Treatment Of Plating Wastewater With Heavy Metal Ions By Micro-eletrolysis And Biofilm Process

The plating wastewater with cyanide, acid, alkali and heavy metal ions such as chromium, copper, nickel, zinc, cadmium etc. has appeared to be environmental serious damage despite its small quantity proportion in all through the industrial wastewater. For the moment, the research and application of the wastewater treatment has commenced forwardly in domestic and overseas. In this paper, a novel micro-electro-biofilm complex technology to dispose industrial plating wastewater was adopted based on its advantage of micro-electrolysis and biofilm adsorption and experiment data already be done by the same technology. First, the mixed bacteria were cultivated, domesticated and then put into biofilm training device. To observe the surface configuration and internal structure of cultivated and domesticated bacteria, the SEM and TEM analysis have been carried out. Meanwhile the growth curve measure has been done and applying the counting bacterium process to compare the bacteric quantity of cultivated and domesticated period. In the experiment of analyzing single electrolysis and biofilm process, selecting such plate as electrode material that has the high removal rate, and different electrode coupling manner was also taken into account. By determining the adsorption isotherm of different concentration, the steady adsorptive time and optimal concentration have been confirmed. In the experiment, the test of adsorptive factors such as temperature, pH and biomass was carried out to find out the optimal adsorptive condition. Comparisons of interim and continuous operation, circular complex process and single biofilm process have been analyzed in combined process. The intention is to decide the better treatment operation, and the discussion of the optimal circular wastewater quantity under different electrode material and whether the complex process needs faint electric domestication and accession of nutrition component in the experimental process was separately described in the paper. At last, the adsorptive isotherm and kinetic models of single, binary component in static adsorptive experiment were studied. The results show that the single component (Cr6+ and Zn2+) and binary components adsorptive system according with Langmuir equation very well. Owning to lack of abundant data home and overseas, in the given concentration range, the correlative coefficients of the four kinetic models display the small difference, so searching for the new kinetic equations to serve the actual adsorptive course needs more attention.