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1.
两室堆肥生物反应装置研究   总被引:1,自引:1,他引:0  
以堆肥过程中物料平衡、热量平衡以及垃圾生物发酵特性为依据,设计了二室堆肥生物反应装置,并通过堆肥试验实际检验反应装置设计的合理性.装置主要结构包括:二室堆肥发酵仓、保温层、通风供氧系统、空气加热系统以及二次污染控制系统.装置的主要特点为:两发酵仓能够独立完成堆肥发酵,也可以实现堆肥一次、二次发酵串联工艺组合;通过二次污染控制系统,可以很好地减少堆肥过程中产生的废水臭气排放;采用空气加热系统,可以快速均匀地加热堆体,以满足不同堆肥工艺的需要.装置在试验研究以及小规模垃圾堆肥处理领域有一定的应用价值.  相似文献   

2.
Field studies were conducted in two different marsh habitats in Louisiana coastal wetlands to evaluate the effects of oiling (using South Louisiana Crude oil, SLC) and the effectiveness of a shoreline cleaner (COREXIT 9580) in removing oil from plant canopies. The study sites represented two major marsh habitats; the brackish marsh site was covered by Spartina patens and the freshwater marsh was covered by Sagittaria lancifolia. Field studies were conducted in each habitat using replicated 5.8 m2 plots that were subjected to three treatments; oiled only, oiled + cleaner (cleaner was used 2 days after oiling), and a control. Plant gas exchange responses, survival, growth, and biomass accumulation were measured. Results indicated that oiling led to rapid reductions in leaf gas exchange rates in both species. However, both species in 'oiled + cleaned' plots displayed improved leaf conductance and CO2 fixation rates. Twelve weeks after treatment initiation, photosynthetic carbon fixation in both species had recovered to normal levels. Over the short-term, S. patens showed more sensitivity to oiling with SLC than S. lancifolia as was evident from the data of the number of live shoots and above-ground biomass. Above-ground biomass remained significantly lower than control in S. patens under 'oiled' and 'oiled + cleaned' treatments while it was comparable to controls in S. lancifolia. These studies indicated that the cleaner removed oil from marsh grasses and alleviated the short-term impact of oil on gas exchange function of the study plants. However, use of cleaner had no detectable effects on above-ground biomass production or regeneration at the end of the first growing season in S. patens. Similarly, no beneficial effects of cleaner on carbon fixation and number of live shoots were apparent beyond 12 weeks in S. lancifolia.  相似文献   

3.
One of the most obvious adverse effects of (chronic) pollution of the world's oceans and seas with mineral oil is the mortality of seabirds. Systematic surveys of beachcast corpses of birds ('beached bird surveys') have been used in many parts of the world to document the effect of oil pollution, but particularly so in Western Europe and in parts of North America. In this paper, the history, current schemes, methods and possible (future) use of beached bird surveys are described and discussed, because the value of beached bird surveys has been hotly disputed. Oil pollution is known since the late 19th century, while the first beached bird surveys were conducted in the 1920s. Due to the amount of man-power needed for these surveys, most beached bird survey programs thrived only through the work of a large number of volunteers. However, most programs have resulted in substantial amounts of high quality data, often covering many consecutive years. One of the main shortcomings of many beached bird survey programs was the emphasis on stranded bird numbers rather than on relative measures, such as oil rates (percentage of corpses oiled of all corpses found). Sources of pollution, particularly so in chronically polluted regions such as the North Sea, the Baltic, the Mediterranean and the waters around Newfoundland, are insufficiently known, but could be studied through a sampling program connected to beached bird surveys. Suggestions for standardization of methods are presented, which could lead to a global and highly sensitive monitoring instrument of marine oil pollution.  相似文献   

4.
The effects of surfactant composition on the ability of chemical dispersants to disperse crude oil in fresh water were investigated. The objective of this research was to determine whether effective fresh water dispersants can be designed in case this technology is ever considered for use in fresh water environments. Previous studies on the chemical dispersion of crude oil in fresh water neither identified the dispersants that were investigated nor described the chemistry of the surfactants used. This information is necessary for developing a more fundamental understanding of chemical dispersion of crude oil at low salinity. Therefore, we evaluated the relationship between surfactant chemistry and dispersion effectiveness. We found that dispersants can be designed to drive an oil slick into the freshwater column with the same efficiency as in salt water as long as the hydrophilic-lipophilic balance is optimum.  相似文献   

5.
Pan X  Zhang D  Quan L 《Chemosphere》2006,65(10):1772-1777
Momoge wetland is an internationally important wetland not only because it is a habitat for many rare bird species but also because it is an internationally important stopover for some rare global migratory bird species. However the petroleum exploitation in wetland has brought about many environmental problems. One of the most severe problems is crude oil pollution, which has caused the dying-off Carex tato and imposes great threat on survival of rare birds. This work studied the factors that caused the dying off of Carex tato. The results showed that death of Carex tato was the result narcosis toxicity of alcohols, intermediate biodegradation products of crude oil, on the root tissue, and the fragmentization of cuticle of leaves by light components of crude oil volatized from soil surface. However, the mechanism involved was much more complex and three interactive factors including crude oil pollution of soil, long-term drought and poor permeability of soil were responsible for the dying-off of Carex tato grassland. The distribution of crude oil in soil profile was characterized with high concentrations at top silty layer and the layer below root zone and low or no crude oil at root zone layer. This distribution was relative to root system characteristics and rhizospheric biodegradation. In root zone, substantive oxygen could be transported to root zone through dense root system and well developed aerenchyma. The crude oil in root zone was easily biodegraded by aerobic rhizosphere microbes. However, some toxic intermediate products, such as some alcohols, was sealed in root zone due to poor permeability of the top soil layer and the deeper soil layer and they had lethal effects on root tissue. Above ground, low molecular components of crude oil in top soil layer was easily volatized into atmosphere during long-term drought. Some of the volatized components were adsorbed onto leaves. SEM analysis showed that these components destroyed the leaves by fragmentization of cuticle of leave. This study also shows that although wetland has natural attenuation of pollutants, natural attenuation of pollutants by natural wetland should not be overemphasized. This attenuation function may lose under some conditions such as long-term drought and poor soil texture.  相似文献   

6.
Guo R  Ebenezer V  Ki JS 《Chemosphere》2012,86(5):512-520
The designation of biodiesel as an environmental-friendly alternative to diesel oil has improved its commercialization and use. However, most biodiesel environmental safety studies refer to air pollution and so far there have been very few literature data about its impacts upon other biotic systems, e.g. water, and exposed organisms. Spill simulations in water were carried out with neat diesel and biodiesel and their blends aiming at assessing their genotoxic potentials should there be contaminations of water systems. The water soluble fractions (WSF) from the spill simulations were submitted to solid phase extraction with C-18 cartridge and the extracts obtained were evaluated carrying out genotoxic and mutagenic bioassays [the Salmonella assay and the in vitro MicroFlow® kit (Litron) assay]. Mutagenic and genotoxic effects were observed, respectively, in the Salmonella/microsome preincubation assay and the in vitro MN test carried out with the biodiesel WSF. This interesting result may be related to the presence of pollutants in biodiesel derived from the raw material source used in its production chain. The data showed that care while using biodiesel should be taken to avoid harmful effects on living organisms in cases of water pollution.  相似文献   

7.
Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered.  相似文献   

8.
矿物油碎火剂的污染问题已越来越引起人们的关注,特别是最近调查表明矿物油是地下水的主要污染源,对矿物油碎火剂进行环保治理的要求更是愈加迫切,首先列出了矿物油碎火剂的环境危害,然后对减少和消除矿物的污染,提出了五种可能的解决办法,延长使用寿命,再生处理,矿物碎火油配方的环保改进,开发新的碎火油和使用水基碎火剂等。  相似文献   

9.
Ecological effects, transport, and fate of mercury: a general review   总被引:42,自引:0,他引:42  
Boening DW 《Chemosphere》2000,40(12):26-1351
Mercury at low concentrations represents a major hazard to microorganisms. Inorganic mercury has been reported to produce harmful effects at 5 μg/l in a culture medium. Organomercury compounds can exert the same effect at concentrations 10 times lower than this. The organic forms of mercury are generally more toxic to aquatic organisms and birds than the inorganic forms. Aquatic plants are affected by mercury in water at concentrations of 1 mg/l for inorganic mercury and at much lower concentrations of organic mercury. Aquatic invertebrates widely vary in their susceptibility to mercury. In general, organisms in the larval stage are most sensitive. Methyl mercury in fish is caused by bacterial methylation of inorganic mercury, either in the environment or in bacteria associated with fish gills or gut. In aquatic matrices, mercury toxicity is affected by temperature, salinity, dissolved oxygen and water hardness. A wide variety of physiological, reproductive and biochemical abnormalities have been reported in fish exposed to sublethal concentrations of mercury. Birds fed inorganic mercury show a reduction in food intake and consequent poor growth. Other (more subtle) effects in avian receptors have been reported (i.e., increased enzyme production, decreased cardiovascular function, blood parameter changes, immune response, kidney function and structure, and behavioral changes). The form of retained mercury in birds is more variable and depends on species, target organ and geographical site. With few exceptions, terrestrial plants (woody plants in particular) are generally insensitive to the harmful effects of mercury compounds.  相似文献   

10.
对采自胜利油田的采油废水,分别进行了聚硅硫酸铁(PFSS)絮凝法、微纳气泡法和絮凝-微纳气泡联合法处理,考察了处理过程对采油废水水质和所配制聚合物(部分水解聚丙烯酰胺)溶液粘度的影响。结果表明,均可有效降低废水的矿化度、油含量和悬浮物含量,明显提高用其配制的聚合物溶液的粘度;联合处理效果明显高于单独采用絮凝或微纳气泡处理的效果。所处理后的废水可有望代替淡水用于油田现场配制聚合物驱油体系,在消除油田污水环境污染的同时,可节约淡水资源。  相似文献   

11.

Background, aim, and scope  

The blue swallow (Hirundo atrocaerulea) is one of the most threatened bird species in southern Africa. Among terrestrial birds, its plumage is known to be the most water repellent, an adaptation to foraging on the wing in dense fog. Despite this unique adaptation, the nesting success of the blue swallow at the Blue Swallow Natural Heritage Site (BSNHS) is lower during years with high incidence of fog. As the phenomenon is not observed at other nesting sites, we hypothesized that this is due to changes in the air chemistry at the BSNHS. In the immediate proximity of the BSNHS, plantations of exotic trees (e.g., pines and eucalypts), rich in volatile organic compounds (VOCs), are dominant features. In addition, air pollution from the Johannesburg area is transported with the surface winds and mix with VOCs released from exotic trees. Together with the high humidity and high elevation, these conditions may result in the formation of sulphonates. Sulphonates are strong detergents, and the presence of these in the fog could lead to decreased water repellence of the plumage. This study was performed in order to determine the occurrence and distribution of sulphonates in the BSNHS and to compare these with sulphonates formed in other locations in South Africa. Because the blue swallow is endangered, pine needles were used as proxy to detect formation of sulphonates.  相似文献   

12.
Development of efficient techniques to combat the harmful effects of oil spill is an emerging field, where fabrication of new sorbents for selective removal of oil has become a hot topic for environmental scientists. The present study reports the preparation of superhydrophobic/oleophilic magnetic titania nanotubes via a facile hydrothermal method, followed by the treatment with octadecylamine, as potential magnetically driven sorbent for selective removal of oil from water surface. The magnetic nature (superparamagnetism at 300 K) of the nanotubes enabled magnetic removal of the oil-sorbed material from water surface. Wettability test of the material depicted a static water contact angle of 166 ± 1°, indicating its superhydrophobic character. Oil uptake experiments and contact angle measurements revealed its superoleophilicity with maximum oil sorption capacity >1.5 g/g for a variety of oils. In addition to the ease of magnetic removal, the nanotubes possess sufficient buoyancy, high selectivity, and quick rate of oil uptake and is more than five times reusable.  相似文献   

13.
Chlorophyll plays a pivotal role in the plant physiology and its productivity. Cultivation of plants in crude oil contaminated soil has a great impact on the synthesis of chlorophyll pigment. Morpho-anatomy of the experimental plant also shows structural deformation in higher concentrations. Keeping this in mind, a laboratory investigation has been carried out to study the effect of crude oil on chlorophyll content and morpho-anatomy of Cyperus brevifolius plant. Fifteen-day-old seedling of the plant was planted in different concentrations of the crude oil mixed soil (i.e., 10,000, 20,000, 30,000, 40,000, and 50,000 ppm). A control setup was also maintained without adding crude oil. Results were recorded after 6 months of plantation. Investigation revealed that there is a great impact of crude oil contamination on chlorophyll content of the leaves of the experimental plant. It also showed that chlorophyll a, chlorophyll b, and total chlorophyll content of leaves grown in different concentrations of crude oil were found to be lower than those of the control plant. Further, results also demonstrated that chlorophyll content was lowest in the treatment that received maximum dose of crude oil. It also showed that chlorophyll content was decreased with increased concentration of crude oil. Results also demonstrated that there was a reduction in plant shoot and root biomass with the increase of crude oil concentration. Results also revealed that the shoot biomass is higher than root biomass. Morphology and anatomy of the experimental plant also show structural deformation in higher concentrations. Accumulation of crude oil on the cuticle of the transverse section of the leaves and shoot forms a thick dark layer. Estimation of the level of pollution in an environment due to oil spill is possible by the in-depth study of the harmful effects of oil on the morphology and anatomy and chlorophyll content of the plants grown in that particular environment.  相似文献   

14.
Three oil spill situations which cause long-term impact were simulated in 1 m(2) salt marsh plots to evaluate the effectiveness of alternative cleanup techniques at removing oil and reducing damage to Spartina alterniflora. Cleanup techniques, implemented 18-24 h after oiling, were not effective at removing oil after sediment penetration. When oil remained on the sediment surface, flushing techniques were most effective at removal, reducing levels of added oil by 73% to 83%. The addition of dispersant to the flushing stream only slightly enhanced oil removal. Clipping of vegetation followed by sorbent pad application to sediment was moderately effective, reducing added oil by 36% to 44%. In contrast to flushing and clipping, burning increased the amount of oil in sediment by 27% to 72%. Although flushing and clipping were effective at oil removal, neither technique reduced initial damage to plants or enhanced long-term recovery. While flushed plots sustained no additional plant damage due to cleanup, clipped and burned plots sustained additional initial plant damage. Based on these results, first considerations should be given to natural tidal flushing as the means to remove oil, especially in salt marshes subject to ample tidal inundation. Although our results do not support cleanup in salt marshes with ample tidal inundation, low pressure flushing may be warranted when fuel oils or large quantities of crude oil impact salt marshes subject to reduced tidal flushing. Flushing, when warranted, should be initiated prior to oil penetration into the substrate. Clipping may be considered as a cleanup response only when heavy oil cannot be effectively removed from vegetation by flushing. Burning is not recommended because it enhances oil penetration into sediment and causes substantial initial plant damage.  相似文献   

15.
The objective of this review was to synthesize existing information regarding the effects of petroleum hydrocarbons on marsh macrophytes in a manner that will help guide research and improve spill-response efficiency. Petroleum hydrocarbons affect plants chemically and physically. Although plants sometime survive fouling by producing new leaves, even relatively non-toxic oils can stress or kill plants if oil physically prevents plant gas-exchange. Plant sensitivity to fouling varies among species and among populations within a species, age of the plant, and season of spill. Physical disturbance and compaction of vegetation and soil associated with clean-up activities following an oil spill appear to have detrimental effects on the US Gulf coast marshes. Other techniques, including the use of chemicals such as cleaners or bioremediation, may be necessary to address the problem. Clean-up may also be beneficial when timely removal prevents oil from migrating to more sensitive habitats.  相似文献   

16.
Reactive nitrogen and human health: acute and long-term implications   总被引:5,自引:0,他引:5  
Wolfe AH  Patz JA 《Ambio》2002,31(2):120-125
Reactive-nitrogen (Nr) has a wide variety of beneficial and detrimental effects on human health. The most important of the beneficial effects are increasing global and regional food supplies and increased nutritional quality of available foods. However, lack of adequate dietary intake of amino acids and proteins is a serious cause of malnutrition when food supplies are inadequate because of poverty, drought, floods, wars, and displacements of people as refugees. There is sufficient, though limited, quantitative data indicating that increased circulation of Nr in the environment is responsible for significant human health effects via other exposure pathways. Nr can lead to harmful health effects from airborne occupational exposures and population-wide indoor and outdoor air pollution exposures to nitrogen dioxide and ozone. Nr can also affect health via water pollution problems, including methemoglobinemia from contaminated ground water, eutrophication causing fish kills and algal blooms that can be toxic to humans, and via global warming. The environmental pollutants stemming from reactive nitrogen are ubiquitous, making it difficult to identify the extent to which Nr exerts a specific health effect. As all populations are susceptible, continued interdisciplinary investigations are needed to determine the extent and nature of the beneficial and harmful effects on human health of nitrogen-related pollutants and their derivatives.  相似文献   

17.
采油污水生物处理技术   总被引:1,自引:0,他引:1  
采油污水是石油工业中的重点污染源之一。本文论述了采油污水生物处理的难度和技术可行性 ,总结了国内外近年来采油污水生物处理技术的现状及研究进展。  相似文献   

18.
Chronic oil pollution by illegal oil dumping in the North Sea is difficult to quantify. Beached, oil-contaminated sea birds, however, may be used as an indirect indicator. Reconstructing the drift of oil slicks and sea bird corpses in the southern North Sea for the period 1992-2003 by means of a two-dimensional numerical transport model driven by re-analysed weather data, we show with an example of two common sea bird species that the variability observed within the number of corpses registered during beached bird surveys for the German coast primarily reflects the inter-annual variability of prevailing weather conditions. This should be taken into account when interpreting the data. We propose normalisation of beached bird survey data based on numerical drift simulations to improve the recognition of trends in the level of chronic oil pollution.  相似文献   

19.
Environmental Science and Pollution Research - The current study aims to explore the impact of palm oil fuel ash (POFA) heat treatment on the strength activity, porosity, and water absorption of...  相似文献   

20.
During the winter of 1993-94, male lesser scaup (Aythya affinis) were collected on the heavily polluted Indiana Harbor Canal (IHC), East Chicago, IN, USA, and examined for tissue contaminant levels. Lesser scaup collected on the IHC had higher concentrations of cadmium (Cd), mercury (Hg), selenium (Se), polychlorinated biphenyls (PCBs), selected organchlorine pesticides, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, polycyclic aromatic hydrocarbons, and aliphatic hydrocarbons than reference birds. Of the scaup collected on the IHC, 44% had Cd concentrations in the liver considered above background for freshwater waterfowl (>3 microg/g dry wt.), 50% had Se concentrations in the liver above a level possibly harmful to the health of young and adult birds (>33 microg/g dry wt.), and 88% of the scaup carcasses exceeded the PCB human consumption guidelines for edible poultry in the USA (>3.0 microg/g lipid wt.). The ratio of pristane:n-heptadecane concentrations in 47% of lesser scaup collected on IHC was elevated above 1.0, which is indicative of chronic exposure to petroleum hydrocarbons.  相似文献   

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