Study Of Detecting Dissolved Oxygen And Sensing Technology

Molecular oxygen in the air dissolved in water is called dissolvedoxygen (DO), its value is not only one of the indicators in water qualitymonitoring of the environmental protection department but also animportant condition of the self-purification capacity of the water.Detecting the dissolved oxygen content accurately, conveniently andrapidly is of great importance for environmental monitoring, industrialand agricultural production.On the basis of analyzing the fundamental principles of dissolvedoxygen detection, we independently designed and developed atwo-electrode polarographic dissolved oxygen sensor especiallyintroduced the production process. While analyzing the material of theelectrodes, we studied the surface area of the test electrode, the materialpurity of the auxiliary electrode and their influences on the performancesof the sensor through the experiments. We also introduced the selection oftemperature electrode and the design of the sensor cavity, verified thestability of the sensor in both saturated oxygen and zero-oxygenconditions and introduced the hardware circuit and the software design of the system. The instrument is calibrated using the HK-258portable tracedissolved oxygen analyzer of Beijing Huakeyi Power Plant InstrumentResearch Institute. We hope it can be widely used in water treatment ofthe food and beverage industry, the semiconductor manufacturingindustry, pharmaceutical industry as well as in the measurement of boilerfeed water in power plants.