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Comparison of four test methods for toxicity evaluation of typical toxicants in petrochemical wastewater on activated sludge

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SCIENCE OF The TOTAL ENVIRONMENT 2019年 685卷 273-279页

作者： Yuan, Ye Yu, Yin Xi, Hongbo Zhou, Yuexi he, xuwen China Univ Min & Technol Coll Chem & Environm Engn Beijing 100083 Peoples R China Chinese Res Inst Environm Sci State Key Lab Environm Criteria & Risk Assessment Beijing 100012 Peoples R China

The shock impact of toxic pollutants in petrochemical wastewater on the activated sludge in biological treatment system is a key factor restricting the treatment efficiency. It is necessary to evaluate the toxicity of these pollutants by appropriate methods. In this study, four test methods were used to evaluate the toxicity of characteristic organic pollutants in petrochemical wastewater including 2,4-dichlorophenol, formaldehyde and pyridine, as well as one frequently-used reference toxicant 3,5-dichlorophenol. The sensitivity, accuracy and response time were compared among these methods: the oxygen consumption rate inhibition method (OCRIM), the dehydrogenase activity inhibition method (DAIM), the nitrification rate inhibition method (NRIM) and the growth rate inhibition method (GRIM). Principal component analysis was used to evaluate the correlation among the results of different methods. The OCRIM was comprehensively outstanding with the highest correlation between concentration and inhibition ratio (R-2 values were all higher than 0.9854), good sensitivity, best accuracy (error value of the effective concentrations below 0.15 mg/l) and fastest response (<40 min). The sensitivity of the NRIM was found to be the highest in this study (10% effective inhibition concentration (EC50) value of 3,5-dichlorophenol was only 0.03 mg/l). Therefore, combined tests of OCRIM and NRIM were suggested. (C) 2019 Elsevier B.V. All rights reserved.

关键词： Petrochemical wastewater Characteristic organic pollutant Activated sludge Principal component analysis Oxygen consumption rate inhibition method Nitrification rate inhibition method

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管道微絮凝-超滤工艺处理常规矿井水试验研究

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煤炭工程 2023年第6期55卷 20-24页

作者：李福勤高珊珊薛甜丽豆硕超何绪文河北工程大学能源与环境工程学院河北邯郸056038 河北省水污染控制与水生态修复技术创新中心河北邯郸056038 中国矿业大学(北京)化学与环境工程学院北京100083

针对现有矿井水处理技术存在投药量大、处理时间长、出水水质不稳定的问题,对常规矿井水进行管道微絮凝-超滤工艺试验研究。结果表明,管道微絮凝-超滤工艺处理矿井水性能良好,出水浊度均在0.07 NTU以下,去除颗粒物主要依靠超滤膜的筛分... 详细信息

针对现有矿井水处理技术存在投药量大、处理时间长、出水水质不稳定的问题,对常规矿井水进行管道微絮凝-超滤工艺试验研究。结果表明,管道微絮凝-超滤工艺处理矿井水性能良好,出水浊度均在0.07 NTU以下,去除颗粒物主要依靠超滤膜的筛分作用,微絮凝混凝剂种类、加药量、管长、管径等对浊度的去除效果影响不大;随着投药量的增加,Zeta电位逐渐减小并接近零点,随着运行时间的进行膜比通量衰减程度逐渐减小;当投药量为6 mg/L膜比通量J/J_(0)值下降最小。随着管道长度的增加,膜比通量的下降速率逐渐缓慢,管长在20~30 m,对应反应时间约20~30 s,较合适。流速对反应效果和超滤影响较大,流速在0.9 m/s左右较佳。随着运行压力的增大,产水率增大,膜比通量呈降低趋势。物理污染(颗粒堵塞)是矿井水对超滤膜污染的主要原因,最佳清洗方式为水力冲洗;微絮凝器管径4 mm,管长20 m,PAC投加6 mg/L,超滤跨膜压差为0.18 MPa时,过滤30 min膜比通量J/J_(0)为0.815,产水率为93.8%。

关键词：微絮凝超滤聚瓷膜矿井水膜通量

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横波检测圆柱内部不同角度缺陷的数值模拟

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应用激光 2023年第8期43卷 122-130页

作者：贺旭文郭华玲郑宾刘辉崔缙贾庸斌中北大学电气与控制工程学院山西太原030051

针对小口径金属圆柱内部不同角度缺陷的检测,通过有限元方法对铝圆柱中横波的传播特性进行研究。通过横波方向性的研究确定横波的能量范围,在横波的主要能量范围设置内部不同角度的人工矩形缺陷,通过B-scan的方法对PRS波(与缺陷作用的... 详细信息

针对小口径金属圆柱内部不同角度缺陷的检测,通过有限元方法对铝圆柱中横波的传播特性进行研究。通过横波方向性的研究确定横波的能量范围,在横波的主要能量范围设置内部不同角度的人工矩形缺陷,通过B-scan的方法对PRS波(与缺陷作用的一次反射横波)的传播特性进行研究。通过对PRS波出现的扫查角度范围进行统计研究,确定PRS波的最佳探测角β(扫查角度范围内PRS波幅值最大的扫查角度)。根据扫查角度范围内最大幅值PRS波的到达时间与缺陷角度α关系对α角进行了反演,α角为30°时误差最大,误差为0.025,其他缺陷角度下误差均小于0.02。利用PRS波的扫查角度范围和最佳探测角β完成不同α角下PRS波的可视化,提出一种通过提取能量点评估α角的方法。以上研究结果为激光超声检测柱状材料内部缺陷提供了一定的参考。

关键词：激光超声横波柱状材料内部缺陷角度数值模拟

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A review of clay based photocatalysts: Role of phyllosilicate mineral in interfacial assembly, microstructure control and performance regulation

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CheMOSPheRE 2021年 273卷 129723-129723页

作者： Li, Chunquan Zhu, Ningyuan Yang, Shanshan he, xuwen Zheng, Shuilin Sun, Zhiming Dionysiou, Dionysios D. China Univ Min & Technol Beijing Sch Chem & Environm Engn Beijing 100083 Peoples R China Chinese Acad Sci Inst Soil Sci State Key Lab Soil & Sustainable Agr Zigui Ecol Stn Three Gorges Dam Project 71 East Beijing Rd Nanjing 210008 Peoples R China Peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China Univ Cincinnati Dept Chem & Environm Engn DCEE Cincinnati OH 45221 USA

Over the past decades, inspired by the outstanding properties of clay minerals such as abundance, low-cost, environmental benignity, high stability, and regularly arranged silica-alumina framework, researchers put much efforts on the interface assembly and surface modification of natural minerals with bare photocatalysts, i.e. TiO2, g-C3N4, ZnO, MoS2, etc. The clay-based hybrid photocatalysts have resulted in a rich database for their tailor-designed microstructures, characterizations, and environmental-related applications. Therefore, in this study, we took a brief introduction of three representative minerals, i.e. kaolinite, montmorillonite and rectorite, and discussed their basic merits in photocatalysis applications. After that, we summarized the recent advances in construction of stable visible-light driven photocatalysts based on these minerals. The structure-activity relationships between the properties of clay types, pore structure, distribution/dispersion and light absorption, carrier separation efficiency as well as redox performance were illustrated in detail. Such representative information would provide theoretical basis and scientific support for the application of clay based photocatalysts. Finally, we pointed out the major challenges and future directions at the end of this review. Undoubtedly, control and preparation of novel photocatalysts based on clays will continue to witness many breakthroughs in the arena of solar-driven technologies. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Clay mineral Composite photocatalysts Interface assembly Surface modification Structure-activity relationship

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分子动力学模拟阴离子/两性离子表面活性剂在油-水界面的分子行为及协同效应

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石油学报（石油加工） 2021年第4期37卷 831-839页

作者：吴姁夏瑜苑莲花员润何绪文中国矿业大学(北京)化学与环境工程学院北京100083

采用分子动力学模拟方法研究了表面活性剂十二烷基硫酸钠(SDS)/十二烷基磺丙基甜菜碱(SB12-3)混合体系在油-水界面的聚集行为以及SDS与SB12-3的协同作用。通过密度分布、界面厚度、界面形成能来分析油-水界面性质,当n(SDS)/n(SB12-3)=1/... 详细信息

采用分子动力学模拟方法研究了表面活性剂十二烷基硫酸钠(SDS)/十二烷基磺丙基甜菜碱(SB12-3)混合体系在油-水界面的聚集行为以及SDS与SB12-3的协同作用。通过密度分布、界面厚度、界面形成能来分析油-水界面性质,当n(SDS)/n(SB12-3)=1/1时,协同效应达到最大,即混合体系的界面形成能(E_(IF))达到-640.959 kJ/mol。通过亲水基团的径向分布函数和氢键数目研究了SDS和SB12-3的亲水效应,发现SB12-3的亲水基团与水分子优先形成氢键,且形成氢键数目(12.555)大于SDS与水之间的氢键数目(8.968),SB12-3的亲水性更好;通过表面活性剂头基与尾链之间的夹角和疏水尾链序参数研究了2种表面活性剂的疏水性能,发现SDS烃链在油相中夹角(114.368°)大于SB12-3在油相中角度(111.903°),证明SDS拉伸程度好,表现出良好的疏水性能,2种表面活性剂的协同作用良好。

关键词：分子动力学模拟油-水界面十二烷基硫酸钠十二烷基磺丙基甜菜碱

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Glucose Addition Enhanced the Advanced Treatment of Coking Wastewater

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WATER 2021年第23期13卷 3365页

作者： Li, Na Xia, Yu he, xuwen Li, Weijia Yuan, Lianhua Wu, Xu Qin, Yihe Yuan, Run Gong, Xun China Univ Min & Technol Sch Chem & Environm Engn Beijing 100083 Peoples R China

Biological processes have high removal efficiencies and low operational costs, but the secondary effluent of coking wastewater (CWW), even at a low concentration, is difficult for microorganisms to degrade directly. In this study, glucose was used as a carbon source and co-metabolic substrate for microbial acclimation in order to enhance the advanced treatment of coking wastewater (CWW). The removal performance of the pollutants, especially recalcitrant compounds, was studied and the changes in the microbial community structure after activated sludge acclimation were analyzed. The effect of glucose addition on the secondary biochemical effluent of coking wastewater (SBECW) treatment by the acclimated sludge was further studied by a comparison between the performance of two parallel reactors seeded with the acclimated sludge. Our results showed that the concentrations of chemical oxygen demand (COD), total organic carbon (TOC), and UV absorption at 254 nm (UV254) of the wastewater decreased in the acclimation process. Refractory organic matter, such as polycyclic aromatic hydrocarbons and nitrogen-containing heterocyclics, in the SBECW was effectively degraded by the acclimated sludge. High-throughput sequencing revealed that microbes with a strong ability to degrade recalcitrant compounds were enriched after acclimation, such as Thauera (8.91%), Pseudomonas (3.35%), and Blastocatella (10.76%). Seeded with the acclimated sludge, the reactor with the glucose addition showed higher COD removal efficiencies than the control system without glucose addition (p < 0.05). Collectively, glucose addition enhanced the advanced treatment of coking wastewater (CWW).

关键词： microbial acclimation coking wastewater advanced treatment recalcitrant compounds microbial diversity

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Effective mineralization of quinoline and bio-treated coking wastewater by catalytic ozonation using CuFe2O4/Sepiolite catalyst: Efficiency and mechanism

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CheMOSPheRE 2019年 227卷 647-656页

作者： Liu, Dan Wang, Chunrong Song, Yifan Wei, Yanhong he, Lei Lan, Bangrui he, xuwen Wang, Jianbing China Univ Min & Technol Beijing Sch Chem & Environm Engn Beijing 100083 Peoples R China

In this study, CuFe2O4 nanocomposite loaded on natural sepiolite (CuFe2O4/SEP) was prepared by the citrate sol-gel method. CuFe2O4/SEP was characterized by X-ray diffraction, Brunauer-Emmett-Teller adsorption analysis, scanning electron microscopy, and energy dispersive spectroscopy. The CuFe2O4/SEP composite was stable and showed an excellent catalytic activity for ozonation. The efficiency of quinoline mineralization in the catalytic ozonation with CuFe2O4/SEP was 90.3%, and this value was 5.4 times higher than that of the uncatalyzed ozonation (16.8%). The quinoline mineralization followed a pseudo first-order kinetics with all the catalysts. The rate constant for the mineralization of quinoline by ozonation in the presence of CuFe2O4/SEP was 0.0885 min(-1), which was 16.7 times higher than that in ozone alone (0.0053 min(-1) ). Radical scavenging tests revealed that hydroxyl radical (center dot OH) and superoxide radical (center dot O-2(-)) were the reactive oxygen species (ROS) in the quinoline degradation. In the presence of CuFe2O4/SEP, ozone and hydrogen peroxide were rapidly converted into the ROS. Although neutral and alkaline pH were more beneficial for the quinoline mineralization, CuFe2O4/SEP exhibited significant catalytic activity even under acidic conditions. Meanwhile, five-cycle successive tests suggested that CuFe2O4/SEP was recyclable and hence, stable. Furthermore, the feasibility of the catalytic ozonation for the treatment of biologically treated coking wastewater was evaluated. The catalytic ozonation resulted in 57.81% total organic carbon removal efficiency at 60 min, which was 2.9 times higher than that in the uncatalyzed ozonation (19.99%). (C) 2019 Elsevier Ltd. All rights reserved.

关键词： CuFe2O4/Sepiolite Catalytic ozonation Quinoline Mechanism Biologically treated coking wastewater

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行政规章对合同效力的影响:正当性与界限

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法治社会 2021年第1期 37-47页

作者：夏昊晗何旭雯中南财经政法大学中南财经政法大学中南司法案例研究中心

行政规章并不属于影响合同效力的法律位阶范畴,但司法实践中依行政规章将合同归于无效的案件不在少数。行政规章对合同效力的影响主要体现在行为禁止型、资格许可型案件中,法院往往以“损害社会公共利益”“行政规章系相关法律授权”以... 详细信息

行政规章并不属于影响合同效力的法律位阶范畴,但司法实践中依行政规章将合同归于无效的案件不在少数。行政规章对合同效力的影响主要体现在行为禁止型、资格许可型案件中,法院往往以“损害社会公共利益”“行政规章系相关法律授权”以及“违反行政规章资格许可规定”等路径认定合同无效。行政规章影响合同效力具有一定正当性,亦有其必要性。但由于缺乏统一标准和法律规制,认定违反行政规章的合同无效之路径有架空《民法典》第一百五十三条第一款规定之嫌,亦存在社会公共利益界定不统一和公法过度干预私法自治等弊病。为防止公法过度干预私法自治,同时为了保障裁判的统一性及司法公正,以各种裁判路径将违反行政规章的合同归于无效,须受到严格的法律规制。

关键词：行政规章合同效力社会公共利益法律规制

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Treatment of coking wastewater using oxic-anoxic-oxic process followed by coagulation and ozonation

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Carbon Resources Conversion 2019年第2期2卷 151-156页

作者： Jianbing Wang Yuxian Ji Fengyuan Zhang Dongliang Wang xuwen he Chunrong Wang School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

An oxic-anoxic-oxic(O-A-O)system followed by coagulation and ozonation processes was used to study the treatment of coking *** the O-A-O process,the removals of NH4+-N,total nitrogen and COD were 91.5-93.3%,91.3-92.6%and 89.1-93.8%,respectively when employing hydraulic residence times of 60 h for the biochemical *** removal of NH4+-N was obtained due to the placement of an aerobic tank in front of A-O system which can mitigate the inhibitory effect of toxic compounds in coking wastewater on nitrifying *** of methanol into the anoxic reactor greatly increased the removal of total nitrogen,indicating that denitrifiers can hardly use organic compounds in coking wastewater as carbon source for *** values of the effluent from the O-A-O system were still higher than 260 mg/L even with a prolonged time of 160 h mainly due to the high refractory properties of residual compounds in the *** subsequent coagulation and ozonation processes resulted in the COD removal of 91.5%-93.3%and reduced the relative abundance of large molecular weight(MW)organics(>1 kDa)from 55.8%to 20.93%with the ozone,PAC and PAM dosages of 100,150 and 4 mg/L *** these conditions,the COD value and concentration of polycyclic aromatic hydrocarbons in the final effluent were less than 80 and 0.05 mg/L,respectively,which meet the requirement of the Chinese emission *** results indicate that the combined technology of O-A-O process,coagulation and ozonation is a reliable way for the treatment of coking wastewater.

关键词： Coking wastewater Activated sludge process Coagulation Ozonation Nitrification-denitrification

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Putative functions and co-occurrence patterns of the microbial communities in natural and engineered ecosystems

Research Square

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Research Square 2021年

作者： Xia, Yu Li, Na Chen, Yiyun Li, Weijia he, xuwen Xu, heng Wang, Jianbing China University of Mining and Technology Beijing China

Understanding functions and co-occurrence patterns of microbial communities in various ecosystems enriches the knowledge on ecosystem characteristics and microbial ecology. However, such analyses have rarely been reported. herein, functions and inter-taxa correlations of microbial communities in a set of natural environments (farmland (SA), forest soil (SB) and Caspian Sea sediments (CSS)) and engineered ecosystems (wastewater treatment plants (FW, WA and WB) and anaerobic digesters (AD)) were studied based on FAPROTAX and network analyses, respectively, by a collection of 115 samples from seven published 16S rRNA gene datasets generated by high-throughput sequencing. The results show that chemoheterotrophy related populations were the most abundant in almost all the communities. Their relative abundances (RAs) in the AD systems were the highest (43.7%±4.2%), followed by those of the soil environments (40.2%±1.9% in SA and 36.4%±2.0% in SB). For each ecosystem, the indicative community and overall community showed differentiations in several function categories. For example, the SA and SB indicative communities showed higher RAs in aerobic chemoheterotrophy, the CSS indicative community showed higher RAs in sulfate respiration, the AD indicative community showed higher RAs in fermentation, and the WB indicative community included higher RAs of predatory/exoparasitic bacteria. Three molecular ecological networks of the communities from the AD, WB and SB datasets were constructed, respectively. The WB network showed the highest proportion of negative correlations (70.4%), possibly attributed to the environmental pressure which aggravated microbial competition. The positively correlated taxa showed lower phylogenetic distances than the negatively correlated taxa on average in each network. © 2021, CC BY.

关键词： Ecosystems

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