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11.
本文报导了以玻碳电极为基体的1:12硅钼杂多阴离子薄膜化学修铈电极的制备及其电化学特性。并应用于导数伏安法测定。在4.0×10 ̄(-3)m0l/L(NH_4)_6MO_7O_(24)-6.8×10 ̄(-2)mol/LNa_3Cit-0.48mol/LNHO_3体系中,硅浓度在8.3×10 ̄(-7)~1.7×10 ̄(-3)mol/L范围内与峰电流呈良好线性关系,检测限为8.0×10 ̄(-7)mol/L。对可溶性硅(以SiO_2计)为245.05mg/L的黑液,稀释10倍后,取2.00mL平行测定9次,RSD为0.58%,加标回收率在97.3%~104.4%间。 相似文献
12.
一种复合絮凝剂的絮凝性能及应用研究 总被引:18,自引:1,他引:18
以淀粉为原料,通过化学改性研制出同时兼含羟基、氰基、酰胺基和季铵盐基团的两亲型高分子絮凝剂(ASF),然后加入铝酸纳和硅酸钠,以一定的比例进行复配,制得复合型高分子絮凝剂CF-1,并综合研究了CF-l的絮凝性能。结果表明,CF-1对印染、造纸、皮革、制药等工业废水具有很强的絮凝和脱色效果,废水的色度去除率达96%以上,SS去除率达95%以上,CODCr去除率达74%以上。而且其絮凝性能明显优于阳离子聚丙烯蠢胺(CPAM)、聚合氯化铝(PAC)、硫酸铝以及硫酸亚铁等絮凝剂。 相似文献
13.
Ma Tsz-Chun P. L. Chan H. Lawford H. Chua W. H. Lo Peter Hoifu Yu 《Applied biochemistry and biotechnology》2005,122(1-3):731-739
The first objective of this study was the measurement of physical properties of P(3HB-co-3HV) copolymers with different (hydroxybutyrate)
HB to (hydroxyvalerate) HV ratios produced by Bacillus cereus (TRY2) isolated from activated sludge. The 3HV PHBV copolymers were 0.05, 22.6, 39.2, 54.1, and 69.1 mol%, respectively.
The second objective was to study possible wastewater treatment and production of PHAs at the same time by B. cereus (TRY2) and Pseudomonas spp. (TOB17) (both were isolated from activated sludge), recombinant Bacillus DH5α, and a combination of the above three bacteria. The results were satisfactory; the maximum COD and TOC of the sewage sludge
reduced were 53.5% and 67.5%, respectively. 相似文献
14.
Xiaofang Wan Youming Li Xiaojun Wang Sili Chen Xiaoyang Gu 《European Polymer Journal》2007,43(8):3655-3661
Acrylamide grafted cationic guar gum (CGG-g-PAM), induced by ceric ammonium sulfate, was synthesized using aqueous polymerization technique at 10 °C and the flocculation property was studied with high-turbidity tobacco wastewater (NTU > 4500). Thus five grades of graft copolymers were obtained through alteration of initiator and monomer concentrations in order to understand the effect of molecular weight on flocculation. The grafted copolymer was characterized by FTIR and SEM. Study of DTG demonstrated that CGG-g-PAM had better heat-resistant performance than guar gum, cationic guar gum (CGG) and polyacrylamide. The dosage of polyaluminium chloride (PAC) and CGG-g-PAM, pH value and molecular weight were considered to be the factors that can influence flocculation efficiency. The result showed best flocculation efficiency occurs at pH 5 when the dosage of CGG-g-PAM and PAC are 3.6 ppm and 120 ppm, respectively. The percentage of turbidity and COD removal are 98% and 24% correspondingly, and its flocculating efficiency prevails over that of CGG and cationic polyacrylamide (CPAM). 相似文献
15.
Limited land and insufficient technicians to operate a wastewater treatment system are main restrictions for many factories.
Therefore, an ideal wastewater treatment method for a small or land-limited factory must possess merits such as high performance
efficiency, high organic loading rate, little odor, simple operation, easy maintenance, and little land required (simultaneously).
An entrapment technique to immobilize mixed microorganisms to treat organic wastewater, which was developed in the present
work, possesses these characteristics. This project was done on a laboratory scale. The microorganisms were activated sludge
(an undefined mixture of microorganisms obtained directly from a domestic wastewater treatment plan) and the mixed microorganisms
were immobilized in cellulose triacetate by means of an entrapment technique to treat organic wastewater from food industry.
After wastewater was treated by this system, the SCOD (soluble COD) removal efficiency of 81% evaluated samples exceeded 80%
in 1.5 ± 0.9 g SCOD/L/d of the volumetric loading rate and 7–10 h for the hydraulic retention time. This wastewater treatment
method can be applied to other organic industrial wastewater. 相似文献
16.
水淬渣-累托石颗粒吸附材料的制备及应用 总被引:1,自引:0,他引:1
研究了水淬渣-累托石颗粒吸附材料制备工艺条件、再生方法及其去除铜冶炼工业废水中重金属的条件.试验结果表明,累托石与水淬渣的比例为1∶1,另加入10%的添加剂(IS)和50%的水,焙烧温度为400℃时,制成的颗粒吸附材料体积密度为1.06kg/m3,显气孔率为62.29%,吸水率为58.82%,抗压强度为2.22Mpa,吸附效果好,散失率较低.在未调节铜冶炼工业废水pH值的条件下,颗粒吸附材料用量为0.05g/cm3,反应时间为40min,吸附温度为25℃(常温)时,Cu2 、Pb2 、Zn2 、Cd2 、Ni2 的去除率分别为98.2%、96.3%、78.6%、86.2%、64.2%,处理后的水符合国家污水综合排放标准(GB8978-1996)一级标准.颗粒吸附材料对Zn2 、Cu2 有很好的选择性.吸附饱和的颗粒吸附材料用1mol/L氯化钠溶液再生效果好.该颗粒吸附材料具有分离容易、可重复使用、处理效果好、应用前景广阔的优点. 相似文献
17.
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19.
城市污水处理过程中有机污染物三维荧光特性的变化规律 总被引:18,自引:0,他引:18
采用三维荧光光谱法研究了城市污水处理过程中溶解性有机物的三维荧光特性变化规律。研究结果表明,生活污水中荧光类溶解性有机物主要以类蛋白有机物、UV腐殖质和可见腐殖质为主;污水生物处理前后特征荧光峰中心位置和强度均发生明显的改变,表明污水中有机物的相对组成和含量随生物处理过程而变化。三维特征荧光参数可以反映污水处理过程中污染物的种类、性质和含量变化等丰富信息。其测定迅速简便、灵敏度高,可用于污水处理效果的定性分析、定量评价,易于实现污水处理过程的实时在线监测,指导污水处理工艺的设计、运行、管理和控制。 相似文献
20.
The effect of the shear rate on pullulan production from beet molasses by Aureobasidium pullulans P56 in an airlift reactor was investigated. A maximum polysaccharide concentration (18.5 g/L), biomass dry weight (14.0 g/L),
polysaccharide yield (38.5%), and sugar utilization (96%) was achieved at a shear rate of 42 s−1. A. pullulans grown on beet molasses produced a mixture of pullulan and other polysaccharides. The highest value of pullulan proportion
(30% of total polysaccharide) was obtained at a low shear rate (42 s−1). The apparent viscosity of the fermentation broth increased as the shear rate increased up to 42 s−1 and then decreased. On the other hand, the dissolved oxygen concentration and the volumetric mass transfer coefficient increased
with the increase of the shear rate from 21 to 84 s−1. The external addition of L-glutamic acid, olive oil, and Tween-80 improved significantly the production of crude polysaccharide (27.0 g/L), but the
pullulan content of the polysaccharide was low (20%). 相似文献