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221.
Polyaluminum chloride (PAC) was used as coagulant and suspended particles in kaolin water. Online instruments including turbidimeter and particle counter were used to monitor the flocculation process. An evaluation model for demonstrating the impact on the flocculation effect was established based on the multiple linear regression analysis method. The parameter of the index weight of channels quantitatively described how the variation of floc particle population in different size ranges cause the decrement of turbidity. The study showed that the floc particles in different size ranges contributed differently to the decrease of turbidity and that the index weight of channel could excellently indicate the impact degree of floc particles dynamic distribution on flocculation effect. Therefore, the parameter may significantly benefit the development of coagulation and sedimentation techniques as well as the optimal coagulant selection. 相似文献
222.
Polyaluminum chloride (PAC) was used as coagulant and suspended particles in kaolin water. Online instruments including turbidimeter and particle counter were used to monitor the flocculation process. An evaluation model for demonstrating the impact on the flocculation effect was established based on the multiple linear regression analysis method. The parameter of the index weight of channels quantitatively described how the variation of floc particle population in different size ranges cause the decrement of turbidity. The study showed that the floc particles in different size ranges contributed differently to the decrement of turbidity and that the index weight of channel could excellently indicate the impact degree of floc particles dynamic distribution on flocculation effect. Therefore, the parameter may significantly benefit the development of coagulation and sedimentation techniques as well as the optimal coagulant selection. 相似文献
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从活性污泥中筛选出4株产微生物絮凝剂的菌株,将4株菌进行相互复合培养后,发现1号和2号菌株构建的复合菌群(XL1)所产MBF的絮凝率达到65.5%。优化XLI的培养条件及其所产MBF的絮凝条件后,发现XL1在培养温度为35℃、摇床转速为160rpm、培养基初始pH为8.0、菌液用量为15ml/L、种子液接种量为10ml/L、1%CaCl,溶液用量为40ml/L、高岭土悬浮液pH为4.5、静沉时间为12min等的条件下絮凝率可达到92.5%。16S rDNA测序鉴定1号菌属于沙雷菌属(Serratia),2号菌属于芽孢杆菌菌属(Bacillus)。 相似文献
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Zhen Yang Yabo Shang Xin Huang Yichun Chen Yaobo Lu Aimin Chen Yuxiang Jiang Wei Gu Xiaozhi Qian Hu Yang Rongshi Cheng 《环境科学学报(英文版)》2012,24(8):1378-1385
A series of biodegradable amphoteric chitosan-based flocculants (3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CTA) modified carboxymethyl chitosan, denoted as CMC-CTA) with different substitution degrees of CTA were prepared successfully. The content of carboxymethyl groups in each CMC-CTA sample was kept almost constant. The solubility of the various flocculants showed that, higher cationic content of flocculants caused a better solubility. The flocculation experiments using kaolin suspension as synthetic water at the laboratory scale indicated that the substitution degree of CTA was one of the key factors for the flocculation properties. With the increase of cationic content, the flocculants were demonstrated better flocculation performance and lower dosage requirement. Flocculation kinetics model of particles collisions combining zeta potential and turbidity measurements was employed to investigate the effects of the cationic content of the flocculants on the flocculation properties from the viewpoint of flocculation mechanism in detail. Furthermore, flocculation performance using raw water from Zhenjiang part of Yangtze River at the pilot scale showed the similar effects to those at the laboratory scale. 相似文献
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