【作者】 姚曙光；

【导师】 杨玉杰；

【作者基本信息】 华侨大学 ， 化学工程， 2007， 硕士

【摘要】 综述了印染废水的现状及印染废水深度处理技术研究进展,并简要介绍了CASS(Cyclic Activated Sludge System)工艺特点、工作原理及应用。本文选用CASS作为其深度处理漂染废水的试验工艺,并对CASS动力学数学模型进行了简要探讨。主要研究结论如下:1、试验研究表明,在水力停留时间HRT=15.5h下CASS系统处理效果最好,污泥浓度为1071mg/L,COD污泥负荷为0.21kgCOD/(kgMLSS·d),进水COD浓度为112~194mg/L,出水COD浓度49.0~58.7mg/L,去除率在52.5%~70.8%之间,平均去除率62.1%,出水COD浓度波动很小,稳定在60mg/L以下。2、在不同进水浓度下,COD去除率,随反应时间的变化,其趋势是稳定的,说明CASS系统抗冲击负荷特别显著。另外,在CASS系统中,通过调整回流比,可以有效的控制出水水质。进水时间长短对CASS反应器中有机物降解过程有比较大的影响。进水时间越长,有机物投加的速度越慢,越有利于难降解有机物的去除;另一方面,长时间进水有利于生物选择器絮凝性细菌的生成及保证缺氧区的水解、酸化效果。3、对主反应区基质降解动力学特征进行研究表明,试验废水基质降解速率服从一级反应动力学关系,曝气5个小时后,废水中的可溶性有机物已基本降解完全,有机物降解进入了难降解阶段。COD可生化率仅有60.7,说明该废水的可生化性不高,这也说明CASS缺氧水解酸化的必要性及生化出水尝试物化处理的可行性。4、物化实验表明,混凝剂聚合氯化铝对COD的去除效果优于硫酸铝,最佳剂量在100mg/L左右,去除率在20%左右,物化去除率不高。同时实验发现,无论是硫酸铝还是聚合氯化铝对色度改观并不大。5、漂染废水二级处理出水经CASS深度处理后,出水中仍含有极少量的染料,使其带有一定的色度,呈浅黄色。另外一些无机盐如Na2SO4、NaCl无法通过CASS生化深度处理去除,可回用于对用水要求相对较低的工序,如煮练和漂洗工序,即可减少生产用水,又可减少废水排放,对漂染企业来讲是切实可行的。6、本课题来源于漂染废水二级出水的实际工程,针对性强。从COD去除率、脱色效果、达标可靠性、对水质水量适应性、投资、运行费用、管理等方面综合考虑,CASS工艺作为漂染废水深度处理技术是切实可行的好方法,其效果优于其它方法,费用省于其它方法。CASS工艺对于现有漂染废水处理设施的改造及回用有着很好的应用前景。7、本文对CASS动力学模型进行了探讨,对动力学参数进行了估计,并用Matlab程序对数学模型进行了求解。在印染废水深度处理中对CASS反应器进行模拟,优化设计参数,从而应用于工程设计。更多还原

【Abstract】 The present situation and the study progress on advance treatment of the dyeing wastewater is rerviewed, and the characteristics, principles and applications of Cyclic Activated Sludge System (CASS) briefly introduced. The experiment eploys the technique of CASS to further treat the bleaching and dyeing wastewater, and establishes the corresponding dynamics mathematics model. The main results are summarized as follows:1. The experiment indicated that the CASS’s treating effect is the best when HRT is 15.5h, MLSS 1071mg/L, COD Sludge load 0.21 kgCOD/(kgMLSS·d), the influent COD 112~194mg/L, with the effluent COD being 49.0~58.7mg/L, removal rate between 52.5% and 70.8% steadily, average removal rate 62.12%, and effluent COD below 60mg/L.2. Under various influent concentration of wastewater,the COD removal rate kept stable, along with the reaction time, which proved the CASS system anti-impact load is specially remarkable. Moreover, the quality of water can be effectively controlled via adjusting reflux ratio of sludge. It was found the influent time played key role to the quality of effluent water. The longer the influent time, the slower the organism being added, the better the removal effect of unsoluable organim.Further more, the long influent time contribute to the formation of flocculence bacterium in the biological selector and the hydrolyzition and acidification of the organism in the anoxic zone.3. The experiment results showed that the degradation velocity obeys one class reaction kinetics. After 5 hours’aeration, soluble organic compound degraded almost completely, and organic compound difficultly to degrade remained. COD biodegradation rate only 60.7, which manifested that the necessity of hydrolyzation and acidification, and the feasibility of chemical-physical method for the effluent of CASS.4. The COD removal effect of poly-aluminum chloride coagulant surpasses that of the aluminium sulfate.With best dosage about 100 mg/L, removal rate is about 20%, not significant. However, both of the two coagulants display little influence on the wastewater chromaticity. 5. After the secondary effluent of bleaching and dyeing wastewater treated by CASS, it still contained a few dyes which enable it to have certain chromaticity of buff color. Moreover some inorganic salt like Na2SO4, NaCl are unable to be removaled. Therefore, the effluent water was only fit to be reused in such working procedure like boil practices and rinse with relatively low water quality request, which would not only reduce the production water supply, but also may reduce the wastewater emissions. Thus the technique of CAAS is practical and feasible for dyeing factories.6. This experiment aimed to serve the practical treatment to secondary effluent of bleaching and dyeing wastewater. In terms of COD removal rate, color removal effect, reliability, water quality, the investment, the operation expense, and the management etc., CASS is a quite practical and feasible wastewater treating method, which is superior to other means. Therefore, CASS technique has promising application prospect.7. This article has carried on the discussion to dynamics model of CASS, estimated dynamics parameters, caculated the mathematical model with Matlab to optimum the design parameters, which is important to the practical application of CASS in treating the dying wastewater.更多还原