Discussion On Determination Method Of Sulfide In Water And Wastewater

Sulfide is one of the important factors to express water body quality. As influenced by the different water body pollution degree, it's very difficult to determine it accurately. Pretreatment is the key link. This article studies characteristics of sulfides in water and wastewater, so as to determine accurately, simply and fast.The determination of sulfide has the national standard methods, also has recommendation methods. On the base of massive experiments, this article studied and discussed the characteristic and application scope of different determination methods, summarized the quality assurance measures. As to non-standard methods, designed experiment plan according to experience and material first, then did lots of concrete experiments, confirmed its serviceability simultaneously, finally obtained the conclusions have practical guiding sense through discussion on the result .In the iodine method, many factors easy to neglect had all carried on discussion, proposed the standard operation technology principle, which improved the accuracy and precision; the article proposed the improvement method of pretreatment, confirmed its recycling effect. In the spectrophotometric method, carrying on sample pretreatment with the arseniuretted hydrogen occurrence-absorption installment, equated with GB/T16489-1996, was operated simply and fast. Applied this equipment in the test of methylene blue spectrophotometric method, confirmed its recycling effect, the best analysis conditions were selected, and how to remove interference was deeply studied; Trace S2- in sewage was determined indirectly by atomic absorption spectrometry method, the recycling rate could reach at 93%-94.7% in actual sample determination; This article also thoroughly studied and analyzed the UV spectrophotometric method, after experimented certain factors effected the determination, the best test condition was proposed. The detection limit was 0.04mg/L, relative standard deviation was 1.4%, and the recovery rate was 91.6%-102% ; A spectrofluorimetric determination of trace amounts of sulfide was confirmed. The test indicated that, the acidified - air flush could eliminate the influence of coexistence ions, the main advantages, apart from the extremely high sensitivity of the method, good stability and reproduction quality displayed simultaneously.