| The research of the high concentration chemical industry wastewater treatment technology was always considered being a hot and difficult field. On the base of summing up physics and chemistry pretreatment technology comprehensively, this paper considered that micro-electrolysis technology which conclude electrochemistry, oxide deoxidation and flocculation action can be used for low pH, high acidity, high concentration chemical industry organic wastewater pretreatment conveniently. In this paper, the produces wastewater of a fine chemical enterprise which subordinated TH-UNIS company was the treating research wastewater sample. This study included three parts: lab-research, engineering design and engineering debugging research. The laboratory studies included the influences of the inside system of Fe/C reactor upon the treatment efficiency, such as the iron species, Fe/C ratio; and the influences of operation parameters of Fe/C micro-electrolysis reactor, such as HRT, wastewater pH, aeration amounts and so on. This paper concluded that:①The both-aeration system, which was aerated in Fe/C micro-electrolysis reactor and coagulation reactor, could get the optimum COD removal result. Especially the aeration in Fe/C micro-electrolysis reactor, the air rotating could prevent the blocking up and harden of Fe/C bed, and also could prevent short-flow.②If the reaction time was not a restrictive factor, the affection of iron species to COD removal ability was not notable. But because of the more Fe3C content in cast iron, more micro-cells would be formed, that gained faster reacting rate and less reacting time. As to this Fe/C micro-electrolysis system, the reacting time of cast iron system was 2hr, and that of iron paring system was 5hr. So, cast iron suggested to be the prior material for Fe/C micro-electrolysis reactor.③From the research, Fe/C ratio affected the treatment efficiency. And the optimum Fe/C cubage-ratio was 3:4～4:3.④Based on the results of tests, this paper fitted the time-curves and time-equations of COD removal with Origin7.0 soft. Through the primary dynamics analysis, found that the COD removal process in Fe/C aeration micro-electrolysis system was through three phases. First phase, it was the acidic dissolution phase of Fe, and the COD removal by air-taking-off phase, and the low-velocity phase of micro-electrolysis, in this phase, the dissolution velocity of Fe was up to 358 mg TFe/min. Second phase was the high velocity phase of micro-electrolysis, in this phase, about 60% of COD that being removed in all process was transformed. Third phase was the stagnation phase of micro-electrolysis, all reactions have been balanced, and the COD removal has been stopped.⑤In the laboratory conditions, the optimum control parameters of aerating coagulation were: pH≈9.0, aeration time≈35min, anion PAM dosage≈2mg/L. Here, there would be the least sludge volume and the highest COD removal rate. After coagulating sedimentation, the phosphate concentration was lower than 2mg/L.⑥In the continuum tests, the affection of some functional parameters to Fe/C micro-electrolysis system has been considered. Found that, pH was the key factor to decide the COD removal rate, and air quantity and HRT was the inferior factor. If at the conditions of pH≈3, HRT≈3h, air/water ratio≈200, it could get the optimum treatment result, the COD removal rate would reach 52.6%. At the optimum control parameters, the bio-degradability of wastewater could enhance great, BOD5/COD ratio was up to 0.34 from 0.22, and SOUR was up to 29.38 g/kgVSS·h from 16.67 g/kgVSS·h. Depend on the micro-electrolysis and air-taking-off, the TN removal rare could reach above 50%.⑦Based on the lab-researches, referenced other engineering practices design parameters, considered some safety factors, the Fe/C micro-electrolysis system has been designed. In this design, in order to prevent the blocking up and harden of Fe/C bed, some methods have been adopted, such as air flushing-back system, and the layer-lattice structure of Fe/C bed. Through the engineering debugging, this paper summed up the experience and edifyingness, put forward some advices, so that to promote the engineering application of Fe/C micro-electrolysis technology.
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