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91.
电解法处理活性染料废水的研究   总被引:9,自引:0,他引:9  
某化工厂活性染料生产废水高CODCr值、高浓度、高色度、高盐分、成分复杂、有毒有害物质多、可生化性差。实验确定了废水经AS剂絮凝和电解预处理的研究方案。主要考察了电极极板材料、电解pH值、电解电压大小、电解时间和电极极板间距对CODCr去除效果的影响 ,从而确定了最佳电解条件 :采用石墨板电极 ,pH =3,电解电压 6 5V ,电解时间 5 0min ,电极极板间距 5cm。最佳条件下经放大实验 ,发现CODCr去除率高达 70 %以上。  相似文献   
92.
By increasing particle concentration and G value (root-mean-square velocity gradient) to enhance flocculation, a novel vertical-flow settler was designed to increase sedimentation effectiveness, and to simultaneously improve operational stabilization. Due to the gradual decrease in upward flow-rate of raw water, a floes blanket would form and suspend in the middle section of the settler, not at the bottom as in a conventional clarifier. Enough large floes, resulted from flocculation or fltration, would continuously settle out of the floes blanket, and simultaneously, the floes in raw water or those forming above the blanket would ceaselessly enter the floes blanket. As a result, the floes concentration in the blanket could keep a dynamic balance. The hydrodynamic shear in the blanket was improved by flow separation, which was induced by the abrupt change in flow channel. Due to the floes blanket and improved hydrodynamic shear, flocculation would be enhanced, which was helpful for removing fine particles in raw water. A comparative study showed that the novel vertical-flow settler had a much better performance in the removal of the particles in raw water than a conventional one, when they treated kaolin suspensions of different concentrations (500, 100 and 50 mg/L, respectively) coagulated by polyaluminum chloride(PAC1) at the up-flow rates of 1 and 2 mm/s, respectively.  相似文献   
93.
壳聚糖季铵盐絮凝剂处理丁苯橡胶废水的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
常青  韦俊 《中国环境科学》2012,32(2):232-237
以壳聚糖(CTS)为母体,3-氯-2-羟丙基三甲基氯化铵(CTA)为改性剂,合成了壳聚糖季铵盐阳离子型高分子絮凝剂2-羟丙基三甲基氯化铵壳聚糖(HTCC),以其对高岭土悬浊液的浊度去除率为指标优化合成条件,以HTCC分别与PAC及PAM复配,絮凝处理丁苯橡胶废水.结果表明,最佳合成条件为:质量比MCTS: MCTA: MNaOH =1:2:1.2、反应温度60℃、反应时间3h,在此条件下合成的HTCC对高岭土悬浊液的浊度去除率达96.46%;HTCC+PAC复配在pH6.0~8.0对丁苯橡胶废水的絮凝效果较好,出水余浊<2NTU,色度去除率达92.98%,COD去除率达32.0%;HTCC+PAM复配在pH5.0~8.9对丁苯橡胶废水的絮凝效果最好,余浊<3NTU,COD去除率46.0 %,且投药量小, pH适宜范围宽,优势比较明显.以HTCC与PAC、PAM分别复配处理丁苯橡胶废水可减轻后续生化处理的负荷,降低PAC、PAM的投加量,从而减小出水中残余铝和残余丙烯酰胺单体的含量.  相似文献   
94.
Since the living microorganisms in activated sludge continuously change, it is difficult to conduct controlled experiments and achieve reproducible results for evaluating sludge characteristics. Synthetic sludge, as a chemical surrogate to activated sludge, could be used to investigate the sludge physicochemical properties, and it is desirable to prepare synthetic sludge with similar structure and properties to real activated sludge to explore the flocculation and settlement processes in activated sludge systems. In this work, a high-strength synthetic sludge was prepared with functional polystyrene latex particles as the framework and extracellular polymeric substances (EPS) to modify its surface. The flocculation and settling characteristics of the microspheres and the prepared synthetic sludge were tested. Compared with other three functional polystyrene latex microspheres, the synthetic sludge prepared with EPS-modified polystyrene latex microspheres showed good settling characteristics and a significantly higher strength. They could be used for studying the physicochemical properties of activated sludge.  相似文献   
95.
营养和环境条件对生物絮凝剂合成的影响   总被引:10,自引:1,他引:10  
在考察了红平红球菌Rhodococcus erythropolis CCRC10900基本生长代谢特性的基础上,研究了营养条件对生物絮凝剂合成的影响。R.erythropolis CCRC10909合成的絮凝剂约80%以上分泌至胞外培养基中,仅20%左右的絮凝活性存在于菌体细胞上,蔗糖是该菌生长及絮凝剂合成的最佳碳源;玉米浆既能刺激菌体生长,又能显著提高絮凝剂的水平,生物絮凝剂的合成与培养基碳氮比密切相关,碳氮比在20-30之间时,絮凝活性达到最大,碳氮比低于10或高于100后,絮凝活性迅速下降,提出了促进絮凝剂合成的控制策略,发酵前期适当提高玉米浆的浓度,发酵后期按碳氮比为20-30,补加一定量的蔗糖和尿素,实验结果表明,采用这一策略,最终发酵液的絮凝活性和细胞生长量分别增长了8%和33.3%。  相似文献   
96.
微生物絮凝剂处理含油废水   总被引:2,自引:0,他引:2  
对用一种用发酵法制备的生物絮凝剂的絮凝性能进行了研究。结果表明,试验所得生物絮凝剂具有较好的耐温性和较好的絮凝能力。对试验用乳浊液絮凝除油效率达95%以上,优于商品破乳剂E-3453的絮凝性能。将生物絮凝剂用于含油废水的处理,出水含油量小于5mg/L。  相似文献   
97.
● Medium poly Al salts dominated the PAC residual salts with a rational dosage. ● Settlement flocculation effect under medium poly Al salts showed a better trend. ● Complex of medium poly Al salts and enzymes promoted cell activity. ● Medium poly Al salts were beneficial to the effluent indexes. With the widespread introduction of pre-coagulation prior to the biological unit in various industrial wastewater treatments, it is noteworthy that long-term accumulation of residual coagulants has certains effect on both micro and macro characteristics of activated sludge (AS). In this study, the morphology distributions of residual aluminum salts (RAS) and their effects on the removal efficiency of AS were investigated under different PAC concentrations. The results showed that the dominance of medium polymeric RAS, formed under an appropriate PAC dose of 20 mg/L enhanced the hydrophobicity, flocculation, and sedimentation performances of AS, as well as the enzymatic activity in cells in the sludge system, improving the main pollutants removal efficiency of the treatment system. Comparatively the species composition with monomer and dimer / high polymer RAS as the overwhelming parts under an over-dosed PAC concentration of 55 mg/L resulted in excessive secretion of EPS with loose flocs structure and conspicuous inhibition of cellular activity, leading to the deterioration of physico-chemical and biological properties of AS. Based on these findings, this study can shed light on the role of the RAS hydrolyzed species distributions, closely relevant to Al dosage, in affecting the comprehensive properties of AS and provide a theoretical reference for coagulants dosage precise control in the pretreatment of industrial wastewater.  相似文献   
98.
工业废水中测定六价铬的预处理技术   总被引:4,自引:0,他引:4  
根据复合絮凝剂与阳离子交换树脂两者在分离与处理技术上所起的不同作用 ,提出了将两法联合用作工业废水中测定Cr6 的预处理技术 ,通过一系列条件试验 ,确定最佳预处理条件。结果表明 ,该法具有去色、去浊率高 ,分离效果佳 ,排除干扰离子能力强 ,分析样品重现性好 ,准确度高 ,操作简便、快捷的优点。  相似文献   
99.
河流水体受污染后,在自然环境因素的影响下由各种物理、化学及生物作用能得到一定的净化。哈尔滨市松花江段河流水质净化作用主要包括稀释、吸附、江底沉积物的机械过滤与吸附和絮凝沉淀作用。哈尔滨市松花江断面正处于河流侵蚀与堆积交替动态平衡中,可不断提供新的活性表面,使河底沉积物的净化作用持久不衰。该特殊的地质条件是本段河流保持较强净化作用的关键,妥善利用水环境净化能力是一种经济有效的水污染控制手段。  相似文献   
100.
铝盐最佳混凝形态及最佳pH范围研究   总被引:38,自引:3,他引:38  
冯利  汤鸿霄 《环境化学》1998,17(2):163-169
本文从理论上分析了铝盐的水解聚合过程,预测了铝盐混凝过程进行时的最佳混凝形态及最佳pH范围,并且通过实验手段分析说明了铝盐的最佳混凝形态,混凝特征及最佳pH范围,得到了较为一致的结果。  相似文献   
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