The high chlorine intelligent COD digester is mainly used for the determination of COD (chemical oxygen demand) in water quality testing. By using the digestion method, the organic matter in the sample is converted into an oxidizable form, and the COD value is calculated. The digestion process mainly includes the following steps:
1. Sample preparation
Firstly, it is necessary to sample and preprocess the water sample to be tested. For high chlorine water samples (i.e. water samples with high chlorine content), dilution or addition of chlorine inhibitors may be necessary to avoid interference of chlorine on the measurement results.
2. Add digestion reagents
High chlorine intelligent COD digesters usually require the addition of specific digestion reagents. Common reagents include potassium permanganate (KMnO ₄) and sulfuric acid (H ₂ SO ₄), which can decompose organic matter in water samples through oxidation and release the required amount of oxygen.
3. Set up a digestion program
The built-in program of the high chlorine intelligent COD digester will automatically adjust the digestion temperature and time. The general digestion process temperature is set between 150 ℃ and 200 ℃, and the digestion time is usually 15 to 30 minutes. The intelligent digestion device will automatically adjust the operating parameters according to the properties of the sample to ensure the best digestion effect.
4. Dissolution reaction
Under high temperature conditions, the digester achieves oxidative decomposition by heating the sample and conducting chemical reactions. During the digestion process, organic matter in the water sample is oxidized into carbon dioxide and water, and the amount of oxygen produced is proportional to the organic content in the water sample. The high chlorine intelligent COD digester will continue to heat up and maintain stable reaction conditions through an automatic control system.
5. Cooling and treatment
After digestion is completed, the digester will stop heating and cool down. The cooled water sample can enter the subsequent measurement steps, usually analyzed by colorimetric method to determine oxygen consumption.
6. COD concentration calculation
The amount of oxygen generated during the digestion process (oxygen consumption) is directly proportional to the content of organic matter in the water sample. The intelligent COD digester measures oxygen consumption and calculates COD values by combining calibration curves or algorithms.
7. Data output
The intelligent COD digester can monitor the reaction process in real time through internal sensors and control systems, and automatically output COD measurement results after digestion is completed. Users can quickly obtain the COD concentration in water quality through a display screen or connected computer.
summary
The high chlorine intelligent COD digester automates the COD determination process through heating, chemical reactions, control systems, and colorimetric methods. In the determination of high chlorine water samples, the equipment will take appropriate pretreatment steps to ensure accurate and reliable measurement results.