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541.
542.
炼油污水处理装置的三泥脱水实验表明,剩余污泥的脱水性能最好。根据实验结果,将浮渣与剩余污泥按比例混合进行脱水,连续少量掺入油泥,调整转速与混凝剂用量后取得较好的脱水效果。在离心机处理量13~15m3/h,离转速3000r/min,差转速5~7r/min,混凝剂量5kg/h的工况下,离心机所产泥饼含水率<85%、滤液ρ(COD)<800mg/L。脱水处理直接成本19.6元/m3。 相似文献
543.
544.
随着内蒙古自治区经济的飞速发展,带来了一系列的环境风险问题。自治区也应该建立与之相配套的应急监测预警体系,本文着重介绍了该体系建设的相关内容。 相似文献
545.
硅铁电炉目前应用比较广泛,分析硅铁的生产工艺和烟气处理不仅是完成节能减排的需要,也是保护环境的重要手段。 相似文献
546.
对我国开展大气VOCs监测的必要性、监测现状以及主要使用的监测方法进行了分析。目前,我国已初步建立了大气VOCs手工与自动监测网络,主要采用预浓缩-热脱附-气相色谱-质谱/氢火焰离子化检测器法进行PAMS组分和TO-15组分分析,利用高效液相色谱法进行13种醛、酮类组分分析。目前大气VOCs监测还存在数据质量、灵敏度有待提高,不同设备或方法监测结果一致性较差等问题。为此在VOCs监测过程中应进一步加强质量保证与质量控制,并尝试通过提高预浓缩装置除水和干扰物效率、提升进样量等多种手段提高监测灵敏度。 相似文献
547.
官金华 《中国环境管理干部学院学报》2013,(3):88-91
地方政府投融资平台在促进地方经济发展,推动城市化进程,应对国际金融危机等方面发挥了重要作用。但由于缺乏统一的管理,各地方政府投融资平台财务状况披露不公开、不透明,债务风险急剧扩大,引起了有关部门和专家学者的高度关注。各地方政府应将融资平台的各种信息,特别是债务情况,定期向主管部门报告,建立地方投融资平台信用评价方法,使得投融资平台朝着健康、良性的方向发展。 相似文献
548.
Wenling Guan Juncheng Jiang Dongliang Sun 《Journal of Loss Prevention in the Process Industries》2011,24(5):699-704
Explosions of vessels containing high pressure gases or superheated liquids are a common accident in the chemical industry. Fragments are the most information-rich physical evidence in accident analysis. A method is presented to calculate the total explosion energy based on the characteristics of fragments from the scene of an accident, such as mass, horizontal displacement, etc. The implicit expressions of the initial velocity can be obtained through analysing the trajectory equations of the fragments and the data obtained from the scene of the accident. The total energy is calculated from the relationship between the total explosion energy and the kinetic energy of the fragment. During the calculation there are some uncertain parameters, e.g., the energy factor and the initial angle. To solve the parameter uncertainties, a Monte-Carlo simulation is introduced. Analysis of an industrial accident shows that it is feasible to estimate the total explosion energy using the maximum probability density interval with the proposed methodology. 相似文献
549.
Pierre Hennebert Astrid Avellan Junfang Yan Olivier Aguerre-Chariol 《Waste management (New York, N.Y.)》2013,33(9):1870-1881
The potential colloids release from a large panel of 25 solid industrial and municipal waste leachates, contaminated soil, contaminated sediments and landfill leachates was studied. Standardized leaching, cascade filtrations and measurement of element concentrations in the microfiltrate (MF) and ultrafiltrate (UF) fraction were used to easily detect colloids potentially released by waste. Precautions against CO2 capture by alkaline leachates, or bacterial re-growth in leachates from wastes containing organic matter should be taken. Most of the colloidal particles were visible by transmission electron microscopy with energy dispersion spectrometry (TEM–EDS) if their elemental MF concentration is greater than 200 μg l?1. If the samples are dried during the preparation for microscopy, neoformation of particles can occur from the soluble part of the element. Size distribution analysis measured by photon correlation spectroscopy (PCS) were frequently unvalid, particularly due to polydispersity and/or too low concentrations in the leachates. A low sensitivity device is required, and further improvement is desirable in that field. For some waste leachates, particles had a zeta potential strong enough to remain in suspension. Mn, As, Co, Pb, Sn, Zn had always a colloidal form (MF concentration/UF concentration > 1.5) and total organic carbon (TOC), Fe, P, Ba, Cr, Cu, Ni are partly colloidal for more than half of the samples). Nearly all the micro-pollutants (As, Ba, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, V and Zn) were found at least once in colloidal form greater than 100 μg l?1. In particular, the colloidal forms of Zn were always by far more concentrated than its dissolved form. The TEM–EDS method showed various particles, including manufactured nanoparticles (organic polymer, TiO2, particles with Sr, La, Ce, Nd). All the waste had at least one element detected as colloidal. The solid waste leachates contained significant amount of colloids different in elemental composition from natural ones. The majority of the elements were in colloidal form for wastes of packaging (3), a steel slag, a sludge from hydrometallurgy, composts (2), a dredged sediment (#18), an As contaminated soil and two active landfill leachates.These results showed that cascade filtration and ICP elemental analysis seems valid methods in this field, and that electronic microscopy with elemental detection allows to identify particles. Particles can be formed from dissolved elements during TEM sample preparation and cross-checking with MF and UF composition by ICP is useful. The colloidal fraction of leachate of waste seems to be a significant source term, and should be taken into account in studies of emission and transfer of contaminants in the environment. Standardized cross-filtration method could be amended for the presence of colloids in waste leachates. 相似文献
550.
目前我国农用地资源定级很少运用修正法,少数学者对修正法定级做过尝试性的实证研究工作,以期探讨修正法定级技术路线的科学性与可行性。在前人研究的基础上,以佛山高明区为例,探讨了修正法定级之修正基础的确定、修正因素的选择、修正系数的计算、定级指数的确定等几个关键技术步骤,提出了以农用地自然质量等指数作为修正基础,采用标准化方法对修正因素分值进行订正,用连乘法计算农用地质量定级指数来划分农用地级别的修正法定级的技术路线,并与因素法定级的成果进行对比分析与验证。 相似文献