| Through investigating and studying the production process of velvet fabric and corduroy fabric from Chengpeng printing and dyeing factory, this article reviewed the running actuality of primary wastewater treatment system on the base of masterying the quality characteristics of wastewater. Meanwhile, according to the requirements specified in the Discharge Standard of Water Pollutants for Dyeing and Finishing of Textile Industry in Jiangsu province, the combined process of hydrolytic acidification+secondary contact oxidation+sand filtration was advanced. Because the secondary bio-chemistry treatment process had been mature now, this article primarily studied the advanced treatment for velvet fabric and corduroy fabric printing and dyeing wastewater.This article planned to use the aerated bio-carbon filtration or aerated bio-ceramic filter to treat the velvet fabric and corduroy fabric printing and dyeing wastewater. Through analyzing the technical characteristics, operation principle, influencing factors of both processes, the influence of pollutant removal effect by gas-water ratio, hydraulic load, filter layer height and relevant back-flush way, gas-water intensity and running period was studied. By comparing, the aerated bio-carbon filter was used as the final process of the advanced treatment.The main conclusions of this study were listed as follows:(1) The effect of using fast start-up method of aerobic precoating during the process of secondary bio-chemistry treatment was Well. By running of biofilm growing for 36days, when the influent CODCr of hydrolytic acidification - secondary contact oxidation process ranged from 486mg/L to 629mg/L under the temperature of 14-18℃, the effluent CODCr stabilized between 90 mg/L and 100mg/L, which reached the requirement of subsequent advanced treatment, and the removal ratio of CODCr maintained above 80%.(2) The experiment of biofilm growing by inoculation of advanced treatment showed that when the conditions of gas-water ratio, HRT, water temperature and pH were 3:1, 1-2h, 15.6-21.6℃and 7.2-7.5 respectively, the removal ratio of NH3-N reached above 60% while aerated bio-carbon filter was running continuously for 15 days and 16 days of aerated bio-ceramic filter, then the biofilm growing finished successfully.(3) By comparing and analyzing the experimental results of aerated bio-carbon filter and aerated bio-ceramic filter, it showed that the removal effect for CODCr, NH3-N and turbidity of velvet and corduroy fabric textile wastewater were both well. Though the cost of aerated bio-ceramic filter was lower, the effluent color could not meet the requirement. So the aerated bio-carbon filter was adopted as the final advanced treatment process.(4) On the base of experimental results and theoretical analysis, the design and working parameters of aerated bio-carbon filter were listed as follows: gas-water ratio (3.5:1), hydraulic load (0.5m3/(m2.s)), HRT(1.6h), carbon layer height (90cm), running period (4-5 days). When the removal ratio of SS was below 80%, the operation of back-flush was taken. The mode of back-flush was air purge—air-water back-flush—water rinse. The air intensity and time of separate air purge phase were 8.5L/(m2.s) and 3min, while the air and water intensity were 8L/(m2.s) and 2L/(m2.s), the time was 5.5min in the phase of air-water back-flush, and water intensity and time were 7L/(m2.s) and 5min in the phase of separate water rinse.(5) Under above conditions, the advanced treatment effluent could reach the requirements of ((The reuse of urban recycling water—Water quality standard for urban miscellaneous water consumption)) to be reused for lavatory flushing road clearing and virescence etc. So original water of 165m3 could be saved everyday as well as water rate of 140 thousand yuan every year, and the pollutants of COD, BOD SS and NH3-N which were let into the environment could be decreased by 22 tons, 6tons, 20.4 tons and 5.1 tons respectively, and the economic benefit and environmental benefit were created well.
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