Electrolytic method treatment device

1. Understand the process of processing the processing of chromium -cont--ning electroplating wastewater.

2. Deepen the understanding of the basic concepts of the experiment and improve theoretical and practical knowledge.

principle:

In acidic chromium -cont--ning wastewater, chromium is m--nly in the form of CY2O7 = in form, but there are also a small amount of Cyo4 =.

Use iron plates as yin and anode, and add a cert--n amount of salt to the wastewater to increase the conductivity and activate the anode. Stir with compressed --r and electrolytic processing at low voltage DC power. Under acidic conditions, iron anode is used to dissolve, generate di -valence iron ions into the wastewater, and restores hexavalent chromium into tri -chromium. When triad chromium pH> 5, generate chromium hydroxide precipitation, separate Exile the water after precipitation.

Anode reaction: Iron lost electrons into binary iron, ions enter the wastewater.

Fe-2E → Fe ++

The two -valent iron ion is a strong reducing agent that restores the hexavalent chromium in the wastewater into a three -valent chromium.

CY2O7 =+6Fe +++ 14H+→ 2cy3 ++ 6FE3 ++ 7H2O

CYO4 =+3Fe +++ 8H+→ Cy3 ++ 3FE3 ++ 4H2O

Cathode reaction: Hydrogen ions discharge on the cathode and become hydrogen. At the same time, a small amount of hexavalent chromium is discharged on the cathode to become hydrogen. It promotes the pH value in the wastewater to gradually increase, resulting in separation of chromium hydroxide and chromium hydroxide and separation. Chromium hydroxide is easily precipitated at 5, and at the same time, the FE3+in the wastewater generates the precipitation of iron hydroxide.

CY3 ++ 3OH -→ Cy (OH) 3 ↓

Fe3 ++ 3oh - → Fe (OH) 3 ↓

After precipitation, the emission standard can be met.

1. M--n use:

1. Familiar with the operation of the pump, master the method of experimental organization, and understand the principle of experimental operation;

2. Learn the measurement method of the characteristic curve of the pump, and correctly master the use of diagram processing experimental data.

2. The m--n indicators and parameters of the experimental table

1. Environmental temperature: 0.5 ～ 40 ℃

2. Corresponding pump model: FS103

3. ** Yang: 11

4. ** traffic: 4.5

5. Pump inlet pipe diameter D: 32 mm

6. Motor rated power: 370 W

7. Motor rated speed: 284 ride/minute

8. Equipment Dimensions: 1200mm × 450mm × 1800mm,

9. Work power: AC220V ± 10%, 50Hz, single -phase three -line system, 370W power, safety protection: ground protection, leakage protection, overcurrent protection

3. M--n configuration:

1. 304 st--nless steel experiment water pump;

2. Class 0.4 precision positive and negative pressure gauge;

3. Pole board traffic meter;

4, pressure difference;

5. With white PE material back to the water tank;

6. Calculate the measuring box,

7. ABS string, and pipeline the road,

8. Copper valve