低浓度LAS对活性污泥性质和去除污染物行为的影响

采用SBR处理模拟废水,考察了不同浓度阴离子表面活性剂——烷基苯磺酸钠（LAS）对反应器活性污泥的影响。实验结果表明,低浓度表面活性剂LAS的投加,有利于提高SBR中活性污泥对COD和氨氮处理效率,并且活性污泥的沉降性以及微生物活性也随着LAS投加浓度的升高而升高。但是,当LAS的投加浓度过高时（1 mg/L）,污泥表面产生起泡、乳化和微粒悬浮等现象,使大量固体陷入漂浮泡沫层,降低曝气池的充氧效率,最终导致污泥解体,沉降性变差,活性下降。     

基于成本-效能分析的氧化沟工艺运行条件优化

在利用ASM2d模型对城市污水处理厂氧化沟工艺进行动态模拟的基础上,将曝气能耗、污泥产量与出水水质超标率整合为一个综合效能指数,对该工艺进行了成本-效能分析。最优运行策略为:3～10月温度高于15℃时运行8台曝气转刷,其余时间段运行10台转刷,同时剩余污泥排放量控制在250 m3/d。这一策略能够使出水NH4-N和TN的超标率分别低于5%和2%,保证出水TP的持续达标,与常规运行策略相比,在明显降低氮磷超标率的同时,节省曝气能耗约12%。     

一种新型微生物菌剂处理生活污水

利用从食材中筛选纯化的特定微生物制成复合菌剂,在自然、厌氧和曝气3种不同的供氧条件下,添加不同比例的菌剂处理生活污水,以COD和氨氮浓度为参考指标,考察菌剂对污水的净化效果,并分析其原因。结果表明:(1)菌剂投加量在0.5‰～1‰时对污水中COD的去除具有明显促进作用,自然、厌氧和曝气3种条件下,COD去除率最大分别提高了8.77%、11.22%和11.11%;(2)氨氮的去除效果受反应条件影响很大,厌氧条件下菌剂对污水中氨氮的去除作用不明显,自然和曝气条件下,菌剂对氨氮去除效果显著,去除率增幅最高分别达到22.6%和52.28%;(3)以0.5‰的菌剂投加量曝气处理2 d,COD和氨氮的去除率可以分别提高11.11%和14.13%,初步研究显示,该菌剂对生活污水具有较好的净化效果。     

Comparative and competitive adsorption of Cr(VI), As(III), and Ni(II) onto coconut charcoal

This study evaluates the behavior of coconut charcoal (AC) to adsorb Cr(VI), As(III), and Ni(II) in mono- and multicomponent (binary and ternary) systems. Batch experiments were carried out for mono- and multicomponent systems with varying metal ion concentrations to investigate the competitive adsorption characteristics. The adsorption kinetics followed the mechanism of the pseudo-second-order equation in both single and binary systems, indicating chemical sorption as the rate-limiting step of adsorption mechanism. Equilibrium studies showed that the adsorption of Cr(VI), As(III), and Ni(II) followed the Langmuir model and maximum adsorption capacities were found to be 5.257, 0.042, and 1.748 mg/g, respectively. In multicomponent system, As(III) and Ni(II) adsorption competed intensely, while Cr(VI) adsorption was much less affected by competition than As(III) and Ni(II). With the presence of Cr(VI), the adsorption capacities of As(III) and Ni(II) on AC were higher than those in single system and the metal sorption followed the order of Ni(II)?>?As(III)?>?Cr(VI). The results from the sequential adsorption–desorption cycles showed that AC adsorbent held good desorption and reusability.     

混合胺MEA＋DETA吸收CO2的影响因素

以MEA为主体,DETA为添加剂,考察1h内,在温度298～338K,压力300～700kPa,混合胺溶液初始浓度（质量分数）4％～20％范围内,MEA＋DETA不同配比的混合吸收剂吸收CO2的特性。获得MEA＋DETA混合胺吸收CO2的最佳吸收条件为：308K、500kPa、总胺质量浓度为20％,MEA与DETA的配比为8：2。     

PCF型湿式脱硫除尘器入口结构优化

以PCF型湿式脱硫除尘器为物理模型,利用Fluent软件包,采用RNGк-ε湍流模型和SIMPLEC算法,对装置内三维流场进行数值模拟.模拟结果发现,原倾斜入口(A)的装置内烟气分布不均匀.提出了水平入口(B)、左入口(C)、右入口(D)3种优化结构,并分别对A、B、C、D入口装置内气流速度、湍流强度与压降进行了模拟分析.结果表明,C、D入口使装置内气流速度分布更加均匀,且增强了装置内湍流强度,但C入口会导致压降增加,因此最佳入口为D.最后,针对入口D装置中的低速区,模拟分析了30°、45°与54°3种不同切入角度,得出45 °效果最佳.     

大孔树脂NKA-II对双酚A的吸附性能

研究了大孔树脂NKA-II对双酚A（BPA）的吸附性能,考察了吸附过程的动力学、热力学及树脂的再生性能。BPA溶液呈弱酸性,不需调节pH可直接进行吸附。BPA在大孔树脂NKA-II上的吸附过程可用准二级动力学方程很好地描述。树脂对BPA的吸附是吸热反应,符合Freundlich等温吸附方程,吸附过程属于可自发进行的物理吸附。BPA的吸附过程中同时存在着溶剂的解吸。大孔树脂NKA-II具有良好的重复使用性能,新树脂的平衡吸附量为10.44 mg/g,再生20次后平衡吸附量仍为10.43 mg/g。     

城市污泥微波干化工艺及干化特性研究

采用微波和烘箱结合及全程烘箱2种方式对城市污泥干化进行对比研究,考察了不同粒径、微波干化预处理、预处理时间及烘箱温度对污泥干燥特性的影响。结果表明,同一温度条件下,微波预处理时间越长,污泥干化速率越快。最优条件下,全程烘箱污泥达到最大干化速率的含水率为77%。微波干燥污泥具有时间短、干燥速率大的特点,微波和烘箱结合对比全程烘箱干化速率高且能耗低。     

不同粒径炉渣对磷的静态吸附

研究了不同粒级炉渣对含磷废水的静态等温吸附性能,为其在污水处理领域的有效利用和合理级配提供理论依据。经筛分得到<0.2 mm、0.2~0.45 mm、0.45~0.9 mm、0.9~2 mm、2~4 mm、4~6 mm、≥6 mm的7个粒级的供试炉渣,其中0.9~4 mm粒级占总量的64.54%。XRD、XRF分析显示,各粒级炉渣物相组成相似,<0.2 mm粒级炉渣中活性铝含量最高。静态吸附实验表明,炉渣对磷素的最大吸附量为4 021 mg/kg,最佳吸附时间为24 h;Langmuir和Freundlich吸附等温线可较好地拟合各粒级炉渣对溶液中磷素的吸附,而小于0.9 mm粒级炉渣具有更高的拟合度;炉渣粒径越小,吸附能力越强,<0.2 mm粒级炉渣的理论饱和吸附容量达14 084 mg/kg,≥6 mm粒级炉渣吸附磷素能力差;受粒径、溶液含磷浓度等因素影响,炉渣的平均理论吸附容量为1 142.4 mg/kg。     

Toxicity of Cu (II) to the green alga <Emphasis Type="Italic">Chlorella vulgaris</Emphasis>: a perspective of photosynthesis and oxidant stress

The toxic effects of Cu (II) on the freshwater green algae Chlorella vulgaris and its chloroplast were investigated by detecting the responses of photosynthesis and oxidant stress. The results showed that Cu (II) arrested the growth of C. vulgaris and presented in a concentration- and time-dependent trend and the SRichards 2 model fitted the inhibition curve best. The chlorophyll fluorescence parameters, including qP, Y (II), ETR, F _v /F _m , and F _v /F ₀, were stimulated at low concentration of Cu (II) but declined at high concentration, indicating the photosystem II (PSII) of C. vulgaris was destroyed by Cu (II). The chloroplasts were extracted, and the Hill reaction activity (HRA) of chloroplast was significantly decreased with the increasing Cu (II) concentration under both illuminating and dark condition, and faster decline speed was observed under dark condition. Activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were also significantly decreased at high concentration Cu (II), companied with a large number of reactive oxygen species (ROS) production. All these results indicated a severe oxidative stress on algal cells occurred as well as the effect on photosynthesis, thus inhibiting the growth of algae, which providing sights to evaluate the phytotoxicity of Cu (II).