Chemical oxygen demand, also known as chemical oxygen demand, abbreviated as COD. It is the use of chemical oxidants (such as potassium permanganate) to oxidize and decompose oxidizable substances (such as organic matter, nitrite, ferrous salts, sulfides, etc.) in water, and then calculate the oxygen consumption based on the amount of residual oxidants. It, like biochemical oxygen demand (BOD), is an important indicator of water pollution level. The unit of COD is ppm or milligrams per liter, and the smaller its value, the lighter the degree of water pollution.

　　

Measurement steps:

　　

Calibration of ferrous ammonium sulfate: Accurately draw 10.00mL of potassium dichromate standard solution into a 500mL conical flask, dilute with water to about 110mL, slowly add 30mL of concentrated sulfuric acid, and shake well After cooling, add 3 drops of ferrous indicator solution (about 0.15mL) and titrate with ammonium ferrous sulfate solution. The color of the solution changes from yellow to blue-green to reddish brown, which is the endpoint.

　　

　　Chemical oxygen consumption analyzerThe main features are:

　　

1. No need to prepare reagents: Pre made reagent tubes made of chemical components required for COD testing in a certain proportion can greatly save the time required for reagent preparation;

　　

2. Time saving: The entire measurement process, including steps such as water sample digestion and colorimetric determination, takes less than 3 hours;

　　

3. Compact digestion device: The COD digester developed by Hash Company replaces the traditional COD reflux device and can simultaneously digest up to 25 water samples;

　　

4. Low secondary pollution to the environment: Micro reflux method only requires a small amount of reagents, and carefully designed reagent tubes can prevent the volatilization of organic matter and the escape of samples, ensuring the safety of the digestion process;

　　

5. Easy to operate and learn: The illustrated operation guide facilitates the mastery of COD analysis methods in a relatively short period of time.

　　

Scope of application of chemical oxygen consumption analyzer: detection of COD in various types of wastewater

　　

　　Chemical oxygen consumption analyzerTechnical specifications:

　　

1. Temperature control range: 50 ℃ -185 ℃

　　

2. Temperature control accuracy: ± 2 ℃

　　

3. Measurement range: 5-1000mg/L, 1000-3000mg/L (greater than 3000mg/L can be diluted for measurement)

　　

4. Measurement error: 5-100mg/L, error ≤± 5mg/L; 100mg/L to 3000mg/L, relative error ≤± 5%

　　

5. Anti chlorine interference: Cl-＜1000mg/L

　　

6. Dissolution time: 10-20 minutes

　　

7. Dimensions: Dissolver 350mm × 220mm × 120mm; Colorimeter 390mm × 320mm × 220mm

　　

8. Power consumption: Dissolver 900W (not exceeding) Colorimeter 10W