Treatment of a dyeing wastewater from a woolen mill using an A/O membrane bio-reactor

An anaerobic/oxic membrane bioreactor (A/O MBR) was used for treatment of dyeing wastewater from a woolen mill.COD and color of the wastewater were 54-473 mg/L and 40-400 dilution time (DT) respectively. The ratio of BOD5/COD was less than 0.13. By the A/O MBR process, the average removal of COD, BOD5, color and turbidity was 82％, 96％, 71％ and 99％, respectively. The average COD, BOD5, color and turbidity of effluent was 37 nag/L, 0.8 mg/L, 40 DT and 0.44 NUT respectively. The effluent COD met the local standard of reuse water in Beijing, China. The average COD volume load of the anaerobic biological tank was 0. 0483 kgCOD/(m3·d) and that of the aeration tank of the MBR was 0. 3589 kgCOD/(m3·d). The sludge load of the MBR was 0.19 kgCOD/(kg· MLSS· d) on average and the maximum of that was 0.4 kgCOD/( kg· MLSS· d).The flux of the A/O membrane bioreactor could be remained at larger than 50 L/(h· m2· 0.1MPa). The results indicated that A/O membrane bioreactor has technical feasibility for treatment of woolen mill wastewater.     

电感耦合等离子体质谱法测定饮用水中的硒

应用电感耦合等离子体质谱法测定饮用水中的硒元素。结果表明,高能碰撞模式(HEHe)较碰撞/反应池气体模式(He模式)消除干扰效果更好;在HEHe模式下,~(78)Se在0.5~100μg/L范围内线性良好,相关系数0.999 9,方法检出限为0.06μg/L,相对标准偏差为0.4%~0.8%,加标回收率为97.1%~103.2%。方法性能指标均能较好满足饮用水中Se的定量测试要求。     

用味精生产废水培养好氧颗粒污泥

以厌氧颗粒污泥为接种污泥,采用味精生产废水进行培养,在SBR中以逐渐降低污泥沉淀时间的方法成功培养出好氧颗粒污泥。实验结果表明：污泥接种65 d后,出现细小的好氧颗粒污泥,呈黄褐色,95 d后颗粒污泥趋于成熟,粒径达0.6 mm左右,且周围存在大量原生动物;运行95 d后MLSS提高至8.00 g/L,SVI降至30.00 mL/g左右;成熟后的好氧颗粒污泥对味精生产废水中的COD和NH₃-N具有良好的去除效果,出水COD和ρ（NH₃-N）分别为80 mg/L和2 mg/L左右。     

Production of Poly(l-Lactide)-Degrading Enzyme by Amycolatopsis orientalis ssp. orientalis and Its Catalytic Ability in Biological Recycling of Poly(l-Lactide)

The fermentation conditions for poly(l-lactide) (PLA)-degrading enzyme production by Amycolatopsis orientalis ssp. orientalis were statistically optimized by response surface methodology. The optimal value of the most important factors was 0.39 % PLA and 0.34 % gelatin for 2.81 days of cultivation. Under these conditions, the model predicted a PLA-degrading activity of 155.30 U/l. The verification showed the production amount of 154.2 U/l. The crude enzyme from A. orientalis ssp. orientalis showed potent PLA-degrading ability, which is efficient for the biological recycling of PLA. Up to 4,000 mg/l of PLA granule was completely degraded within 5 days at 45 °C by the crude enzyme. l-lactic acid (600 mg/l) was obtained as a degradation product of PLA after only 2 h of incubation. The results indicated that the crude PLA-degrading enzyme from A. orientalis ssp. orientalis has the potential to degrade PLA to lactic acid for the recycling of PLA industry and waste disposal.     

Hydrothermal solidification behavior of municipal solid waste incineration bottom ash without any additives

Municipal solid waste incineration (MSWI) bottom ash could be solidified with and without slaked lime (calcium hydroxide) addition by a hydrothermal method under steam pressure of 1.56 MPa at 200 °C for up to 72 h. Experimental results showed that CSH gel or tobermorite exerted a main influence on strength development, and without any additives CSH gel was easy to form, while slaked lime addition favored to form tobermorite. Tobermorite seemed to exert a larger effect on the strength development than CSH gel. Leaching results showed that the concentrations of heavy metals dissolved from the solidified specimens were effectively reduced after hydrothermal processing. The immobilization was mainly due to the tobermorite or CSH gel formation, and Pb²⁺ and Zn²⁺ seemed to be fixed more readily than Cr⁶⁺, which might be the reason that the structural Ca²⁺ within tobermorite or CSH gel was exchanged by Pb²⁺ and Zn²⁺ more easily than Cr⁶⁺. In addition, there existed a close relationship between leaching concentration and strength enhancement, and a higher strength seemed to exert a larger effect on immobilization of heavy metals.     

The platelet-activating factor acetylhydrolase gene derived from Trichoderma harzianum induces maize resistance to Curvularia lunata through the jasmonic acid signaling pathway

Platelet-activating factor acetylhydrolase (PAF-AH) derived from Trichoderma harzianum was upregulated by the interaction of T. harzianum with maize roots or the foliar pathogen Curvularia lunata. PAF-AH was associated with chitinase and cellulase expressions, but especially with chitinase, because its activity in the KO40 transformant (PAF-AH disruption transformant) was lower, compared with the wild-type strain T28. The result demonstrated that the colonization of maize roots by T. harzianum induced systemic protection of leaves inoculated with C. lunata. Such protection was associated with the expression of inducible jasmonic acid pathway-related genes. Moreover, the data from liquid chromatography-mass spectrometry confirmed that the concentration of jasmonic acid in maize leaves was associated with the expression level of defense-related genes, suggesting that PAF-AH induced resistance to the foliar pathogen. Our findings showed that PAF-AH had an important function in inducing systemic resistance to maize leaf spot pathogen.     

Herbicide Roundup® and its main constituents cause oxidative stress and inhibit acetylcholinesterase in liver of Carassius auratus

Roundup® is a glyphosate-based herbicide containing a mixture of surfactants. This paper evaluates the toxic effects of Roundup® and its main constituents on the goldfish, Carassius auratus, after 7 days exposure. Fish were exposed to 0.16, 0.032 and 0.0064 mg/L of Roundup® [containing 41% isopropylamine salt of glyphosate (G.I.S) and 18% polyoxyethylene amine (POEA)], G.I.S, and POEA. Their livers were taken for determining reactive oxygen species (ROS), superoxide dismutase (SOD) activity, malondialdehye (MDA) content and acetylcholinesterase (AChE) activity. Hydroxyl radical (·OH) could be induced by exposing Roundup® at a rate of 43%–111%, G.I.S at 90%–124% and POEA at142%–157%. A decreased SOD activity was observed in fish exposed to G.I.S and POEA. The contents of MDA significantly increased when exposed to Roundup® at all concentrations, 0.16 mg/L G.I.S and 0.032 mg/L POEA. The exposure led to an inhibition of AChE in livers overall during the experimental periods. POEA was more toxic than Roundup® or G.I.S during this experiment. AChE and ·OH are supposed to be sensitive biomarkers of the exposure of Roundup® and its main constituents to C. auratus.     

Hydrogeo-chemical impacts of air sparging remediation on a semi-confined aquifer: Evidences from field monitoring and modeling

Air sparging (AS) was explored for remediation of a petroleum contaminated semi-confined groundwater system in NE China. Physical, hydro-chemical and hydraulic behaviors in subsurface environment during AS were investigated with support of modeling to understand the hydrogeo-chemical impacts of AS on the aquifer. The responses of groundwater, dissolved oxygen and temperature indicated that the radius of influence of AS was up to 8–9 m, and a 3D boundary of the zone of influence (ZOI) was accordingly obtained with volume of 362 m³. Water mounding unlike normal observations was featured by continuous up-lift and blocked dissipation. AS induced water displacement was calculated showing no obvious spreading of contaminant plume under this AS condition. Slug tests were employed before and after AS to reveal that the physical perturbation led to sharp increase in permeability and porosity. Modeling indicated that the regional groundwater flow field was not affected by AS except the physical perturbation in ZOI. Hydro-chemically increase of pH and Eh, and reduction of TDS, electrical conductivity and bicarbonate were observed in ZOI during AS. PHREEQC modeling inferred that these chemical phenomena were induced by the inorganic carbon transfer during air mixing.     

Enhanced-electrokinetic remediation of copper–pyrene co-contaminated soil with different oxidants and pH control

Electrokinetic (EK) remediation has potential to simultaneously remove heavy metals and organic compounds from soil, but the removal percent of these pollutants is very low in general if no enhancing treatment is applied. This study developed a new enhanced-EK remediation technology to decontaminate a heavy metal–organic compound co-contaminated soil by applying different oxidants and pH control. A red soil was used as a model clayed soil, and was spiked with pyrene and Cu at about 500 mg kg^?1 for both to simulate real situation. Bench-scale EK experiments were performed using four oxidants (H₂O₂, NaClO, KMnO₄, and Na₂S₂O₈) and controlling electrolyte pH at 3.5 or 10. After the treatments with 1.0 V cm^?1 of voltage gradient for 335 h, soil pH, electrical conductivity, and the concentrations and chemical fractionations of soil pyrene and Cu were analyzed. The results showed that there was significant migration of pyrene and Cu from the soil, and the removal percent of soil pyrene and Cu varied in the range of 30–52% and 8–94%, respectively. Low pH favoured the migration of soil Cu, while KMnO₄ was the best one for the degradation of pyrene among the tested oxidants, although it unfortunately prevented the migration of soil Cu by forming Cu oxide. Application of Na₂S₂O₈ and to control the catholyte pH at 3.5 were found to be the best operation conditions for decontaminating the Cu-pyrene co-contaminated soil.     

基于最佳管理实践的中新生态城面源污染控制措施优选研究

基于最佳管理实践（BMP）理念和方法,以中新生态城为例,采用多属性决策分析方法的ELECTRE-Ⅲ方法和模型,采用VisualBasic语言自行编制辅助计算机程序,对该地区8种雨水控制管理措施进行了优化比选。优选结果表明,对于中新生态城,8种雨水控制管理措施的优选排序为：湿地〉地下蓄水库〉人渗沟〉可渗透路面砖〉道路边沟〉绿色屋顶〉下凹绿地〉绿化缓冲带。