Study On The Degradation Of Landfill Leachate By The Three-dimensional Electrodes–one-piece Fe-C Micro-electrolysis

Solid wastes’ sanitary landfill has been widely used in China for the past fewyears with the advantages of large handling capacity, simple processing, instant effectand mature technology and so on. However, due to the moisture from precipitationand inside the solid waste itself, the landfill will inevitably produce large amounts ofpercolates during use, which possess the characteristics of serious pollution, highammonia, high organic content, complex composition, poor biodegradability anddifficult subsequent treatment and so on. It will make a terrible effect on groundwaterand urban sewage systems if not handled properly.The experiment mentioned in this paper has, combining with electrodeelectrolysis and Fe-C micro electrolysis, constructed three-dimensional electrodes–one-piece Fe-C micro-electrolysis reactor,which degrades pollutants by electrodeoxidation and increases substantially the space-time effects of the reactor by addingthe Fe-C micro-electrolysis filler at the same time. Basing on the experimental studyof three-dimensional electrodes——one-piece Fe/C micro-electrolysis reactor, itsoptimal reaction factors and conditions areconfirmed and the packing characteristics,three-dimensional fluorescence spectral characteristics in and out of the water and thedynamic characteristics of the reactor has been analyzed simultaneously.The reactor uses graphite and stainless steel as electrodes and a sort ofpre-sintering Fe/C micro-electrolysis filler for the third electrode. Water applied in thetest, being the clarifier effluent during the processing of a landfill site, figures out thata reactor is suitable to work under the acidic conditions and residence time andcurrent density has a great influence on the reactor effluent by exploring residencetime, current density, influent pH and water influent concentration of chloride ionsand other parameters of the reactor; All the reaction efficiencies of one-piece reactorare higher than that of single electrode electrolysis and Fe/C micro-electrolysis by aseparate process control experiment. Meanwhile, according to the comparative studyof the filler, about2%performance degradation occurs after a certain degree ofdepletion and filler can be added simply within the limited decrease. Finally, four factors and four levels of orthogonal experiment have been designed by theorthogonal experimental design method. The result of the analysis concludes that, thereactor works best under the conditions of8hours residence time,12mA/cm2currentdensity, the influent pH to4and chloride ion concentration on the corrosion of3000mg/L, at this moment ammonia removal efficiency is42.3%, TOC removal rate70.6%and total phosphorus removal96.1%. Carrying out kinetics fitting for thenitrogen, phosphorus and organic matter removal of one-piece reactor with factors ofreaction time and influent concentration, organic matter removal process and nitrogenremoval process four hours later conform to one stage reaction kinetics whilephosphorus removal process accords with second-order reaction kinetics. Dynamicmodel can be used to forecast and analyze effluent quality of the reactor.Based on three-dimensional fluorescence spectroscopy (3DEEM) analysis to thewater quality, One-piece reactor plays a significant role in the concentration andingredient of the soluble organic matter (DOM) in sewage.It is more likely to bedisassembled by microorganism if protein-like substances increase in sewage. Intheory, it improves biodegradability of the sewage.