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1.
碱渣与饱和卤水混合制成浆体回填到盐矿废弃盐腔可同时解决碱渣处理问题和地下废弃盐腔存在的地质隐患。回填碱渣强度是影响充填效果的重要因素。因此,为了提高回填碱渣强度,采用掺入粉煤灰制成复合碱渣对其强度特性进行改良。针对不同粉煤灰掺合比的碱渣开展了组成、力学和细观试验。研究结果表明：（1）掺入粉煤灰能明显改善碱渣的强度,使其黏聚力、内摩擦角都大幅提高,抗剪强度大幅增加;（2）粉煤灰掺合比越大,增强效果越明显,但强度并非随掺合比呈线性变化,对黏聚力而言,在0～20%内的掺合比下增加速度最快,而对内摩擦角则在20%～30%的掺合比区间增加最快,对抗剪强度而言,0～20%的掺合比内增加最明显;（3）粉煤灰掺入还可显著改善碱渣的压缩固结特性,使其固结系数大幅提高,从而提高碱渣固结速度,缩短充填工期,其中在0～10%的掺合比内对压缩固结特性改善最显著;（4）矿物组成分析表明,粉煤灰掺入改变了矿物组成,使得亲水性矿物含量急剧锐减,进而改变了其沉积特性。而细观分析则表明,粉煤灰掺入使碱渣从絮凝团细观结构变成了粉煤灰充当骨架的充填结构,且粒间支撑和拉联效应明显。从增强效果提高、压缩固结特性增强、控制成本和工期综合分析表明,最优掺合比为20%左右,建议工程中以不高于20%的掺合比作为实用掺合比即可取得较为理想的充填增强效果。该研究为揭示碱渣增强机制及废弃盐腔碱渣充填工艺优化提供了有益参考。 相似文献
2.
A systematic archaeoseismological study indicates that at least three earthquakes occurred between 400 B.C. and A.D. 600, causing destruction to numerous ancient monuments in Sicily. Evidence for these earthquakes comes from the collapse style of buildings (toppled walls, column drums in a domino‐style arrangement, directional collapses, etc.), and the exclusion of other likely causes for such effects. Dating of inferred earthquakes is based on coins (accurate to within 5–10 years), pottery (accurate to within 50–200 years), and other artifacts. The oldest documented earthquake occurred between 370 and 300 B.C. and caused the collapse of two Greek temples in Selinunte. This otherwise poorly documented event was probably also the cause of extensive destruction in northeastern Sicily in the first century A.D. Destruction of some sites may be assigned to an earthquake that occurred between 360 and 374 and correlates with the A.D. 365 seismic sequence known from historical sources. This study covers a wider region and provides a more precise dating of earthquakes than previous studies. Although it focuses on a certain period (4th–3rd centuries B.C., 4th–7th centuries A.D.), it indicates that the period before A.D. 1000 is not a period of seismic quiescence in Sicily as was previously believed, but to a period characterized by strong and destructive earthquakes. © 2009 Wiley Periodicals, Inc. 相似文献
3.
H. R. Guzmán-Carrillo J. M. Pérez E. A. Aguilar Reyes M. Romero 《International Journal of Environmental Science and Technology》2018,15(8):1757-1766
The aim of this research was to evaluate the feasibility of using the vitrification process as an alternative solution to the disposal of a coal fly ash and metallurgical slags in landfills. The starting wastes were characterised in terms of chemical, granulometric, mineralogical, and microstructural analysis. A selected batch composition composed by 58.5% fly ash, 31.5% metallurgical slag and 10.0 Na2O% (wt%) was melted at 1450 °C and poured to obtain monolithic glass samples. The environmental behaviour of the starting wastes and the resulting glass was evaluated by standard leaching tests, which shows that vitrification leads to a stabilisation process in which the inorganic components of the wastes are immobilised throughout their incorporation into the glass structure. Moreover, vitrification transforms those hazardous wastes into a new non-hazardous glass. A preliminary study shows that the new glass is suitable for developing glass–ceramic tiles appropriate for floor pavement and wall covering. 相似文献
4.
气相色谱法分析固体废物中苯酚类物质 总被引：2，自引：0，他引：2
通过一系列筛选实验,确定了一种使用国产毛细管色谱柱分离固体废弃物中苯酚类物质的气相色谱分析方法,固体废弃物中苯酚类物质的回收率均可达70%以上,5次测定的相对标准偏差RSD＜6%,检出限(mg/kg)苯酚为0.033,邻甲酚为0.039,对甲酚为0.046,间甲酚为0.054,可以满足固体废弃物中苯酚类物质测定的要求. 相似文献
5.
S. Nasirahmadi A. A. Safekordi Ph.D. 《International Journal of Environmental Science and Technology》2011,8(4):823-830
While oil prices raise and the supply remains unsteady, it may be beneficial to use the high content of energy available in food processing wastes, such as cheese whey waste, by converting it to bioenergy. As well, there have been many new waste biotreatment technologies developed recently, which may well be used directly to food processing wastes. Microbial fuel cell represents a new technology for simultaneous use of waste materials and bioelectricity generation. In this study, bioelectricity generation with whey degradation was investigated in a two-chamber microbial fuel cell with mediators. E.coli was able to use the carbohydrate found in whey to generate bioelectricity. The open-circuit voltage in absence of mediator was 751.5mV at room temperature. The voltage was stable for more than 24 h. Riboflavin and humic acid were used as conceivable mediators. The results showed that humic acid was a few times more effective than Riboflavin. Additionally, four chemicals employed as catholyte. Based on polarization curve, FeCl3 (III) was the best. Maximum power generation and current were 324.8 μW and 1194.6μA, respectively. 相似文献
6.
神农架大九湖15.753kaB.P.以来的孢粉记录和环境演变* 总被引：10，自引：2，他引：10
根据对大九湖297cm厚的泥炭地层10个AMS 14 C年龄的测定以及148块孢粉样品的分析,发现每块样品的孢粉(浓度)含量都很高,植物种类繁多,分属于137(科)属,可划分为6个孢粉组合带,植被类型演替大体为:含少量常绿树种的针阔叶混交林—含常绿阔叶树种的落叶阔叶林—常绿落叶阔叶林—含常绿阔叶树种的落叶阔叶林—含少量常绿树种的针阔叶混交林。孢粉带Ⅰ(15.753~11.280kaB.P.)记录了该区域晚冰期及其向全新世过渡时期冷暖波动频繁的气候条件,其中亚带Ⅰ -1(15.753~15.549kaB.P.),Ⅰ -3(14.936~14.505kaB.P.)和Ⅰ -5(12.655~11.280kaB.P.)可能分别对应最老仙女木期、老仙女木和新仙女木冷期,而亚带Ⅰ -2(15.549~14.936kaB.P.)和Ⅰ -4(14.505~12.655kaB.P.)分别对应博令和阿勒罗德暖期。孢粉带Ⅱ(11.280~9.218kaB.P.)代表了由晚冰期冷湿气候向全新世温暖气候转换的早全新世缓慢升温的过渡时期。孢粉带Ⅲ(9.218~7.530kaB.P.)代表中全新世前期的气温波动上升期,7.7kaB.P.前后达到最高温。孢粉带Ⅳ(7.530~4.051kaB.P.)代表中全新世适宜期,水热配置条件最佳。孢粉带Ⅴ(4.051~0.911kaB.P.)体现晚全新世温干的气候。孢粉带Ⅵ(0.911~0kaB.P)反映了大九湖温凉稍湿的气候。 相似文献
7.
湖北梁子湖近代沉积记录对人类活动的响应 总被引：4，自引：1，他引：3
为了研究人类活动背景下的湖泊生态响应过程和机制, 分析人类活动对湖泊富营养化的贡献, 在210Pb计年和历史事件记载基础上, 通过梁子湖沉积物水生生物遗存和色素分析重建了梁子湖地区过去100多年来湖泊生态系统演化过程.沉积物色素和水生生物遗存组合带的变化表明梁子湖营养演化具有5个阶段: 过去100多年梁子湖地区经历了生态环境良好的贫营养化期(1885-1902A.D.)、轻度富营养化期(1902-1964A.D.)、中度富营养化期(1964-1988A.D.)、富营养化期(1988-1998A.D.)、中度富营养化期(1998-2003A.D.).水生生物遗存随着湖泊富营养化的发生而呈现一定的分布特征, 对富营养化敏感的奥古茨藻、荇菜、角果藻、纹沼螺、表壳虫等逐步减少.通过湖泊演化阶段与区域人类活动重大阶段的联合对比研究发现随着人类活动的增强及对湖泊生态的持续干扰, 湖泊生态演化呈现明显的阶段性, 湖泊富营养化的发生与流域强烈的人类活动如围垦与农业活动带来的营养物质输入有着直接联系, 湖泊生态环境演化对重大人类活动事件具有响应性.本研究对于认识湖泊生态环境演化与人类活动的关系、整治湖泊环境具有重要的指导意义. 相似文献
8.
G. Paladino J. P. Arrigoni P. Satti I. Morelli V. Mora F. Laos 《International Journal of Environmental Science and Technology》2016,13(9):2227-2238
Oil-based drilling cuttings comprise a large and hazardous waste stream generated by oil and gas wells drilling operations. Oil-based cuttings are muddy materials with high contents of salts and hydrocarbons. Composting strategies have shown to be effective in the biodegradation of petroleum hydrocarbons, and it offers numerous advantages in comparison with other bioremediation methods. In order to assess the effectiveness of drilling cuttings bioremediation by composting with food and garden wastes, an experiment was conducted in 60-L reactors for 151 days. Four treatments were carried out: only oil-based cuttings, two proportions (in a volume basis) of organic wastes to drilling cuttings (33 and 75 %) and only organic wastes (as a traditional composting reference), with pine-tree woodchips as bulking agent. High degradation percentages of total hydrocarbons (≈82 %), n-alkanes (≈96 %) and the 16 USEPA-listed polycyclic aromatic hydrocarbons (≈93 %) were reached in the treatment with 75 % of organic wastes, and applying 33 % of organic wastes was not more effective than not applying organic wastes for the drilling cuttings hydrocarbons biodegradation. Furthermore, in the treatment with 75 % of organic wastes, alkanes half-life and polycyclic aromatic hydrocarbons half-life were about 10 times and four times lower, respectively, than those in the treatment with 33 % of organic wastes. Possibly, lower hydrocarbons and salts initial concentrations (i.e., lower toxicity), higher microbial counts, adequate nutrient proportions and water content supported a high biological activity with a consequent elevated biodegradation rate in the treatment with 75 % of organic wastes. 相似文献
9.
A large quantity of by-product lime wastes with high water content produced from chemicals manufacturing processes has been stacked in an open area in Incheon, Korea. Highly alkaline leachate and fine dust emanating from the stacked lime wastes caused an environmental concern in the city. So evaporative drying and stabilization of the fine-grained wastes and use of the on site marine clay as a natural geomembrane liner using drying hardening were considered as a part of a landfill construction plan. Treatment of the lime wastes and marine clay was focused on maximizing the evaporative drying and the density. Evaporation experiments were conducted in field condition to understand evaporation characteristics and to evaluate actual evaporation rate of the lime wastes and marine clay. Local Class A pan evaporation data from a nearby weather station for last 30 years indicated that mean annual and monthly evaporations were 1,178.5 and 98.2 mm, respectively. Relative evaporations of the sludge lime, cake lime, and marine clay compared with the pan evaporation were 114.9, 61.9, and 119.0%, respectively. Estimates of annual evaporations from storage surfaces in the field based on the relative evaporation data were 1,353.6, 729.1, and 1,402.2 mm for the sludge lime, cake lime, and the marine clay, respectively. And annual net evaporations considering rainfall effect were estimated as between 879.9 and 1,082.9 mm for the lime sludge, between 473.9 and 583.3 mm for the lime cake, and between 981.5 and 1,191.9 mm for the marine clay. It was expected that the actual field evaporation rate would be varied with the moisture contents of the lime and the clay. Results of these experiments will provide useful implications for the drying behavior of the by-product lime and the marine clay and landfill or management plan of the storages. 相似文献
10.
11.
新疆北部石炭纪单体珊瑚新资料 总被引：1，自引：0，他引：1
文中描述的10属10个新种单体珊瑚,全部是小型角锥状、弯锥状,具中轴者居多.系发育边缘厚结带,鳞板不发育的类型.其中Rylstonia,Fasciculiamplexus,Homalophy-llites.and Tetralasma等在新疆属首次发现,不仅丰富了本区石炭纪珊瑚的属种,而且为相关地区石炭纪地层的对比提供了新的依据.同时也证明当时的北极海与我国的北方海槽及华南海是相互沟通的. 相似文献
12.
Although the post-closure thermal phase of a repository containing heat-emitting radioactive wastes is likely to be of comparatively short duration when judged against performance assessment time-scales, the effects of temperature increase and associated thermal gradients within an argillaceous host-rock are likely to be wide-ranging and include: (a) geomechanical effects on the rock-mass and engineered structures (linings, emplacement boreholes, etc.), (b) perturbation of groundwater pressures and flow by ‘aquathermal mechanisms’, (c) possible near-field effects on mass transport properties and mechanisms (e.g. coupled flow phenomena), and (d) effects on the chemical evolution of the near-field environment. Maximum allowable temperature in a repository is likely to be constrained by host-rock and/or clay buffer/backfill thermal behaviour. Given the diverse range of the thermal responses, the identification of a primary constraint on near-field temperature and the specification of a maximum allowable temperature remains problematic. 相似文献
13.
根据对巢湖490cm湖泊沉积物柱样7个AMS14C年龄的测定以及98个孢粉样品的分析,植物种类分属于86个（科）属,可以划分为6个孢粉组合带:孢粉带Ⅰ（9870～6040cal.aB.P.）代表了末次冰期之后全新世温暖气候到来之前气候转暖的早全新世过渡时期,气候呈现温和略干的特点,其中亚带Ⅰ-1（9870～7700cal.aB.P.）,Ⅰ-2（7700～6250cal.aB.P.）和Ⅰ-3（6250～6040cal.aB.P.）分别对应温暖湿润→温暖较湿→温和干燥的气候波动;孢粉带Ⅱ（6040～4860cal.aB.P.）代表中全新世温暖湿润期,水热配置条件最佳;孢粉带Ⅲ（4860～2170cal.aB.P.）体现中全新世后期温和干燥的气候,约2170cal.aB.P.干旱程度达到最高;孢粉带Ⅳ（2170～1040cal.aB.P.）反映巢湖流域由干燥向湿润气候的转型,气候总体上温和湿润;孢粉带Ⅴ（1040～200cal.aB.P.）反映了晚全新世巢湖流域温凉稍湿的气候;孢粉带Ⅵ（200cal.aB.P.至今）则体现巢湖流域处在相对温暖湿润的时期。植被类型演替大体为:以壳斗科的落叶、常绿属种为主的落叶阔叶、常绿阔叶混交林→以落叶栎类、栗属、青冈属和栲/石栎属为主的落叶阔叶、常绿阔叶混交林→以落叶栎类占绝对优势的落叶阔叶、常绿阔叶混交林→以禾本科为主的草地→以禾本科、蒿属和蓼属等为主的草丛。 相似文献
14.
The impact of disposal and treatment of coal mining wastes on environment and farmland 总被引：9，自引：0，他引：9
Zhengfu Bian Jihong Dong Shaogang Lei Hailong Leng Shouguo Mu Hui Wang 《Environmental Geology》2009,58(3):625-634
In China, coal mining wastes have traditionally been dumped in cone-shaped heaps that have the potential to pollute air, soil
and water environments and landscapes through dust generation, leachate production, self-ignition and as a consequence of
an absence of vegetation cover. Since 1980s, the disposal technique for coal mining wastes has been changing and in many instances
the wastes are now transported directly to subsided land as a fill to enable the reuse of that land. Thus, today, both coal
mining waste dumps from the past and filled subsided lands are in existence. However, the comparative impacts of these different
disposal techniques on the environment and farmland productivity have not been studied in detail. Using Dongtan (DT), Nantun
(NT) and Xinglongzhuang (XLZ) coal mines as examples, the components of coal mining wastes and their potential pollution contribution
to soil, surface water and ground water are tested in-situ. The results show that contaminants are released after self-ignition
and weathering of coal mining wastes, but they are not above the allowable environmental standards. However, despite these
findings, more and closer attention needs to be paid to the mobility, transportation and accumulation of these contaminants
in the environment over time. 相似文献
15.
The convective transfer of radionuclides by subsurface water from a geological repository of solidified high-level radioactive wastes (HLW) is considered. The repository is a cluster of wells of large diameter with HLW disposed of in the lower portions of the wells. The safe distance between wells as a function of rock properties and parameters of well loading with wastes has been estimated from mathematical modeling. A maximum permissible concentration of radionuclides in subsurface water near the ground surface above the repository is regarded as a necessary condition of safety. The estimates obtained show that well repositories allow for a higher density of solid HLW disposal than shaft storage facilities. Advantages and disadvantages of both types of storage facilities are considered in order to estimate the prospects for their use for underground disposal of solid HLW. 相似文献
16.
Kenneth S. Johnson 《Environmental Geology》1991,17(1):3-7
The Oklahoma Geological Survey has developed several maps and reports for preliminary screening of the state of Oklahoma to identify areas that are generally acceptable or unacceptable for disposal of a wide variety of waste materials. These maps and reports focus on the geologic and hydrogeologic parameters that must be evaluated in the screening process. One map (and report) shows the outcrop distribution of 35 thick shale or clay units that are generally suitable for use as host rocks for surface disposal of wastes. A second map shows the distribution of unconsolidated alluvial and terrace-deposit aquifers, and a third map shows the distribution and hydrologic character of bedrock aquifers and their recharge areas. These latter two maps show the areas in the state where special attention must be exercised in permitting storage or disposal of waste materials that could degrade the quality of groundwater. State regulatory agencies and industry are using these maps and reports in preliminary screening of the state to identify potential disposal sites. These maps in no way replace the need for site-specific investigations to prove (or disprove) the adequacy of a site to safely contain waste materials. 相似文献
17.
M. J. Fernández-Gómez M. Díaz-Raviña E. Romero R. Nogales 《International Journal of Environmental Science and Technology》2013,10(4):697-708
The enormous quantity of plant waste produced from greenhouse tomato crops is an environmental problem that should be solved by recycling that waste into valuable organic products through low-cost technologies, such as vermicomposting. Feasibility of vermicomposting greenhouse tomato-plant waste (P) using paper-mill sludge (S) as complementary waste was investigated by this study. Earthworm development in P, S, and two mixtures of both wastes was monitored over 24 weeks and compared with that in cow dung (D), an optimum organic-waste to be vermicomposted. The effectiveness of vermicomposting to biostabilize those wastes was assessed by analysing phospholipid fatty acid composition, chemical features, plant-nutrient content, metal concentration, enzyme activities, and germination index (GI). A commercial vermicompost was also analyzed and taken as a reference of vermicompost quality. Earthworms did not survive in P alone, but a mixture of P with S at a ratio of 2:1 or 1:1 resulted in earthworm development similar to that observed in D. Phospholipid fatty acid analysis revealed that earthworm activity strongly transformed initial microbiota inhabiting the wastes, giving rise to vermicompost microbial communities which were similar to that of a commercial vermicompost. Both mixtures of P and S were properly biostabilized through vermicomposting, as indicated by decreases in their C:N ratio and enzyme activities together with increases in their degree of maturity (GI ~ 100 %) after the process. This study demonstrates that the vermicomposting of tomato-plant waste together with paper-mill sludge allows the recycling of both wastes, thereby improving the environmental sustainability of greenhouse crops. 相似文献
18.
Mining wastes and calcines from two abandoned mining areas (Valle del Azogue and Bayarque in Almería) have been characterized. In the mining wastes, the dominant mercury phases are cinnabar and elemental mercury in the matrix. In the calcines, however, the dominant mercury phase is elemental mercury bounded to the matrix. Water-leaching experiments were conducted on low-grade stockpiles and calcines in order to simulate the mobilization of mercury by runoff under environmental conditions. The laboratory column-leaching experiments show a possible mobilization of mercury from Hg0 dissolution, colloid transport and a possible dissolution of calomel and other soluble phases in the mine wastes from the Valle del Azogue and Bayarque mines. Equilibrium speciation modeling of Hg, conducted using the numerical code MINTEQ, showed that the theoretical dominant mercury species in the calcine and mining wastes samples are Hg(OH)2, HgCl2, HgClOH and Hg0. In some leachates obtained from the Valle del Azogue mining wastes (sample A06), the high Hg concentrations may indicate the possible dissolution of mineral phases such as calomel and other soluble phases, which are subsaturated. The environmental results indicate a great environmental mobility of mercury, especially during wet episodes associated with intense precipitation events, when there are significative amounts of secondary soluble minerals. 相似文献
19.
S. Jacob A. D. Chintagunta R. Banerjee 《International Journal of Environmental Science and Technology》2016,13(10):2363-2374
Potato being the staple vegetable in India is widely cultivated and processed for different value additions. During processing of potato, a huge amount of waste is generated in the form of peel and meat (mash). These wastes constitute a potential feedstock for biogas generation. The present study is focused on mitigation of acidogenesis that occurs during early stages of anaerobic digestion (AD) of potato waste which eventually inhibits the process of methanogenesis. A novel strategy of selective digestion was adopted in which the leachate and solid slurry resulting from the first stage digestion were further subjected to second stage by separating the solid and liquid phases. The obtained results indicated that stepwise digestion enhanced biomethane yield with an increase in methane percent from 46.47 to 60.4 % and reduction in total COD to about 94 %. Another novel strategy adopted in this study was the use of specifically developed microbial consortia for AD of potato wastes instead of conventional inoculum for production of biogas. The obtained yield is at par with the conventional inoculums which suggests that the developed consortia could act as potential substitute. The present study paves the way for sustainable utilization of industrial potato wastes for bioenergy production by overcoming the problems associated with conventional processes. 相似文献
20.
In this paper it will be shown how the problem of solid wastes collection and disposal can be formulated as a dynamic mixed-integer linear programming model. The developed model can be used for the determination of sites for landfills, transfer stations, recycling centers and the periodical routing of collection vehicles in order to reduce the cost of municipal solid wastes transport and disposal. The model has been tested by applying it to a hypothetical municipal solid waste system. The possibility of using the developed model for managing and planning the municipal solid wastes system of the Dammam metropolitan area, Saudi Arabia will be discussed.The model is general in structure and can be used to address other problems such as the problem of hazardous wastes management, petroleum products distribution and food processing industries. 相似文献