【作者】 贺湘兵；

【导师】 韩建；

【作者基本信息】 浙江理工大学 ， 纺织工程， 2011， 硕士

【摘要】 造成大气污染的主要原因是火力发电、钢铁、水泥、冶金、化工、垃圾焚烧等行业的烟气排放。这些烟气的主要成分有烟尘、SO₂、NO_x、HCl、CO、O₂、氟化物和水分等,一般情况下烟气的温度范围为140²40℃。随着人们环保意识及对环境改善的要求日益强烈,提高烟气排放的洁净程度成为必要措施。因此,耐高温滤料的研究成为当代的一个重要课题。本课题的主要研究内容包括:1、研究PPS纤维的耐高温、耐碱、耐酸及耐混合酸等性能;2、探讨玄武岩基布的力学性能及其耐酸碱性能;3、研究针刺工艺对玄武岩基/PPS滤料力学性能的影响;4、研究单面烧毛轧光、单面涂胶、单面覆膜等后整理工艺对滤料性能的影响。通过以上研究,得到的主要结论如下:1、通过单纤强力仪、场发射扫描电镜、差示扫描量热仪测试了处理前后PPS纤维的力学性能、表面形貌和内部结构的变化。实验结果表明:当温度高于230℃时,PPS纤维的耐高温性能较差,随着处理温度的升高,纤维表面凸起的颗粒变大且增多,其断裂强力保持率下降,熔点和熔融热都增大,结晶变得完善;PPS纤维有较好耐碱性能;PPS耐H₂SO₄性能好,耐HCl性能一般,耐HNO3性能较差,经HCl、HNO₃处理后,纤维表面出现凹槽和裂缝,其断裂强力保持率、熔点、熔融热随处理时间和温度的增加而减小;PPS纤维的耐HNO3+HCl混合酸比纯HNO₃腐蚀性能差。2、通过体视显微镜和织物强力仪观察测试了玄武岩基布的表面形貌和力学性能。结果表明:玄武岩斜纹基布的断裂强力大于平纹基布的断裂强力;玄武岩基布不耐碱,耐HNO₃性能较好,耐H2SO4性能一般,耐HCl性能差,经HCl处理后基布由金黄色变成银色且断裂强力大幅下降。3、以玄武岩机织物为基布,以PPS纤维为网层,通过改变针刺道数制备了不同针刺密度的PPS针刺滤料,并分析了针刺密度对不同玄武岩基布和玄武岩基/PPS滤料的力学性能的影响。结果表明:玄武岩基布和玄武岩基/PPS滤料的断裂强力和断裂伸长率都随针刺密度的增加而减小;纤维束规格相同时,经相同针刺密度针刺后,斜纹基布较平纹基布平整,斜纹基布和斜纹基PPS滤料的断裂强力大于平纹基布和平纹基PPS滤料的断裂强力。4、通过电子天平、数字式织物厚度仪、场发射扫描电子显微镜、织物电子强力仪、数字式织物透气仪、孔径测定仪、过滤测试平台测试后整理处理前后滤料的单位面积重量、厚度、力学、透气、孔径、过滤效率、过滤阻力等性能。结果表明:烧毛轧光处理使滤料变得平整密实,厚度减小,透气量减小到将近处理前的一半,平均孔径减小,过滤效率提高;单面涂胶处理使滤料的断裂强力增大,透气量减小到涂胶前的一半,孔径减小,过滤阻力增大,过滤效率提高;单面覆膜使滤料孔径减小,过滤阻力急剧升高,对小粒径粒子过滤效率大幅提高,对粒子粒径小于0.3μm的微粒的过滤效率均大于94%,当粒子粒径大于3μm时,过滤效率达到100%。更多还原

【Abstract】 Air pollutions were mainly caused by exhaust gases, which included dusts, hydrochloride, O₂, CO, SO₂, NO_x, H₂O and emitted from coal-fired power plant, cement plants, steel works, incinerating plants at the temperature of 160²40℃. People paid more attention to environmental protection and improvement of the clean level of emitted gases. Thus, the study of high temperature filtration became an important work.The aim of the study was to investigate the mechanical properties of PPS fibers in high temperature, acids and alkali, the mechanical and chemical resistant properties of basalt fabric, the effect of needle-punched on the properties of basalt fabric/PPS filter and the effect of finishing on the properties of basalt fabric/PPS filtration.The results showed that HCl and HNO3 had obviously detrimental effect on the properties of PPS fibers relative to NaOH and H₂SO₄. Many cracks and holes appeared on the surface of PPS fibers after HCl or HNO₃ exposure. The breaking strength and breaking elongation of PPS fibers were decreased as the increasing of concentrations and extension of time. Their melting heat was mostly affected by HNO3 among those acids and alkali. HCl accelerated the degradation of HNO3 on PPS fibers. When the treatment temperature was over 230℃, there were more and more small particles appeared on the surface of the PPS fibers as the increase of the treatment temperature.Tensile strength of basalt twill fabric was greater than that of plain fabric. Basalt fabric is not alkali resistance, good performance in HNO3 resistance, general performance in H2SO4 resistance, poor performance in HCl resistance. The color of basalt fabrics changed from the golden yellow to Silver and the breaking strength dropped significantly after HCl treatment.The breaking strength and breaking elongation rate of basalt fabric and the basalt based/ PPS filter decreased as increasing of the needling density. The breaking strength of basalt twill fabric and basalt twill fabric based / PPS filter than that of the plain fabric and plain fabric based PPS filter punched by the same needling density.Filter became smoother and denser after the singeing and calendering treatment, which also decreased the thickness, reduced gas transmission to be nearly half of the untreated filter, decreased the average pore size and enhanced the filtration efficient. Single-side gelatinizing treatment increased the breaking strength of the filter, reduced gas transmission to be half of the pre-coating filter and increased the filtration efficient. Single-side tectorial membrane treatment decreased the media pore size and enhanced filtration efficient of the filter. The filtration efficient against the particle size bigger than 0.3μm was over 94%, and the filtration efficient increased to 100% when the particle size was greater than 3μm.更多还原