Electrochemical remediation of copper (II) from an industrial effluent Part II: three-dimensional foam electrodes

A batch recycle removal of copper ions from an industrial effluent by means of copper foam cathodes was tested. A constant current of 750 A was applied to the cell in order to perform the reduction. Copper depletion was investigated at different solution flow rates and a removal greater than 98% was obtained with a flow rate of 1000 l/h. The influence of initial metal concentration on copper deposition and current efficiency is also discussed.     

SC菌剂对废水中Cu~(2 )去除的初步研究

用研制的SC菌剂作生物吸附剂 ,研究了其在不同菌铜比 ,pH、温度及作用时间条件下对Cu2 的去除效果。结果表明 ,在获得的最佳条件下 ,对不同Cu2 浓度的印刷电路板废水中Cu2 的去除效果明显 ,达 95 48%和 86 74%。     

预氯化输水对表面停留性有机物及混凝除藻的影响

针对预氯化这一常用的预氧化方法,考察了表面停留性有机物(S-AOM)在这一过程中对铜绿微囊藻起到的关键作用。同时,探讨了表面停留性有机物及藻的氧化应激对混凝除藻效果的影响。结果表明,预氯化过程可实现适度预氯化的最佳氯投加量,适度预氯化可以在实现脱附S-AOM的同时不损伤藻细胞,强化后续混凝除藻的效果。此外,经过适度预氯化后的藻细胞在远程输水过程中可能会发生程序性死亡,胞内有机物不断泄漏,这仍会对水厂混凝除藻效果产生不利影响。因此,预氧化后藻细胞发生程序性死亡是预氯化强化混凝工艺需要考虑的关键因素。     

沉积物碳氮交互效应及其对河流水体脱氮治理的影响——以厦门市西溪中下游为例

通过福建厦门市内陆河流西溪中下游上覆水及沉积物中碳氮理化指标的时空分布特征,利用碳 (¹³C) 、氮 (¹⁵N) 稳定同位素技术研究了沉积物中厌氧氨氧化 (ANAMMOX) 、反硝化 (denitrification) 及反硝化型厌氧甲烷氧化 (DAMO) 的反应速率及其分布规律。结果表明：西溪中下游上覆水水质总氮为3.02~5.68mg·L⁻¹;利用¹⁵N同位素技术测得西溪中下游沉积物中厌氧氨氧化的平均速率为18.953 μmol·m⁻²·h⁻¹,平均脱氮贡献率为40.13%,反硝化平均速率为27.386 μmol·m⁻²·h⁻¹,平均贡献率为59.87%;起主要脱氮贡献的为反硝化反应,但厌氧氨氧化的脱氮作用仍不可忽视。利用¹³C同位素技术测得西溪中下游沉积物中DAMO反应速率为0~6.122 µmol·m⁻²·h⁻¹,平均速率为1.139 µmol·m⁻²·h⁻¹。这表明西溪中下游沉积物中存在DAMO反应,可在厌氧条件下以硝酸盐作为电子受体将CH₄转化为CO₂。在空间上,西溪中下游DAMO速率存在较大差异性;而在时间上,DAMO速率秋季高于冬春季。反硝化与厌氧氨氧化作用对西溪生态系统中脱氮具有重要意义,DAMO在西溪中下游沉积物虽然反应速率较低,但仍然证明了西溪沉积物生态系统存在连接碳氮循环的微生物反应。反硝化、厌氧氨氧化和DAMO的相互协同,在西溪中下游沉积物脱氮治理及相应过程中的温室气体减排中起到重要作用。     

EVALUATION OF CURRENT TECHNIQUES FOR NUTRIENT REMOVAL FROM WASTEWATERS1

ABSTRACT. A comprehensive evaluation of current techniques for nutrients, nitrogen and phosphorus, removal from wastewaters was conducted by the author under a research project supported by the Office of Water Resources Research, Department of the Interior. The object of this study was to compile and evaluate, under one cover, the available information on current techniques for removing nutrients from wastewaters with emphasis on type of treatment (physical, chemical, biological, or any combination); economics (capital and operating costs); efficiencies, and applications. Due to space limitations, only a brief summary of this work is presented in this paper. A copy of the completion report may be obtained from the author.     

多针-板脉冲放电处理模拟尾气中的NOx

机动车尾气中NOx受到人们普遍关注。采用多针-板放电反应器,研究NOx浓度变化随电气、气体等参数的变化规律,为脉冲放电去除NOx提供一定理论支撑。结果表明：在一定条件下提高脉冲电压有利于NO转化;脉冲重复频率增大可提升NOx去除率,脉冲重复频率达到一定值时NOx去除率增幅不明显;流量增大利于NO转化,不利于NOx去除;随氧浓度的升高NO转化率呈现先降低后升高,NOx去除率逐渐降低。当氧浓度低于5%时,NOx主要是通过NO还原成N2;氧浓度高于5%时,NO主要通过氧化转化为NO2。     

城市污水除磷技术发展

磷是水体富营养化的一个主要限制因素，控制出水中磷的浓度尤其重要。污水除磷方法有生物除磷、化学除磷及生态除磷，也可将各种方法组合使用，如生物一化学除磷、生物一生态除磷等，实际应用中应根据具体情况选择适宜的除磷方法。     

洗涤剂中的磷对环境的影响及对策的探讨

本文介绍了关于洗涤剂中磷对环境影响的两种典型观点和解决的办法,并从经济和环境的角度进行全面的分析,得出合理的结论和建议。     

Germination,Growth, and Nodulation of Sesbania rostrata Grown in Pb/Zn Mine Tailings

Sesbania rostrata in pure and amended Pb/Zn tailings. About 90% of seeds of S. rostrata germinated in pure Pb/Zn tailings, which contained high concentrations of Pb, Zn, Cu, and Cd. Although seedling growth suffered from the adverse environment of Pb/Zn tailings, they became established on tailings stands, in the greenhouse, as well as on the actual tailings dam, and completed their life cycle in 4 months. Dry matter production and nitrogen accumulation was 3200 kg/ha and 69.4 kg/ha, respectively in the actual tailings dam. Applying inorganic fertilizer to Pb/Zn tailings led to no obvious improvement in growth and nodulation of S. rostrata, while tailings amended by river sediment or domestic refuse rich in organic matter improved the growth and nodulation of the species. Azorhizobium caulinodans survived and formed N-fixing stem and root nodules in S. rostrata grown in pure Pb/Zn tailings with a nodule biomass exceeding 300 mg fresh matter per plant.     

不同电子受体除磷污泥相似性与菌群结构研究

分别以硝酸盐、亚硝酸盐、氧气为电子受体,采用3组SBR反应器培养除磷污泥,连续126d的稳定运行表明:以硝酸盐、亚硝酸盐、氧气为电子受体除磷污泥对TP平均去除率分别为84.8%, 78.7%, 87.4%,出水TP平均浓度分别为0.758, 0.931, 0.632mg/L.采用高通量测序技术对不同电子受体除磷污泥的相似性与菌群结构进行了研究,结果表明,以硝酸盐,亚硝酸盐为电子受体的反硝化除磷污泥具有近似的菌群结构,与好氧除磷污泥菌群结构差异较大.基于各样品主导OTUs序列的系统发育关系及其比例的分布,主导微生物主要可以分为5个簇.通过序列比对,在97%的序列相似度条件下,种泥中聚磷菌与聚糖菌序列比例为0.716%与0.368%,以硝酸盐、亚硝酸盐、氧气为电子受体除磷污泥中聚磷菌与聚糖菌序列比例分别为1.78%, 2.53%, 4.80%与1.44%, 1.32%, 30.9%,厌氧-缺氧条件有利于抑制聚糖菌.亚硝酸盐为反硝化除磷污泥电子受体时潜在公共卫生安全隐患.