Intelligent back-flow digest instrument

Intelligent back-flow digest instrument
Model ID: 6B-6C/6B-10C/6B-12S

6B series of the national standard COD intelligent back-flow digestion device is completely in accordance with the latest standard HJ828-2017 (instead of GB 11914-89) issued by Ministry of Environmental Protection, and its design is based on the basic principle. It can effectively ensure back flow and constant temperature control the 2-hour heating during decomposition, the preparation of reagent and addition all agree with Hj 828-2017 standards, ensuring accurate analysis results.



The instrument adopts microcomputer technology to make sequential control heating mode, at the same time, can heat 6/10/12 sets of 250 ml conical value type of large grind (straight type of large grinding mouth) full glass and back flow device; achieving the purpose of energy saving, reducing power load and improving efficiency.

This instrument uses glass burr returned tube instead of spherical returned tube, and to use tap water cooling and  air cooling to replace water cooling technology which can save water and reduce the place, also, can make the instrument standardization, at the same time it improves the security of the instrument; The heating floor adopts design concept of fashionable microcrystalline optical panel, which not only can improve the accuracy and precision of sample’s digestion, and improve the aesthetic degree of the product.

Reagents and materials, analytical steps and the results of the COD used by the instrument fully comply with the latest national standard HJ 828-2017; Note: for determination of water samples with50mg/L COD, when the sample concentration is low, sampling volume can be appropriately increased; For determination of COD water > 50 mg/L, can be diluted by titration agent and oxidant to improve accuracy; For COD water > 700 mg/L, should be diluted water concentration to complete the result test; when the COD results< 100 mg, reserve to integer, when the COD results l00mg/L, keep three significant figures; for water samples with high chloride ion content, refer to appendix A method of the latest national standard HJ828-2017 to make judgment and measurement.

-Double fans implement convection cooling, which can be independently controlled, and the cooling effect is remarkable

-Big LCD shows in English, and time, power is adjustable, the users can modify, setting, save by themselves

-Using microcrystal heating panels and infrared heating mode, making heating fast and uniform, and service life longer

-After completion of digestion, the instrument will automatically ring to remind and stop heating

-Water-saving, power-saving, thermal radiation is small, and the space usage is small

-Simple operation, which can effectively reduce the cost and improve working efficiency


Technical specifications

Measuring range

16~700mg/L700~10000mg/L(need to dilute water sample)

Measuring time

150   minutes (can set time according to the requirement of users)

Measuring error

Potassium biphthalate standard solution (500mg/L)   and the relevant standard deviation are not more than 5.0%; industrial   organic waste water (500mg/L) and relevant standard deviation are not more   than 8.0%

Environment temperature


Display mode

Liquid crystal display

Type of cooling

Air cooling (double fans)

Batch sample

6 pieces/batches

12   pieces/batches

12 pieces/batches

Digestion time

Can set time according to the requirement of   users, 1-999 minutes

The setting of fan

Self-motion/manual operation

Working power supply

1200W (AC 220V±22V, 50HZ)