Investigation On The Deep Treatment Of Pulping Effluent By New Iron-carbon Micro-electrolysis And Fenton Combined Process

In this paper,the regularization of iron-carbon micro-electrolytic fillers were made through the optimization of the prepared condition and used iron powder,activated carbon and clay as the main component,adding a small amount of additive material which was easily decomposed under high-temperature.And then the fillers were applied to the pulping wastewater to obtain the best treatment condition and effects by studying the key influencing factors in the application process.Finally,the deep treatment of pulping effluent by new iron-carbon micro-electrolysis and Fenton combined process to achieve high efficiency and low cost discharge.The results show that the optimum prepared condition for the regularization of iron-carbon micro-electrolytic fillers were: the mass ratio of Fe-C was 1:1,the mass fraction of clay was 25%,the addition of ammonium chloride was 0.5%,calcined for 2h at 400?.The regularization of iron-carbon filler still can use the difference potential between Fe and C to form a small original battery,played an electrolysis.It had a good effect and had not appeared the phenomenon of ditch flow,compaction and loss of active components during treatment the pulp wastewater and p-chlorophenol simulated wastewater.The optimal treatment process of the regularization of iron-carbon micro-electrolytic fillers were: with the pH value was 2.5,the addition amount of Fe-C fillers were 90 g/L,the aeration flow rate was 0.3 m3/h,and at the 25²7? reacted 90 min,the removal rate of CODCr and TOC can reach 69.88% and 70.75%.Used the removal rate of CODCr and TOC as the response value,designed and analyzed experiment by using Design-Expert analysis software,to obtain the optimal treatment conditions were as follows: The initial pH of the reaction was 2.37,the amount of fillers was 32.67 g/L and the reaction time was 92.49 min,the removal rate of CODCr can reach 69.23% under the aeration flow rate of 0.3 m3/h and the 25²7?.The experimental results show that the relative error is only 0.83% and the model predictive value is accurate and reliable.The results of microelectrolysis and Fenton oxidation showed that: When the H₂O₂ was added at the beginning of the microelectrolysis reaction,the reaction system can be formed a microelectrolysis-Fenton oxidation coupling process,which adding H₂O₂ 0.8 ml/L,and after 75 min reaction,the total CODCr and TOC removal rate could reach to 85.98% and 89.61% respectively.Which were higher than those of the micro-electrolytic alone treatment for 16.10% and 18.86%.However,to compare with the micro-electrolysis-Fenton oxidation combined treatment process,it could save a special Fenton oxidation reactor and greatly shorten the depth of treatment time,to achieve a high efficiency and low cost of discharge.The fillers which adding ammonium chloride and wastewater before and after the reaction showed that the addition of ammonium chloride could clear the internal pores of the filler by the decomposition of the gas.After the reaction,the iron powder was partially dissolved,but the basic skeleton remained good.The micro-electrolytic and Fenton oxidation coupling process had a better removal effect to the conjugate double bonds and the carbonyl group,and had a good removal or conversion capacity for the aromatic organics,which also can significantly reduce the species and relative contents of organic pollutants,and improve the quality of the effluent.