Studies On The Treatment Of Dye-wastewater With Three-Dimensional Electrode Reactor

In this paper, the influence factors and reaction mechanism of using three-dimensional electrode treated dye-wastewater with acid scarlet 3R as a modelpollutant were researched. In order to provide the optimal results for industrialapplication, the favorable parameters were discussed.The effects of material of plate and filling element, cell voltage, current density,original solution concentration, electrolysis time, electrolyte, pH value and insulationon the removal efficiency were inspected to decide optimal experiment conditions.The relation between Oxidation Reduction Potentia(lORP)and removal state wasstudied. The experimental results indicated that ORP and COD present hypotaxis ofpositive correlativity, ORP reflect the removal effect in a way, what extent the reactioncarry on can be deduced by the decreased degree of ORP. In addition, current value inreaction process was help to deduce pollutant removal state. The current value afterremoval effect going to stable was correlative to pollutant concentration.The removal effects of different locations in the reactor were not same. Theremoval rates in the directions vertical to plate and parallel to plate were all high atboth sides, low in the center. This was attributed to the different degree of activecarbon particles being duplicate polarized and other factors.The reaction mechanism of three-dimensional electrode was researched. Thecolorimetry method was used to determine hydroxyl free radical in the process ofelectrolysis. The experimental results indicated that the active hydroxyl free radicalexists in three-dimensional electrode system. In virtue of Ultraviolet-visible spectrum,the decomposed offspring of acid scarlet 3R dye is analysed. The results indicated thatthe main reason of acid scarlet 3R decoloring is the break of azo bonds.Three-dimensional electrode reactor had good effect to monoazo dye, diazo dye,trisazo dye, triarylmethane dye, anthraquinone dye. There were small granules in theeffluent of acid scarlet 3R dye-wastewater after three-dimensional electrode reactortreating. These small granules could effectively filtrated by winding filtering element,thus the removal effect was further improved.