporation and crystallization treatment of aluminum-based flame retardant wastewater. The material mainly contains sodium sulfate and contains a small amount of zinc borate. The system uses MVR to evaporate and crystallize, and uses a two-stage piston centrifuge for salt separation. However, due to the presence of a small amount of zinc borate, the salt crystals of the material become finer in the later stage of evaporation.Cooling crystallization will be adopt to treat the dischared mother liquid to ensure smooth salting of the material. |
