Study On Combined Electro-catalyze Oxidation And Biological Treatment Of Dyestuff Wastewater

Production wastewater of dyestuff industry has been one of the mainwater body's pollution source currently. Because of its great quantity ofwater, high chromaticity color, complicated composition, strong toxicity,low degradability (BOD/COD_cr is low), unstable pH value, erraticcomponent, dye manufacturing wastewater is one of the difficulty inwastewater processing recently. Aimed at the character of dyemanufacturing wastewater, this experiment use electro-catalyze oxidationmethod to change the molecule structure of the dyestuffs. The influenceof pH value, the kind and the concentration of electrolyte, the voltagehave been studied in the research, the optimal disposal parameter of thedegradation process has been chosen. The article also studies theanthraquinone's biodegradability in the aerobic and anaerobic condition.Three processes to deal with dye manufacturing wastewater are compared:aerobic, anaerobic-aerobic and electrocatalyze-aerobic. The conclusionsare as follow:1. Taken into consideration the electric current efficiency and energyefficiency, the optimal condition has been chosen: the groove voltage is10V, the initial pH value is 4, the concentration of NaCl is 2.0g/L. After50min's electrolyse, COD removal rate can reach 61.46ï¼…, the colorremoval rate can get 83.14ï¼…. Impulse electric current can enhance theelectric current efficiency.2. Using Warburg respirometer to determine the biochemicalrespiratory line, and compare with endogenous respiratory line, thedegradation function can be estimated directly. Anthraquinone dye stuff'sbiochemical respiratory line is not far from the endogenous respiratory line, so it is biodegradable, but non-degradable. However, thebiochemical respiratory line of the electro-catalyze oxidized wastewaterare all above the endogenous respiratory line. This shows that the processof electrochemistry playing an important part in removing thechromaticity color and increasing the degradability.3. Compared with aerobic process and anaerobic-aerobic process,electrocatalyze oxidation-aerobic process's color removal rate and CODremoval rate is the greatest. Using aerobic process to treat theelectro-catalyze oxidized wastewater, after 24h's aerating, COD can fallto 220mg/L, the chromaticity color can descend to 25. This resultconforms to the conclusion that the biodegradability of the wastewaterhas been increased.