Differential Pressure BOD Measuring Instrument

Put Water sample and water that have received Pre-processing inoculation into culture flask, meanwhile, put absorption unit of carbon dioxide ----- NaOH into the suction cup of the incubator, then seal the incubator and put it into 20±1℃ thermostatic cabinet. There will be biochemistry reaction occurring to the water samples while being mixed in a steady speed. The biochemistry reaction of aerobic oxygen microbiology will consume the dissolved oxygen and produce carbon dioxide. According to the gas-liquid two-phase balance principle, the carbon dioxide that inside the air cabinet can be completely absorbed by NaOH. The oxygen in the air of upper incubator will be continuously provided to the microbiology in the water sample, which depressurizes the oxygen in the upper air. Measure the decrease of the oxygen pressure by differential pressure meter. The result is the Biochemical oxygen demand in the determined period.

1、Get the BOD not by the means of Iodimetry; observe the Variation Rule of BOD instantaneously in five days or twenty days and draw the variation curve of BOD5 or BOD20;
2、Ordinary sample (such as sewage, water in river and lake, and industry waste water) with BOD under 1000mg/L needn’t be diluted.
3、The tested values got in several times can be added up so as to avoid the mistake of exceeding the Measuring range made by wrong estimation of the BOD of water sample. Special leak-proof design can ensure that the measuring system is completely sealed, which improves the delicacy of the test, extends the life span of incubator, and guarantees the accuracy and liability of the test results.
The instrument can be used in environment protection, water source management, water quality supervision, biochemistry test, hygiene and anti-epidemic, medicine industry, food and light industry, Petrol Chemical Industry, water use in urban, sewage process and all water quality management departments and corporations.
Test Scale ：It needs to be diluted if the titer is over 1000mg/L.
Test Precision ：Test glucose-glutamic liquid, the BOD5 of which is 200mg/L, and the result is within the range of 180~230mg/L;