两池轮流曝气活性污泥法处理城市污水的试验研究

提出一种新型活性污泥工艺--两池轮流曝气活性污泥法,试验研究了其对城市污水处理的效果及可行性.试验表明,两池轮流曝气活性污泥法处理城市污水对有机物和氨氮的去除效果明显.在进水COD浓度为402.18～413.06 mg/L,总氮为54.02～61.86 mg/L,氨氮为51.46～58.72 mg/L,总磷为2.43～3.51 mg/L时,该工艺对COD、总氮、氨氮和总磷的去除率分别为82.06%～88.11%、76.81%～81.36%、78.64%～85.87%和62.53%～70.26%,出水可达<污水综合排放标准>中的二级标准.本工艺具有良好的适用性,为城市污水处理提供了一条新的途径,为进一步研究提供了理论依据及思路.     

不同温度条件水解酸化-好氧工艺处理高矿化度采油废水

采用不同温度组合的水解酸化-好氧工艺对胜利油田某联合处理站经过"隔油-混凝-过滤"处理的高矿化度采油废水进行处理.结果表明:水解酸化反应器内的微生物能够适应高温(55℃)的环境,而好氧反应器中微生物的活性会受到高温较大的抑制;"高温水解酸化-中温好氧工艺"和"中温水解酸化-中温好氧工艺"可以使出水COD达到低于80 mg/L的外排要求,停留时间分别为15 h和7.5 h.采用水解酸化-好氧工艺处理高矿化度油田采油废水足可行的.     

“中老龄”垃圾渗滤液重金属和氨氮的厌氧毒性

通过厌氧毒性试验（ATA）研究了“中老龄”垃圾渗滤液的重金属和氨氮对厌氧微生物的毒性抑制作用。试验结果表明,“中老龄”垃圾渗滤液中的重金属和氨氮使厌氧污泥产甲烷活性分别下降14.4%和36.7%,4倍受试渗滤液重金属浓度或4 000 mg/L的氨氮浓度均可使污泥活性受到重度抑制。通过对不同浓度重金属和氨氮的厌氧毒性的关系进行回归分析,得出氨氮和重金属对厌氧微生物的IC50分别为2 265 mg/L和2.9倍试验用渗滤液的重金属浓度;“中老龄”垃圾渗滤液中氨氮对厌氧污泥的毒性影响较大,高浓度重金属对厌氧污泥活性的抑制较难恢复;实际渗滤液处理工艺中,在采用厌氧工艺前,应对氨氮进行预处理以减少其对厌氧微生物的毒性作用,同时避免水质剧烈波动对厌氧处理系统的冲击。     

基于正交设计的边坡稳定性影响因素敏感性分析

边坡的稳定性受多种因素的影响,应用正交设计对影响边坡的多因素进行了敏感性分析。首先对正交设计原理及用于结果分析的极差法和方差法进行了简单介绍,然后结合工程实例,说明了正交设计在边坡敏感性分析中的应用,最后用极差法和方差法对其结果进行分析,得出影响边坡的参数中,敏感性由大到小依次为:地震加速度α,粘聚力c,内摩擦角φ,库水位变化H,容重γ;其中地震加速度α,粘聚力c,内摩擦角φ是对该边坡影响最显著的因素。因此,在边坡治理时应注意地震和降雨对其稳定性产生的不利影响。     

Epilithic biofilm as a reservoir for functional virulence factors in wastewater-dominant rivers after WWTP upgrade

Virulence factors (VFs) confer upon pathogens the ability to cause various types of damage or diseases. Wastewater treatment plants (WWTPs) are important point sources for the emission of pathogens and VFs into receiving rivers. Conventional WWTP upgrades are often implemented to improve the water quality of receiving ecosystems. However, knowledge on the pathogens, VFs, and health risks to receiving aquatic ecosystems after upgrade remains limited. In this study, we investigated detailed pathogenic information, including taxa, pathogenicity, and health risk, in two wastewater-dominant rivers after WWTP upgrade. Using 16S rRNA gene sequencing, we screened 14 potential pathogens in water and epilithic biofilm samples, though they were significantly more enriched in the biofilms. Combining 16S rRNA and metagenomic sequencing data, we identified Pseudomonas and Aeromonas as the dominant pathogenic taxa carrying functional VFs (e.g., mobility and offensive) in the epilithic biofilm. Moreover, strong pathogen-specific VF-host co-occurrence events were observed in the epilithic biofilm samples, indicating the importance of biofilms as reservoirs and vehicles for VFs. Further, we demonstrated that mobility VF is crucial for biofilm formation and pathogens in biofilm carrying offensive VF may be highly invasive. Quantification and health risk assessment suggested that the skin contact risk of P. aeruginosa carrying VFs was higher than the acceptable probability of 10^?4 in both water and epilithic biofilm samples, which may threaten ecological and human health.     

Collaborative influence of morphology tuning and RE (La,Y, and Sm) doping on photocatalytic performance of nanoceria

Environmental Science and Pollution Research - Tuning morphology and doping additional rare earth (RE) cations are potential techniques to promote the photocatalytic performance of ceria (CeO2),...     

Global burden analysis and AutoGluon prediction of accidental carbon monoxide poisoning by Global Burden of Disease Study 2019

Environmental Science and Pollution Research - Accidental carbon monoxide poisoning (ACOP) is the most common occupational toxic disease, but related data are scarce or non-existent in many...     

Associations between exposure to different heavy metals and self-reported erectile dysfunction: a population-based study using data from the 2001-2004 National Health and Nutrition Examination Survey

Environmental Science and Pollution Research - Heavy metals are ubiquitous and nonbiodegradable pollutants that are widely distributed in the environment. Heavy metal exposure can damage various...     

Application of a combined response surface methodology (RSM)-artificial neural network (ANN) for multiple target optimization and prediction in a magnetic coagulation process for secondary effluent from municipal wastewater treatment plants

Environmental Science and Pollution Research - In this study, an enhanced coagulation-flocculant process incorporating magnetic powder was used to further treat the secondary effluent of domestic...     

Molybdenum background and pollution levels in the Taipu River,China

Environmental Chemistry Letters - Pollution of river sediments by industrial molybdenum (Mo) is a potential threat to human and ecosystem health, yet the lack of a geochemical background level for...