Sodium Chloride Evaporation Project of a Chemical Enterprise in Qidong, Jiangsu
Sodium Chloride 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 chloride 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 108 ° C, which is suitable for MVR evaporation. The physical properties of the data are as follows:
Sodium chloride solubility
|
Item |
Maximum dissolved mass in 100g water at the following temperatures / g |
|||||||||||
|
0 |
10 |
20 |
25 |
30 |
40 |
50 |
60 |
70 |
80 |
90 |
100 |
|
|
Sodium chloride |
35.7 |
35.8 |
36 |
|
36.3 |
36.6 |
37 |
37.3 |
37.8 |
38.4 |
39 |
39.8 |
Sodium chloride boiling point
|
Item |
Boiling point / ℃ of the solution at the following concentrations (g / 100g water) |
||||||
|
10 |
25 |
40.7 |
50 |
75 |
100 |
222 |
|
|
Sodium chloride |
101.6 |
104.6 |
108.8 |
|
|
|
|
Project
|
No |
Item |
Introduction |
|
1 |
Name |
Sodium Chloride Evaporation Project of a Chemical Enterprise in Qidong, Jiangsu |
|
2 |
Address |
Jiangsu Qidong |
|
3 |
Treatment of wastewater industry |
Chemical high salt wastewater |
|
4 |
Capacity |
5t/h sodium chloride MVR evaporation treatment |
|
5 |
Process Technology |
Raw water - preheating system - MVR evaporation concentration - crystallization system |
|
6 |
Process introduction |
The project is chemical wastewater, in which the organic matter content is high.As the COD is high, the condensed water need to be treated by biochemical treatment.Since the organic matter is enriched in the evaporator, the boiling point of the material increases and the evaporation decreases.The efflux part of the mother liquor enters the subsequent biochemical treatment system to ensure stable operation of the evaporator. |
