溢油污染处置技术现状分析

大规模的海洋溢油常常导致非常严重的环境污染事件和生态灾难,溢油事故应急是世界应急技术领域面临的重大技术难题。文章通过引用典型事故案例和国内事故概况说明了溢油事故的巨大风险及其危害,分析油品入水、扩散、漂移以及着陆四个不同事故演化阶段的污染特征,系统梳理溢油事故应急的物理、化学和生物处置方法,并通过对比各类方法的适用范围和优缺点,总结当前溢油应急处置技术、应急能力以及环境适应性等方面存在的不足,提出加强溢油应急处置能力应该在提高应急装备能力、开发新技术产品、建立全球联动机制等方面加强努力。     

MWCNTs预涂覆及预吸附处理缓解低压膜腐殖酸污染的机制研究

以腐殖酸(Humic Acid,HA)为研究对象,采用多壁碳纳米管(Multiwalled Carbon Nanotubes,MWCNTs)对聚偏氟乙烯(Polyvinylidene Fluoride,PVDF)平板超滤膜进行预涂覆改性处理,并与等量MWCNTs分散状态时吸附处理HA对膜污染的缓解效果进行了对比,考察了MWCNTs在处理HA过程中缓解膜污染的机制.同时,分析了MWCNTs投量和溶液离子变化对MWCNTs吸附及截留作用缓解膜污染的影响.结果表明,MWCNTs预涂覆与吸附相比,能够更有效地缓解膜污染,其中,分散剂为乙醇的MWCNTs预涂覆层对膜污染的缓解效果最好.增加MWCNTs投量不能无限地提高其对HA的吸附及截留效果;添加Na~+会造成MWCNTs对HA的吸附及截留效果变差;添加Ca~(2+)能够提高MWCNTs对HA的吸附及截留效果.膜表面污染照片及膜电镜观测结果表明,乙醇分散MWCNTs在超滤膜(UF)表面形成的预涂覆层呈均匀的层状结构,HA被拦截在MWCNTs层的多孔结构内,不易进入PVDF膜膜孔,反洗时易脱附,可逆性高;纯水分散MWCNTs在超滤膜表面形成的预涂覆层易于团聚,HA容易透过MWCNTs涂覆层进而堵塞PVDF膜膜孔,可逆性低;MWCNTs预吸附处理后形成MWCNTs和HA的包裹体,不经微滤膜滤除,会在PVDF膜表面产生复合污染.     

Water quality characteristics and assessment of Yongding New River by improved comprehensive water quality identification index based on game theory

The Yongding New River is essential for the water supplies of Tianjin. To date, there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream. Moreover, little attention has been given to determining a combined weight for improving the traditional comprehensive water quality identification index (ICWQII) by the game theory. Seven water quality parameters were investigated monthly along the main stream of the Yongding New River from May 2018 to April 2019. Organic contaminants and nitrogen pollution were mainly caused by point sources pollution, and the total phosphorus mainly by non-point source pollution. Dramatic spatio-temporal variations of water quality parameters were jointly caused by different pollutant sources and hydrometeorological factors. In terms of this study, an improved comprehensive water quality identification index (ICWQII) based on entropy weight or variation coefficient and traditional CWQII underestimated the water qualities, and an ICWQII based on the superstandard multiple method overvalued the assessments. By contrast, water qualities assessments done with an ICWQII based on the game theory matched perfectly with the practical situation. The ICWQII based on game theory proposed in this study takes into account not only the degree of disorder and variation of water quality data, but also the influence of standard-exceeded pollution indicators, whose results are relatively reasonable. All findings and the ICWQII based on game theory can provide scientific support for decisions related to the water environment management of the Yongding New River and other waters.     

Feedbacks of flow and bed morphology from a submerged dense vegetation patch without upstream sediment supply

Environmental Fluid Mechanics - Laboratory experiments were performed to investigate how flow patterns and bed morphology are affected around a submerged vegetation patch in the condition without...     

Flow depth,velocity, and sediment motions in a straight widened channel with vegetated floodplains

Environmental Fluid Mechanics - Experiments were conducted in a straight channel that widens from a single channel to a compound channel based on a real navigation channel with a similar shape in a...     

资源利用最优化的经济学探讨

本文假设资源作为可持续发展巨系统的一个子系统,其运行目的是经济效益最佳,从经济学角度提出了求资源最优利用水平的方法     

医用玻璃及医疗垃圾灰渣的结渣特性研究

医疗垃圾的特性和成分是改善焚烧装置设计、运行及控制性能的重要参数.为了研究医用玻璃对医疗垃圾焚烧炉的影响,从医疗废物处置中心采集了玻璃和灰渣样品,分析了其化学组分和熔融温度.与煤灰成分相比,医用玻璃中的SiO2和碱金属氧化物含量较高.通过不同玻璃间的比较,总结了化学组分对熔融温度的影响.软化温度随着SiO2、CaO含量的增加而升高,但随B2O3、Na2O含量的增加而迅速降低.改变不同玻璃的混合比例.研究了混合玻璃的熔融特性.利用煤灰结渣指数对医疗垃圾灰渣的结渣倾向进行了判定.结果显示,仅沾污指数能够对灰渣得出适宜的判别.     

天然气水合物与全球气候变化的关系

天然气水合物是一种广泛地存在于海底沉积物和陆地高纬度永久冻土带中的矿物,含碳量超过全球所有其他来源有机碳的总和。然而天然气水合物在自然界极不稳定,温压条件的微小变化都会引起其分解而释放出甲烷气体。一般情况下,释放出的甲烷大部分可能会被氧化成CO2而溶解在海水中,进入大气中的量不足以对气候产生影响。只有在发生巨变事件的情况下,如海底大规模的沉积物滑塌,才会将大量的甲烷带到海面并释放到大气中,从而对全球气候和环境产生严重的影响。因此,在开发利用天然气水合物之前,必须有超前的防范措施,以防止或尽可能减少天然气水合物对环境造成的不良影响。     

甜叶菊萃取工业的废水处理工程调试思路探讨

甜叶菊萃取工业的废水是一种高浓度、难降解废水,是目前污染较重的工业废水之一。以江西某生物技术公司所产生的甜叶菊萃取工业的废水处理工程中的问题为例,深入剖析了其症结所在,并针对其实际情况提出了一定的整改措施和方案,最后从原理上对这些整改方案进行了解析,以期为该工业废水的处理提供参考。