铜陵尾矿土壤重金属污染物的固定修复

化学固定法通过向土壤中添加一定的固定剂,降低重金属有效态含量达到修复土壤重金属污染的目的。利用石灰、炉渣和稻草作为土壤重金属固定剂,通过土壤与固定剂的混合来修复铜陵Cu、Cd、Zn污染土壤,分析石灰、炉渣和稻草对土壤有效态Cu、Cd、Zn的固定修复效率和土壤微生物代谢呼吸率的影响。结果表明:除石灰与炉渣单独使用时对Cu固定修复效率低,以及稻草单独使用对Cd与Zn的固定修复效率也较差外,固定剂能够显著的降低有效态Cu、Cd、Zn含量(〖WTBX〗p〖WTBZ〗<005),尤其石灰、煤渣和稻草的混合物能够最为高效的降低有效态Cu、Cd、Zn含量,固定修复效率分别为9428%、7810%和 9857%,同时还能显著提高土壤微生物的代谢呼吸率(〖WTBX〗p〖WTBZ〗<005),增大微生物的活性。Pearson’s相关系数分析进一步表明在重金属污染的酸性土壤中,同时增加碱性物质和有机质含量能够较为高效地降低有效态重金属含量,增强土壤微生物抗重金属胁迫和毒性耐受能力,利于土壤的复垦再利用     

Removal of emulsified fuel oils from brackish and pond water by dissolved air flotation with and without polyelectrolyte use: pilot-scale investigation for estuarine and near shore applications

In coastal areas, estuaries, and inland waters, dispersant use after oil spills is not allowed due to sensitivity of the ecosystems. The purpose of this study was to investigate the removal of emulsified fuel oils from brackish and pond water by dissolved air flotation (DAF) with and without use of coagulants. Experiments were conducted with a 60 L DAF system. Fuel oil-water emulsions were prepared with regular unleaded gasoline, jet fuel, and diesel fuel mixed at 1:1:1 (v/v/v) ratio. Batch and continuous runs were conducted at air pressurization of 354.6 kPa. During both batch and continuous modes, significant petroleum hydrocarbon (PHC) removal was achieved within 10 min. Coagulant addition initially increased the PHC removal by about 5-15%. However, effectiveness of the coagulant was not significant after 20 min due to breakage of the aggregates. In general, the pond water had higher PHC removal than the brackish water. With longer run times, PHC removal improved slightly and the effluent contained increasing fractions of higher molecular weight compounds indicating that PHC removal was due to both DAF and stripping processes. Results indicate that DAF process can be effective both with and without the use of coagulants for removing PHCs from brackish and pond waters.     

锰砂催化氧化Fe(Ⅱ)为Fe(Ⅲ)的研究

探讨了锰砂催化亚铁反应的动力学特征及其反应机理。结果表明,锰砂作催化氧化剂,亚铁氧化反应速率可达３０９ｇ／（Ｌ．ｈ）,８０％以上的亚铁在反应初的１５ｍｉｎ内被除去。每ｇ锰砂的饱和氧化亚铁量在到０．４９－０．７３ｇ。     

Bubble performance of a novel dissolved air flotation(DAF) unit

ES-DAF, a novel DAF with low cost, high reliability and easy controllability, was studied. Without a costly air saturator, ESDAF consists of an ejector and a static mixer between the pressure side and suction side of the recycle rotary pump. The bubble size distribution in this novel unit was studied in detail by using a newly developed CCD imagination through a microscope. Compared with MDAF under the same saturation pressure, ES-DAF can produce smaller bubble size and higher bubble volume concentration, especially in lower pressure. In addition, the bubble size decreases with the increase of reflux ratio or decrease of superficial air-water ratio. These results suggested that smaller bubbles will be formed when the initial number of nucleation sites increases by enhancing the turbulence intensity in the saturation system.     

湿法冶锌废渣中有价金属回收研究进展

综述了电化学法、沉淀法、吸附法、离子交换法、浮选法和液膜分离法等在分离回收湿法冶锌废渣中有价金属及相关领域的研究进展,阐述了吸附法和液膜分离法的原理,指出了湿法冶锌废渣中有价金属回收的研究方向:吸附法拥有巨大的潜力,是今后的研究重点;离子交换法的研究热点是开发新型树脂基体;液膜分离法的研究方向一是提升液膜稳定性,二是研发能够高效单一分离有价金属的载体。     

铀尾矿库中238U运移数值模拟

铀尾矿库退役后要进行环境治理和长期监测,对库中放射性核素进行模拟可以为放射性废物安全管理提供科学依据.笔者采用有限元法对尾矿中238U在地下水中的迁移情况进行了模拟,结果表明,尾矿库治理后1 000 a,238U迁移到距尾矿库边缘183 m的地方,未到达附近河流.     

化学药剂对吸入式气浮净化机除油浮选动力学的影响

本研究在实验室装置上着重考察了化学药剂对吸入式气浮净化机除油浮选动力学的影响。研究结果表明化学药剂对浮选速率常数有明显影响,不同化学药剂及用量其影响效果不同。     

镉铜污染尾矿土中添加耐镉铜菌剂J5后微生物区系多样性的变化

采用酶解法和化学裂解法相结合的方法从安徽铜陵镉铜污染尾矿土中提取出土壤微生物基因组总DNA,并应用PCR-DGGE技术对比研究尾矿土中添加外源硫酸镉、硫酸铜和耐镉铜菌剂J5(Pseudomonassp.)后微生物区系多样性的变化.结果表明,尾矿土中微生物基因组总DNA分子量大小为21kb左右,未复垦的尾矿砂中微生物总DNA量较少,CdSO4处理后的尾矿土中微生物基因组总DNA量明显下降,而添加菌剂J5的尾矿土中微生物基因组总DNA量上升.DGGE电泳图谱进一步显示,尾矿土样中添加镉离子使图谱条带减少,分析表明尾矿土中的细菌种类数减少;而添加菌剂J5使图谱中条带明显增加,表明菌剂J5可提高尾矿土中土著微生物的活性和群落丰富度,可用于复合重金属污染尾矿区的生态恢复.     

Leaching characteristics of copper flotation waste before and after vitrification

Copper flotation waste from copper production using a pyrometallurgical process contains toxic metals such as Cu, Zn, Co and Pb. Because of the presence of trace amounts of these highly toxic metals, copper flotation waste contributes to environmental pollution. In this study, the leaching characteristics of copper flotation waste from the Black Sea Copper Works in Samsun, Turkey have been investigated before and after vitrification. Samples obtained from the factory were subjected to toxicity tests such as the extraction procedure toxicity test (EP Tox), the toxicity characteristic leaching procedure (TCLP) and the "method A" extraction procedure of the American Society of Testing and Materials. The leaching tests showed that the content of some elements in the waste before vitrification exceed the regulatory limits and cannot be disposed of in the present form. Therefore, a stabilization or inertization treatment is necessary prior to disposal. Vitrification was found to stabilize heavy metals in the copper flotation waste successfully and leaching of these metals was largely reduced. Therefore, vitrification can be an acceptable method for disposal of copper flotation waste.     

气浮-水解-序批式活性污泥法处理高浓度特种丙烯酸废水

采用气浮—水解—序批式活性污泥法(SBR)处理高浓度特种丙烯酸废水,研究了投加生活污水对处理效果的影响及厌氧水解时间、SBR曝气时间、污泥负荷等因素对COD去除率的影响,结果表明,按1∶1体积比投加生活污水,厌氧水解时间2d,序批式活性污泥法曝气时间10h(进水后期曝气1h,共曝气11h),污泥负荷小于或等于0.08kg/(kg.d)时,出水COD小于85m g/L,满足处理要求。