Fenton氧化法深度处理抗生素废水二级出水

采用Fenton氧化法对青霉素和土霉素混合废水二级处理出水进行深度处理,通过正交和单因素实验研究了废水初始反应pH值、H2O2投加量、Fe2+/H2O2摩尔比及反应时间等因素对废水处理效果的影响。实验结果表明,Fenton氧化法处理的最佳反应条件为:初始pH值4、H2O2(30%)投加量50 mL/L、Fe2+/H2O2摩尔比1/20和反应时间60 min,处理后出水COD小于120 mg/L,COD去除率在75%以上,急性毒性(HgCl2毒性当量)小于0.07 mg/L,满足《发酵类制药工业水污染物排放标准》(GB21903-2008)表2标准要求。     

小型好氧堆肥设备处理有机垃圾

针对我国生活垃圾的特点,提出了厨余等有机生活垃圾单独收集,在产生源头进行好氧堆肥处理。研制了好氧堆肥设备,由加热装置、通风装置、冷凝水收集和回灌装置,以及与该生物堆肥设备配套的生物过滤除臭装置、自控系统和数据采集软件几部分构成。自控系统由氧气、温度、湿度三路传感器以及2个控制器构成,并与加热装置、通风装置连接,能满足物料加热、供氧和散热的要求。本研究通过为期30 d的试运行实验表明,物料快速升温并稳定保持在高温阶段(50～60℃),物料中的氧气浓度保持在14%～16%范围内。在堆肥实验结束时,物料的含水率降至36.4%,有机质含量降至49%,另外,通过好氧速率指标也可判定物料达到腐熟。     

Influence of root-exudates concentration on pyrene degradation and soil microbial characteristics in pyrene contaminated soil

The effect of ryegrass (Lolium perenne L.) root-exudates concentration on pyrene degradation and the microbial ecological characteristics in the pyrene contaminated soil was investigated by simulating a gradually reducing concentration of root exudates with the distance away from root surface in the rhizosphere. Results showed that, after the root-exudates were added 15 d, the pyrene residue in contaminated soil responded nonlinearly in the soils with the same pyrene contaminated level as the added root-exudates concentration increased, which decreased first and increased latter with the increase of the added root-exudates concentration. The lowest pyrene concentration appeared when the root exudates concentration of 32.75 mg kg(-1) total organic carbon (TOC) was added. At the same time, changes of microbial biomass carbon (MBC, C(mic)) and microbial quotient (C(mic)/C(org)) were opposite to the trend of pyrene degradation as the added root-exudates concentration increased. Phospholipid fatty acid (PLFA) analysis revealed that bacteria was the dominating microbial community in pyrene contaminated soil, and the changing trends of pyrene degradation and bacteria number were the same. The changing trend of endoenzyme-dehydrogenase activity was in accordance with that of soil microbe, indicating which could reflect the quantitative characteristic of detoxification to pyrene by soil microbe. The changes in the soils microbial community and corresponding microbial biochemistry characteristics were the ecological mechanism influencing pyrene degradation with increasing concentration of the added root-exudates in the pyrene contaminated soil.     

Assessment of waters and sediments impacted by drainage at the Young Dong coal mine site, South Korea

Introduction  

This study focused on the assessment of the geochemistry and hydrology of the Imgok Creek–Young Dong tributary for the design of a field coal mine drainage treatment system.     

利用剩余活性污泥生产一次性可降解材料

为了缓解污水处理厂日益严重的污泥处置难题,实现剩余活性污泥的无害化、减量化、稳定化、资源化利用。采用SBR系统对剩余活性污泥进行10 d的驯化,加入4.0 g/L的乙酸钠作为发酵培养基碳源和前体物质,累积聚羟基烷酸酯(polyhydroxyalkanoates,PHA)。30℃好氧发酵10 h后,PHA积累达1 125 mg/L,占污泥浓度(MLSS)的质量分数为35.7%。然后经过离心、烘干、粉碎后模压成型加工成一次性使用的可生物降解材料。使用正交实验进行优化,结果表明:其最佳的物料配比和模压条件为:干污泥57%;稻草纤维20%;聚乙烯醇(PVA)19%;硬脂酸钡2%;氧化钙2%;最佳工艺条件为100℃,加热1.5 h,此时加工出来的产品具有最优的抗压强度和拉伸强度。以本方法制成的可生物降解花盆其所含细菌总数、粪大肠菌群、蛔虫卵死亡率均达到国标所规定的污泥农用生物安全要求;另外,试样中未检出病毒;其重金属含量也达到国标所规定的污泥农用标准;其可生物降解性能达到了可降解材料的要求。因而本研究制备的一次性使用可降解花盆具有较好的开发和应用价值。     

凹凸棒石粘土固定辣根过氧化物酶处理含酚废水

采用凹凸棒石粘土、可溶性淀粉和工业水玻璃作为制备凹凸棒石粘土基颗粒的材料,并将制备的凹凸棒石粘土基颗粒进行改性,得到了改性后的凹凸棒石基多孔材料,并将其作为固定辣根过氧化物酶的载体,再应用于含酚废水的处理研究,取得了良好的效果。实验结果表明,辣根过氧化物酶的最佳固定化条件为:单位酶活载体量1 mg、固定化时间1.5小时、固定pH值5。并且在固定化酶循环使用6次后,苯酚去除率仍能达到62.3%。     

Evaluating the degradation of the herbicides picloram and 2,4-D in a compartmentalized reactive biobarrier with internal liquid recirculation

Tordon is a widely used herbicide formulation of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-amino-3,5,6-trichloropicolinic acid (picloram), and it is considered a toxic herbicide. The purposes of this work were to assess the feasibility of a microbial consortium inoculated in a lab-scale compartmentalized biobarrier, to remove these herbicides, and isolate, identify, and evaluate their predominant microbial constituents. Volumetric loading rates of herbicides ranging from 31.2 to 143.9 g m^?3 day^?1, for 2,4-D, and 12.8 to 59.3 g m^?3 day^?1 for picloram were probed; however, the top operational limit of the biobarrier, detected by a decay in the removal efficiency, was not reached. At the highest loading rates probed, high average removal efficiencies of 2,4-D, 99.56?±?0.44; picloram, 94.58?±?2.62; and chemical oxygen demand (COD), 89.42?±?3.68, were obtained. It was found that the lab-scale biofilm reactor efficiently removed both herbicides at dilution rates ranging from 0.92 to 4.23 day^?1, corresponding to hydraulic retention times from 1.087 to 0.236 days. On the other hand, few microbial strains able to degrade picloram are reported in the literature. In this work, three of the nine bacterial strains isolated cometabolically degrade picloram. They were identified as Hydrocarboniphaga sp., Tsukamurella sp., and Cupriavidus sp.     

面源磷负荷改进输出系数模型及其应用

传统的输出系数模型是模拟较大流域面源污染的有效手段,但它假设同一土地利用类型的输出系数相同,忽视了营养物径流和截留过程中其他流域特征对输出系数空间分布的影响,难以为流域分区管理提供依据。在传统输出系数模型基础上,引入产污因子（CI）和截留因子（RI）,校正地形、降雨、植被缓冲带对面源磷流失空间格局的影响。用改进输出系数模型模拟滇池流域面源磷负荷并将模拟结果应用于流域管理。结果表明,改进的输出系数模型能更好地模拟面源磷污染的空间格局,识别出面源总磷的关键风险区--湖滨平原地带以及与入滇河流邻近的山谷、台地。以2008年滇池流域面源总磷的模拟结果（3525 t）为基准,若单位面积磷肥施用量减少20%,面源总磷负荷将减少86%;若环湖公路内侧全部实现退耕还林或还草,面源总磷负荷将减少60%;若同时实施减少磷肥施用量和环湖公路内退耕两项措施,面源总磷负荷将减少130%     

The characteristics of nitrate removal by the psychrotolerant denitrifying bacterium Acinetobacter johnonii DBP-3, isolated from a low-temperature eutrophic body of water

A psychrotolerant denitrifying bacterial strain, DBP-3, was isolated from a eutrophic body of water by low-temperature-oriented acclimation culture. Based on its morphologicalandbiochemicalcharacteristics and 16S rDNA gene sequence, the bacterium was identified as belonging to the genus Acinetobacter and closely related to A. johnonii. The satisfactory growth of DBP-3 was observed at 10–30°C and pH 7–9. Strain DBP-3 was able to utilize three types of carbon sources (sodium acetate > sodium citrate > glucose) to support growth and denitrification. DBP-3 grew faster, but with lower nitrate removal efficiency and higher nitrite accumulation, under aerobic conditions than under anoxic conditions. DBP-3 was extremely susceptible to tetracycline and rifampicine and less sensitive to ampicillin and penicillin. The growth of DBP-3 was significantly affected by Hg (II), Cr (VI), Pb (II), Cd (II), and As (III) at 0.32, 0.63, 1.25, 2.5, and 25.0 mg L^?1, respectively. Interestingly, chromium (VI) significantly promoted DBP-3 growth at concentrations lower than 0.32 mg L^?1. These data may be helpful to support the use of strain DBP-3 in the purification of eutrophic water bodies at low temperatures.     

Differential Effects of Legume Species on the Recovery of Soil Microbial Communities, and Carbon and Nitrogen Contents, in Abandoned Fields of the Loess Plateau, China

Plant–soil interactions are known to influence a wide range of ecosystem-level functions. Moreover, the recovery of these functions is of importance for the successful restoration of soils that have been degraded through intensive and/or inappropriate land use. Here, we assessed the effect of planting treatments commonly used to accelerate rates of grassland restoration, namely introduction of different legume species Medicago sativa, Astragalus adsurgens, Melilotus suaveolens, on the recovery of soil microbial communities and carbon and nitrogen contents in abandoned fields of the Loess Plateau, China. The results showed effects were species-specific, and either positive, neutral or negative depending on the measure and time-scale. All legumes increased basal respiration and metabolic quotient and had a positive effect on activity and functional diversity of the soil microbial community, measured using Biolog EcoPlate. However, soil under Astragalus adsurgens had the highest activity and functional diversity relative to the other treatments. Soil carbon and nitrogen content and microbial biomass were effectively restored in 3–5?years by introducing Medicago sativa and Astragalus adsurgens into early abandoned fields. Soil carbon and nitrogen content were retarded in 3–5?years and microbial biomass was retarded in the fifth year by introducing Melilotus suaveolens. Overall, the restoration practices of planting legumes can significantly affect soil carbon and nitrogen contents, and the biomass, activity, and functional diversity of soil microbial community. Therefore, we propose certain legume species could be used to accelerate ecological restoration of degraded soils, hence assist in the protection and preservation of the environment.