郑州市少数民族运动会期间O3及VOCs污染特征的演变和评估

基于近地面观测的常规污染六参数、气象数据和在线VOCs数据,以臭氧及其前体物VOCs为研究重点,评估了民运会期间采取的污染管控措施对郑州市空气质量的影响.结果表明,2019年民运会管控期间污染物六参数相较上年同期均呈现降低趋势,其中PM_2.5和PM₁₀浓度分别降低了16.2%和25.1%,但是臭氧日最大8 h浓度均值的降幅仅为3.7%,且臭氧为首要污染物的天数超过90%.就臭氧前体物VOCs而言,民运会期间PAMS浓度（26.21×10^-9）低于历史同期;利用PMF模型解析出6个因子,依次为机动车尾气（28%）、LPG（21%）、燃烧（16%）、工业（15%）、溶剂（15%）和植物排放（5%）;空气保障期间,对燃烧源和工业源的管控较为明显.     

间歇梯度曝气的生活污水好氧颗粒污泥脱氮除磷

本研究设置了3个SBR反应器R1、R2和R3,分别采用(A/O)_3-SBR梯度曝气、(A/O)_3-SBR恒定曝气和传统(A/O)-SBR方式运行,以实际城市生活污水为进水基质,探讨了不同曝气方式下的营养物去除性能和好氧颗粒污泥特性,为低强度城市污水的碳源合理利用提供合理的方式.由实验结果可知,R1、R2和R3中颗粒在稳定时期对COD的平均去除率分别为88.68%、 89.05%和88.96%,对TN的平均去除率分别为76.97%、 71.99%和64.92%,对TP的平均去除率分别为96.28%、 85.05%和78.97%,且反硝化聚磷菌占聚磷菌的比例分别为25.52%、 19.60%和12.77%.结果表明,厌氧、好氧和缺氧交替的运行方式更有利于反硝化聚磷菌(DPAOs)的富集,且梯度曝气较恒定曝气方式富集更多,这对碳源不足的低强度城市生活污水处理有重要意义;同时R1中曝气段溶解氧逐级降低,提高了颗粒同步硝化反硝化率和降低了能耗,有利于总氮(TN)的高效去除. 3组反应器在运行后期颗粒粒径分别为727.368、 815.072和895.041μm,且通过对颗粒进行显微观察可以看出, R2和R3中颗粒不如R1中密实.此外,R1、R2和R3运行后期PN/PS值分别为6.31、 5.63和4.83,颗粒稳定时期EPS含量(以VSS计)分别为103.97、 92.22和76.98 mg·g~(-1),表明间歇梯度曝气的方式有利于刺激EPS的分泌,尤其是PN的分泌,使PN/PS值较高,细胞疏水性增强,颗粒密实稳定.     

郑州市冬季VOCs污染特征、来源及健康风险评估

采用GC5000在线气相色谱仪于2018年1月8—26日对郑州市城区进行大气环境挥发性有机化合物（VOCs）监测,开展污染特征分析、来源解析和苯系物（BTEX）健康风险评估.结果表明,监测期间郑州市城区TVOC平均浓度为64×10^-9,污染期时段平均浓度为84×10^-9,约是非污染时段的2倍;组分构成显示烷烃占比最大,其次是烯炔烃和芳香烃;源解析结果显示,VOCs主要来源是液化石油气/天然气（25%）、机动车尾气（24%）、燃烧（21%）、工业排放（16%）和溶剂使用（14%）;监测期间苯系物非致癌风险危害值（HQ）在美国环保署规定的安全范围内,苯的致癌风险（R）为2.2×10^-6,超过了美国环保署规定的安全阈值（1.0×10^-6）.对成年人存在致癌风险,需要引起关注.     

污水处理厂SNAD工艺小试

在污水处理厂室外,以A/O除磷工艺出水为基质,启动全程自养脱氮(CANON)生物滤柱反应器.反应器启动成功后,进水中投加葡萄糖作为有机碳源,启动同步短程硝化、厌氧氨氧化耦合反硝化(SNAD)工艺,研究SNAD生物滤柱处理城市生活污水的效果.结果表明,第119～128 d,CANON工艺氨氮去除率大于95%,最大出水总氮浓度为13. 0 mg·L~(-1),超过了北京市地标一级A排放标准.第129 d在进水中投加葡萄糖30 mg·L~(-1)启动SNAD工艺,第133～187 d时SNAD工艺总氮去除率在85%左右,出水总氮浓度为5. 5～7. 3 mg·L~(-1).第195d观察到滤柱出现堵塞现象,在第196 d对反应器进行反冲洗,反冲洗后的30d期间,反应器总氮去除率大于85%,出水总氮浓度维持在6. 2～7. 2 mg·L~(-1).与CANON工艺相比,SNAD工艺提高了总氮去除率,将出水总氮浓度降低了6 mg·L~(-1),使出水氨氮和总氮浓度达到北京市地标一级A标准.     

水质生物毒性检测仪在环境治理中的应用研究

水中存在的多种有毒生物严重影响水体质量,对水质生物的毒性进行检测,可有效提高环境治理效果。采用毒性检测仪对水质生物毒性进行检测,通过分析水质生物毒性检测仪的光电探测器、分压器等硬件结构的工作原理,完成对水质生物毒性的检测。实验结果表明,采用水质生物毒性检测仪检测方法与传统检测方法得到的检测结果相差较小,其具有的便于携带、操作简单和实验周期短等优点,可有效的应用到环境治理中,为环境治理提供较大帮助。     

不同来源废水中TOC与COD相关性研究

对纺织染整、化工、制药、食品加工各行业生产废水及城镇污水厂处理设施出水中的TOC(自动仪器监测)与COD(实验室手工分析)测定值进行回归分析,并检验一元线性回归方程的显著性和有效性。结果表明,各行业生产废水中TOC与COD值均存在非常显著的相关性,且废水组成成分越单一稳定,其相关性越好,同行业废水中TOC与COD回归方程的斜率b较为接近。利用TOC自动在线监测值换算所得的COD值,准确性和稳定性高,能满足水质实时连续监测的需要。     

地块重金属测定及生态环境风险评价研究

对某地块土壤样品进行采集、测试,利用单项污染指数法、内梅罗综合污染指数法、潜在生态危害指数对测定结果进行评价。铜、铅、锌、镉、汞、砷的浓度分别为21.7 mg/kg、27.8 mg/kg、66.9 mg/kg、0.125 mg/kg、0.070 mg/kg、17.7 mg/kg,达到《土壤环境质量标准》(GB 15618-1995)中的表1二级标准。单因子污染指数法计算结果显示监测地块土壤未受到污染;内梅罗综合污染指数均小于0.7,污染等级为安全、污染水平为清洁;监测的6种重金属的潜在生态危害系数均小于4,潜在生态危害指数计算结果小于150,表明有一定的轻微生态危害。     

实际重力流排水管道中微生物群落对管道的腐蚀影响

通过在实际重力流排水管道中选取10个典型的腐蚀区域作为研究对象,通过对排水管道对应腐蚀区域的生物膜和水体进行采样,探究实际排水管道不同空间位置上微生物群落分布的差异性以及水质因素对微生物群落多样性分布影响.采用高通量测序方法反映腐蚀区域微生物群落的多样性.结果表明,在排水管道中10个典型腐蚀区域中的微生物群落分布结构基本相似,在门水平上主要是变形菌占绝对优势,其次是放线菌门,在纲水平上主要是a-变形菌纲,其次是β-变形菌纲两者相对含量之和占到43.56%,在属水平上的硫酸盐还原菌对管道具有严重的局部腐蚀,包含有Desulforhabdus,Desulfuromonas,Desulfobacter.RDA环境影响因子研究发现,在门水平上硫化氢、溶解氧与微生物群落存在一定的相关性,在纲水平上与微生物群落存在相关性的主要是铵根离子、pH值和COD.     

Variations in concentrations and bioavailability of heavy metals in rivers caused by water conservancy projects: Insights from water regulation of the Xiaolangdi Reservoir in the Yellow River

Water regulation of the Xiaolangdi Reservoir of the Yellow River was chosen as a case to investigate variations in concentrations and bioavailability of heavy metals caused by water conservancy projects in rivers. Water and suspended sediment (SPS) samples were collected at downstream sampling sites along the river during this period. Concentrations and speciation of Zn, Cr, Cu, Ni, and Pb in water and SPS samples were analyzed, and their bioaccumulation was studied with Daphnia magna. This study indicated that the exchangeable and carbonate-bound fractions of heavy metals in SPS decreased along the studied stretch, and the dissolved heavy metal concentrations increased along the river with 1.6–15 folds. This is because sediment resuspension increased along the river during water regulation, giving rise to the increase of heavy metal release from SPS. The dissolved Zn, Cu, Ni, and Pb concentrations were significantly positively correlated with SPS concentrations, and their increase along the river was greater than Cr. The body burdens of heavy metals in D. magna exposed into samples collected from the reservoir outlet were 1.3–3.0 times lower than those from downstream stations, suggesting that the heavy metal bioavailability increased during water regulation. This should be considered in the reservoir operation.     

Degradation of sulfonamides and formation of trihalomethanes by chlorination after pre-oxidation with Fe(VI)

Sulfonamides are used in human therapy, animal husbandry and agriculture but are not easily biodegradable, and are often detected in surface water. Sulfamethazine (SMZ) and sulfadiazine (SDZ) are two widely used sulfonamide antibiotics that are used heavily in agriculture. In this study, they were degraded in an aqueous system by chlorination after pre-oxidation with ferrate(VI) (Fe^VIO₄^2 ?, Fe(VI)), an environmentally friendly oxidation technique that has been shown to be effective in degrading various organics. The kinetics of the degradation were determined as a function of Fe(VI) (0–1.5 mg/L), free chlorine (0–1.8 mg/L) and temperature (15–35°C). According to the experimental results, SMZ chlorination followed second-order kinetics with increasing Fe(VI) dosage, and the effect of the initial free chlorine concentration on the reaction kinetics with pre-oxidation by Fe(VI) fitted a pseudo-first order model. The rate constants of SDZ and SMZ chlorination at different temperatures were related to the Arrhenius equation. Fe(VI) could reduce the levels of THMs formed and the toxicity of the sulfonamide degradation systems with Fe(VI) doses of 0.5–1.5 mg/L, which provides a reference for ensuring water quality in drinking water systems.