新能源集中接入下的宁夏电网无功规划研究

针对新能源并网容量不断增加,大规模新能源接入电网时无功电压控制困难的问题,通过研究在新能源大出力方式下系统电压水平、电压波动及严重故障时电压失稳情况,提出了动态无功补偿、低压无功补偿配置方案。研究结果表明提出的无功配置方案适用于宁夏电网新能源场站和新能源汇集站的动态无功补偿,已纳入宁夏“十三五”电网滚动规划,对于保障宁夏电网安全稳定运行具有重要意义。     

Chemical additives affect sulfate reducing bacteria biofilm properties adsorbed on stainless steel 316L surface in circulating cooling water system

This paper studied the biofilm properties and corrosion behavior of sulfate reducing bacteria (SRB) on stainless steel 316L (SS316L) surface in circulating cooling water system with and without additives including hydroxy ethyl fork phosphonic acid (HEDP), dodecyl dimethyl benzyl ammonium chlotide (1227) and NaClO. Biochemical technique, electrochemical technology, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used. The results show that the extracellular polymeric substance (EPS) in biofilm attached on the SS316L surface mainly contain proteins and polysaccharides, the contents are 98 ug·cm^-2 and 635ug·cm^-2, respectively. The polysaccharides were cut by 1227 about 80%, while 55% by NaClO. The proteins were reduced by NaClO about 53%, while only 30% by 1227. The potentiodynamic polarization shows that the corrosion potential of SS316L was enhanced from -0.495 V to -0.390 V by the chemical additives, delaying the occurrence of the corrosion. And the corrosion rate was also reduced from 5.19 × 10^-3 mm·a^-1 to 2.42 × 10^-3 mm·a^-1. But NaClO still caused pitting corrosion after sterilizing the bacteria, while 1227 can form a protective film on the surface of SS316L. Though HEDP contribute to the bacteria activity, it can enhance the breakdown potential. XPS results confirmed that 1227 can change the value of C:O in the biofilm attached on metal surface, and NaClO can eliminate the existence of amidogen. This study would provide some recommendations for the selection of chemical additives in the thermal power plant.

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Present status of recycling waste mobile phones in China: a review

A large number of waste mobile phones have already been generated and are being generated. Various countries around the world have all been positively exploring the way of recycling and reuse when facing such a large amount of waste mobile phones. In some countries, processing waste mobile phones has been forming a complete industrial chain, which can not only recycle waste mobile phones to reduce their negative influence on the environment but also turn waste into treasure to acquire economic benefits dramatically. However, the situation of recycling waste mobile phones in China is not going well. Waste mobile phones are not formally covered by existing regulations and policies for the waste electric and electronic equipment in China. In order to explore an appropriate system to recover waste mobile phones, the mobile phone production and the amount of waste mobile phones are introduced in this paper, and status of waste mobile phones recycling is described; then, the disposal technology of electronic waste that would be most likely to be used for processing of electronic waste in industrial applications in the near future is reviewed. Finally, rationalization proposals are put forward based on the current recovery status of waste mobile phones for the purpose of promoting the development of recycling waste mobile phones in developing countries with a special emphasis on China.     

Effect of acute exposure to PFOA on mouse liver cells in vivo and in vitro

Increasingly, epidemiological evidences indicate chemosynthetic perfluorooctanoic acid (PFOA), an environmental pollutant, induces potential adverse effect on human health after long-term exposure. However, less study has been performed for assessment of acute effect of PFOA exposure on metabolic homeostasis. In experimental designs, PFOA-exposed liver cells in vivo and in vitro were used to discuss underlying mechanism related to PFOA-induced metabolic dysfunction. In serological tests, PFOA-exposed mice showed increased treads of liver functional enzymes in alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (T-BIL), trypsinase, low density lipoprotein-cholesterol (LDL-C), and insulin, while blood glucose, high density lipoprotein-cholesterol (HDL-C), and glucagon levels were reduced. In histocytological observations, PFOA-exposed liver showed visible cytoplasmic vesicles, and intact pancreatic islets were observed in PFOA-exposed pancreas. Additionally, increased insulin-positive cells and reduced glucagon-positive cells were detected in PFOA-exposed islets. As shown in immunoassays, PFOA-exposed liver resulted in elevations of cluster of differentiation 36 (CD36)-labeled cells and CD36 protein. In mouse liver cell study, PFOA-exposed cells showed increased cell apoptotic count, and increased phosphorylated levels of Bcl-2 and Bad in the cells. Furthermore, PFOA-exposed liver cells exhibited elevations of CD36-labeled cells and CD36 protein. Taken together, the present data demonstrate that acute exposure to PFOA-impaired liver function is associated with inducting CD36 expression and apoptosis, as well as disrupting key hormones in the pancreas.     

Microbial community composition and electricity generation in cattle manure slurry treatment using microbial fuel cells: effects of inoculum addition

Environmental Science and Pollution Research - Microbial fuel cell (MFC) is a sustainable technology to treat cattle manure slurry (CMS) for converting chemical energy to bioelectricity. In this...     

不同流量分配比对多级A/O工艺去除有机物及脱氮的影响

采用三级A/O工艺分段进水工艺处理低碳源生活污水,考察了进水流量分配比对系统去除有机物、硝化反硝化能力以及去除TN的影响。通过对水质指标沿程监测结果表明,不同流量分配比(4∶3∶3,5∶3∶2,6∶3∶1)对系统去除有机物及硝化效率影响不大,出水COD、氨氮分别均在30 mg/L、1 mg/L以下。但反硝化效果受流量分配比的影响较大,在流量比为5∶3∶2时,有效利用原水中碳源进行反硝化,反硝化效果最好。在流量比为5∶3∶2的情况下,TN出水为5.7 mg/L去除率为82.9%,优于流量分配比为6∶3∶1和4∶3∶3时的脱氮效果。总体而言,分段进水工艺在对碳源的有效利用及能耗节省方面优于单点进水。     

超滤膜深度处理染整废水的膜污染机理

实验采用不同规格和材料的超滤膜进行染整二级尾水分离实验,对超滤膜污染机理及影响因素进行了分析。实验采用红外光谱分析了聚醚(PES)膜、聚砜(PSF)膜和聚醚酰亚胺(PEI)膜3种超滤膜材料,对比了污染前后膜面的接触角以及不同切割分子量对膜通量及出水水质的影响,并利用线性化的Herman堵塞模型拟合了不同分子量超滤膜的堵塞模型,初步探讨了超滤膜的污染机理。实验结果表明,膜材料表面亲水性基团的多少与初始膜通量大小成正比,出水COD值随超滤膜切割分子量减小而减小。切割分子量同为2 000 Da的3种超滤膜中,PES膜的处理效果最佳,出水COD平均值为47.81 mg/L;PEI膜通量最高,平衡通量可达50 L/(m2.h);切割分子量为1 000、10 000的超滤膜堵塞机理符合滤饼过滤模型,100 000的超滤膜堵塞机理更接近于完全堵塞模型;1 000的聚醚砜材质膜(PES)更适合此类废水的深度处理。     

臭氧催化氧化工艺深度处理印染废水

采用正交实验对催化剂NiO/γ-A12O3的制备条件进行优化,并探讨臭氧催化氧化法对于印染废水的深度处理效能.结果表明,最优的催化剂制备条件为:浸渍液浓度为3％、浸渍时间为4h、灼烧温度为450℃、灼烧时间为3h.臭氧催化氧化反应15 min时,COD浓度由84.22 mg/L降低至50.00 mg/L以下;氨氮浓度由10.88 mg/L降低至5.01 mg/L;色度去除率达到69％,明显高于单纯臭氧氧化的反应效率.