Huazheng HZJY880 Biochemical Oxygen Demand BOD5 Analyzer
Instrument Introduction And Scope Of Application
Biochemical oxygen demand BOD5 is a mandatory test item for water quality assessment and an important quality indicator for measuring the pollution of water by organic matter.
The BOD5 analyzer is a new type of instrument that uses the air pressure difference method to determine biochemical oxygen demand. It can accurately provide measurement results comparable to those obtained by the chemical dilution method. It features intuitive readings, clear biochemical reaction curves, and convenient use and maintenance, making it an ideal tool for analytical work. It can be widely used in water quality monitoring in environmental protection, petrochemical, medical and health, teaching and research departments.
Working Principle
1. Basic principles of B0D5
Biochemical oxygen demand (BOD5) refers to the amount of dissolved oxygen consumed or required by aquatic microorganisms to decompose organic matter in water under specific conditions through their reproduction and respiration. The BOD5 value in water is usually expressed as the amount of dissolved oxygen (mg/L) consumed by a sample placed at 20°C for 5 days, denoted as "BOD5".
Measurement Principle
A stirrer is placed in an incubator, and a predetermined volume of water sample is poured into the culture flask according to the pre-selected range and measurement scope. The flask is then continuously stirred. The incubator temperature is controlled at 20℃±1℃, and the water sample is cultured for five days after reaching this constant temperature. Sufficient dissolved oxygen must be maintained in the culture flask. Organic matter in the sample undergoes biological oxidation, transforming into oxides of nitrogen, carbon, and sulfur. During this process, the only gas escaping from the water sample, carbon dioxide, is absorbed by sodium hydroxide (or potassium hydroxide). Therefore, the decrease in air pressure in the flask corresponds to the amount of dissolved oxygen consumed by the microorganisms. Thus, the BOD5 value of the sample is directly proportional to the degree of air pressure reduction in the flask. The BOD5 value can be obtained by measuring the change in air pressure. Increasing or decreasing the amount of sample taken will increase or decrease the pressure reduction value. This allows the operator to accurately measure a wide range of BOD5 values without complicated dilution procedures. Changes in air pressure in the culture flask are detected by a semiconductor pressure sensor, and the BOD5 value and biochemical reaction curves of each sample are displayed cyclically on the monitor.
Main Technical Specifications
1. Measurement range: 0～4000 mg/L (dilution is required when the BOD5 value exceeds 150% of the measurement range);
2. Number of samples to be measured simultaneously: 6 samples each time;
3.Accuracy: Complies with the national standard "HJ 505-2009"《Water Quality - Determination of Five-Day Biochemical Oxygen Demand (BOD5) - Dilution and Inoculation Method》 and "GB/T5750.7-2006" 《Standard Examination Methods for Drinking Water - Comprehensive Index of Organic Matter》;
4. Display: The touchscreen displays real-time BOD5 readings, with results directly shown in a list. Data tables are automatically saved for easy retrieval.
5. Operation: Touch screen settings, independent setting of measurement range for each sample, clear and concise selection of items, diverse modes and simple operation;
6. Equipped with printing function and USB interface;
7. Cultivation temperature: 20℃±1℃;
8. Power supply: AC 220V±22V 50Hz±0.5Hz;
9. Power consumption: Instrument ≤ 50W, constant temperature chamber ≤ 300W;
10. The instrument can save the BOD5 values and real-time biochemical results of the 6 samples analyzed last time;
11. Measurement method: Differential pressure method;
12. Main unit weight: 5kg.
Special features
It has a built-in printer function. It can automatically print parameters, allow users to set the printing frequency, and print historical and current data at any time.
A wireless mouse can be used to operate the machine, making operation more convenient and avoiding inaccurate data measurements caused by repeatedly opening and closing the temperature chamber door during the measurement process.
The full touchscreen settings allow for convenient and quick parameter adjustments. The color screen display shows BOD change curves in different colors, as well as real-time BOD values during the measurement process.
Data can be exported via a USB flash drive.
Mercury-free devices ensure the safety of laboratory personnel when operating the equipment.
Large-capacity storage, capable of permanently storing 10,000 data entries.
The constant temperature waiting time can be set by the user to adapt to various ambient temperature requirements.
The culture period can be set from 1 to 30 days to meet different experimental requirements.
Detailed data on the curves can be queried through the data query function, experimental curves can be generated at any time, and the experimental process can be traced back at any time.