Design Of The Rapid Detection Instrument Of Heavy Metal Ions

Even the heavy metal pollution was produced the water environment was extremelydifficult to repair itself. When the heavy metal ions enter the body it seriously endangeredthe lives and safety of human which has a direct effect on the nervous system, internalorgans and other important parts. Therefore, prevention of heavy metal pollution wasimperative and the important part is detection of heavy metal ions and itsconcentration.Currently domestic testing technology was not mature. Foreign equipmentwas expensive and often a single instrument can only detect one ion. The rapid detectioninstrument of heavy metal ions was designed.Through the development of rapid detection of heavy metal ions some problems wassolved:1) A quick and effective detection method was found based on electrochemicaltechniques and large number of experiments. We can get the ion type and concentration byobserving the curves.2) A dedicated volt-ampere electrode system was selected byexperimental comparison. It speeds up the detection speed, improved sensitivity, andavoid the use of mercury electrodes produce secondary pollution.3) In order to meet theneeds of the measurement process a multi-channel transformation valve which suitablelow-viscosity fluids was developed (8path). A multi-channel transformation valve wasused for a kind of water quality testing equipment. Under the convenient controlling, itselected a path through the multi-channel liquid channels and the only export. It can selectdifferent liquid injection detection device to detect according to demands.4) A controlsystem based on MCU had been independently developed. Including: Constant PotentialDevice,31-bits compound AD converter, load cell circuit which can accurate weighvariety of liquids and so on. They significantly improve the measurement accuracy of thesystem. The31-bits compound AD converter was constituted of the relay, D/A converterand A/D converter. It implements the31-bit A/D converter. The equivalent of each wordreached0.93pA and it solved the very weak signal measurement problems in themeasuring range of2mA.Additionally, PC display program was designed to achieve thecommunication between MCU control systems and computer serial. It improvedinteractive features and achieved a heavy metal ion concentration detection data display,preservation and other functions.It used a variety of metal ions had different response in the excitation of differentamplitude of pulse voltage signal and can quickly detect the concentration of heavy metal ions of water. It has detection speed, good accuracy, high sensitivity, long electrode lifeand it can simultaneously detect copper, zinc, lead, cadmium, mercury and other heavymetal ions.