Instrument Introduction:
Chemical oxygen demand (COD) is a must-measure item in surface water, industrial wastewater, domestic sewage and other water bodies. It is an important indicator reflecting the pollution status of water quality by oxygen-consuming substances, and is also one of the key indicators for the country to implement total emission control. The "Determination of Chemical Oxygen Demand of Water Quality by Dichromate Method" (HJ828-2017) is currently recognized as the most accurate and reliable detection method. However, the reflux digestion process of water samples is a process with strict temperature and time control. If it is not mastered well, it will cause deviations in the analysis results.
Our company introduced this instrument with reference to the HJ828-2017 method. The PID temperature-controlled electric heater replaces the high-power electric heating furnace for heating, and air cooling replaces water condensation. It uses one-button start, automatic temperature control, 120-minute automatic countdown in the micro-boiling state, and automatic shutdown at the end of digestion. The operation method is consistent with the national standard method, one-button operation, automatic digestion, energy saving and consumption reduction, simple to use and easy to operate, and it also avoids the technical disputes caused by non-national standard methods for measuring COD.

Key technical specifications:

• Digestion element: The digestion hole is made of graphite material, and there are 12 digestion holes, all of which can be single-hole single-control;

• Heating element: adopts independent integrated winding heating mode design to make each heating hole heated evenly and thoroughly digested;

• Cooling method: Uniquely designed air-cooled reflux condenser with umbrella-shaped liquid filling port on the top for easy flushing;

• Use single-hole heating technology to heat the sample evenly, and do not use overall heating mode;

• Heating control program: Using PID temperature control technology, the error between the designed heating temperature and the actual heating temperature does not exceed ±1℃;

• The heating temperature and digestion time countdown can be set for each hole, and the digestion can be stopped automatically after the digestion is completed;

• During the digestion process, the actual heating temperature and reflux countdown time of each digestion hole can be monitored in real time through the front display screen;

• Digestion bottle design: The volume of the digestion bottle is about 300ml. After the digestion is completed, the titration can be done directly in the bottle without pipetting;

• It adopts a 7-inch LCD touch screen design, and a splash-proof cover is designed above the touch screen;

• Operation mode: After the parameters are set, it can be started with one button, and the digestion process is automatically completed (each digestion hole automatically reaches the set digestion temperature, automatically refluxes and counts down, and automatically stops), without manual supervision.