Measurement Of Trace Heacy Metals In Seawater System

With the development of China’s coastal economies and technological progress,pollution of partial coastal waters are gradually increasing. Heavy metal pollution, asan important indicator of marine pollution, is more and more noticeable. Soluble heavymetals will cause death, retardants and other toxic and teratogenic effects on marineorganisms through bioaccumulation effect, and ultimately do harm to human health viathe food chain. Therefore, the development of a fast automatic measurement systemthat measures heavy metals has a certain practical significance. This paper introducesthe research progress on seawater heavy metal detection technology in recent years,aiming at the soluble state trace heavy metal cadmium (Cd2+), copper (Cu2+), zinc(Zn2+) and nickel (Ni2+), which is heavy polluting and high content in waters, a methodcombining spectrophotometry and flow injection analysis was proposed to measuretrace amount of soluble heavy metals in seawater. The main contents include:Firstly, the background and the significance of the research, the methods andcurrent research status on detecting trace amounts of heavy metals in seawater wereintroduced. The advantages and disadvantages of several traditional methods for themeasurement of heavy metal were analyzed; the research contents and innovation ofthis article were proposed.Secondly, the theory of spectrophotometry and flow injection analysis methodwere introduced. The chromogenic reaction were carried out through the theory ofspectrophotometry and the visible absorption spectra between550nm and800nm ofthe four heavy metals ions Cd2+, Cu2+, Zn2+, Ni2+after the chromogenic reaction wereanalysed. The optimal measurement wavelength was obtained via the analysis of theabsorption spectra.Again, consider the impact of heavy metals in the water measured by the factorsdetermined PH value, temperature, time, the impact of salinity on the absorbance ofthe respective heavy metal ions in the575nm,605nm,620nm and650nm wavelengthslinearity and sensitivity of the analysis under, then established a four-level orthogonal correction factors as set four algorithms modeled data sets, the algorithm modelingmulti-component measurement using the method, by analyzing and comparing thethree main modeling approach, the final selection algorithm built PLS algorithm mold,draw a mathematical model and error model analysis.Finally, the trace heavy metal measurement system was set up according to thebuilt mathematical model. The device selection on all parts of the system was carriedout, and the water flow section, the light path section and the circuit section weredesigned. The hardware and software of the system was completed and the systemperformance was tested.