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. Equipment overview

Public and emergency broadcasting systems in the installation building project are based on the development trend and characteristics of the intelligent construction industry, combined with the functions and applications of building intelligent technology, and the work tasks of building 5A subsystems. The comprehensive application and expansion of various technologies such as network communication, comprehensive wiring and system integration, and multi -level satisfying the installation and operation of the building intelligent equipment of technicians and vocational colleges, building equipment installation, automation control, computer network and communication system engineering, etc. Relevant professional systems and principles, skills display, work task design and planning, tr--ning, process and results assessment, assessment, appr--sal, competition, engineering project design and graduation design, etc.; (Installation, wiring, wiring, programming, debugging, operation, m--ntenance and m--ntenance, etc.), design planning, communication, teamwork, efficiency awareness, and innovative thinking, etc., at the same time cultivate their rigorous work style and good professional literacy.

2. Technical indicators

(19) Power input: single -phase three -line (third party ground ground), AC220V ± 10%, 50/60Hz;

(20) Safety protection: grounding, leakage (action current ≤30mA), overvoltage, overload, short circuit;

(21) The power consumption of the whole machine: ≤300W;

Dimensions (wide × height × depth): 1060mm × 1900mm × 800mm (industrial aluminum profile bracket);

3. Tr--ning project

1) System installation, wiring, wiring, programming, commissioning, operation, m--ntenance and m--ntenance;

2) Setting, detection and exclusion of line f--lure;

3) Understand the basic working principles, basic configuration and system structure of the public broadcasting system;

4) Manual broadcast operation: Release notice, meetings and play music;

5) Automatic broadcast programming: Realize the bells of the campus, the timing eye key operation, and the time play background music;

6) Manually start emergency broadcasting;

7) Quickly start the equipment power supply and partitions and voice evacuation people;

8) Scenario tr--ning of public broadcasting systems;