生物滴滤池脱除烟气中SO2的实验研究

将分离筛选得到的氧化亚铁硫杆菌固定在生物滴滤池的填料上,组成生物滴滤池反应系统,并研究了进气SO2浓度、气体流量、液气比、循环液中铁离子浓度对脱硫效率的影响,此外还分析了该反应系统的脱硫机理.     

生物滴滤池脱除烟气中SO2的实验研究

将分离筛选得到的氧化亚铁硫杆菌固定在生物滴滤池的填料上，组成生物滴滤池反应系统，并研究了进气SO2浓度、气体流量、液气比、循环液中铁离子浓度对脱硫效率的影响，此外还分析了该反应系统的脱硫机理。     

自然通风生物滴滤池的填料挂膜特性研究

研究了自然通风生物滴滤池内浮石、聚氨酯两种填料的挂膜特性,考察不同工况下的污水净化规律。结果表明,浮石填料在生物滴滤池内的挂膜效果更好,挂膜成功后对COD、NH+4-N均有较好的去除效果,去除率大都分别达到70%～85%、60%～80%,且小粒径浮石比大粒径浮石的去除效果更佳。聚氨酯填料在第9天挂膜成功,大粒径聚氨酯填料对COD的去除效果略好于小粒径聚氨酯填料,挂膜成功后两者对COD的去除率均可以达到60%～80%,而对NH+4-N的去除效果较差,去除率仅达到10%～40%。浮石填料生物滴滤池对TN、TP的去除率较好,当水力负荷为0.85m3/(m2·d)时,TN、TP去除率分别为45.58%、38.44%,而聚氨酯填料生物滴滤池对TN、TP的去除率较差。浮石在挂膜生物量上占优势,聚氨酯的孔径较大,污水流经时停留时间较短,使得微生物不易附着其上。     

ABR-生物滴滤池组合工艺处理农村生活污水

采用ABR-生物滴滤池组合工艺,研究在水力停留时间为3 d、滴滤池水力负荷为5 m3/（m2·d）的条件下,组合工艺对生活污水中主要污染物的去除效果、滴滤池内部污染物浓度变化和微生物的沿程分布规律。实验结果表明,组合工艺对COD、TN、NH＋4-N和TP的平均去除率分别可达73%、32%、58%和30%;滴滤池内各层污染物浓度除TP在中层略有升高外,其余均沿程逐渐降低。滴滤池底层对各种污染物的去除能力均较强,原因是果壳活性炭填料较强的截留吸附能力以及底层微生物优势菌属较好的降解作用。总氮的去除依靠滴滤池内填料的物理化学作用和微生物同步硝化反硝化作用,其中微生物作用约占60%,成为脱氮的主要途径。     

挥发性有机污染物与恶臭的生物处理技术及其工艺选择

本文介绍了生物滤池、生物洗涤塔和生物滴滤池处理挥发性有机污染物及恶臭的特性、近期发展状况及其应用。阐述了亨利系数在选择生物处理技术中的作用 ,以及生物反应器内填料、微生物的选择     

复合生物滤池处理H2S和NH3的挂膜与工艺条件

采用复合生物滤池(生物滴滤池 生物过滤池)处理H2S和NH3组成的混合恶臭气体,填料分别为经表面改性的天然斜发沸石和木屑.实验研究了该工艺的驯化挂膜情况和主要工艺条件,结果表明,天然斜发沸石和木屑改性后,驯化挂膜周期为10～14 d,比文献中颗粒活性炭挂膜缩短14～18 d.复合生物滤池的最佳工艺条件为:高度120 cm,循环液流量4.56 L/h.同时,生物滴滤池处理水溶性好的NH3气体效果较生物过滤池好,而生物过滤池处理水溶性差的H2S气体较生物滴滤池好.因此,复合生物滤池可用于处理不同水溶性的混合恶臭气体.     

挥发性有机污染物与恶臭的生物处理技术及其工艺选择

本文介绍了生物滤池、生物洗涤塔和生物滴滤池处理挥发性有机污染物及恶臭的特性、近期发展状况及其应用。阐述了亨利系在选择生物处理技术中的应用,以及生物反应器内填料、微生物的选择。     

生物滴滤法去除低浓度苯乙烯

通过装载改性聚乙烯填料的生物滴滤塔进行废气中的苯乙烯生物降解实验。结果表明,通过快速排泥法挂膜,该反应器可在较短周期内实现微生物的驯化。苯乙烯入口浓度和空床停留时间(EBRT)是影响反应器性能的重要因素,当EBRT分别为60、45、30和15 s以及对应的入口浓度分别为950、430、350和200 mg/m3时,可实现达标排放。循环喷淋液中的硝酸盐(亚硝酸盐)对生物滴滤池的影响十分明显,在初始阶段,亚硝酸根很快被耗尽,硝酸根则相对缓慢。当循环液中的TN从102.63 mg/L下降到24.24 mg/L时,滴滤池的去除效率由94.48%下降到43.16%,部分原因是降低NOx-的浓度减弱了反硝化作用对VOC碳源的利用。     

上向流曝气生物滤池水头损失沿程分布与动态特性

对比考察了天然斜发沸石、页岩陶粒和石灰岩碎石填料曝气生物滤池的水头损失增长规律,分析了3种滤池水头损失的空间分布特征和动态变化特性,探讨了截留固体累积量对水头损失发展的影响规律。结果表明,沸石、陶粒和石灰岩曝气生物滤池均具有较好的有机物和SS沿程去除能力,并与水头损失的沿程分布密切相关;滤池内部TSS的沿程变化趋势和水头损失沿程分布趋势基本一致;曝气生物滤池的水头损失随着反应器运行时间的延长而缓慢增加,当滤床内TSS积累量增加到一定程度时,气体的滤床驻留率增加,并与TSS积累协同作用,滤床局部孔隙率迅速下降,水头损失迅速越升。曝气生物滤池的反冲洗首先应着眼于解决滤床的局部孔隙率过低问题,然后以气洗促进颗粒碰撞,气水联合提高剪切力,最后水漂洗排出TSS和气泡。     

间歇运行式生物滴滤池处理油漆废气中试研究

为研究间歇运行式生物滴滤池对油漆生产厂废气净化能力,建立一座中试规模生物滴滤池（BTF）,接种降解菌群,采用8 h/d运行方式净化某油漆厂包装车间废气,并用PCR-DGGE技术揭示BTF细菌群落结构与工艺运行条件间的联系。油漆厂包装车间废气中挥发性有机物（VOCs）主要为甲苯、乙苯、混合二甲苯（间、对和邻二甲苯）,BTF对甲苯、乙苯、混合二甲苯最大去除率分别为88.8%、83.7%和86.3%。DGGE分析显示,BTF稳定运行时,主要优势菌相对丰度较为稳定（F,P>0.05）,其细菌多样性显著低于启动期（F,P>0.05）;同时,下层填料细菌多样性高于上层填料,其细菌结构变化也较上层明显;另外,提升培养液浓度至2倍和4倍对菌群结构亦无显著影响。     

Investigation of the characteristics of the reflectivity of clouds

This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).     

底泥修复中温度对微生物活性和污染物释放的影响

通过分析底泥中微生物的酶活性以及污染物的释放规律,探讨了温度对河道底泥生物修复的影响.结果表明,底泥中微生物的脱氢酶、脲酶和磷酸酶的活性随着温度的升高而显著增大,但温度对纤维素酶的活性影响较小.4 ℃和10 ℃时底泥中污染物的释放量和微生物的酶活性均较低,水质较稳定;20～37 ℃时底泥中污染物的释放量明显增加,微生物的新陈代谢能力有较大提高,水体的自净能力较强.在各种因素的综合作用下,20～30 ℃是进行底泥生物修复的适宜环境温度.此外,当pH为9.0以及添加葡萄糖时,底泥中微生物均表现出较高的脱氢酶活性.     

How the loss of forest fauna undermines the achievement of the SDGs

The human-driven loss of biodiversity has numerous ecological, social, and economic impacts at the local and global levels, threatening important ecological functions and jeopardizing human well-being. In this perspective, we present an overview of how tropical defaunation—defined as the disappearance of fauna as a result of anthropogenic drivers such as hunting and habitat alteration in tropical forest ecosystems—is interlinked with four selected Sustainable Development Goals (SDGs). We discuss tropical defaunation related to nutrition and zero hunger (SDG 2), good health and well-being (SDG 3), climate action (SDG 13), and life on land (SDG 15). We propose a range of options on how to study defaunation in future research and how to address the ongoing tropical defaunation crisis, including but not limited to recent insights from policy, conservation management, and development practice.     

Industrial plastic on the southern beaches of the Arabian Gulf and the western beaches of the Gulf of Oman

The increasing production and use of plastic in the Arabian Gulf combined with shipping and waste disposal practices, have increased the concentration of plastic particles on the sea's surface and beaches. The objective of this investigation was to provide an assessment of the abundance, distribution, potential sources and significance of industrial plastic on the western beaches of the United Arab Emirates on the Arabian Gulf and on the eastern beaches on the Gulf of Oman. The abundance of stranded plastic pellets was highly uneven. By early 1992 alarming levels of fresh plastic pellets were noticed on the Arabian Gulf beaches of the UAE. Large numbers of 25 kg sacks of white plastic spherules manufactured by (SABIC) in Jubail, Saudi Arabia were washed ashore. When compared to the west coast on the Arabian Gulf, the east coast on the Gulf of Oman exhibited much lower levels of plastic pellets. When compared to other parts of the world, the beaches of the UAE on the Arabian Gulf are considered to be heavily polluted with industrial plastic.     

The Governance of the Mitigation of the Baltic Sea Eutrophication: Exploring the Challenges of the Formal Governing System

This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a “primus motor” for the governance of the mitigation of eutrophication in the Baltic Sea.     

Effect of the pesticide lindane on the biomass of the microalgae Nannochloris oculata

This study assesses the growth of the microalgae Nannochloris oculata in the presence of lindane and the ability of N. oculata to remove lindane from media. Algal biomass increased with 0.1 and 0.5 mg L^?1 of lindane, and lindane concentrations in the media decreased. N. oculata removed 73% and 68.2% of lindane in the 0.1 and 0.5 mg L^?1 media concentrations, respectively. Algal biomass decreased to the level of the control at lindane concentrations greater than 2.5 mg L^?1, probably due to toxicity. N. oculata removed lindane from the media at concentrations lower than 1.0 mg L^?1. Thus, N. oculata may be useful for lindane bioremediation in contaminated aquatic systems.     

Influence of the application of sewage sludge on the degradation of pesticides in the soil

A study was made of the influence of the application of sewage sludge on the degradation of pesticides in the soil. Two kinds of sludge were used, with different characteristics, one from an urban treatment plant and one from a food processing plant. Three organophosphorus insecticides, fenitrothion, diazinon and dimethoate, were studied. The relative importance was determined of the chemical and biological degradation processes, which involved experiments on soil and sterile soil samples. A comparative study was also made of the degradation of pesticide residues and the evolution of the microbial population. The application of sludge seems to have a complex effect on the degradation of pesticides, determined by the bioavailability and biodegradability of their active ingredient. The biodegradation of pesticide residues brings about alterations in the microorganism population of the soil.     

Assessment of the effects of the carbamazepine on the endogenous endocrine system of Daphnia magna

In the present study, the endocrine activity of the antiepileptic pharmaceutical carbamazepine (CBZ) in the crustacean Daphnia magna was assessed. To assess the hormonal activity of the drug, we exposed maternal daphnids and embryos to environmental relevant concentrations of CBZ (ranging from 10 to 200 μg/L) and to mixtures of CBZ with fenoxycarb (FEN; 1 μg/L). Chronic exposure to CBZ significantly decreased the reproductive output and the number of molts of D. magna at 200 μg/L. This compound induced the production of male offspring (12?±?1.7 %), in a non-concentration-dependent manner, acting as a weak juvenile hormone analog. Results showed that this substance, at tested concentrations, did not antagonize the juvenoid action of FEN. Further, CBZ has shown to be toxic to daphnid embryos through maternal exposure interfering with their normal gastrulation and organogenesis stages but not producing direct embryo toxicity. These findings suggest that CBZ could act as an endocrine disruptor in D. magna as it decreases the reproductive output, interferes with sex determination, and causes development abnormality in offspring. Therefore, CBZ could directly affect the population sustainability.

     

Isolation of the stable fraction (the core) of the humic acid

Humic acid consists of a recalcitrant (unhydrolysed fraction) (the core) and labile (hydrolysable fraction) fraction. Core-humic acid (core-HA) isolation was performed by treating source material with apolar and polar solvents (organic solvents+acid hydrolysis) before alkaline extraction. Leonardite, soil Ah horizont and dry blood were chosen for this study because of their different origin and degree of humification. Chemical analysis (elemental analysis, total acidity, E(4):E(6)), spectroscopic analysis (DRIFT and (1)H NMR), and complete mass balance were used to investigate the effect of purifying humic acids. The results obtained showed that purification produced a slight modification of Leonardite humic acids as was expected for these highly humified organic matrices. On the other hand, about 500 g kg(-1) of soil humic acids were lost by purification. The fractions lost mainly consisted of carbohydrates. Dry blood showed the presence of humic acids that contrasted with its origin, thus indicating the limitations of the common analytical methods used for HA extraction. Nevertheless, in practice, purification caused the complete disappearance (914 g kg(-1) of HA was lost) of these HAs. The results obtained in this work suggest that the HA fraction isolated (named core-HA) effectively represents the HA structure proposed by the existing literature, since the purification proposed was able to eliminate the adsorbed organic molecules (interference materials) coating the HA structure.