Papers by Keyword: Internal Electrolysis

Abstract: Aiming at the difficulty of treating dyeing wastewater, the limitation of the traditional electrolysis method, the high cost of active carbon and the environmental pollution of the chicken manure in farms, the paper put forward a new method of using iron combined with biological carbon derived from chicken manure forming internal electrolysis to treat dyeing wastewater. It discussed the effects of mass ratio of iron and biological carbon derived from chicken manure, pH, reaction time, the particle size of iron filings, the aeration rate, circulation velocity and the circling liquid volume on the removal rate of the organic matter in wastewater. The result showed that iron combined with biological carbon derived from chicken manure forming internal electrolysis to treat dyeing wastewater could "using waste to treat waste" and the effect was better. The removal rate of COD was over 85% and the decolorization rate was over 95% when the mass ratio of iron and biological carbon derived from chicken manure was 1:1, the PH was 6, reaction time was was 60min, the particle size of iron filings was 0.9~2.0mm, the aeration rate was 10mL/min, circulation velocity was 50r/min and the circling liquid volume was 2000mL.

Abstract: In this study, Fe/C internal electrolysis was used to pretreat the wastewater of lead 2, 4, 6-trinitroresorcinate (LTNR) production. The influences of pH, acids, reaction time and Fe/C volume ratio on COD removal were investigated. The optimum condition of iron-carbon electrolysis was determined by orthogonal experiment. And the reaction kinetics of COD removal and mechanism of contaminant removal were preliminary explored. The results showed that wastewater pH adjusted by sulfuric acid was more economical and better for COD removal. The effect of pH is the greatest. Two processes programs (pH3, Fe/C volume ratio 1.0, reaction time 24hr; pH3, Fe/C volume ratio 1.2, reaction time 18hr) are advised in project. Under the two process conditions, COD removal rates are 73.78% and 72.42%, respectively. The COD removal could be well described by pseudo-second-order kinetic model, and the reaction rate constant is 2.804×10^-4 L/(mg·hr). Within the range of 0-24hr, film diffusion is the rate controlling step of the electrolysis process. The degradation process of trinitroresorcinate may be as follow: trinitroresorcinate→nitroaniline phenol or phenol aniline →nitrobenzene quinone or benzoquinone and ammonia→biodegradable or inorganics and nitrate.

Abstract: Treatment of nitrobenzene-containing wastewater was carried out by iron-carbon internal electrolysis and microwave and its degradation mechanism was investigated. The parameters is found in the process of treating nitrobenzene-containing wastewater. The experimental results showed that the microwave intensified the internal electrolysis effect of iron-carbon and the existence of iron was beneficial to the regeneration of activated carbon. Under the optimized electrolysis conditions as follows: iron dosage was 175g, molar ratio of Fe to C was 3, pH was 3, microwave power was 640W, irradiation time was 4 min and aeration amount was 2.5L/min, the removal rates of CODcr, chroma and turbidity were 94.7 %, 95.6 % and 90.3 %, respectively.

Abstract: The printing and dyeing wastewater was treated by internal electrolysis method. The results show the chromaticity removal rate was up to 98.53 percent and COD removal rate 85.98 percent under the optimum conditions of wastewater pH 4, reaction time 30 minutes, the electric conductivity 1450μm/cm, the value BOD5/COD increases from 0.34 to 0.51. Moreover, the pH, Fe2+ concentration and absorbance of wastewater changed in the process, the mechanism of that was also analyzed.

Abstract: Due to increasing water scarcity, appropriate technologies were need for advanced treatment of wastewater to enable reuse. Effect of iron-carbon internal electrolysis in tertiary treatment of wastewater was investigated in this study. Static experiment was adopted to evaluate influence of Fe/C ratio, pH, reaction time and aeration on pollutant removal by iron-carbon internal electrolysis. Then dynamic experiment was conducted to determine removal rate of CODcr, TP, chroma and NO₃^--N. The results showed that internal electrolysis could remove COD_cr, TP and chroma efficiently. The optimal ratio of Fe/C was 1:1. Initial pH could affect removal efficiency. In acid circumstance, the removal rate was higher. Degradation reaction by internal electrolysis was fast. when the reaction time was 10min, the removal rate could be ideal. In the process of internal electrolysis, aeration could increase pollutant removal rate. In aerated system, when the reaction time was only 15min, removal rate of COD_cr, TP and chroma could reach 49.2%, 89% and 75%. But in non-aerated system, only when the reaction time was 100min could removal rate of these indexes reach 46.5%, 81% and 85.1%. In dynamic experiment, removal rate of COD_cr, TP, chroma and NO₃- could reach above 40%, 90%, 75% and 20%, respectively.