8-hole COD digester

SH-108 type microcrystalline 8-holeCOD消解器The national HJ828-2017 standard analysis method standardizes the determination steps of chemical oxygen demand (COD) (Cr) for water quality, and strictly specifies the conditions and indicators such as heating digestion time, solution acidity, oxidant and catalyst dosage for the method. It is obvious that the determination of COD (Cr) in water quality has strict conditions, and any operation that violates these conditions will affect the accuracy of the determination.

The COD (Cr) constant temperature heater follows the basic principles of international standards (ISO) and the new national standard HJ828-2017, ensuring the digestion operation of reflux heating and micro boiling for 2 hours. The preparation and addition of reagent solution are consistent with the HJ environmental standard method, ensuring reliable and accurate analysis results.

The instrument adopts microcomputer technology for timed control of the heating electric furnace, which can simultaneously heat 8 250ml triangular flasks. To achieve the goals of energy conservation, reducing power load, and improving efficiency.

The instrument adopts a glass burr reflux tube instead of a spherical reflux tube, and uses air cooling technology instead of tap water cooling, which can save water and standardize the instrument.

According to the new standard HJ828-2017, the chemical solution preparation, operation, and COD calculation of the instrument can be improved by diluting titrants and oxidants for COD water samples below 50mg/L. For COD water samples above 700mg/L, the determination can be completed by diluting the water sample proportionally.

SH-108 type microcrystalline 8-holeCOD消解器Technical Specifications

1. Compliant with national standards: New standard HJ828-2017

2. Measurement range: 5-700mg/L; Determination after dilution of 700mg/L to 10000 mg/L water sample

3. Digestion time: 1 minute to 2 hours and 30 minutes (users can choose their own heating time)

4. Measurement error: The relative standard deviation of potassium hydrogen phthalate standard solution (500mg/L) shall not exceed 5.0%;

5. The relative standard deviation of industrial organic wastewater (500mg/L) shall not exceed 8.0%

6. Environmental temperature: ≤ 40 ℃

7. Cooling method: The upper inserted burr condenser tube is water-cooled with dual fans for dual cooling.

8. Sample size for digestion: 8 250ml conical flasks, heated and digested simultaneously in two rows

9. Heating power: ＜ 2800W (AC 220V, 50HZ)

10. Heating table: Microcrystalline glass heating table, overall structure of heating plate, overhead heating, easy to remove for replacement and maintenance.

Instructions for using the instrument panel buttons

1. The instrument panel has five buttons, namely the start button, up button, settings button, down button, and fan button.

2. There are a total of 6 indicator lights on the instrument panel, including the working indicator light, time indicator light, temperature indicator light, power indicator light, start indicator light, and fan indicator light.

3. After resetting the instrument, the fan is in the on state. The instrument fan can be turned on and off at any time. Press it once to turn it on, and press it again to turn it off. The switching process is repeated.

4. The start button can only be pressed when the work indicator light is on. After resetting the instrument, the heating device is in a stop heating state. Press the start button once to start heating the instrument, and then press the start button again to stop heating the instrument. Repeat the switch.

5. Press the setting button (if the instrument is in a heating state, it will stop heating), and the 6 indicator lights will light up alternately. When the instrument's working light is on, the start button can be pressed, but the up and down buttons are invalid. When the time indicator light is on, the heating time can be modified by pressing the up and down keys (once to add or subtract 10 minutes), and set to 150 minutes. When the temperature indicator light is on, the heating temperature can be modified by pressing the up and down keys (once to add or subtract 10 ℃) to set 500 ℃. When the power indicator light is on, the heating power can be modified by pressing the up key or down key (once to add or subtract 5%).

6. The instrument's time, temperature, and power parameters are automatically saved after being set. Automatically call upon next startup, no need to set it up again.

Instrument usage instructions

Before powering on the instrument, as much distilled water as possible should be added from the water injection port of the reflux pipe to ensure cooling effect.