磁性生物膜载体的规模化制备、表征和应用

利用机械力化学表面改性原理设计了卧式双旋搅拌混合反应设备,通过磁铁矿粉和适量浓硫酸的球磨混合反应制备得到磁性生物膜载体,其XRD、IR、SEM和BET表征分析结果表明,磁性生物膜载体表层生成了多羟基硫酸铁为主的活性组分.进而在膜生物反应器实验装置中投加磁性生物膜载体进行了中试实验,结果表明,磁性生物膜载体能与活性污泥中的微生物聚合形成稳定的菌胶团,活性污泥SV30从实验初期89％降到了稳定期的39％,此外,磁性生物膜载体还具有稳定膜生物反应池出水COD,强化脱氮除磷的能力.     

密相塔半干法烟气脱硫塔内加湿降温及其对脱硫效率的影响

为了实现密相塔半干法脱硫工艺的精确加湿进一步提高系统脱硫效率,利用推导出的传热传质计算方法,得到烟气温度降低和加水量的关系.结合3组密相塔半干法工程实际数据,发现理论计算值和实测值误差区间仅为2.9％ ～5.4％.通过选取河北某钢厂210 m2烧结烟气密相塔半干法脱硫项目实际在线检测数据,发现循环脱硫灰含湿量为3％的系统脱硫效率整体高于含湿量为5％和4％的样品,最大值达93.56％.通过粒度分析、扫描电镜、X射线衍射及差热-热重对2种不同含湿量的循环脱硫灰进行表征,结果表明,含湿量为3％的循环脱硫灰较含湿量为5％的样品粒径小、比表面积大,无团聚现象,物相分析还证实相对于含湿量为5％样品,其Ca(OH)2和结晶水含量少,几乎都是CaSO4和CaS03干态物质,因此脱硫反应进行彻底,脱硫效率较高.     

浸渍改性活性碳纤维吸附氮氧化物性能

为实现新风在通过空调进入室内前已被优化的目的,搭建了一套开式循环系统。通过对活性碳纤维进行浸渍改性,采用比表面测定、SEM观察、XPS分析、傅里叶变换红外谱图分析对改性前后活性碳纤维进行了表征;定量研究了室外氮氧化物初始浓度、温度和风速等环境因素对改性前后活性碳纤维吸附氮氧化物效率的影响。结果表明,改性对活性碳纤维表面活性官能团种类、含氧官能团数量、表面微观结构及比表面积等特性均有显著影响,提高了其对氮氧化物的吸附效率;室外初始浓度、风速、温度对改性前后活性碳纤维吸附氮氧化物效率的变化趋势基本一致;改性前后活性碳纤维对氮氧化物的吸附率随初始浓度的升高而逐渐降低,随过滤器处风速增大先升高后降低,随过滤器处温度的升高先升高后降低。改性后活性碳纤维对空气中氮氧化物的吸附率明显提高,可以将其应用于空调系统中。     

重捕剂SDTC的合成及其处理含铊废水的研究

以小分子胺类、二硫化碳和十二烷基苯磺酸钠(SDBS)为原料合成一种复配型重捕剂SDTC,用于处理烧结脱硫含铊废水。采用响应面法通过Box-Behnken(BBD)实验设计影响铊去除率的反应条件,对废水pH、SDTC投加量、反应时间和无机离子进行了优化分析,同时通过红外光谱和紫外光谱对SDTC及其与铊生成的螯合物(SDTC-Tl)结构进行表征。结果表明,二次多项式模型的回归系数R~2为0.982 8,模型对实验数据的拟合度高。采用响应面法优化得出处理1.20mg/L含铊废水的最佳条件并对其进行修正为:废水pH 9.00,SDTC投加量2.80g/L,反应时间25.0min,无机离子21.1g/L,该条件下铊去除率为99.89%,实验结果与模型预测值吻合。红外和紫外光谱分析结果表明,SDTC与铊会发生配位反应,生成的SDTC-Tl可较长时间放置,不易产生二次污染。     

Antimony smelting process generating solid wastes and dust：Characterization and leaching behaviors

A large amount of solid waste has been produced by the antimony smelting process in the＂World Capital of Antimony＂, Xikuangshan area in China. This study comprehensively investigated the physical and chemical characteristics of the various solid wastes, as well as the leaching behavior of the solid wastes, which included water-quenched slag,arsenic-alkali residue, desulfurized slag and blast furnace dust. These four types of waste were enriched in a variety of heavy metals and metalloids and more specifically with As and Sb levels up to 8.6 × 104 and 3.16 × 105mg/kg, respectively, in arsenic-alkali residue. For desulfurized slag and water-quenched slag, the leaching concentration of Sb significantly exceeded the acceptable limits during the leaching tests using the toxicity characteristic leaching procedure and the synthetic precipitation leaching procedure. In addition, As leaching in arsenic-alkali residue was extraordinarily hazardous, being three orders of magnitude higher than the regulatory level of As. According to the results of the extraction tests, all the tested wastes were classified as hazardous waste.     

Debromination of decabromodiphenyl ether by organo-montmorillonite-supported nanoscale zero-valent iron：Preparation, characterization and influence factors

An organo-montmorillonite-supported nanoscale zero-valent iron material(M-NZVI) was synthesized to degrade decabromodiphenyl ether(BDE-209). The results showed that nanoscale zero-valent iron had good dispersion on organo-montmorillonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30–90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased.     

Reduction and characterization of bioaerosols in a wastewater treatment station via ventilation

Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study,airborne microorganisms generated from a wastewater treatment station(WWTS) that uses an oxidation ditch process were diminished by ventilation.Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups,concentrations,size distributions,and species diversity of airborne microorganisms before and after ventilation. There were 3021 ± 537 CFU/m3 of airborne bacteria and 926 ± 132 CFU/m3 of airborne fungi present in the WWTS bioaerosol.Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after4 hr of air exchange. The highest removal(92.1% for airborne bacteria and 89.1% for fungi) was achieved for 0.65–1.1 μm sized particles. The bioaerosol particles over 4.7 μm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away,which led to the relatively easy reduction of bioaerosol particles0.65–1.1 μm and over 4.7 μm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.     

Characterization of extracellular polymeric substances in the biofilms of typical bacteria by the sulfur K-edge XANES spectroscopy

A combined approach of physicochemical extraction and sulfur K-edge X-ray absorption near-edge structure（XANES） spectroscopy was applied to characterize the extracellular polymeric substances（EPS） of typical bacterial biofilms in this study. Physicochemical analysis showed variation of the contents of DNA,polysaccharide and protein in different fractions of EPS in different mediums. The sulfur K-edge XANES analysis yielded a variety of spectra.Spectral fitting of the XANES spectra utilizing a large set of model compounds showed that there was more reduced sulfur in both LB-EPS（loosely bound EPS） and TB-EPS（tightly bound EPS） of all the biofilms in LB medium than in R2 A medium. More oxidized sulfur was identified in LB-EPS than that in TB-EPS,suggesting different niches and physiological heterogeneity in the biofilms. Our results suggested that the sulfur K-edge XANES can be a useful tool to analyze the sulfur speciation in EPS of biofilms.     

新型催化剂BiOI粉末的低温制备及其光催化性能研究

通过低温法制备Bi OI粉末,运用SEM、XRD和DRS对制备产物进行表征。结果显示Bi OI结晶度好、粒径小、比表面积大、可见光利用强。以甲基橙为主要目标物,对其在可见光下进行光催化降解研究。实验表明:在可见光下,p H=5.5,甲基橙初始浓度为20mg/L,Bi OI投加量为0.20g/L时,综合降解效果最好,210min光降解率可达80%;相同条件下,Bi OI降解直接黑、甲基紫、刚果红染料都有良好的效果,说明Bi OI拥有一定的应用前景。     

基于二值逻辑的复合绝缘子状态判别策略研究

复合绝缘子是架空输电线路上广泛使用的设备,它的老化会给电力系统的正常运行带来威胁。电力相关工作人员需要一种能够对复合绝缘子的运行状态进行判别的方法,帮助他们确定复合绝缘子是否满足运行要求,而对复合绝缘子的定性表征就成为一种优选的表征策略。将运行后的复合绝缘子分成"满足运行要求"和"不满足运行要求",使用二值逻辑回归模型,选取合适的特征量,建立了复合绝缘子状态表征体系。