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231.
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选用钢铁行业袋式除尘用滤料,采用泡点法进行孔径及孔径分布测试,并进行了除尘滤料冷静态过滤性能测试。通过对实验数据分析得到:针刺滤料平均孔径为22.22~26.83μm,孔径分散程度较高;覆膜针刺过滤材料平均孔径仅为1.0μm左右,孔径分布较为集中;针刺滤料的孔径会影响到其透气性,透气性随着最大孔径的增加而增加;针刺滤料孔径及孔径分布对过滤效率有直接的影响,孔径越大,孔径分布分散程度越高,过滤效率越低,过滤阻力越小;过滤风速为1.0 m/min时覆膜滤料对微细颗粒物的捕集效率达到80%左右,约为普通针刺毡滤料的2~4倍,阻力约为普通针刺毡滤料的14~32倍。 相似文献
233.
垃圾渗滤液浓度高、成分复杂,难以处理,常规生化处理方法存在缺点,碟管式反渗透(DTRO)是针对垃圾渗滤液的水质特点而设计的,出水水质好,受进水水质影响很小,在国外的垃圾渗滤液处理中应用广泛。在分析DTRO工艺特点的基础上,探讨了两级DTRO工艺流程、特点、机理和浓缩液的处理方法,并论述了DTRO运行参数对膜片性能的影响。掌握系统运行和膜清洗时各项参数对膜性能的影响趋势,优化预处理工艺对降低处理成本,指导同类工艺的优化操作具有一定的参考价值。 相似文献
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聚合物驱采出水处理工艺研究 总被引:7,自引:0,他引:7
聚合物驱油技术在大庆油田得到广泛应用,由于采出水粘度大、油珠粒径小,其处理难度大于油田常规水驱采出水。通过对聚合物驱采出水的特性分析,并在现场分别进行了以横向流除油器(串联DTH聚结器)和水力旋流器为主体的工艺试验。其工艺参数分别为:横向流除油器和DTH聚结除油器的处理量均为85 m3/h,有效停留时间为2.4 h。过滤器为石英砂、磁铁矿双层滤料,处理量为20 m3/h,过滤周期24 h,反冲洗时间为15 min,一次和二次过滤的滤速分别为12 m3/h和8 m3/h。试验结果表明:两种工艺均可代替现有的沉降过滤工艺处理聚合物驱采出水。 相似文献
238.
Z. Milán E. Sánchez R. Borja K. Ilangovan A. Pellón N. Rovirosa 《Journal of environmental science and health. Part. B》2013,48(2):305-332
Abstract This study was carried out in a pilot plant for the treatment of anaerobic cattle manure waste. The pilot plant consisted of a semicontinous anaerobic reactor, a settling tank, a filtration process and an ionic exchange column. The study was focused on the filtration process, with natural zeolite as filtering material. In the filtration process different media sizes of natural zeolites packed in columns were tested. The ranges of media size were 0.4 ‐ 1.0, 1.0 ‐ 3.0 and 3.0 ‐ 5.0 mm. Filtration systems operated by gravity flow from 2 to 10 m3m‐2h‐1. The process control was done by assays of solids, turbidity, total and soluble COD, ammonium and orthophosphate. The results showed a better behaviour in the filters packed with a media size range between 1.0 and 3.0 mm, operating at 7 m3m‐2h‐1, principally when effluent gross particles were previously retained in an Heterogeneous Media Filter, operating at 4 m3m‐2h‐1. The head losses diagrams in the filter runs were obtained, at each operational conditions. The hydraulic behaviour of traditional silica sand and natural zeolite beds were compared at the same operational conditions. 相似文献
239.
Katarzyna Majchrzycka Beata Gutarowska Agnieszka Brochocka 《International journal of occupational safety and ergonomics》2013,19(2):275-280
The second part of the article presents the results of a study of antimicrobial activity of filter nonwovens with an addition of biocides, as a function of the presence of sweat in the environment and the method of microbe deposition on a nonwoven in the form of a liquid and a bioaerosol. At the same time, the filtration efficiency of nonwovens against microorganisms in the form of a bioaerosol was tested with the dynamic method. The results showed that the addition of sweat on the surface of a nonwoven resulted in an insignificant decrease of biological activity that still remained high. Moreover, an active nonwoven showed biostatic and biocidal activity only when microbes were deposited on the surface in the form of a solution. The nonwoven did not show any biological activity after deposition of microorganisms with the dynamical method in the form of a bioaerosol. 相似文献
240.
The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge of the aerosol.To a lesser degree the filtration process depended on the sign of the charge and the relative humidity of the air. A significant correlation was found between the increase in the penetration and the decrease in breathing resistance while the filter was being loaded.The effect of resuspension (tearing off and re-deposition of dust agglomerates inside the filter) on the filtration process very significant. It was also observed that under certain conditions electrostatic filter materials lost their protection properties. 相似文献